HLA Identical Research Articles

Reduced Relapse and Improved Survival in Chemosensitive Hodgkin Lymphoma Patients Undergoing Haploidentical Related Donor Compared to HLA-Identical Donor Transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) represents a potential curative option for patients with relapsed or refractory Hodgkin's lymphoma (RR HL).Allo-HSCT from haploidentical donor (haplo-HSCT), when HLA identical donor is not available, is considered a good alternative. Using haploidentical donors, the immunological activity against HL seems to be particularly high. In this retrospective study, we analysed the results obtained using HLAid donors or haploidentical donor in RR HL patients.Inclusion criteria were allo-HSCT performed during the same period (2010-2014); chemosensitive disease at allo-HSCT (complete + partial remission); T-cell replete haplo-HSCT using post-transplantation Cy. Haplo-HSCT were performed in 3 Centers (Humanitas Research Hospital, Rozzano; Ospedale San Martino, Genova; Institut Paoli Calmettes, Marseille, France) and HLA identical transplantation, both from related or unrelated donor, in centers from the Gruppo Italiano Trapianto di Midollo e cellule staminali periferiche (GITMO). 65 patients received Haplo-HSCT and 133 HLA-identical (HLA-id) transplantation. The institutional review board of each center approved the study. Patients and transplant characteristics were reported in Table 1. The median follow up was 30.6 months (range 0.2-74.1).Myeloid engraftment was slower in haplo group than HLAid group (20 days vs 14 day). In the haplo group, 2 out 3 patients had graft failure because of donor specific antibodies (DSA), and 1 patient dead from pneumonia before engraftment.In the Haplo and HLA-id group, the incidence of grade 2-4 acute GVHD was 15% vs 16% (p= 0.9) and chronic GVHD were and 18% vs 32% (p 0.06), respectively.For the whole cohort, the 2-year PFS, OS, relapse incidence (RI), and 1y-NRM were 45%, 66%, 38%, and 14%, respectively. The PFS, OS, and RI were significantly better in patients in CR compared to those in PR (55% vs 29% p= 0.001, 74% vs 55% p= 0.03, 27% vs 55% p<0.001, respectively), whereas the 1-year NRM was similar (15% vs 16% p= 0.9). After Haplo-HSCT and HLA-id HSCT, 2-year PFS was 63% vs 37% (figure 1A, p= 0.03), the 2-year OS was 67% vs 63% (p= 0.6), and the 1-year NRM was 13% vs 15%, (p= 0.9), respectively. The 2-year RI was significantly lower in the haplo group (figure 1B, 24% vs 44%, p= 0.008). We analyzed the clinical outcome in specific sub-groups of patients, coupling disease status and donor. Patients in CR receiving haplo-HSCT showed a significantly better 2-year PFS and lower 2-year RI compared to those allografted by HLA-id donor (figure 1C75% vs 47%, p<0.001 and 11% vs 34%, p<0.001, respectively). No statistically differences were founded in terms of OS and NRM. In PR patients, we found a similar outcome between patients receiving haploidentical donor or HLAid donor. The 2-year PFS was 44% vs 22%, p<0.001; and the 2-year RI was 44% vs 60%, p<0.001 (figure 1D).In multivariate analysis, donor type (haplo vs HLA-id HR 0.51, p<0.001) and disease status before transplantation (CR vs PR HR 0.37, p= 0.014) were independent predictors of PFS as well as they predict the risk of relapse (donor type HR 0.37, p<0.001; disease status, HR 0.43, p= 0.006). Disease status at transplantation and age (as continuous variable) were independently associated to OS (CR vs PR HR 0.57, p= 0.02; age HR 0.04, p= 0.006).This analysis suggested that haplo-HSCT using T-cell replete stem cells and PT-Cy is more effective than HLA-id donor because of a significant reduction of relapse risk in chemosensitive RR HL patients, challenging the question of donor choice. However, prospective comparative studies are needed to draw definitive conclusions. [Display omitted] DisclosuresCiceri:GSK: Other: B-thalassemia gene therapy was developed by Fondazione Telethon and Ospedale San Raffaele and has been inlicenced by GSK that provides funding for the clinical trial, Research Funding. Specchia:Novartis: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Incyte: Consultancy, Honoraria. Carlo-Stella:ADC Therapeutics: Research Funding. Rambaldi:Novartis, Amgen, Celgene, Sanofi: Other: Travel, Accomodations, Expenses; Novartis, Roche/Genentech, Amgen, Italfarmaco: Consultancy. Santoro:Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees. Corradini:Celgene: Honoraria; Roche: Honoraria; Janssen: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Sanofi: Honoraria; Amgen: Honoraria; Gilead: Honoraria.

