Haplogroups Research Articles

Comparison of outcomes after human leukocyte antigen-matched and haploidentical hematopoietic stem-cell transplantation for multiple myeloma.

Background:Allogeneic stem-cell transplantation (SCT) is a well-established immunotherapeutic strategy for multiple myeloma (MM) with a potent and often sustained graft-vs.-myeloma effect. This multicenter investigation aimed to analyze the complications and survival of haploidentical SCT in patients with MM, and compare the main outcomes with matched-related donors (MRDs).Methods:Haploidentical and MRD SCT was identified from a cohort of 97 patients with MM who received a myeloablative transplantation in 13 hospitals from May 2001 to December 2017. A matched-pair analysis was designed. For each haplo recipient, the recipients were randomly selected from the MRD group and were matched according to the following criteria: year of the hematopoietic SCT (±2 years), disease status at transplantation, and the length of follow-up.Results:Seventy cases received MRD and 27 received haploidentical transplantation. The two groups showed no significant differences regarding age, gender, cytogenetic risk, and diagnostic stage. The cumulative incidences of non-relapse mortality (NRM) at 1 and 3 years based on donor type were 20.5% (95% confidence interval [CI], 10.90–30.10%) and 24.2% (95% CI, 13.81–34.59%) for the MRD group and 16.80% (95% CI, 1.71–31.89%) and 28.70% (95% CI, 8.71–48.69%) for the haplo group, respectively. Cumulative incidence of NRM did not differ significantly between the two groups (χ2 = 0.031, P = 0.861). The cumulative incidences of progression-free survival (PFS) and 1 year and 3 years by type of donors were 59.8% (95% CI, 48.24–71.36%) and 45.4% (95% CI, 33.44–57.36%), and 65.6% (95% CI, 47.18–84.02%) and 26.8% (95% CI, 7.59–46. 01%) for MRD and haploidentical donor, respectively. Cumulative incidence of PFS did not differ significantly between the two groups (χ2 = 0.182, P = 0.670). In multivariate analyses, no statistically significant differences were observed between haploidentical and MRD for relapse, NRM, PFS, and overall survival. There were no statistically differences on main outcomes after haploidentical and MRD.Conclusion:Haploidentical SCT could be performed safely and feasibly for patients with MM in need.

PF775 MONOSOMY 7 ALONE OR WITH OTHER CHROMOSOMAL ABNORMALITIES SIGNIFICANTLY AFFECT SURVIVAL OF SECONDARY AML PATIENTS TREATED WITH ALLOGENEIC- SCT

Background: T-cell replete Haploidentical stem cell transplantation (Haplo-SCT) with high dose post-transplant cyclophosphamide (PT-Cy) is being increasingly used for patients when a HLA identical sibling or a matched related donor is not available. With regard to inborn errors of metabolism (IEM) or primary immunodeficiency which need a hematopoietic stem cell transplantation (HSCT) for cure, haplo-SCT could be an alternative option. However, there is insufficient data on the efficiency and safety of the procedure of haplo-SCT with PT-Cy in patients with nonmalignant genetic diseases. Aims: The aim of the present study is to evaluate the feasibility and safety of haplo-SCT with PT-Cy in patients with nonmalignant genetic diseases compared with HLA matched donor transplantation. Methods: We retrospectively analyzed 16 patients (Haplo group) receiving Haplo-SCT with PT-Cy from peripheral blood graft source, and 20 patients (Matched group) receiving HSCT from related matched (n = 4), unrelated 9–10/10 matched donors (n = 16) between Jan 2014 and Feb 2018 at Seoul National University Children's Hospital. Three chronic granulomatous disease (CGD), 5 adrenoleukodystrophy (ALD), 4 Krabbe disease, and 4 others were included in Haplo group, whereas 11 CGD, 1 ALD, 1 Krabbe disease, 3 congenital neutropenia, and 4 other diseases in Matched group. We used an intensive daily pharmacokinetic monitoring method for busulfan dosing for effective myeloablation and to reduce toxicity. The total target area under the curve (AUC) of busulfan was set at 74,000 to 76,000 μg × h/L. Targeted busulfan, fludarabine were used in both groups for the conditioning regimen, while cyclophosphamide was included in Haplo group, and anti-thymocyte globulin in Matched group. Results: The outcomes of haplo group and Matched group, respectively, are discussed. The median follow-up time were 27.6 months (range, 11.9–60.8), and 34.2 months (range, 12.5–59.9), respectively. The cumulative incidence (CI) rates of neutrophil engraftment in haplo and control groups were 93.8% and 95.0%. The median days of neutrophil engraftment were 14 days and 11 days, and those of platelet engraftment were 34 days and 17 days, respectively. The both groups did not differ in terms of transplantation-associated complications (hepatic veno-occlusive disease, CMV reactivation, hepatic toxicity, hemorrhagic cystitis). For 13 patients with IEM, the post-HSCT brain MRI findings were reported as similar to the pre-HSCT one. In particular, 2 ALD patients in Haplo group who did not showed neurologic symptom before HSCT (pre-HSCT Loes scores were 0 and 2, respectively) are still normal with regard to neurologic status at median follow-up time 41 months and 18 months, respectively. The CI rates of grade II–IV, grade III-IV acute and extensive chronic graft versus host disease were 45.0% versus 40.0% (P = 0.68), 6.0% versus 20.0% (P = 0.263) and 13.3% versus 26.7% (P = 0.335), respectively. The event-free survival rates at 2 years (93.8% versus 95.0%, P = 0.856) were similar and the overall survival rates were 100% in both groups. Summary/Conclusion: The present study shows that haplo-SCT using PT-Cy, along with a targeted busulfan-based myeloablative conditioning regimen, is a safe and promising therapeutic option for patients with nonmalignant genetic diseases. In particular, it could be useful for patients in urgent need of HSCT who lack a sibling donor or do not have enough time to find a suitable unrelated donor.

PF774 EXCELLENT OUTCOME OF MATCHED DONOR AND HAPLOIDENTICAL PERIPHERAL BLOOD STEM CELL TRANSPLANTATION WITH TARGETED BUSULFAN‐BASED MYELOABLATIVE CONDITIONING IN PATIENTS WITH NONMALIGNANT GENETIC DISEASES

