Allogeneic Marrow Transplantation Research Articles

Allogeneic bone marrow transplantation for patients with treatment-refractory Crohn's Disease

Background & aimsDurable remissions of Crohn's Disease (CD) have followed myeloablative conditioning therapy and allogeneic marrow transplantation. For patients with treatment-refractory disease, we used reduced-intensity conditioning to minimize toxicity, marrow from donors with low Polygenic Risk Scores for CD as cell sources, and protracted immune suppression to lower the risk of graft-versus-host disease (GVHD). Our aim was to achieve durable CD remissions while minimizing transplant-related complications. MethodsDNA from patients and their HLA-matched unrelated donors was genotyped and Polygenic Risk Scores calculated. Donor marrow was infused following non-myeloablative conditioning. Patient symptoms and endoscopic findings were documented at intervals after transplant. ResultsWe screened 807 patients, 143 of whom met eligibility criteria; 2 patients received allografts. Patient 1 had multiple complications and died at day 332 from respiratory failure. Patient 2 had resolution of CD symptoms until day 178 when CD recurred, associated with persistent host chimerism in both peripheral blood and intestinal mucosa. Withdrawal of immune suppression was followed by dominant donor immune chimerism in peripheral blood and resolution of CD findings. Over time, mucosal T-cells became donor-dominant. At 5 years after allografting, Patient 2 remained off all medications but had mild symptoms related to a jejunal stricture that required stricturoplasty at 6 years. At 8 years, she remains stable off medications. ConclusionsThe kinetics of immunologic chimerism after allogeneic marrow transplantation for CD patients depends on the intensity of the conditioning regimen and the magnitude of immune suppression. One patient achieved durable improvement of her previously refractory CD only after establishing donor immunologic chimerism in intestinal mucosa. Her course provides proof-of-principal for allografting as a potential treatment for refractory CD, but an immunoablative conditioning regimen should be considered for future studies.(ClinicalTrials.gov, NCT01570348)

Non-myeloablative allogeneic blood or marrow transplantation (AlloBMT) with post-transplant cyclophosphamide (PTCy) for peripheral T-cell lymphoma (PTCL): Improved outcomes with peripheral blood (PB) allografts and increased total body irradiation (TBI) to 400 cGV.

7047 Background: The use of PTCy for graft-versus host-disease (GVHD) prophylaxis has revolutionized alloBMT, but there is limited published experience in PTCL. Methods: All patients with PTCL who received a non-myeloablative alloBMT using PTCy-based GVHD prophylaxis between January 2004 and December 2020 at Johns Hopkins Hospital were analyzed. Standard population statistics were used. Results: Sixty-five patients were identified. The median age was 59 years (range, 24-75 years). Lymphoma histology included PTCL-not otherwise specified (n=24), ALK-negative anaplastic large cell lymphoma (n=14), angioimmunoblastic T-cell lymphoma (n=7), enteropathy-associated T-cell lymphoma (n=6), hepatosplenic T-cell lymphoma (n=4), and other (n=10). Eleven patients were in first complete remission (CR1, 17%). The remaining patients were in first partial remission (PR1) or underwent salvage therapy to at least PR prior to transplant. Forty-eight patients received an alloBMT from a haploidentical related donor (74%), 10 from a fully matched donor (15%), and 7 from a mismatched unrelated donor (mMUD, 11%). All patients received non-myeloablative conditioning with fludarabine, cyclophosphamide, and TBI. The graft source was bone marrow (BM) in the first 46 patients (71%). Because of relatively high relapse rates, in 2018 we began using PB and increased TBI from 200 to 400 cGy; the remaining 19 patients (29%) received this regimen. GVHD prophylaxis was PTCy, mycophenolate mofetil, and a calcineurin inhibitor or sirolimus. With a median follow up of 2.8 years, the 3-year progression-free survival (PFS) for the entire cohort was 39% (95% confidence interval [CI] 28-54%), and the 3-year overall survival (OS) was 43% (95% CI 31-58%). The cumulative incidence (CuI) of relapse and non-relapse mortality (NRM) at 1 year was 25% (95% CI 14-35%) and 12% (95% CI 4-20%), respectively. Among 29 cases of GVHD (45%), 2 were grade 3-4 acute GVHD (3%) and 3 were severe chronic GVHD (5%). Univariate analysis including age, histology, mMUD, PB/400cGy, and CR1 revealed only PB/400 cGy TBI as a significant predictor of survival, relapse, or NRM. Outcomes by source. Conclusions: AlloBMT with non-myeloablative conditioning and PTCy is safe and well-tolerated in patients with PTCL. Our preliminary data suggest increasing TBI dose to 400 cGy and using PB allografts may offer improved disease control and better survival outcomes, though additional studies are needed to confirm these findings. [Table: see text]