Risk Factors and Outcomes According to Age at Transplant with an HLA Identical Sibling for Sickle Cell Disease

Background: Hematopoietic stem cell transplant (HSCT) from an HLA identical (HLAid) sibling donor is a well-established curative therapy for sickle cell disease (SCD). However, the ideal age to perform HSCT in SCD patients remains controversial. We report the outcomes after HLAid sibling HSCT for SCD according to patient's age at the time of HSCT as well as their pre-transplant characteristics.Methods: We retrospectively analyzed 727 HLAid sibling HSCTs performed between 1986 and 2015 in 98 EBMT centres. Patients were divided in three groups according to their age at the time of HSCT: <5 year-old (n=176): group 1, 6-15 year-old (n=431): group 2 and >15 years old (n=120): group 3. Primary endpoint was probability of 3-year overall survival (OS) according to age group.Results: Median follow-up was 46 (range: 0.5-346) months. Median age at HSCT was 4 (range: 0.9-5) years in patients <5 years, 10 (range: 6-14) years in patients 6-15 years and 17 (range: 15-39) years in patients >15 years. Gender distribution did not significantly differ among the three groups. The most common SCD genotype was homozygous (SS) in the three groups (95% vs 92% vs 84%, p=0.004). Positive cytomegalovirus (CMV) serology was less frequent in group 1 (63% vs 79% vs 83%, p<0.001. Also, patients in group 1 were less treated with hydroxyurea (37% vs 60% vs 77%, p<0.001), received less than 20 red blood cell units transfusions (32% vs 43% vs 58%, p=0.002) and presented less than 3 SCD complications before HSCT (11% vs 19% vs 39%, p<0.001). For all age groups, vaso occlusive crisis (VOC), acute chest syndrome (ACS) and cerebral vasculopathy were the most reported SCD complications, and the main indications for HSCT were VOC, cerebral vasculopathy, ACS and nephropathy.The proportion of patients with Karnofsky performance status (KPS) <80 did not differ between groups. Graft source distribution was bone marrow (BM) in 74%, cord blood (CB) in 23% and peripheral blood (PBSC) in 3% of cases in group 1; BM in 85%, CB in 11% and PBSC in 4% of cases in the group 2; BM in 79%, CB in 1% and PBSC in 20% of cases in group 3 (p<0.001). Conditioning regimen was myeloablative in 97% of cases in group 1, 96% in group 2 and 83% in group 3 (p<0.001), and included in vivo T cell depletion, mostly antithymocyte globulin (ATG), in 74%, 86% and 90% of the cases, respectively (p<0.001). In all groups, graft versus host disease (GvHD) prophylaxis was mainly cyclosporine- A with methotrexate±mycophenolate mofetil. ABO and gender match between donor and recipient did not significantly vary among groups.Neutrophil engraftment at day +60 was 96%+1 in the first group, 98%+1 in the second group and 95%+2 in the third group (p=0.009). Four patients in group 1, 10 patients in group 2 and 6 patients in group 3 had primary graft failure. The first group experienced less acute GvHD (aGvHD) within 100 days after HSCT (9%+2 vs 18%+2 vs 17%+4, p=0.022) and less chronic GvHD (cGvHD) within 3 years after HSCT (9%+2 vs 12%+2 vs 20%+4, p=0.006). Three-year OS was significantly better in group 1 (99%+1 vs 95%+1 vs 88%+3, p<0.001) as well as 3-year event free survival (EFS) (96%+2 vs 92%+1 vs 84%+4, p=0.001). In a subset of patients with available chimerism data (n=405), in group 1 and group 2 65% were full donor, 32% mixed chimeras and 3% autologous reconstitution whereas in group 3 46% were full donor, 49% mixed chimeras and 5% autologous reconstitution. A univariate risk factor survival analysis was performed for group 3 (only group with sufficient events for analysis), but no patient, donor or HSCT risk factors influencing OS were identified.Conclusion: Patients transplanted at a young age have a better 3-year OS and 3-year EFS, with lower incidence of aGvHD and cGvHD. These findings outline the importance of early referral to HSCT for SCD patients. Strategies to further evaluate pre HSCT, HSCT and donor factors that may influence survival and adverse outcomes could help improve HSCT results. Disclosuresde la Fuente:Jazz Pharmaceuticals: Honoraria; bluebird bio: Consultancy; HCA: Consultancy. Bader:Novartis, Medac, Amgen, Riemser, Neovii: Consultancy, Honoraria, Research Funding.

Lessons From Pancreas Transplantation in Type 1 Diabetes: Recurrence of Islet Autoimmunity.