Background:T‐cell replete Haploidentical stem cell transplantation (Haplo‐SCT) with high dose post‐transplant cyclophosphamide (PT‐Cy) is being increasingly used for patients when a HLA identical sibling or a matched related donor is not available. With regard to inborn errors of metabolism (IEM) or primary immunodeficiency which need a hematopoietic stem cell transplantation (HSCT) for cure, haplo‐SCT could be an alternative option. However, there is insufficient data on the efficiency and safety of the procedure of haplo‐SCT with PT‐Cy in patients with nonmalignant genetic diseases.Aims:The aim of the present study is to evaluate the feasibility and safety of haplo‐SCT with PT‐Cy in patients with nonmalignant genetic diseases compared with HLA matched donor transplantation.Methods:We retrospectively analyzed 16 patients (Haplo group) receiving Haplo‐SCT with PT‐Cy from peripheral blood graft source, and 20 patients (Matched group) receiving HSCT from related matched (n = 4), unrelated 9–10/10 matched donors (n = 16) between Jan 2014 and Feb 2018 at Seoul National University Children's Hospital. Three chronic granulomatous disease (CGD), 5 adrenoleukodystrophy (ALD), 4 Krabbe disease, and 4 others were included in Haplo group, whereas 11 CGD, 1 ALD, 1 Krabbe disease, 3 congenital neutropenia, and 4 other diseases in Matched group. We used an intensive daily pharmacokinetic monitoring method for busulfan dosing for effective myeloablation and to reduce toxicity. The total target area under the curve (AUC) of busulfan was set at 74,000 to 76,000 μg × h/L. Targeted busulfan, fludarabine were used in both groups for the conditioning regimen, while cyclophosphamide was included in Haplo group, and anti‐thymocyte globulin in Matched group.Results:The outcomes of haplo group and Matched group, respectively, are discussed. The median follow‐up time were 27.6 months (range, 11.9–60.8), and 34.2 months (range, 12.5–59.9), respectively. The cumulative incidence (CI) rates of neutrophil engraftment in haplo and control groups were 93.8% and 95.0%. The median days of neutrophil engraftment were 14 days and 11 days, and those of platelet engraftment were 34 days and 17 days, respectively. The both groups did not differ in terms of transplantation‐associated complications (hepatic veno‐occlusive disease, CMV reactivation, hepatic toxicity, hemorrhagic cystitis). For 13 patients with IEM, the post‐HSCT brain MRI findings were reported as similar to the pre‐HSCT one. In particular, 2 ALD patients in Haplo group who did not showed neurologic symptom before HSCT (pre‐HSCT Loes scores were 0 and 2, respectively) are still normal with regard to neurologic status at median follow‐up time 41 months and 18 months, respectively. The CI rates of grade II–IV, grade III‐IV acute and extensive chronic graft versus host disease were 45.0% versus 40.0% (P = 0.68), 6.0% versus 20.0% (P = 0.263) and 13.3% versus 26.7% (P = 0.335), respectively. The event‐free survival rates at 2 years (93.8% versus 95.0%, P = 0.856) were similar and the overall survival rates were 100% in both groups.Summary/Conclusion:The present study shows that haplo‐SCT using PT‐Cy, along with a targeted busulfan‐based myeloablative conditioning regimen, is a safe and promising therapeutic option for patients with nonmalignant genetic diseases. In particular, it could be useful for patients in urgent need of HSCT who lack a sibling donor or do not have enough time to find a suitable unrelated donor.

Post-transplant cyclophosphamide in matched and haploidentical transplant recipients receiving myeloablative timed sequential busulfan conditioning regimen: Results of a phase II study.

7007 Background: Myeloablative stem cell transplants have a lower rate of relapse than reduced intensity regimens. Timed sequential busulfan (TSB) with fludarabine (Flu) is a promising myeloablative regimen for patients undergoing matched sibling (MSD) or unrelated (MUD) donor transplantation (HCT) with low non-relapse mortality (NRM) (Popat et al Lancet Haematology 2018), but was not tested in haploidentical (haplo). Also, whether this approach can be used with post-transplant cyclophosphamide (PTCy) in MSD, MUD and haplo HCT is unknown. To address these issues, we conducted a prospective phase II study. Methods: Patients with hematological malignancies with MSD, MUD or haplo donor were eligible. They received fixed doses of Busulfan(BU) 80mg/m2 either on day -13 and -12 (n=45) or on -20 and -13 (n=10). Then, Flu 40mg/m2 was given on day -6 to -2 followed by Bu dosed to achieve target area under the curve (AUC) of 20,000 umol/min for the whole course based on pharmacokinetic studies. Thiotepa 5mg/kg was given on day -7 to haplo group. GVHD prophylaxis was PTCy 50mg/kg on day 3 and 4 and tacrolimus. Haplo and later MUD recipients also received mycophenolate mofetil. Results: 55 patients with a median age of 47 (15-65) years were enrolled. 30 patients had AML or MDS, 9 CML or MPD, 5 lymphoma, 5 myeloma and 6 ALL. About half had haplo 26 (47%); others had MUD 18 (33%) or MSD 11(20%). Disease risk index was high in 18 (32%), intermediate in 32 (58%), and low in 5 (9%) patients. Comorbidity score was ≥3 in 22 (40%) patients. With a median follow up of 17 months (5-28), 1-year OS, PFS, NRM and relapse rates were 71% (60-84%), 63% (51-77%), 20% (9-31%), and 17% (7-27%), respectively [Table]. There were no graft failures. Day 100 grade II-IV and III-IV acute GVHD rates were 38% (25-51%) and 9% (95% CI 1-17%), respectively; 1-year chronic GVHD and extensive chronic GVHD rates were 10% (2-28%) and 8% (0-15%), respectively. 1-year OS in MSD, MUD and haplo groups were 91% (75-100%), 72% (54-96%), and 62% (45-83%) respectively (P=0.11). Conclusions: Myeloablative TSB with PTCy is feasible in MSD, MUD and haplo HCT. It lowers the incidence of severe acute and chronic GVHD without apparent increase in relapse. Clinical trial information: NCT02861417. [Table: see text]

HLA-Matched Sibling Versus Haploidentical Hematopoietic Cell Transplantation (HCT) in Patients with Acute Myeloid Leukemia (AML) in First Complete Remission (CR1)

Haploidentical (Haplo) HCT using post-transplantation cyclophosphamide (PT-Cy) has improved donor availability. However, a matched sibling donor (MSD) is still considered the optimal donor. Using the CIBMTR database, we compared outcomes after MSD HCT vs. PT-Cy-based Haplo-HCT in AML patients in CR1. Data from 1,205 adult CR1 AML patients (PT-Cy-based Haplo-HCT: 336, MSD with calcineurin inhibitor-based GVHD prophylaxis: 869) (2008-2015) were analyzed. The Haplo group included more reduced-intensity conditioning (65% vs. 30%) and bone marrow grafts (62% vs. 7%), consistent with current practice (Table 1). In univariate analysis, the Haplo group had less chronic GVHD (26 [21-31]% vs. 56 [53-60]% at 3 years, p Our results suggest similar outcomes after current standard practices of PT-Cy-based Haplo-HCT using mostly bone marrow vs. MSD HCT using mostly peripheral blood, except for less cGVHD after Haplo-HCT. Although the groups were balanced for many important variables, the tight relationship of donor type with graft source and conditioning intensity may have influenced our findings.