ABCL-006: High Grade Primary Bone Lymphoma with TdT Expression

Context Distinguishing mature B-cell lymphomas from immature or precursor B-cell neoplasms is important since different treatments are usually given. It is known that some mature B-cell neoplasms can have relatively immature morphologic features and present similarly to a leukemia. Expression of TdT in lymphomas that are typically negative for TdT can occur rarely and present a diagnostic challenge. This entity can present de novo or in the setting of a relapsed/refractory lymphoma, usually follicular lymphomas. Primary bone lymphoma, characterized by exclusive bone or marrow involvement, represents less than 2% of all lymphomas in adults. Its frequency is lower in children and young adults. Objective To describe a case of a high-grade primary bone lymphoma with TdT expression. Setting A 35 yo man was admitted for severe bone pain, fever, and night sweats. Laboratory showed no abnormalities; HIV, HCV, and HBV serologies and blood cultures including atypical germs were negative. Magnetic resonance showed disseminated bone lesions predominant in column and pelvis. Bone marrow biopsy showed an infiltration by a CD20, CD 10 BCL2 positive high grade B cell lymphoma. MUM1 and TdT were negative. He initiated treatment with R-DA-EPOCH presenting refractory disease after 3 cycles: PET/CT uptake in both clavicles, humerus, scapula, dorsolumbar raquis, iliac bones and ribs. Max SUV was 20 in the 7th right rib. A new biopsy was done which result was consistent with an infiltration by a B cell neoplasm with 2 different populations: both positive for CD10, PAX5, BCL2 and one positive for TdT and CD20 while the other was CD20 and TdT negative. High-grade lymphoma and areas of a B cell lymphoblastic like neoplasm expressing TdT was the final diagnosis. His treatment was changed to R Hyper-CVAD plus triple intrathecal chemotherapy, and he is currently undergoing that treatment. Consolidation with allogeneic marrow transplant is planned. Summary/Conclusion TdT positive neoplasms diagnostic is challenging. Whether this case represents a composite neoplasm (high grade lymphoma with lymphoblastic leukemia/lymphoma) or if it is a transformation from a previous asymptomatic lymphoma is a matter of debate. Distinguishing mature B-cell lymphomas from immature or precursor B-cell neoplasms is important since different treatments are usually given. It is known that some mature B-cell neoplasms can have relatively immature morphologic features and present similarly to a leukemia. Expression of TdT in lymphomas that are typically negative for TdT can occur rarely and present a diagnostic challenge. This entity can present de novo or in the setting of a relapsed/refractory lymphoma, usually follicular lymphomas. Primary bone lymphoma, characterized by exclusive bone or marrow involvement, represents less than 2% of all lymphomas in adults. Its frequency is lower in children and young adults. To describe a case of a high-grade primary bone lymphoma with TdT expression. A 35 yo man was admitted for severe bone pain, fever, and night sweats. Laboratory showed no abnormalities; HIV, HCV, and HBV serologies and blood cultures including atypical germs were negative. Magnetic resonance showed disseminated bone lesions predominant in column and pelvis. Bone marrow biopsy showed an infiltration by a CD20, CD 10 BCL2 positive high grade B cell lymphoma. MUM1 and TdT were negative. He initiated treatment with R-DA-EPOCH presenting refractory disease after 3 cycles: PET/CT uptake in both clavicles, humerus, scapula, dorsolumbar raquis, iliac bones and ribs. Max SUV was 20 in the 7th right rib. A new biopsy was done which result was consistent with an infiltration by a B cell neoplasm with 2 different populations: both positive for CD10, PAX5, BCL2 and one positive for TdT and CD20 while the other was CD20 and TdT negative. High-grade lymphoma and areas of a B cell lymphoblastic like neoplasm expressing TdT was the final diagnosis. His treatment was changed to R Hyper-CVAD plus triple intrathecal chemotherapy, and he is currently undergoing that treatment. Consolidation with allogeneic marrow transplant is planned. TdT positive neoplasms diagnostic is challenging. Whether this case represents a composite neoplasm (high grade lymphoma with lymphoblastic leukemia/lymphoma) or if it is a transformation from a previous asymptomatic lymphoma is a matter of debate.