Type 1 diabetes recurrence (T1DR) affecting pancreas transplants was first reported in recipients of living-related pancreas grafts from twins or HLA identical siblings; given HLA identity, recipients received no or minimal immunosuppression. This observation provided critical evidence that type 1 diabetes (T1D) is an autoimmune disease. However, T1DR is traditionally considered very rare in immunosuppressed recipients of pancreas grafts from organ donors, representing the majority of recipients, and immunological graft failures are ascribed to chronic rejection. We have been performing simultaneous pancreas-kidney (SPK) transplants for over 25 years and find that 6-8 % of our recipients develop T1DR, with symptoms usually becoming manifest on extended follow-up. T1DR is typically characterized by (1) variable degree of insulitis and loss of insulin staining, on pancreas transplant biopsy (with most often absent), minimal to moderate and rarely severe pancreas, and/or kidney transplant rejection; (2) the conversion of T1D-associated autoantibodies (to the autoantigens GAD65, IA-2, and ZnT8), preceding hyperglycemia by a variable length of time; and (3) the presence of autoreactive T cells in the peripheral blood, pancreas transplant, and/or peripancreatic transplant lymph nodes. There is no therapeutic regimen that so far has controlled the progression of islet autoimmunity, even when additional immunosuppression was added to the ongoing chronic regimens; we hope that further studies and, in particular, in-depth analysis of pancreas transplant biopsies with recurrent diabetes will help identify more effective therapeutic approaches.

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.

Haploidentical stem cell transplantation (Haplo-HSCT) with nonmyeloablative conditioning regimen (NMAC) and postinfusion cyclophosphamide in advanced non-Hodgkin lymphoma (NHL) patients.

7039 Background: In patients lacking HLA identical (HLA-id) donors, haploidentical (Haplo) donors is increasingly considered as a valid alternative stem cell source.The introduction of post-infusion Cyclophosphamide (Cy) as prophylaxis for immunological complications using T-cell replete graft is one of the most usual strategy. However, efficacy is still a matter of debate. Here we reviewed the outcome of 28 consecutives Haplo-HSCT patients with advanced NHL that we compared to an historical control cohort of patients transplanted from HLA-id donors. Methods: 28 Haplo-HSCT were performed between 04/06/2010 and 27/09/2013. Diagnoses were aggressive NHL in 22 patients and low-grade NHL in 6. Median age was 48 years (19-67). At transplant, 64% were in complete remission, 29% in partial remission and 7% in stable disease. These 28 patients were fully matched to 61 HLA-id patients. Conditioning regimen varied according to donor source. Haplo-HSCT patients received a NMAC associating of Fludarabine (150mg/m² to...

114-P: REGULATORY T AND B CELL CIRUITS IN TOLERANT HLA-IDENTICAL KIDNEY TRANSPLANT RECIPIENTS AND NORMAL VOLUNTEERS

In an HLA Identical (HLA-id) renal transplant (RT) tolerance trial using donor hematopoietic stem cells, alemtuzumab induction, and temporary maintenance immunosuppression (IS), primarily with sirolimus, 6 of the first 12 recipients achieved non-chimeric tolerance (IS-free for over 1 year without rejection in biopsies at >3 years post-op). We assessed the phenotypic and functional T and B regs present in these tolerant vs. non-tolerant recipients compared with T and B regs generated in vitro in MLRs of normal volunteers. We tested the generation of Bregs (CD19 + IL10 + ) and Tregs (CD4 + CD25 high CD127 − FOXP3 + ) interactively in MLR both in HLA-id tolerant recipients and normal volunteers. All recipients developed significantly higher percentages of phenotypic Treg and naïve B cells (containing putative Bregs) post-RT. In tolerant vs. non-tolerant recipients, unselected post-RT PBMC (>18 months) (vs. pre-RT PBMC) added into recipient donor specific MLRs, augmented of newly generated Bregs and Tregs (P < 0.02; n=5 thus far tested). In normal laboratory volunteers, i mmunoselected CD127 − CD4 + CD25 + Tregs generated in 7-day MLRs, added as third component modulators, inhibited proliferation of fresh MLR readouts from the same pairs and augmented the generation of new responder Bregs by 5-10 fold. This was in contrast to PBMC modulator controls (n=12). The Bregs in turn could secondarily generate additional Bregs and Tregs. [figure1] These results suggest that long-lasting functional Treg and Breg circuits are generated in tolerant non-chimeric HLA-id recipients. Such assays might be used to discriminate between tolerant and non-tolerant recipients.

A simplified method for screening siblings for HLA identity using short tandem repeat (STR) polymorphisms

Identifying an HLA-matched sibling donor for hematopoietic stem cell transplantation (HSCT) is time-consuming and expensive, and often limited by reimbursement caps imposed by insurance providers. To improve the effectiveness and efficiency of screening for HLA-matched siblings, we developed an assay for determining HLA identity using a panel of nine informative short tandem repeat (STR) loci located throughout the HLA complex. The STR panel was assessed for accuracy in identifying HLA-matched siblings in 88 family workups comprising a total of 132 related donor and recipient typing comparisons. All sibling pairs with identical STR alleles were also HLA identical. Of the 48 pairs mismatched at one or more STR alleles, all were genotypically HLA non-identical at one or more loci. The sensitivity and specificity of STR analysis for identifying HLA-matched siblings were 91% and 100%, respectively. Three false negatives occurred due to an STR mutation or possible HLA-DPB1/DQB1 recombination. Additionally, STR genotyping provided additional information allowing determination of the extent of HLA identity in families where HLA haplotype inheritance was ambiguous, due to extensive homozygosity or shared parental haplotypes. The HLA STR assay is a reliable and rapid test that can be used to inexpensively screen potential sibling donors for HLA identity.