Haploidentical (HAPLO) Vs Umbilical Cord Blood (UCB) Allogeneic Hematopoieitc Cell Transplant (ALLO-HCT) in Patients ≥ 60 Years with Hematological Malignancies

Introduction Allo HCT is a curative option for many aggressive hematological malignancies that increase with age. HAPLO donors and UCB are alternative sources of hematopietic cells for patients lacking a matched sibling or unrelated donor. The choice between UCB and HAPLO HCT is challenging as there is no direct comparison between the two. Objectives The goal of this study is to compare outcomes of UCB vs HAPLO HCT in patients ≥ 60 years who received an allo-HCT at UMass Memorial Medical Center over the past 5 years. Methods We retrospectively analyzed data of all patients ≥60 years who underwent allo-HCT with either HAPLO or UCB between June 2013 – June 2018. Patient characteristics were collected from the electronic medical records. We assessed rates of neutrophil and platelet engraftment, length of hospitalization, rates of acute (a) and chronic (c) graft vs host disease (GVHD), relapse rates, as well as day 100 and 1 year nonrelapse mortality (NRM) and overall survival (OS) rates. Results Tables 1 & 2 summarize patient characteristics and HCT outcomes. 22 patients were identified from the database. All patients received RIC with Thiotepa/Fludarabine/Melphalan with the exception of 1 UCB patient who received Fludarabine/Cyclophosphamide. UCB patients received GVHD prophylaxis with tacrolimus/mycophenolate/antithymocyte globulin (ATG). HAPLO cohort received GVHD prophylaxis with post-transplant cyclophosphamide (PTCy) plus tacrolimus/sirolimus/ATG. Conclusion Despite the higher HCT-CI/age in the HAPLO group, its day-100 NRM rate was lower. Although day 100 OS was superior in HAPLO, the 1-year OS rate was similar in both cohorts. The use of PTCy in HAPLO GVHD prophylaxis may explain the higher relapse rate. Length of hospitalization is markedly shorter for HAPLO, which may translate into lower HCT cost. These results need to be validated in a prospective randomized trial. UCB and HAPLO HCT are both feasible in patients ≥ 60 years. The choice should rely on the urgency of HCT, available cell dose and the expertise of the HCT center.

Comparison of Haploidentical Transplantation with Post-Transplantation Cyclophosphamide and Umbilical Cord Blood Transplantation in Children and Adolescents with Hematologic Malignancies after Targeted Busulfan-Based Myeloablative Conditioning Using Intensive Pharmacokinetic Monitoring

Introduction: Haploidentical related donor (Haplo) and umbilical cord blood (UCB) stem cell sources represent common alternative donor strategies used when a matched sibling donor or matched unrelated donor is not available for hematopoietic stem cell transplantation (HSCT). The aim of this study was to compare the results of graft source on outcome of children and adolescents with hematologic malignancies after Haplo and UCB transplantation in the setting of targeted busulfan-based myeloablative conditioning using intensive pharmacokinetic (PK) monitoring.Patients and methods: We retrospectively analyzed outcomes in 140 pediatric patients with hematologic malignancies who received allogeneic HSCT from Haplo donors (n=36), UCB (n=24), and unrelated donors (n=80) in Seoul National University Children's Hospital from January 2009 to February 2018. Because UCB transplantation had been conducted until 2016 while Haplo transplantation using posttransplantation cyclophosphamide (PTCy) was started from 2014 in our institution, differences over time of HSCT must be considered to compare them. Therefore, unrelated HSCT group was divided into Unrelated A group (n=51) who received HSCT from 2009 to 2013 and Unrelated B group (n=29) from 2014, which were compared first with the purpose of using them as a control to compare Haplo and UCB groups. Patients who received the first allogenic HSCT using an intensive PK monitoring, targeted busulfan-based myeloablative conditioning were included. The majority of UCB and unrelated groups received busulfan, fludarabine ± etoposide regimen with antithymocyte globulin. For graft-versus-host disease (GVHD) prophylaxis, cyclosporine and mycophenolate mofetil were used in UCB group while tacrolimus and methotrexate in unrelated groups. Busulfan, fludarabine and cyclophosphamide with PTCy, tacrolimus and methotrexate for GVHD prophylaxis were used in Haplo group.Results: First of all, Unrelated A group was compared to Unrelated B group. The median follow-up time were 5.7 years (0.2-9.5) and 1.8 years (0.3-4.5) in the Unrelated A and Unrelated B groups, respectively. The event-free survival (EFS) rates at 2 years (78.1±5.8% versus 72.3±9.1%, P=0.917) and overall survival (OS) rates at 2 years (83.7±5.3% versus 77.8±9.1%, P=0.874) in Unrelated A and B groups were similar. Under the assumption that there was no significant survival difference over time of HSCT from 2009 to 2013 and that from 2014 in our institution, the outcomes of Haplo and UCB groups were compared subsequently. The median follow-up time were 4.8 years (0.1-9.3) and 1.8 years (0.3-4.5), respectively. The median time to neutrophil and platelet recovery were 15 days (13-21) versus 14 days (12-40) (P=0.059), and 27 days (13-71) versus 46 days (21-77) (P<0.001) in Haplo and UCB groups, respectively. Engraftment failure occurred in 1 patient of UCB group. The cumulative incidence (CI) rates of acute GVHD grade II-IV, grade III-IV, and extensive chronic GVHD in Haplo and UCB groups were 38.9% versus 54.2% (P=0.479), 2.8% versus 29.2% (P=0.004), and 11.7% versus 12.5% (P=0.906), respectively. The CI rates of nonrelapse mortality were significantly lower in Haplo group (0% versus 33.6%, P<0.001), while the relapse incidences were not different (18.3% versus 8.6%, P=0.272). The event-free survival (EFS) rates at 2 years (79.3±7.0% versus 54.2±10.2% %, P=0.034) and overall survival (OS) rates at 2 years (85.8±6.7% versus 65.7±9.9%, P=0.029) in Haplo and UCB groups were significantly different.Conclusion: In this study, the CI rates of nonrelapse mortality and acute GVHD III-IV was lower in Haplo group than in UCB transplants, which translates into a better EFS and OS rate in Haplo group. Our results suggest that haploidentical HSCT with PTCy using intensive PK monitoring, targeted busulfan-based myeloablative conditioning regimen is a safe and promising alternative option for patients with hematological malignancies who lack an HLA-matched donor. DisclosuresNo relevant conflicts of interest to declare.