Influence of hepatic Graft-Versus-Host-Disease (GVHD) on the pharmacokinetics of ciclosporin in a case of acute myeloid leukemia treated at the EHU Oran

Acute myeloid leukemia (AML) is a malignant blood disease that affects hematopoietic cells in the bone marrow. The best treatment for AML is allogeneic hematopoietic stem cell transplantation (HSC). To prevent and treat the main complication of allogeneic marrow transplant, graft versus host disease (GVHD), it is necessary to combine immunosuppressive therapy which includes ciclosporin (CsA). The objective of our work is to study the influence of hepatic GVHD on the pharmacokinetics of cyclosporin in an AMLcase. This is an allografted patient (CSH), presented to our Pharmacovigilance department at the EHU of Oran in Algeria, with the aim of carrying out therapeutic pharmacological monitoring (TPM) of ciclosporin. We proceeded to assay for residual ciclosporinaemia from D1 of the allogeneic transplant. The patient presented a fluctuation of the trough concentrations, the explanation of which was an onset of acute hepatic GVHD, confirmed by biopsy with an elevated hepatic function, which represents an incidence varying between 10 and 50% in patients receiving transplant from a genoidentical donor. Without forgetting the great inter-individual and intra-individual variability of the response to ciclosporin, the environmental and pathological factors and the numerous drug interactions which can be the cause of modification of the pharmacokinetics and the pharmacodynamics of this drug. In conclusion, the pharmacological monitoring of cyclosporin, which is the treatment of choice to prevent or treat GVHD, is mandatory due to its low therapeutic index and high inter- and intra-individual variability.

A phase II study of azacitidine in combination with granulocyte-macrophage colony-stimulating factor as maintenance treatment, after allogeneic blood or marrow transplantation in patients with poor-risk acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS)

Relapse is the most common cause of treatment failure following allogeneic blood or marrow transplantation (alloBMT) for AML or MDS. Post-transplant maintenance therapies may prevent relapse. We conducted a phase II trial combining azacitidine (AZA) with GM-CSF in non-relapsed, post-transplant patients with AML or MDS. Patients received escalating doses of AZA to a maximum of 75 mg/m2 for 5 days per cycle for up to 12 cycles. GM-CSF was given on days 1–10 of each cycle. Eighteen patients were treated following non-myeloablative (17) and myeloablative (1) alloBMT for AML (61.1%), MDS (27.7%), or therapy-related myeloid neoplasm (11.1%). The majority of patients (72%) received their graft from an HLA-haploidentical donor. The treatment was well-tolerated with rare grade 3–4 hematologic toxicities. One patient suffered an exacerbation of GVHD. The 24-month relapse-free and overall survivals were 47 and 57%, respectively, with a median of 18.6 and 29 months.

Editorial Note on Cancer

Bone marrow or fringe blood undeveloped cell transplantation is utilized in the therapy of malignancy for two reasons. In the first place, transplantation licenses abuse of the lofty dose?response relationship found in certain tumors by permitting organization of dosages of foundational chemotherapy and radiotherapy that without transplantation would cause unsatisfactorily extreme or deadly myelosuppression. Second, transplantation of allogeneic marrow presents an antitumor impact, separate from the impacts of chemoradiotherapy. The first fruitful bone marrow transfers in quite a while were acted in the last part of the 1960s.

Autologous bone marrow transplantation for acute myeloid leukemia using monoclonal antibody-purged bone marrow

We report our experience from a clinical trial of autologous bone marrow transplantation (ABMT) in the treatment of 30 patients with acute myeloid leukemia (AML) using monoclonal antibody (MoAb) and complement-treated bone marrow. All patients were in complete remission (CR) at the time of transplant: 6 patients were in first CR, 18 in second CR, and 6 in third CR. The median age of all patients was 42 years (range 11 to 57 years). For marrow ablation, 28 patients were treated with cyclophosphamide and total body irradiation. One patient was treated with busulfan and cyclophosphamide and one was treated with busulfan and VP-16. Each patient was then transfused with autologous bone marrow that had been harvested previously and treated with two MoAbs, PM-81 and AML-2-23, and rabbit complement. Median time to recovery of neutrophils (500/microL) was 30 days, and platelets (20,000/microL) was 45 days. Median time for initial erythrocyte engraftment, assessed by a flow cytometric reticulocyte assay, was 13 days. Median overall and relapse-free survival of first CR patients was at least 17.4 months post-ABMT and the 2- and 3-year actuarial overall and relapse-free survival was 67% (+/- 19%). Median survival for the 24 patients in second or third CR was 6.8 months post-ABMT and 9.3 months since CR; however, six patients survived disease-free from 16 to 61 months post-ABMT. For the second and third CR group it was observed that six patients (5 of the 6 survivors) showed "inversions," when their post-ABMT remission lasted longer than any previous one. Actuarial 2- and 3-year disease-free and overall survival of patients in second and third CR was 25% (+/- 9%) and 18% (+/- 9%), and 29% (+/- 9%) and 23% (+/- 9%), respectively. ABMT avoids the problems of graft-versus-host disease and of finding suitable donors for allogeneic marrow transplantation.