LOW Tranplant Related Mortality and LOW GRAFT Rejection After Related Haploidentical STEM CELL Transplantation (HAPLO-SCT) Prepared with NON Myeloablative CONDITIONING REGIMEN (NMA) and Posttransplant Cyclophosphamide for Advanced Lymphoid Malignancies.

AbstractAbstract 3031 Introduction:The use of hematopoietic stem cells from partially matched family donors has become an alternative transplant option for patients with no HLA identical donor available. It might be even a first choice, especially in advanced hematological maligancies, because of the presumed stronger graft versus tumor effect relied to the partial HLA identity. However, haplo-SCT is associated with high risk of graft rejection (GR) and severe graft versus host disease (GvHD), especially after non NMA. High dose posttransplant Cyclophosphamide (Cy) has been shown to prevent GvHD and GR. Aim:This retrospective analysis report the outcome of 15 patients (pt) using posttransplant Cy after a NMA in our center. Results:Fifteen adult pt (Male=9) with high risk lymphoid malignancies for whom a HLA matched related or unrelated donor were not available, underwent haplo-SCT from February 2011 to June 2012. The median pt age was 41years (y) (range, 20–60). Diagnosis were Hodgkin Lymphoma in 5 pt, Non Hodgkin Lymphoma in 4 pt, Chronic Lymphatic Leukemia in 2 pt, Multiple Myeloma in 2 pt and Acute Lymphoblastic Leukemia in 3 pt. All pt were heavily pretreated with a median of 3 or more chemotherapy regimens including failure of previous autologous (12pt) or allogeneic transplantation (3pt). At time of transplant 9pt (60%) were in complete remission (CR1=6, CR2=3). The NMA consisted in Fludarabine 30mg/m2 iv on days -6 to -2, Cyclophospamide 14.5mg/kg iv from days -6 and -5 and Total Body Irradiation 200cGy on day -1. For Graft versus Host Disease prophylaxis all pt received postransplant Cy 50mg/kg iv on days + 3 and +4 with Mesna. One day later, all pt started with Cyclosporine (CSA) 3mg/kg/day and Mycophenolatemofetil (MMF) 15mg/kg/day and Filgrastim 5ug/kg/day until neutrophil recovery. MMF was stopped at day+35 and CSA was given until day +180 in the absence of GvHD. Ten pt (67%) received bone marrow (BM) and 5 pt (33%) G-CSF mobilized peripheral blood stem cells (PBSC) as graft source. All donors were HLA haploidentical first degree family donors (Male=8) including brothers (7), sisters (2), mothers (4) and son (1). Median donor age was 49 y (range, 23–66). Pt had HLA typing at the allele or antigen level (A, B, Cw, DRB1, DQ) whereas 8 pt were mismatched at 5 loci, 1 pt at 4 loci, 4 pt at 3 and 2 pt at 2 loci. BM grafts contained a medium of 2×106/kg CD34+ cells and 22×106/kg CD3+ cells. PBSC grafts contained a medium of 6×106/kg CD34+ cells and 298×106/kg CD3+ cells. The engraftment rate was 93%, with a median time to neutrophil recovery (>500 G/l) of 20.5 days (range, 14–26) and to platelet recovery (>20 000 G/l) of 28.5 days (range, 14–41). Compared to BM recipients, pt receiving PBSC experienced faster neutrophil [(17 days (range, 14–23) vs 21 days (range, 18–26), p=0.04] and platelet recovery [(23 days (range, 14–30) vs 30 days (range, 23–41), p=0.04)]. One pt with ALL did not engraft and died at day +40 for infectious complication. One pt died of treatment related mortality with a cumulative incidence of 7% [96%CI (0–20)]. Two pt developped acute GvHD grade 2. No chronic GvHD was observed in pt surviving beyond day 100. Four pt exerienced relapse or progression of the underlying disease. After a median follow up of 197 days (range, 40–518) the actuarial overall survival and event-free survival at 2 years were 87% [95% CI (70–100)] and 51 % [95% CI (16–85)], respectively. Conclusion:NMA haplo-SCT with postransplant Cy in pt with advanced lymphoid malignancies is associated with low NRM, low acute GvHD and low graft rejection. However, better disease control in selected pt is needed to overcome early relapse or progression. Even if follow-up is short, PBSC seems to be an promising option to bone marrow as stem cell source. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Risk Factors Analysis of Outcomes of Related Cord Blood Transplantation in Children with Hematological Malignancies.