Increased Risk of 100-Day and 1-Year Infection-Related Mortality in Haploidentical Stem Cell Transplantation Patients

Introduction:Haploidentical hematopoietic stem cell transplantation (HSCT) is a potentially curative intervention for various malignant and non-malignant hematological conditions. Its use has led to the near universal availability of donors, but major challenges compared to HLA-matched related donor (MRD) and HLA-matched unrelated donor (MUD) transplants still exist. Although the most frequently discussed complication of haploidentical HSCT is graft rejection or severe/fatal graft-versus-host disease (GVHD), infection remains a significant cause of morbidity and mortality compared to other forms of transplant.Methods:This was a retrospective, single institution study that analyzed the outcomes of 187 patients with various hematological diseases who received allogeneic HSCT with haplo donor transplants, MRD transplants, or MUD transplants from 2011-2018. Conditioning regimens included combinations of fludarabine, busulfan, cyclophosphamide, melphalan, antithymocyte globulin, and total body irradiation. GVHD prophylaxis included either the combination of cyclosporine, tacrolimus, and mycophenolate mofetil (MMF) or tacrolimus and methotrexate (MTX). All patients received anti-viral prophylaxis with acyclovir, anti-fungal prophylaxis with either an azole or echinocandin, and anti-bacterial prophylaxis with trimethoprim-sulfamethoxazole or levofloxacin if the absolute neutrophil count (ANC) was <500 cell/mm3. Statistical analysis was performed using the Fisher Exact Probability Test with p-values <0.05 deemed significant.Results:Of the 187 patients who underwent allogeneic HSCT, 45 (24%) of the transplants were from haploidentical donors and 142 (76%) from non-haplo donors (MRD and MUD). Amongst all patients, median time to neutrophil engraftment (ANC >500 cells/mm3) was 16 days (range 13-25 days). Acute GVHD was present in 41% of haploidentical patients and 42% of non-haploidentical patients (p >0.05). Rates of chronic GVHD were also similar between the two groups at 45% in haplo patients and 48% in non-haplo patients (p >0.05). The 100-day infection-related mortality rate following transplant was significantly higher in the haploidentical group at 9% compared to 1% in the non-haploidentical group (p = 0.03, Figure 1). In addition, the 1-year rate of infection-related mortality after transplant was also significantly increased at 16% vs. 4% in the haplo vs. non-haplo groups, respectively (p = 0.01, Figure 2). The proportion of patients who experienced bacterial and fungal infections over this time period was comparable between the two groups (41% vs. 42% for bacterial infections and 18% vs. 12% for fungal infections in haploidentical patients vs. non-haploidentical patients, p >0.05 for both) while the incidence rate of viral infections was significantly higher in the haplo group at 72% vs. 38% in the non-haplo group (p < 0.001). However, all cases of infection-related mortality were due to bacterial and fungal infections rather than viral with 27% of bacterial or fungal infections leading to patient death in haploidentical patients compared to 7% in non-haploidentical patients (p = 0.02, Figure 3).Conclusion:The results of our study showed that compared to non-haplo transplant recipients, patients who underwent haplo transplants had significantly increased risks of 100-day and 1-year mortality secondary to infections. This finding is supported by prior data demonstrating that there is a longer time to immune reconstitution, specifically of the T-cell subset and dendritic cell subgroup, in the haploidentical population (Chang et. al. Journal of Clinical Immunology 2011). Furthermore, our results showed that the increased risk of infection-related mortality is not due to higher rates of acute or chronic GVHD, implying that the risk may be due to haploidentical transplantation itself as opposed to increased amounts of immunosuppressive therapy. While there was a greater incidence rate of viral infections amongst haploidentical patients, no viral infections led to mortality in either transplant group. In contrast, despite similar rates of bacterial and fungal infections between haploidentical and non-haploidentical patients, these infections led to death more often in the haplo population. These findings are important in considering future approaches to infection prophylaxis and treatment in haploidentical transplant recipients. DisclosuresNo relevant conflicts of interest to declare.

No Influence of Peripheral Blood CD34+ and CD3+ Graft Cell Counts on Outcomes after Reduced-Intensity Conditioning Transplantation Using Post-Transplant Cyclophosphamide

IntroductionAlthough associated with a higher incidence of acute GVHD, peripheral blood stem cells (PBSC) are increasingly used for haploidentical allogeneic transplantation with post-transplant cyclophosphamide (PTCY). Data reporting whether or not the composition of the PBSC graft impacts outcomes of patients receiving PTCY are still scarce.Materials and MethodsThis retrospective study included all adults allografted in our department who received a PBSC allotransplant after reduced-intensity conditioning (RIC) with PTCY. Grafts originated from a matched or haploidentical donor and recipients received a Baltimore-based or a Clo-Baltimore (where fludarabine is replaced by clofarabine)-based RIC regimen. All patients received cyclosporine + mycophenolate mofetyl and PTCY as GVHD prophylaxis. CD34+ and CD3+ graft cell contents were considered to study their potential impact on the following outcomes: OS, DFS, GRFS, acute grade 2-4 and 3-4 GHVD and chronic GVHD, early immune reconstitution (IR, lymphocytes and monocytes counts at days+30 and +100 post-transplant, CD4+, CD8+, NK and B cells at day+100 post-transplant).ResultsBetween November 2013 and May 2017, 77 patients met the inclusion criteria. There were 48 males and 29 females with a median age of 58 years (range: 22-71) and a median follow-up for alive patients of 29.2 months (range: 8.4-53.2). Initial diagnoses were mainly acute myeloid (n=21) or lymphoid (n=6) leukemia, lymphoma (n=13), myelodysplastic syndrome (SMD, n=12), myelofibrosis (n=9). Thirty-eight patients were in complete remission at time of transplant (CR1 n=23; CR2 n=12, CR3 n=3) while 22 had active disease and 17 were in partial remission. Donors were sibling in 6 cases, matched unrelated (MUD) in 14, 9/10 mismatched unrelated in 1 and haploidentical in 56. Forty patients received a Baltimore RIC regimen and 37 a Clo-Baltimore RIC regimen. Analyses were performed in July 2018.Median infused CD34+ and CD3+ graft cell counts, based on recipients' weight, were 7.8 106/Kg (range: 1.45-14.24) and 22.23 107/kg (range: 1.95-66.75), respectively. All patients but three engrafted, the latter being 1 patient transplanted with a haplodonor, 1 with a MUD and 1 who died of infection during induction. Two-year OS, DFS and GRFS were 62.6% (52-74), 51.5% (40-63) and 36.6% (27-49), respectively. The incidences of grade 2-4 and 3-4 acute GVHD were 46.7% and 14.2%, respectively, while the incidence of moderate + severe chronic GVHD was 14%. Relapse occurred in 26 patients and non-relapse mortality (NRM) was 15.5%.Baltimore vs Clo-Baltimore patients shared similar median infused CD34+ and CD3+ graft cell counts and outcomes. The same was observed for patients allografted with a haplodonor or not, except for the incidence of grade 2-4 acute GVHD which was significantly higher for the haplo group at 57.1% vs 19% (p=0.006). This difference was first attributed to the higher CD3+ cell content infused in this group (median: 24.05 vs 18.85 107/kg, p=0.04). However, using the median of CD3+ cell graft content as threshold, the incidence of acute grade 2-4 GVHD was not different between low vs high groups when considering haplo patients. This suggests that it was rather the type of donor that did influence acute GVHD occurrence and that PTCY is of particular interest for GVHD prophylaxis when using matched donors.Partitioning the patients according to the median level of CD34+ cells, there was no difference in terms of 2-year OS (57.1% vs 60.7%, p=0.53), DFS (44.5% vs 55.6%, p=0.47) , GRFS (31.7% vs 44.3%, p=0.32), acute grade 2-4 (59% vs 39%, p=0.13) and 3-4 GVHD (17% vs 6.4%, p=0.29), and moderate + severe chronic GVHD (19.5% vs 20%, p=0.57). Similarly, partitioning patients according to median graft CD3+ cell content, outcomes were similar for 2-year OS (64.8% vs 55.8%,p=0.45), DFS (46.3% vs 55.8%, p=0.62), GRFS (36.3% vs 40.4%, p=0.63), acute grade 2-4 (44.7% vs 56.4%, p=0.42) and 3-4 GVHD (10.5% vs 15.3%, p=0.76), and moderate + severe chronic GVHD (14% vs 17.6%, p=0.91). Finally, early IR was not influenced by CD34+ and CD3+ graft cell contents.Conclusion: PBSC CD34+ and CD3+ graft cell contents have no impact on survivals, GVHD incidence nor early IR after a RIC allotransplant using PTCY as GVHD prophylaxis. As a consequence, there is no need to manipulate the graft nor cap the stem cells dose to be infused. These data have to be confirmed prospectively on a larger cohort of patients. DisclosuresGastinne:Millennium/Takeda: Honoraria. Moreau:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Hematopoietic stem cell transplantation without in vivo T-cell depletion for pediatric aplastic anemia: A single-center experience.