TAK1 inhibition ameliorates survival from graft-versus-host disease in an allogeneic murine marrow transplantation model.

Acute graft-versus-host disease(GVHD) isa major cause of morbidity and mortality in allogeneic hematopoietic cell transplantation (allo-HCT). Majority of the current immunosuppressive strategies targeting donor T cells to prevent or treat acute GVHD are only partially effective, and often require escalated immunosuppressive therapy. Recent studies have revealed that activation of antigen-presenting cells in the proinflammatory milieu is important for the priming and promotion of GVHD. This activation is mediated by innate immune signaling pathways, which therefore potentially represent new targets in addressing GVHD. Using gene expression analysis of peripheral monocytes from patients' post-allo-HCT, we detected an upregulation of TGF-β-activated kinase 1 (TAK1), a key regulator of the toll-like receptor signaling pathway. 5Z-7-oxozeaenol, a selective inhibitor of TAK1, reduced proinflammatory cytokine production by activated monocytes under lipopolysaccharide stimulation and T cell proliferation in allogeneic-mixed leukocyte reactions with monocyte-derived dendritic cells. In an experimental mouse model of GVHD, 5Z-7-oxozeaenol administration after allo-HCT ameliorated GVHD severity and mortality, with significant reduction in serum TNFα, IL-1β, and IL-12 levels. Our findings suggest that altering the activation status of innate immune cells by TAK1 inhibition may be a novel therapeutic approach for acute GVHD.

Comparable composite endpoints after HLA-matched and HLA-haploidentical transplantation with post-transplantation cyclophosphamide.

Composite endpoints that not only encompass mortality and relapse, but other critical post-transplant events such as graft-versus-host disease, are being increasingly utilized to quantify survival without significant morbidity after allogeneic blood or marrow transplantation. High-dose, post-transplantation cyclophosphamide reduces severe graft-versus-host disease with allogeneic marrow transplantation, making composite endpoints after this management particularly interesting. We retrospectively analyzed 684 adults with hematologic malignancies who received T-cell-replete bone marrow grafts and cyclophosphamide after myeloablative HLA-matched related (n=192) or unrelated (n=120), or non-myeloablative HLA-haploidentical (n=372) donor transplantation. The median follow up was 4 (range, 0.02-11.4) years. Graft-versus-host disease-free, relapse-free survival was defined as the time after transplantation without grade III-IV acute graft-versus-host disease, chronic graft-versus-host disease requiring systemic treatment, relapse, or death. Chronic graft-versus-host disease-free, relapse-free survival was defined as the time after transplantation without moderate or severe chronic graft-versus-host disease, relapse, or death. One-year graft-versus-host disease-free, relapse-free survival and chronic graft-versus-host disease-free, relapse-free survival estimates were, respectively, 47% (95% CI: 41-55%) and 53% (95% CI: 46-61%) after myeloablative HLA-matched related, 42% (95% CI: 34-52%) and 52% (95% CI: 44-62%) after myeloablative HLA-matched unrelated, and 45% (95% CI: 40-50%) and 50% (95% CI: 45-55%) after non-myeloablative HLA-haploidentical donor transplantation. In multivariable models, there were no differences in graft-versus-host disease-free, or chronic graft-versus-host disease-free, relapse-free survival after either myeloablative HLA-matched unrelated or non-myeloablative HLA-haploidentical, compared with myeloablative HLA-matched related donor transplantation. Although limited by inclusion of dissimilar cohorts, we found that post-transplantation cyclophosphamide-based platforms yield comparable composite endpoints across conditioning intensity, donor type, and HLA match.

Nutritional issues and body weight in long-term survivors of allogeneic blood and marrow transplant (BMT) in NSW Australia.

The aims of this study were to describe the long-term nutrition, body weight and body image issues facing survivors of Allogeneic Blood and Marrow Transplant (BMT) and their impact on quality of life. It also describes survivors' perception of enteral feeding during BMT. Four hundred and forty-one survivors who had undergone a BMT in NSW, Australia between 2000 and 2012 (n=441/583) completed the Sydney Post BMT Study Survey (SPBS). Forty-five percent of survivors less than 2-year post-transplant reported a dry mouth, 36% reported mouth ulcers and 19% had diarrhoea. This was consistent across all survivor groups, regardless of time since transplant. Patients with one or more gastrointestinal (GI) symptoms had significantly lower quality of life scores. There was a significant difference in quality of life scores when comparing those with no GI symptoms to those with one or more symptoms (P=<0.0001). Quality of life was significantly higher in those who once again enjoyed mealtimes (P<0.0001). Males were more likely to be satisfied with their body weight compared to females (P=0.009). The median body mass index (BMI) for all patients reporting body weight satisfaction was significantly lower (BMI 23.5) than those reporting dissatisfaction (BMI 27.5) (P=<0.0001). Survivors who had a normal BMI had significantly higher rates of body weight satisfaction compared to underweight, overweight and obese survivors (P=<0.0001). Those survivors who were overweight or obese were significantly more likely to be diabetic (P=0.008). This study revealed an important relationship between gastrointestinal symptoms, body weight and body image and survivor's quality of life. It provides further support for the importance of nutrition therapy post-BMT.