Overall survival of HLA identical bone marrow are comparable to umbilical cord blood transplantation (RCBT) in children with malignant and non-malignant disorders, however there is no data analysing risk factors of outcomes in a large series of children with malignancies given a RCBT. Thus, we have studied 128 RCBT performed from 1990 to 2005 and reported to Eurocord. The median age was 5 years (1–20 y); weight 19kg (8–56); and the median follow up was 55 months (2–162). Most of the children had leukemia [ALL (n=73), AML or MDS (n=33) CML (n=13)] and 9 children had other malignancies (4 non-Hodgkin lymphoma, 4 solid tumors,1 histiocytosis). Previous autologous transplant was given to 11%. At transplant, 22 children (17%) were transplanted in early stage of the disease; 58 (45%) in intermediate and 47 (37%) in more advanced phase. Median time from diagnosis to transplantation was 19 months (4–105). The donor was HLA identical in 104 cases (81%) and HLA incompatible in 24 cases (1 antigen=3, 2 ag=10, 3 ag=11). TBI based regimen was used in 52% and as GVHD prophylaxis CSA alone in 59%. The median number of nucleated cells at collection was 4.8x107/kg (1–19x107) and at infusion was 4x107/kg (0.6–18). Most of cord blood units were banked at the local institution where the transplantation took place.Results: median days of neutrophils and platelets recovery were 23 (8–49) and 38 (12–165) days, respectively. Estimate probability of neutrophils recovery at day 60 was 89±3% and 180-day platelet recovery was 81%. In multivariate analysis for neutrophil recovery, HLA identity was the most important factor associated with increased probability of recovery (93%vs 72%, adjusted p=0.004). There was a trend of better recovery for patients receiving a higher cell dose (90%vs 85%, adjusted p=0.06). Acute GVHD (II-IV) was observed in 24 patients (II=23, III=5, IV=2). HLA compatibility and higher cell dose were associated with decreased incidence of acute GVHD. In fact children receiving an HLA incompatible graft had an incidence of 46% compared to 17% of the remainders (p<0.001). Chronic GVHD was observed in 12% of patients at risk. At 5 years relapse incidence was 44% for patients transplanted in early phase of the disease, 54% in intermediate and 65% for those in advanced phase (p=0.04). At 5 year transplantation related mortality was 21%, overall survival was 48% and disease-free survival (DFS) was 40%. In a multivariate analysis for DFS, HLA compatibility (p<0.001), female gender (p=0.03), younger children (<5 years)(p=0.05) and children transplanted in remission (p=0.02) were factors associated with increased DFS. In fact, 5 y-DFS of children transplanted with an HLA compatible donor was 46% compared to 13% in those transplanted with an incompatible relative. In conclusion, with these promising results, banking of a related HLA identical unit should be encouraged when possible. HLA compatibility plays an important role for neutrophils recovery, GVHD and DFS after RCBT.

Acute GVHD May Play a Role in Preventing Relapse Following Reduced Intensity Allografts for Acute Myeloid Leukemia.

The role of reduced intensity allografting in the treatment of patients (pts) with acute myeloid leukemia (AML) and the role that graft versus host disease (GVHD) plays in preventing relapse in this setting is unclear. While more pts may survive the initial period following allografting in comparison to those receiving full intensity transplants, the risk of relapse may be greater, particularly in those not in remission at the time of transplantation. Here we report the results of allogeneic transplants following a reduced intensity conditioning (RIC) regimen given to 158 consecutive pts with AML. All were all conditioned with an identical regimen containing Cyclophosphamide at 120mg/kg iv over 2 days (days −3 and −2) followed by a single dose of total body irradiation at 550cGy on day −1. HLA-identical (HLA-ID) siblings donated cytokine mobilized peripheral blood (PB) to 68 recipients and unrelated donor (UD) bone marrow (BM) was used for 90 patients. GVHD prophylaxis consisted of single agent cyclosporine (CSP) for recipients of HLA-ID allografts and CSP, methotrexate, and methylprednisolone in recipients of UD BM. The median age of recipients was 44 years (range 6–70), with 74 males and 84 females. 43 pts were in CR1, 47 in CR2 or 3, and 68 had relapsed or refractory disease. The majority of UD BM recipients were serologically identical with their donors at 6/6 antigens. There were no graft failures in either group.The median follow-up in survivors was long at 1903 days (range 938–2757). Overall survival (OS) was evaluated in relation to the development of any grade of acute GVHD. There were no significant differences in the incidence of grade 2–4 (30+/− 6%) or grade 3–4 (7+/−3%) acute GVHD in the HLA-ID PB or UD BM groups. Since OS was not significantly different between CR1 and CR2 pts, the results were pooled. The Kaplan-Meier (KM) estimate of 3 year OS in UD BM pts in CR was 45+/−9% in those with no acute GVHD compared to only 25+/−10% with any grade of acute GVHD (p=0.24). In recipients of HLA-ID PB who were in CR, 3 yr OS was 39+/−12% without acute GVHD and interestingly, 54+/−10% with acute GVHD. UD BM recipients not in remission at the time of transplant had dismal outcomes with or without acute GVHD, with less than 5% OS. No recipients of HLA-ID PB with active disease at the time of transplant remained alive if they did not develop acute GVHD versus 19+/−10% if they did (p=0.17).These data obtained in a large group of homogeneously treated pts suggest that acute GVHD may play an important role in preventing relapse after RIC and HLA-ID sibling PB transplantation. Following UD BM, acute GVHD appears to adversely affect OS. RIC should not be proposed in the unrelated donor setting if pts with AML are not in remission. Future efforts aimed at harnessing graft versus leukemia effects in the HLA-ID setting following RIC may lead to improvements in OS and are clearly warranted.