For young patients, HLA-MRD HSCT is the first-line treatment of SAA. However, due to China's birth control policy, few patients could find suitable sibling donors and HLA-MUD. More and more transplantation centers have used Haplo-D as the donor source for young adult and pediatric patients. However, studies with larger amount of pediatric patients are rare. We retrospectively analyzed the data of children with AA who were treated with allogeneic HSCT and compared the therapeutic efficacy of Haplo-HSCT and MRD/MUD group. A total of 62 patients were enrolled. Implantation was successfully performed in 58 patients. There was no significant difference in the time for reconstruction of hematopoietic function between patients in the two groups. Thirty-two had grade I-IV aGVHD with incidence of 51.61%. The incidence of aGVHD was 79.41% for patients in the Haplo-HSCT, significantly higher than that of 17.86% for patients in the MRD/MUD group (P<.01). However, the incidence of cGVHD was not significantly different between patients in the two groups (26.47% vs 10.71%, P=.09), the incidence of CMV infection was 28.57% and 52.94% for patients in the MRD/MUD and Haplo group, respectively, showing no significant difference (P=.053). The incidence of EBV infection was 47.06% for patients in the Haplo group and 28.57% for patients in the MRD/MUD group, showing no significant difference (P=.11). However, the 3- and 5-year cumulative OS and FFS rates showed statistically significant difference in the two groups, P=.012 and .045, respectively. Compared to Haplo-HSCT, MRD/MUD is more economic. In this study, we achieved good Haplo transplantation results. The incidences of cGVHD and CMV/EBV were not significantly different between Haplo group and MRD/MUD group. Although OS and FFS of the Haplo group were not as good as those of the MRD/MUD group, it is still acceptable as an alternative treatment under emergency.

The effect of donor source on outcomes after second allogeneic hematopoietic cell transplantation for relapsed leukemia.

7044 Background: There is no standard treatment for patients with leukemia who relapse after allogeneic stem cell transplant (HCT). A second HCT (HCT2) may be the only possibly curable option; however, this is performed in few patients. We hypothesized that patient and transplant characteristics, such as donor source will affect outcomes. Methods: We retrospectively evaluated adult patients who received a HCT2 for relapsed leukemia or MDS at a single institution between 2000-2016. 85 patients underwent a HCT2 with an unmanipulated graft from a matched related (MRD, n = 21), matched unrelated (MUD, n = 40), or haploidentical (haplo, n = 24) donor, preceded by either a reduced intensity (RIC) or myeloablative conditioning (MAC) regimen. Results: The median age at HCT2 was 50 yrs and the median time between transplants was 448 days. Patients had relapsed AML (n = 62), ALL (n = 12), and MDS (n = 10). The median length of follow up for survivors was 22.3 months (range 3.9-131) with 20 patients alive in June 2016. 65 patients died; 32 from relapse, 21 from infection, 7 from GvHD, and 5 from organ failure. 1-year OS from HCT2 was 38.6%. For patients with MRD, MUD, haplo donors, 1 year OS was 52.3%, 33.3%, and 34.6% (p = 0.72). 1-year DFS in the entire cohort, MRD, MUD, and haplo groups was 26.4%, 14.3%, 34.8%, and 25.3% (p = 0.45). 1-year TRM was 36.2% and not different across these groups (p = 0.80). Univariate analyses of OS, DFS, and TRM based on patient, disease, and transplant characteristics showed an association with RIC and worse OS and DFS (HR 2.0, 95% CI 1.2-3.3; and HR 1.9, 1.2-3.1). Having &gt; 1 year between transplants was associated with lower TRM (HR 0.38, 0.19-0.77). Traditional risk factors like age, presence of active disease at HCT2, shorter time between transplants, and using the same donor from the first HCT were not otherwise significantly associated with OS, DFS, or TRM. Conclusions: Outcomes after HCT2 did not differ based on donor source. MAC is associated with better OS relative to RIC (1yr OS 51% vs 23%, p &lt; 0.01), DFS (1yr DFS 37% vs 12%, p &lt; 0.01), with similar TRM (1yr TRM 30% vs 47%, p = 0.12). Based on these data, serious consideration is necessary before using RIC regimens for HCT2 in patients with relapsed leukemia.

SLAVIC, GERMANIC AND FINNISH-UGRIC POPULATIONS WERE INHABITATED IN CIRCUMPOLAR AREA IN PALAEOLITHIC

The calculation of genetic distances of 55 human populations belonging to four great human races considering loci of proteins, enzymes and blood groups, and construction the dendrogram of this populations distinguished some relationship of German, Slavic and Finnish-Ugric populations. So, Russians are in one subcluster with Poles, Iranians, Komi, Chuvashes, Udmurtians, Nentses and Ossetians. Germans are in one subcluster with Serbs, Moldavians, Hungarians, Croatians and Czechs. Greecs are in closeness with Slavic populations on this dendrogram, too.The calculation of genetic distances of 35 Slavic, Finnish and Germanic populations, and constructing the dendrogram confirmed this results. There were common migrations of this populations from places of first differentiation in Asia. In Europe German populations were migrated by another way than ancestors of Russians, which were migrated in Europe across North of Siberia. The ancestors of Germans probably migrated by the same way as Hunnu. Now are investigated settlements of ancient Caucasoids in Central Asia. The studing of mt DNA of rural Russian population in Yaroslavsky region discovered all haplogroups of Russians and even Caucasoids (H, W, I, U, X, T1). The last decoding of petrogliphs in Baical region discovered the presence of ancestors of Caucasoids in Siberia in paleolithic. Key Words: Human Populations, Genetic Relationship, Finnish-Ugric, Slavic, Germanic Populations, Genetic Distances, Anthropological Data