Donor-Recipient Matching for KIR Genotypes Reduces Chronic GVHD and Missing Inhibitory KIR Ligands Protect against Relapse after Myeloablative, HLA Matched Hematopoietic Cell Transplantation

BackgroundAllogeneic hematopoietic cell transplantation (HCT) can be curative for many hematologic diseases. However, complications such as graft-versus-host disease (GVHD) and relapse of primary malignancy remain significant and are the leading causes of morbidity and mortality. Effects of killer Ig-like receptors (KIR)-influenced NK cells on HCT outcomes have been extensively pursued over the last decade. However, the relevance of the reported algorithms on HLA matched myeloablative HCT with rabbit antithymocyte globulin (ATG) is used for GVHD prophylaxis remains elusive. Here we examined the role of KIR and KIR-ligands of donor-recipient pairs in modifying the outcomes of ATG conditioned HLA matched sibling and unrelated donor HCTMethods and FindingsThe study cohort consisted of 281 HLA matched sibling and unrelated donor-recipient pairs of first allogeneic marrow or blood stem cell transplantation allocated into ‘discovery’ (135 pairs) and ‘validation’ (146 pairs) cohorts. High resolution HLA typing was obtained from the medical charts and KIR gene repertoires were obtained by a Luminex® based SSO method. All surviving patients were followed-up for a minimum of two years. KIR and HLA class I distributions of HCT pairs were stratified as per applicable definitions and were tested for their association with cause specific outcomes [acute GVHD grade II-IV (aGVHD), chronic GVHD needing systemic therapy (cGVHD) and relapse] using a multivariate competing risks regression model as well as with survival outcomes [relapse-free survival (RFS), cGVHD & relapse free survival (cGRFS) and overall survival (OS)] by multivariate Cox proportional hazards regression model. A significant association between KIR genotype mismatching (KIR-B/x donor into KIR-AA recipient or vice versa) and cGVHD was found in both discovery (p = 0.001; SHR = 2.78; 95%CI: 1.50–5.17) and validation cohorts (p = 0.005; SHR = 2.61; 95%CI: 1.33–5.11). High incidence of cGVHD associated with KIR genotype mismatching was applicable to both sibling and unrelated donors and was specific to recipients who had one or two C1 bearing HLA-C epitopes (HLA-C1/x, p = 0.001; SHR = 2.40; 95%CI: 1.42–4.06). When compared with KIR genotype mismatched transplants, HLA-C1/x patients receiving grafts from KIR genotype matched donors had a significantly improved cGRFS (p = 0.013; HR = 1.62; 95%CI: 1.11–2.39). Although there was no effect of KIR genotype matching on survival outcomes, a significantly reduced incidence of relapse (p = 0.001; SHR = 0.22; 95%CI: 0.10–0.54) and improved relapse-free survival (p = 0.038; HR = 0.40; 95%CI: 0.17–0.95) was observed with one or more missing ligands for donor inhibitory KIR among the recipients of unrelated donor transplants.ConclusionsThe present study for the first time presents the beneficial effects of KIR genotype matching in reducing cGVHD in myeloablative transplant setting using HLA matched (sibling and unrelated) donors. The findings offer a clinically applicable donor selection strategy that can help control cGVHD without affecting the risk of relapse and/or identify patients at a high risk of developing cGVHD as potential candidates for preemptive therapy. The findings also affirm the beneficial effect of one or more missing inhibitory KIR ligands in the recipient in reducing relapse and improving a relapse free survival in unrelated donor transplants.

Mixed chimerism renders residual host dendritic cells incapable of alloimmunization of the marrow donor in the canine model of allogeneic marrow transplantation.