Reduced Intensity Allografts for Acute Myeloid Leukemia: Defining the Role of Conditioning and Donor Alloreactivity.

The role of reduced intensity allografting in the treatment of patients with acute myeloid leukemia (AML) is unclear. While more patients may survive the initial period following allografting in comparison to those receiving full intensity transplants, the risk of relapse may be greater, particularly in patients not in remission at the time of transplantation. Here we report the results of allogeneic transplants using either cytokine mobilized peripheral blood (PB) or bone marrow (BM) following a reduced intensity conditioning (RIC) regimen. 131 patients with AML were all conditioned with an identical regimen containing Cyclophosphamide at 120mg/kg iv over 2 days (days −3 and −2) followed by a single dose of total body irradiation at 550cGy on day −1. HLA-identical (HLA-ID) siblings donated cytokine mobilized PB to 62 recipients and unrelated donor (UD) BM was used for 69 patients. GVHD prophylaxis consisted of single agent cyclosporine (CSP) for recipients of HLA-ID allografts and CSP, methotrexate, and methylprednisolone in recipients of UD BM. The median age of recipients was 45 years (range 21–70), with 55 males and 76 females. 43 pts were in CR1, 33 in CR2, and 55 had relapsed (rel) or refractory (ref) disease. 59 of 69 recipients of UD BM were serologically identical with their donors at 6/6 antigens. There were no graft failures in either group.With a median follow-up of over 18 months, the results of transplantation are presented in the Table.Results of TransplantationClinical OutcomeAllograft SourceHLA-ID PBUD BMGrade 2–4 Acute GVHD42%51%Extensive Chronic GVHD57%61%Disease free survival (DFS) at 2 yearsCR149+/−10%39+/−12%CR219%+/−12%38+/−11%Rel/Ref17+/−8%0%For pts transplanted in CR1, the results are comparable to those observed following fully ablative conditioning, particularly since many pts were transplanted due to high risk karyotype. In CR2, outcomes following RIC were superior in recipients of UD BM compared to HLA-ID PB, possibly due to a greater graft versus leukemia effect. UD BM was ineffective in pts with rel/ref AML. Of interest, the 2 year DFS in pts with rel/ref AML following receipt of HLA-ID PB was 17% overall, but was 28% in those that developed any acute GVHD versus 0% in those that did not (P<0.02). In conclusion, while the role of RIC in the treatment of pts with AML requires further clarification, our findings suggest that in pts beyond CR1, clinical evidence of donor alloreactivity appears to be critical for ensuring durable DFS.

Glucose‐induced Insulin Response is Reduced and Proinsulin Response Increased in Healthy Siblings of Type 1 Diabetic Patients

Glucose-stimulated insulin and proinsulin responses, and insulin sensitivity, were studied in 30 HLA identical, 38 HLA haplo-identical, and 25 HLA non-identical, healthy islet-cell-antibody negative siblings of Type 1 diabetic patients. The results were compared with 41 age- and sex-matched healthy subjects with no diabetes in the family. The proinsulin-corrected insulin response to an intravenous glucose infusion test was significantly lower among siblings when insulin sensitivity was taken into account (1.65 (inter-quartile range 1.20-2.64) vs 2.18 (1.65-3.28) nmol mmol-1 min, p = 0.04). Proinsulin values were consistently higher among siblings than among control subjects (peak values 50.0 vs 38.0 pmol l-1 (p = 0.004)). When proinsulin release was corrected for individual insulin sensitivity this difference remained. The results suggest disturbed islet B-cell function, unrelated to HLA identity or the presence of circulating islet cell antibodies.