Hemorrhagic Cystitis in Haploidentical Hematopoietic STEM CELL Trasplant: Retrospective Study and Comparison with a NON-Haploidentical DONOR Transplant Group

IntroductionHLA-haploidentical hematopoietic stem cell transplant (Haplo HSCT) is a potentially curative strategy for patients lacking a HLA matched donor or a suitable unrelated donor. The use of post-transplant Cyclophosphamide (Cy) for GVHD prophylaxis and the particular characteristics of Haplo-HSCT can be linked to a higher risk of hemorrhagic cystitis (HC) and viral infections. In this context, our aim was to analyze HC in both haploidentical and conventional donor transplants in our center.Material and MethodsWe retrospective analyzed of 237 patients who received an HSCT in our center, between August-2012 and January-2016. We analyze the incidence of HC in the early post-HSCT period (6 months) and its characteristics in those patients receiving Haplo (n=36, 15%) and we compared it with a non-haploidentical donor transplant group from the same period (n=201, 85%).ResultsPatients' characteristics are summarized in table 1. Both groups are balanced, except for diagnosis due to the high proportion of Hodgkin lymphoma in Haplo group, conditioning regimen, and GVHD grade III-IV with a lower incidence in Haplo.Conditioning regimen in Haplo consisted of Fludarabine (30mg/m2x or 50mg/kg x 4days in RIC or MA regimen) and Busulfan (3.2 mg/kg x 2 in RIC or 3 days in MA). Post-HSCT Cy was used for GVHD prophylaxis in 94%. Median of days to reach more than 500x10^9 granulocytes and more than 20x10^9 platelets in Haplo group were 18 (13-30) and 23 (0-103) respectively.Hemorrhagic cystitis: Incidence of HC was 33% vs. 13% in conventional HSCT (p=0.03). Infectious etiology was documented in 84% of the Haplo recipients and 89% in conventional HSCT (p=0.87). In Haplo, HC was caused by BK/JC polyomavirus in 67% and adenovirus in 17%. Among conventional HSCT recipients, BK/JC was documented in 75% and adenovirus in 14% of HC. Viral infection was diagnosed by positive PCR in urine.HC appeared at a median of 65 days post-HSCT (5-557), without differences between Haplo and non-Haplo: 61 (5-423) vs. 67 (8-557).Treatment of HC consisted of hyper-hydration and spasmolytic drugs in 19 patients. Intravesical cidofovir was used in 7 and intravenous cidofovir was needed in 2 cases.Receiving an Haplo HSCT was associated with a higher risk of developing HC [OR 3.5 (95% CI 1.56-7.91); p=0.002]. We did not observed association between HC and conditioning regimen (p=0.18), receiving ATG (p=0.45) or presence of acute GVHD grade I-II (p=0.75) or grade III-IV (p=0.46). Haplo donor was the only variable with significant impact in multivariate analysis.ConclusionsIncidence of HC is higher in Haplo HSCT, being viral infections and not Cy toxicity, the main cause (polyomavirus BK/JC as the first cause). [Display omitted] DisclosuresMateos:Janssen, Celgene, Amgen, Takeda, BMS: Honoraria.

Favorable Immune Reconstitution Profile after Allogeneic Hematopoietic Stem Cell Transplantation with Post-Transplant Cyclophosphamide

Background: The administration of post-transplant high-dose cyclophosphamide (PTCy) has been shown to be an effective strategy for GvHD prophylaxis following allogeneic peripheral blood stem cell transplantation(PBSCT) from alternative donors. PTCy is toxic to allogeneic activated proliferating T lymphocytes, such as effector T cells. Conversely, it may not materially affect memory T cells.Methods: We evaluated immune reconstitution profile and transplant outcome in patients who received PBSCT with and without PTCy. PTCy was given on day +3 and +4 following haploidentical transplant (HAPLO), or only on day +3 following HLA-matched unrelated donor (MUD) transplant. No PTCy was given to patients with HLA-matched related donors (MRD). All patients received GvHD prophylaxis as tacrolimus (day +5 to +180) and MMF (day +5 to +35). Preparative regimens were myeloablative regimens (fludarabine/busulfan, fludarabine/TBI 12 Gy, or CY/TBI 12) in all patients except 4 patients (received fludarabine/melphalan). Immune reconstitution profile (IRP) was tested via serial flow cytometry analysis of peripheral blood lymphocytes after transplant were done on days +30, +100, and +180.Results: Data of 70 patients who underwent allogeneic PBSCT in our institution were analyzed in 3 groups; MRD (n=22), MUD (n=35), and HAPLO (n=13). The total cohort had 33 males (47%), and had median age of 52 years (range 20-70). All patients had hematological malignancy except one patient with HLH. The median duration of follow up was 6 months (range 1-17). The median day of neutrophil and platelet engraftment were 13, 12, 17 and 18, 15, 22 days for MRD, MUD and HAPLO groups respectively. The one-year overall survival of the whole group was 67% (95% confidence interval: 48-80) with no difference in OS among the 3 cohorts (log rank P value 0.4) (Figure 1). Lymphocyte and lymphocyte subset (T, B, NK) count recovery for MUD and HAPLO was significantly less (p<0.05) than MRD during the first month post-HSCT but these differences were statistically insignificant by day +60 and remained so through day +365. Recovery of both CD4+ and CD8+ naïve T cell (CD45RA+CD27+CD197+) population was generally slower for HAPLO patients during the first year and significantly less through day+ 180 for CD4+ T cells. As predicted, central memory (CD45RA-CD27+CD197+) CD4+ and CD8+ T cells remained proportionately equivalent at 40% and 28% respectively for all groups during the first year. The effector memory (CD45RA-CD27+CD197-) population was also proportionately consistent at 25% of total for both CD4+ and CD8+ subsets. Interestingly, the effector T cell population (CD45RA+CD27-CD197-) trended higher for all three recipient groups at each time point for both CD4+ and CD8+ populations increasing from 20% at one month to over 40% at one year.Conclusion: Post-PBSCT survival was not significantly different from alternative donor graft recipients and those that received MRD PBSCT. Lymphocyte recovery was impaired for the PTCy groups in the immediate post-PBSCT period but quickly recovered to that seen in MRD recipients. [Display omitted] DisclosuresSaad:Spectrum: Honoraria; American Porphyria foundation: Research Funding; Astellas: Research Funding; Alexion: Honoraria. Lamb:Incysus, Ltd: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding.