This study tested whether an alloimmune response can occur in the marrow donor when infused or injected with leukocytes from their mixed chimeric transplant recipient. Two mixed chimeras were produced after conditioning with three Gray total body irradiation, donor marrow infusion, and post-grafting immunosuppression. The marrow donors were then repeatedly infused and injected with leukocytes from their respective chimeric recipient. A donor lymphocyte infusion (DLI) into their mixed chimeras had no effect, even after the experiments were repeated. The presence of blood dendritic cells (DCs) of recipient origin was confirmed in chimeric recipients, as well as the presence of microchimerism in the marrow donors. Donor sensitization did occur following placement of a recipient skin graft that was confirmed following DLI into recipients that changed the mixed chimeras into full donor chimeras. These observations suggest that mixed chimerism renders recipient peripheral blood DCs incapable of inducing a donor T cell response.

Prognostic Value of Minimal Residual Disease Assessed By WT1 Expression Level and Flow Cytometry in Acute Myeloid Leukemia Patients Undergoing Allogeneic Marrow Transplantation

Background: Allogeneic bone marrow transplantation (BMT) offers the greatest chance of cure for most patients affected by acute myeloid leukemia (AML). Persistence of disease or high levels of pre BMT minimal residual disease (MRD) have been reported to predict disease relapse after BMT. WT1 expression levels and multicolor flow cytometry (MFC) are widely used as markers of MRD. We recently reported that combined evaluation of MRD by WT1 and MFC after induction therapy can predict relapse risk in AML patients.Aims: The aim of the present study was to apply the same MRD assessment in pre BMT setting to evaluate its reliability in predicting relapse.Methods: We retrospectively analyzed BMT outcome of 66 AML patients with both WT1-based and MFC-based MRD evaluation on bone marrow samples before transplant. Median age at transplant was 44 years. Forty-one were transplanted in first and twenty-five in second or subsequent complete remission. Induction therapies included fludarabine-containing regimens or standard ara-C and daunorubicin schedule (3+7). Median follow-up was 44 months (range 0-119 months); pre-transplantation evaluations were performed at a median of one month before transplant (range 1-3). Disease-free survival (DFS) was calculated from the time of transplantation until last follow-up or documented leukemic relapse. Overall survival was calculated from the time of transplantation to the last follow-up or death for any cause. All causes of death not directly due to relapse or progression of leukemia were considered as non-relapse mortality. A positive MFC MRD was defined by the presence of no less than 25 clustered leukemic cells /105 total events (threshold of 2.5x10-4 residual leukemic cells) at four-color flow-cytometry. Real-time PCR for WT1 was performed on DNA Engine 2 (Opticon®, MJResearch®). WT1 copy number/Abl copy number 500x104 was used as cut-off value for high WT1 expression.Results: Twenty-five relapses (37.9%) were observed. Median DFS was 31 months. Our analysis shows that the probability of relapse was significantly influenced only by disease status (first or subsequent CR) and MRD status at transplantation. Specifically, MFC-MRD was the strongest predictor of longer disease free survival (p <0.001) since no relapses occurred in the eleven MFC-MRD negative patients. Among MFC-MRD positive patients a further stratification of relapse risk is obtained by the evaluation of WT1. Patients with double positive MRD had a significantly worse DFS compared with patients who were MRD positive by MFC but MRD negative by WT1 (p <0.01). The predictive value of MRD was independent from different induction schedules; furthermore the favorable prognostic value of achieving a negative MRD status was not affected by undergoing BMT in second or subsequent remission. Median OS was 26 months and was significantly influenced by disease status and MRD status at transplantation and by relapse after BMT. Cumulative non relapse mortality was 23% at 36 months and was not associated with pre-BMT status.Conclusion: pre BMT MRD evaluation by WT1 and MFC on bone marrow samples is a reliable tool to predict relapse risk. Patients with negative pre-BMT MRD have a significantly longer DFS and OS, while MRD positive patients by both methods display a higher risk of relapse. Patients at higher risk of poor outcome should undergo a more stringent program of post BMT evaluations, in order to detect disease relapse earlier and might be candidate for pre-emptive therapeutic interventions aimed at delaying or avoiding AML reoccurrence. DisclosuresNo relevant conflicts of interest to declare.

Oral squamous cell carcinoma positive for p16/human papilloma virus in post allogeneic stem cell transplantation: 2 cases and review of the literature

Complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT) includes the risk of secondary malignancies. This may be related to mechanisms including radiation and chemotherapy regimens, chronic graft-versus-host disease, inflammation, and prolonged imunosuppression. Oral squamous cell carcinoma (OSCC) is a complication associated with chronic graft-versus-host disease after allo-HSCT. Although human papillomavirus (HPV) is known to be associated with OSCC, the role of HPV in development of OSCC in post-HSCT patients has not been studied. We identified 2 cases of OSCC in allo-HSCT recipients. Both biopsy specimens tested positive for p16(INK4A), a surrogate marker for HPV. We propose that the association of OSCC and HPV in patients after allo-HSCT may not be incidental. Clinical implications of these cases may imply the need for a HPV screening, early intervention, and consideration of anti-HPV vaccination in this population. The effectiveness of such interventions could be validated in a prospective clinical study.