The Genetics of Psoriasis

The purpose of this study was to determine whether the inheritance of psoriasis is HLA linked. We studied 12 families with at least two siblings with psoriasis. We used a sib pair analysis comparing the HLA haplotypes in affected siblings of these families. Haplotype sharing was analyzed in 15 sib pairs; expected frequencies of haplotype sharing were estimated as 25% for HLA identity and 50% for haplotype identity. All sib pairs shared at least one haplotype and 13 of the 15 were HLA identical, compared with the expected frequency of four. These results suggest that at least one, and probably more, HLA-linked genes are implicated in the development of psoriasis.

Triad of Markers for Identifying Children at High Risk of Developing Insulin-Dependent Diabetes Mellitus

A longitudinal investigation was conducted from 1977 to 1984 on 178 families in which one or more of the children had insulin-dependent diabetes mellitus. Of 351 nondiabetic sibs followed up for an average of 54 months, ten have, thus far, become diabetic. Eight sibs were HLA identical to their diabetic proband and nine had HLA-DR3 and/or HLA-DR4. Islet cell surface antibody and islet cell cytoplasmic antibody were found from two to 74 months before the onset of clinical diabetes in 100% and 90%, respectively, of the children. A decrease in insulin secretion was observed in all of these children on entry into the study and was detected in the absence of elevated plasma glucose concentrations. The data suggest that the triad of HLA identity, pancreatic islet cell antibodies, and depressed insulin secretion identifies those sibs who are at high risk of developing insulin-dependent diabetes mellitus.

The use of cyclosporine in living-related renal transplantation. Donor-specific hyporesponsiveness and steroid withdrawal.

Fourteen HLA-identical (HLA-ID) and 62 haploidentical (HP-ID) living-related donor (LRD) renal allograft recipients were transplanted using cyclosporine (CsA) and prednisone immunosuppression. No patients were preconditioned with pretransplant blood transfusions (third-party or donor-specific)--and, therefore, none were sensitized to their donor. Patient 93% (13/14) and graft 93% (13/14) survival for the HLA-ID patients is not significantly different (P greater than .1) compared with patient 98% (61/62) and graft 91% (56/62) survival in the HP-ID patients, with a mean follow-up of 16.3 (8-30) and 14.7 (2-35) months, respectively. A significant difference was noted in the incidence of treated rejection episodes (0% vs. 31%, P less than .01) and the mean serum (mg/dl) creatinine (1.37 vs. 1.71, P less than .05) at 18 months between the HLA-ID and the HP-ID and HP-ID recipients, respectively. Ten of 22 HP-ID recipients demonstrated donor-specific mixed lymphocyte culture hyporesponsiveness one year posttransplant that may have been due to the emergence of monocytoid suppressor cells. Nine of these HP-ID and seven HLA-ID recipients were subjected to a protocol of steroid withdrawal. Eleven of these patients are currently on CsA monodrug therapy and two are on alternate-day steroids from 9-18 months after discontinuation of prednisone. These findings suggest that CsA is an effective steroid-sparing agent in LRD renal transplantation that diminishes the frequency of treated rejection episodes and may permit monodrug therapy in selected individuals.

Pitfalls of prenatal diagnosis of 21-hydroxylase deficiency (21-OH def) congenital adrenal hyperplasia (CAH)

Hormonal measurements and HLA genotyping of amniotic fluid at midgestation correctly predicted the postnatal dx of CAH in 26 of 29 fetuses at risk for CAH. Of these 26, 6 were predicted to have classical 21-OH def based on elevated amniotic fluid 17-hydroxyprogesterone (17-P) and Δ4-androstenedione (A). These 6 fetuses and their index cases were ultimately proven to have salt-wasting classical 21-OH def. Of 3 HLA typed, genotype was identical to the index case. Normal amniotic fluid 17-P and A in the remaining 20 predicted fetuses unaffected with classical CAH, and these patients have been clinically asymptomatic to date or biochemically proven not to be affected with classical or nonclassical CAH. Of the 20 fetuses, 6 were HLA typed and predicted to be homozygous unaffected or heterozygous. However, in 3 of the 29 fetuses, prenatal diagnosis was incorrect. In one, the fetus was predicted to have CAH based on HLA identity to the index case, but amniotic fluid 17-P and A were normal and the fetus was normal. The index case of this family did not have CAH but was a normal child. Thus, amniotic fluid hormone levels accurately predicted a normal fetus while HLA typing was not relevant in prenatal dx because the index case was unaffected. The second fetus was predicted to be a carrier on the basis of HLA typing and normal amniotic fluid 17-P and A. However, during infancy the female infant was shown to have nonclassical CAH and be HLA identical to the index case. The index case in this family, presumed to have classical CAH, was later diagnosed to have nonclassical CAH. In the third case, the fetus was predicted to be a heterozygote by HLA genotyping and to be unaffected by hormonal measurement. Postnatally, at age 2 7/12 yrs, the male child was shown to have non-salt-losing classical CAH and to be HLA identical to the index case who also has non-salt-losinq CAH. These data demonstrate that in salt-losing classical CAH, prenatal dx of the homozygous affected fetus is reliable by the measurement of amniotic fluid 17-P and A. In nonclassical or non-salt-losing classical CAH, amniotic fluid 17-P and A are in the normal range, thus prenatal dx is not possible by hormonal evaluation. Both hormonal and HLA studies of fetal amniotic fluid, as well as correct dx of the specific form of 21-OH def and HLA studies of the index case, are essential in diagnosing the specific form of 21-OH def CAH in the fetus.