An analysis of transfusion support in haematopoietic stem cell transplantation – report from a centre in India

BackgroundTransfusion support in haematopoietic stem cell transplantation (HSCT) can be very demanding and challenging. The conditioning regimen, stem cell dose, donor type, presence of GvHD, infection all influence transfusion therapy in haematopoietic stem cell transplantation (HSCT). We retrospectively analysed the first 100 days transfusion requirements among HSCT recipients with haematological as well as non-haematological malignancies in our centre. Materials and MethodsTransfusion data were retrieved for 100 patients who had undergone HSCT over a period of two years. The HSCT recipients were divided into three groups: autologous, allogenic and haplo-identical. Allogenic group was subdivided into matched related donor (MRD) and matched unrelated donor (MUD). The allo and haplo groups were then classified on the basis of the ABO compatibility as major, minor, bi-directional and compatible. We analysed the mean requirement of blood components (RBC, RDP, SDP and FFP) within the first 100 days of HSCT in each category. Results and DiscussionHaematologic malignancies constituted 97% of the indications for HSCT. Allo-HSCT constituted 50% of the HSCT, of which 92% were MRD. Auto and haplo-HSCT constituted 40% and 10% respectively. Mean requirement for all products – RBC, SDP, RDP and FFP – was highest in the haplo category, followed by the allo category and then the auto HSCT category. The mean product requirement in the MUD category was significantly higher than in the MRD category (p < 0.05). The mean product requirement in the major and bidirectional ABO incompatible group was significantly higher as compared to the minor and ABO compatible group (p < 0.05).Hence our data may help transfusion medicine specialists to understand the transfusion requirement in stem cell transplant settings from developing countries like India. The average number of blood donors required for each group of stem cell transplant patients can also be roughly predicted from this study.

Unrelated cord blood compared with haploidentical grafts in patients with hematological malignancies.

Alternative donors, such as unrelated umbilical cord blood (UCB) and related haploidentical (haplo) donors, are more and more frequently searched for and used for patients who are candidates for allogeneic hematopoietic stem cell transplantation but are without a suitable related or unrelated donor. The aim of the current retrospective study was to compare the outcome of patients after haplo and UCB grafts prepared using a nonmyeloablative conditioning regimen. A total of 150 adult patients with high-risk hematologic diseases who underwent allogeneic hematopoietic stem cell transplantation from alternative donors at 2 centers (Paoli-Calmettes Institute [Marseille, France] and Humanitas Cancer Center [Milan, Italy]) were analyzed. Sixty-nine patients had haplo donors and 81 patients had UCB donors. The cumulative incidence of nonrecurrence mortality at 1 year was 23% in the UCB group versus 17% in the haplo group (P = .39). The incidence of grade 2 to 4 acute graft-versus-host disease and extensive chronic graft-versus-host disease in the UCB group versus the haplo group was 52% versus 29% (P = .05) and 12% versus 6% (P<.0001), respectively. The overall survival rate at 2 years was 45% in the UCB group (95% confidence interval [95% CI], 34%-56%) versus 69% in the haplo group (95% CI, 58%-80%) (P = .10). The progression-free survival rate at 2 years was 36% in the UCB group (95% CI, 25%-47%) versus 65% in the haplo group (95% CI, 53%-77%) (P = .01). The results of the current study suggest that for patients with high-risk hematological diseases without a related or unrelated donor, haploidentical transplants are a promising alternative option that deserves further investigation.

Presentation and Outcome of Zap 70 Deficiency

s / Biol Blood Marrow Transplant 21 (2015) S266eS321 S274 The identification of a donor has always limited the extent of allo HSCT. Recently it has been shown that a haploidentical donor could be a valid option to perform allo HSCT given adapted immunosuppression is used. Notably the use of PT-HDCy, after T-replete HSCT following reduced intensity (RIC) or non-myeloablative (NMAC) conditioning, has been associated with promising results. However little data exist concerning elderly population when this population is characterized by a lack of HLA matched sibling and a higher incidence of severe GVHD and non-relapse mortality. Using this strategy we transplanted 31 patients over the age of 55 years between 2010 and 2014 and compare their outcome with patients of the same age transplanted in the same period from a MRD or UD. 70% of the patients in haplo group were prepared with Flu-TBI 2gy (NMAC) (30% received Fludarabine-Busilvex based regimen without ATG) while all patients in other groups received the same RIC (Fludarabine (150 mg/m2) Busilvex (2 days) rabbit ATG (2 days)). Patients in haplo group received post graft immunosuppression with PTHDCy (50 mg/kg on D 3 and 4) followed with CSA and MMF while patients in other groups received either CSA starting on D1. Patients in the haplo group have a trend presenting higher comorbidities and more severe diseases (Table). A single graft failure related to donor anti-HLA antibodies were noted in haplo group. Median time to 0.5x109 ANC and 20x109platelets were respectively 21 (14-32) and 28 (14-52) days after haplo HSCT. Haplo and MRD HSCT patients presented with a similar NRM lower than UD patients while Haplo patients present a relapse rate intermediate between MRD and UD (table). Overall outcome after haplo do not differ from MRD transplant. There is a trend for better PFS after Haplo HSCT as compared with UD transplant (62% vs.41%; P1⁄40,14) (Figure 1). Progression-free and severe cGVHD-free survival was significantly better after haplo HSCT (62% vs. 35%; p1⁄40.03) (Figure 2). We conclude that T-replete Haplo HSCT after RIC and followed by PT-HDCy is associated with promising results notably as compared with UD HSCT. The low rate of severe aGVHD and cGVHD are likely to conduct to lower complications and better quality of life. The reduction of donor search duration and the absence of graft acquisition fees represent potential additional benefits. In this perspective, the place of Haplo HSCT in older patients should now be prospectively addressed.

Comparison of Haploidentical T-Replete HSCT Followed with Post-Transplant High Dose Cyclophosphamide (PT-HDCy) with Matched Related (MRD) or Unrelated (UD) HSCT in Patients in or after the 6TH Decade

s / Biol Blood Marrow Transplant 21 (2015) S266eS321 S274 The identification of a donor has always limited the extent of allo HSCT. Recently it has been shown that a haploidentical donor could be a valid option to perform allo HSCT given adapted immunosuppression is used. Notably the use of PT-HDCy, after T-replete HSCT following reduced intensity (RIC) or non-myeloablative (NMAC) conditioning, has been associated with promising results. However little data exist concerning elderly population when this population is characterized by a lack of HLA matched sibling and a higher incidence of severe GVHD and non-relapse mortality. Using this strategy we transplanted 31 patients over the age of 55 years between 2010 and 2014 and compare their outcome with patients of the same age transplanted in the same period from a MRD or UD. 70% of the patients in haplo group were prepared with Flu-TBI 2gy (NMAC) (30% received Fludarabine-Busilvex based regimen without ATG) while all patients in other groups received the same RIC (Fludarabine (150 mg/m2) Busilvex (2 days) rabbit ATG (2 days)). Patients in haplo group received post graft immunosuppression with PTHDCy (50 mg/kg on D 3 and 4) followed with CSA and MMF while patients in other groups received either CSA starting on D1. Patients in the haplo group have a trend presenting higher comorbidities and more severe diseases (Table). A single graft failure related to donor anti-HLA antibodies were noted in haplo group. Median time to 0.5x109 ANC and 20x109platelets were respectively 21 (14-32) and 28 (14-52) days after haplo HSCT. Haplo and MRD HSCT patients presented with a similar NRM lower than UD patients while Haplo patients present a relapse rate intermediate between MRD and UD (table). Overall outcome after haplo do not differ from MRD transplant. There is a trend for better PFS after Haplo HSCT as compared with UD transplant (62% vs.41%; P1⁄40,14) (Figure 1). Progression-free and severe cGVHD-free survival was significantly better after haplo HSCT (62% vs. 35%; p1⁄40.03) (Figure 2). We conclude that T-replete Haplo HSCT after RIC and followed by PT-HDCy is associated with promising results notably as compared with UD HSCT. The low rate of severe aGVHD and cGVHD are likely to conduct to lower complications and better quality of life. The reduction of donor search duration and the absence of graft acquisition fees represent potential additional benefits. In this perspective, the place of Haplo HSCT in older patients should now be prospectively addressed.