Regenerative medicine: the hurdles and hopes

Regenerative medicine is characterized as the process of replenishing or restoring human cells, tissues, or organs to restore or reestablish normal function. This field holds the promise of transforming human medicine, by actually curing or treating diseases once poorly managed with conventional drugs and medical procedures.

Partially Mismatched Transplantation and Human Leukocyte Antigen Donor-Specific Antibodies

The presence of donor human leukocyte antigen (HLA)-specific antibodies (DSA) increases engraftment failure risk in partially HLA-mismatched, or HLA-haploidentical, allogeneic marrow (alloBMT) transplantation. As pre-existing sensitization to HLA antigens is not well characterized among candidates for HLA-haploidentical alloBMT, we retrospectively evaluated both the incidence and relative strength of DSA in this patient population. Based on correlations of solid-phase antibody assays on the Luminex (Luminex, Austin, TX) platform with actual crossmatch tests, DSA were characterized as weak for results that were consistent with negative flow cytometric crossmatch results or as moderate-to-strong for results consistent with positive flow cytometric or cytotoxicity crossmatches. We evaluated 296 alloBMT candidates; 111 (37.5%) were female. DSA were detected in 43 (14.5%) candidates, mostly among female candidates (42.9% female versus 12.5% male). Moderate-to-strong DSA strength was more frequently encountered when directed against haploidentical donors as compared with mismatched unrelated donors. DSA were most commonly detected in female patients directed against their children. Because the presence of DSA has been considered prohibitive for HLA-mismatched alloBMT, we additionally report a desensitization methodology used to reduce DSA to negative or weak levels, ie, levels well below those detectable in a flow cytometric crossmatch. Nine patients without other available donors underwent desensitization. Eight who reduced their DSA to negative or weak levels proceeded to alloBMT and achieved full donor engraftment. These data support routine DSA evaluation in all patients considered for mismatched alloBMT; however, for patients with no other viable options, desensitization to weak or negative DSA levels may afford the opportunity for successful transplantation.

Elastase inhibition is not a requirement for the anti-inflammatory effects of Alpha-1 Antitrypsin: studies in neutrophil models

As an acute phase protein, alpha-antitrypsin (AAT) is thought to play an important role in limiting host tissue injury by proteases released from activated myeloid cells, specifically neutrophil elastase (NE). The clinical importance of AAT is highlighted in individuals with inherited deficiency in circulating AAT who have an increased susceptibility to early onset pulmonary emphysema, chronic bronchitis, bronchiectasis, and liver diseases. Administration of exogenous human plasma-derived AAT is used in various animal models to test the value of AAT augmentation therapy. Unrelated to emphysema models, administration of exogenous AAT inhibits HIV 1 expression, prevents murine islet cell allografts from rejection, blocks cell apoptosis and increases survival in an allogeneic marrow transplantation models. The mechanism of the above mentioned anti-inflammatory activities of AAT has been assumed to be due to its anti-proteolytic activity; however this has not been studied. We hypothesized that the anti-elastase activity of AAT was not required for its anti-inflammatory properties. To investigate this prediction, effects of native human plasma derived (nAAT, inhibitory form) and recombinant (rAAT, non-inhibitory form) on lipopolysaccharide (LPS)-induced IL-8 and TNFα release from neutrophils isolated from human blood or the bone marrow from wild type (WT) and elastase deficient mice (NE-/-) were examined. When WT or NE deficient neutrophils were treated with LPS plus rAAT (50 nM), release of TNFα (42%, p=0.002 and 24%, p=0.011, respectively) as well as of IL-8 was decreased (57%, p=0.004 and 40%, p=0.01, respectively) relative to LPS challenged cells. By comparison, to achieve the same reduction in TNFα from either WT or NE deficient neutrophils, a concentration of nAAT of 2000 nM was required. Next, human blood neutrophils were incubated with LPS (10ng/ml) alone or LPS plus increasing concentrations of nAAT or rAAT. After 8 and 18 hours, cytokines were measured in the supernatants. At 20.000 nM, nAAT reduced TNFα release by 46% (p=0.002) and IL-8 by 29%, (p=0.024). However, markedly lower concentrations of rAAT (5nM) reduced TNFα release by 41% (p=0.004) and IL-8 by 40% (p=0.05). We conclude that anti-proteolytic activity of AAT may be required but less important for its anti-inflammatory function. Acknowledgments: This study was supported by Soohyun Kim who provided the rAAT and our collaborator Charles A. Dinarello.