PITFALLS OF PRENATAL DIAGNOSIS OF 21-HYDROXYLASE DEFICIENCY CONGENITAL ADRENAL HYPERPLASIA (CAH)

Hormonal measurements and HLA genotyping, of amniotic fluid at midgestation correctly predicted the postnatal dx of CAH in 26 of 29 fetuses at risk for CAH. Of these 26, 6 were predicted to have classical 21-hydroxylase deficiency (21-OH def) based on elevated amniotic fluid 17-hydroxyprogesterone (17-P) and Δ4-androstenedione (A). These 6 fetuses and their index cases were ultimately proven to have salt-wasting classical 21-OH def. Of 3 HLA typed, genotype was identical to the index case. Normal amniotic fluid 17-P and A in the remaining 20 predicted fetuses unaffected with classical CAH, and these patients have been clinically asymptomatic to date or biochemically proven not to be affected with classical or nonclassical CAH. Of the 20 fetuses, 6 were HLA genotyped and predicted to be homozygous unaffected or heterozygous. However, in 3 of the 29 fetuses, prenatal diagnosis was incorrect. In one, the fetus was predicted to have CAH based on HLA identity to the index case. However, amniotic fluid 17-P and A were normal and the fetus was normal. The index case of this family did not have CAH but was a normal child. Thus, amniotic fluid hormone levels accurately predicted a normal fetus while HLA genotyping was not relevant in prenatal dx because the index case was unaffected. The second fetus was predicted to be a carrier on the basis of HLA genotyping and normal amniotic fluid 17-P and A. However, during infancy the female infant was shown to have nonclassical CAH and to be HLA identical to the index case. The index case in this family, presumed to have classical CAH, was later diagnosed to have nonclassical CAH. Thus, in nonclassical CAH, hormonal measurement of 17-P and A is not useful in prenatal dx; only correct HLA genotyping of the fetus is valuable. In the third case, the fetus was predicted to be a heterozygote by HLA genotyping and to be unaffected by hormonal measurement. Postnatally, at age 2 7/12 yrs, the male child was shown to have non-salt-losing classical CAH and was shown to be HLA identical to his brother (index case) who also has non-salt-losing CAH. CONCLUSION: These data demonstrate that in salt-losing classical CAH, prenatal dx of the homozygous affected fetus is reliable by the measurement of amniotic fluid 17-P and A. In nonclassical or non-salt-losing classical CAH, amniotic fluid 17-P and A are in the normal range, thus prenatal dx is not possible by hormonal evaluation. Both hormonal and HLA studies of fetal amniotic fluid, as well as correct dx of the specific form of 21-OH def and HLA studies of the index case, are essential in diagnosing the specific form of 21-OH def CAH in the fetus.

HLA genotypes in familial Hodgkin's disease. Excess of HLA identical affected sibs

The observations of HLA-genotyped 13 family cases of Hodgkin's disease including 7 pairs of affected sibs, 4 parent/child cases and 2 pairs of first cousins are reported. Among the pairs of affected sibs, an excess of HLA identical patients ( 6 observed out of 7) ( 1.75 expected) do not reach the level of statistical significance. However when the results are pooled with international data, the increased frequency of HLA identity among the affected sibs reaches a significant level (P < 0.05). This observation strongly supports the hypothesis of the role of the HLA complex as one of the factors of susceptibility to Hodgkin's disease.

HLA identity in juvenile onset diabetes.

Hla typing at the A and B locus was performed in 13 sibships of juvenile onset diabetics (JOD). Eight families had more than one diabetic sibling. HLA identity was significantly associated with the development of JOD. Fifty-five per cent of the HLA identical index siblings were diabetic. HLA-B8 was significantly increased in the diabetic sibs. There was a significant increase in HLA-A28 and decrease in HLA-B17 in the non-diabetic siblings compared with controls.

Human lymphocyte-dependent antibody mediated cytotoxicity and direct lymphocyte cytotoxicity against non-HL-A antigens.

EXPRESSION of the major transplantation antigens in humans is generally considered to be controlled by the genes of the HL-A region1–4. Skin, kidney and bone marrow transplants usually survive longer when donors and recipients are HL-A identical than when they are not5–7. However, the fact that grafts are still rejected with HL-A identity and negative mixed lymphocyte reactivity (MLR)8–11 strongly suggests the presence of minor transplantation antigens. The major problem to date has been the development of in vitro assay systems to detect these antigens.