New insights into the taxonomy of the skittering frog Euphlyctis cyanophlyctis complex (Schneider, 1799) (Amphibia: Dicroglossidae) based on mitochondrial 16S rRNA gene sequences in southern Asia

The Skittering frog ( Euphlyctis cyanophlyctis ) is considered to be a species complex distributed in southern and southeastern Asia. Genetic diversity and taxonomic status of populations across their ranges is unclear and existence of several cryptic species is expected. In this study we used sequence variation in the mitochondrial 16S ribosomal RNA gene to elucidate the taxonomic status of Iranian populations of E. cyanophlyctis and compare their genetic diversity and divergence to populations from the Indian subcontinent. Phylogenetic analysis indicated that the populations of E. cyanophlyctis from Iran, Bangladesh-Assam (northeastern India), southern India, and Sri Lanka are partitioned into different clades. At least four different haplogroups were detected which are here proposed to be considered as allopatric cryptic species. The sedimentation of the Helmand River into the Sistan depression during the Neogene and subsequent formation of dry land barriers are proposed to have caused the Iranian populations of skittering frogs to be disconnected from those of the Indian subcontinent, resulting in differentiation of these lineages. In addition, some populations from southern India and those from Sri Lanka that were previously recognized as E. cyanophlyctis belong to E. mudigere . A preliminary investigation on the genetic diversity of the populations from southeastern Iran highlights the low genetic diversity among these populations.

Differences in Natural Killer(NK) Reconstitution Between Unmanipulated Haploidentical and HLA Identical Stem Cell Transplantation and Relationship with Citomegalovirus and Graft Versus Host Disease (GVHD). Experience in One Centre in 22 Patients.

Introduction: It´s well known that NK cells exert an important role in postransplant immune reconstitution. Their maturation process through the contact with recipient´s bone marrow stromal cells is crucial for the development of their functional capacities. Previous studies showed the relevance of NK alloreactivity in relapse prevention and the influence of NK subpopulations and expression of activating receptors on CMV infection control, antitumor effects, and graft versus host disease (GVHD). Unmanipulated Haploidentical (Haplo) transplantation with postrasplant cyclophosphamide (Cy) is an emerging alternative for patients (pts) with no identical sibling donor with encouraging results. We previously reported preliminary data of NK cell reconstitution in 7 pts in Haplo setting. Our aim is to contrast our previous data in 22 pts comparing with conventional HLA-identical (HLAid) Stem Cell Transplantation (SCT) and to analyse the relationship between NK reconstitution and CMV reactivation and GVHD.Methods: 22 pts received an Haplo SCT and 7 pts an HLAid SCT in Gregorio Marañon Hospital between January 2013 and April 2014. Peripheral blood was used in all cases. Conditioning regimen comprised fludarabine (Flu), Cy and busulfan (Bux) for Haplo and Flu/Bux or Flu/Melphalan for HLAid SCT. Prophylaxis for GVHD consisted of high dose Cy on +3, +4, cyclosporine (CsA) A and mycophenolatemofetil for Haplo and CsA/Methotrexate for HLAid. Table1 show patients characteristics. For analysis of NK reconstitution and receptor expression multi-colour flow cytometry on FC500 and Navios Beckman Coulter® was used. Total NK cells, CD56 intensity and expression of NKG2A, NKp30, Nkp46 and NKG2D was studied at +15, +30, +60, and +90. For comparison between the two groups Mann–Whitney U-test was used.Results: Median NK cells/mm3 on +15 and +30 were significantly lower on Haplo than HLAid group ( 0 (0-5.5) and 28.5 (12.2-96.5) vs 69.5 (55-134) and 276 (151-422); p<0.05), being similar on + 60 and +90 (86 (49.5-158) and 147 (85-204.5) for Haplo vs 105 (39.2-162.5) and 117 (82-197) for HLAid; p ns). In Haplo pts NK cells reached normal levels on +60, while only 6/22 (27%) on +30. As previously reported NK high percentages of immature CD56bright (CD56b) cells and high expression of immature receptor NKG2A appears on +30, decreasing on +60 and +90 (CD56b 80% (72.5-88.5), NKG2A 88% (80-94) on +30, 39% (25-49) and 73% (62.2-86.7) on +60, 34% (23-43) and 69% (54.7-77.5) on +90. Compared with HLAid patients, the percentage of NKb cells was significantly higher (p<0.05) on Haplo group on +30, +60 and +90 and expression of NKG2A was also higher on +15, +30 and +60 (p<0.05). Interestingly, expression of activating receptors NKP46 and NKG2D linked to NK maturation are only significantly decreased in Haplo group comparing with HLAid on +15 (p<0.05), with appropriate expression and no differences on +30, +60 and +90. In fact, expression of NKP46 tended to be higher in Haplo on +30 (81% (62.5-90) vs 61% (42-71)), with no statistical significance (p 0.06). NKP30 had a low expression, similar in the 2 groups. In Haplo pts, no differences were found in total NK cell between pts with and without CMV reactivation at any time. Patients with acute GVHD had lower NK cells/mm3 at +30 (21.5 (10.7-35) vs 122 (21.7-260.7) and +60 (75(46-137) vs 156 (51-258); p 0.1), but statistical significance was not reached. Proportion of CD56b and NKG2A expression did not show any difference in pts regarding presence of CMV reactivation or GVHD.Conclusions: After Haplo SCT with postransplant Cy NK cell reconstitution seem to be delayed comparing with HLAid sibling SCT, reaching normal levels at +60. As previously reported, we confirm in our series that NK maturation also show a different pattern. In Haplo setting NK cells remains in an immature phenotype with high proportion of NK CD56b and expression of NKG2A much longer than in HLAid pts. Interestingly activating receptors expression, normally linked to maturation is only lower in Haplo pts in +15, but it is similar in both SCT types by day +30 and later, what should translate in appropriate cytotoxic capacity. In Haplo group, those patients with and without CMV reactivation had similar NK cell reconstitution. Patients with GVHD seem to have an impaired early NK reconstitution, but this fact needs to be contrasted.Acknowledgments: Fundación Mutua Madrileña. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.