Success of allogeneic marrow transplantation for children with severe aplastic anaemia

Allogeneic marrow transplantation offers curative therapy for children with severe aplastic anaemia (SAA). We report the outcomes of 148 children with SAA who received human leucocyte antigen (HLA)-matched related marrow grafts between 1971 and 2010. Patients were divided into three groups, reflecting changes in conditioning and graft-versus-host disease (GVHD) prophylaxis regimens that occurred over time. Patients in Group 1 were conditioned with cyclophosphamide (CY; 200 mg/kg) followed by 'long' (102 d) methotrexate (MTX). Patients in Groups 2 and 3 received CY alone (Group 2) or combined with anti-thymocyte globulin (Group 3) followed by 'short' (days 1, 3, 6, and 11) MTX and ciclosporin (until day 180). With a median follow-up of 25 years, the 5-year survivals were 66%, 95%, and 100% for Groups 1, 2, and 3, respectively (overall P < 0·0001). The 3-year estimates of graft rejection were 22%, 32%, and 7%, respectively. The probabilities of grades III-IV acute and 2-year chronic GVHD were 15%, 0%, and 3%, and 21%, 21%, and 10%, respectively. Advances in preparative and GVHD prophylaxis regimens, and supportive care during the past 40 years have led to improved outcomes for children with SAA. These results confirm the use of allogeneic marrow transplantation for children with SAA who have HLA-matched related donors.

Comparison of quantitative HCMV DNAemia in whole blood and leukocytes, and Real-Time PCR in a BMT patient

Background. HCMV is the most opportunistic viral agent in the transplantation of bone marrow and solid organ. Early therapy based on the detection of HCMV pp65 antigen in peripheral blood leukocytes, has led to a significant reduction in the incidence of related HCMV diseases.The pp65 antigenemia is difficult to standardize, while the quantification of HCMV DNA by Real-Time PCR is an alternative diagnostic approach with greater sensitivity and reproducibility, providing important information in the management of infected patients. Objectives. The aim of this study was the comparative analysis of quantitative HCMV DNAemia in leukocytes and in whole blood, with Real-time PCR, in a BMT patient with HCMV post-transplant reactivation, in order to analyze the relationship between levels of viral DNA at different time-points obtained in the two biological matrices. Study Design. The presence of HCMV DNA was detected in whole blood and peripheral blood leukocytes in a patient who underwent allogeneic marrow transplant for Ph1 + acute lymphoblastic leukemia in molecular remission. After 5-6 months, the patient has increased molecular Bcr-Abl (Philadelphia chromosome). It was activated immune reaction by means of tapering (lowering the dose of cyclosporine) that uses the GvL effect to turn negative the Philadelphia chromosome positivity (Bcr/Abl negativity). Later, the patient develops GvHD and cortisone is administered. The persistence of grafts treated with immunosuppressants periodically reactivates HCMV infection. The DNA extraction from whole-blood was performed by automatic extractor QIACUBE (Qiagen), while extraction from leucocytes was performed on a standard number of leukocytes (EXTRAcell- Nanogen).The extracted DNA was amplified by Real-Time Alert Q-PCR (Nanogen).The samples were analyzed weekly for about 5 months from 1 year after transplantation. Results. The patient at 1 year after transplantation, has three HCMV reactivation at 56th, 62th and 67th week. In all reactivations a good overlap values of viraemia in both whole blood leukocytes is shown. Conclusions. Our data confirm that the whole blood is a biological matrix with diagnostic similar performance not only to pp65 antigenaemia, as supported by extensive scientific literature, but also to the DNAemia in leukocytes that has been for a long time considered the elective matrix for evaluating the post-transplant HCMV infection, for pre-emptive therapy particularly in BMT patients.

EFFICACY OF THE COMBINED APPLICATION OF HEMOPOIETIC GROWTH FACTORS AFTER STEM HEMOPOIETIC CELL TRANSPLATATION

The restoration of hemopeisis indices after high dose chemotherapy with autologic and allogenic transplantation of stem hemopoeitic cells with the combined use of hemopoietic growth factors - erythropoietin and granulocytic colony-stimulating factor at the early post-trasplantation period has been studied. 268 patients were included into the investigation. The shortening of restoration terms of hemoglobin, leucocytes and neutrophils in the group of patients, undergoing the combined therapy of hemopoietic growth factors after autologic transplantation of stem hemopoeitic cells. The shortening of restoration terms of hemoglobin, leucocytes and neutrophils in the group of patients, undergoing the combined therapy of hemopoietic growth factors after allogenic marrow transplantation. In whole, the application of erythropoietin in the combination of with granulocyte colony-stimulating factor led to the decreased hematologic toxicity.