Common gene variants within 3'-untranslated regions as modulators of multiple myeloma risk and survival.

We evaluated the association between germline genetic variants located within the 3'-untranlsated region (polymorphic 3'UTR, ie, p3UTR) of candidate genes involved in multiple myeloma (MM). We performed a case-control study within the International Multiple Myeloma rESEarch (IMMEnSE) consortium, consisting of 3056 MM patients and 1960 controls recruited from eight countries. We selected p3UTR of six genes known to act in different pathways relevant in MM pathogenesis, namely KRAS (rs12587 and rs7973623), VEGFA (rs10434), SPP1 (rs1126772), IRF4 (rs12211228) and IL10 (rs3024496). We found that IL10-rs3024496 was associated with increased risk of developing MM and with a worse overall survival of MM patients. The variant allele was assayed in a vector expressing eGFP chimerized with the IL10 3'-UTR and it was found functionally active following transfection in human myeloma cells. In this experiment, the A-allele caused a lower expression of the reporter gene and this was also in agreement with the in vivo expression of mRNA measured in whole blood as reported in the GTEx portal. Overall, these data are suggestive of an effect of the IL10-rs3024496 SNP on the regulation of IL10 mRNA expression and it could have clinical implications for better characterization of MM patients in terms of prognosis.

Stem cell mobilization in multiple myeloma patients relapsing after previous autologous hematopoietic stem cell transplantation: A multicenter report by the Polish Myeloma Study Group.

BACKGROUND: Salvage autologous hematopoietic stem cell transplantation (autoHSCT) may be used to treat relapse of multiple myeloma occurring after previous autoHSCT. When insufficient number of hematopoietic stem cells was stored from the initial harvest, remobilization of stem cells is necessary. PURPOSE: The analysis of stem cell remobilization after previous autoHSCT. PATIENTS AND METHODS: Fifty-eight patients, 60% males, median 59 years, were included. Median time interval between autoHSCT and remobilization was 42 months. The first remobilization was performed mostly after chemotherapy: cyclophosphamide (33%), cytarabine (43%), and etoposide (19%). RESULTS: The first remobilization was successful in 67% patients. About 19% patients required plerixafor rescue, among whom it allowed for successful harvesting in 14%. Use of cyclophosphamide, cytarabine, and etoposide allowed for successful remobilization in 53%, 84%, and 55% patients, respectively. Patients treated with cytarabine had the highest yield of CD34+ cells (median 7.5 × 106 /kg vs 5.8 and 2.4 for etoposide and cyclophosphamide, P = .001). Higher percentage of patients was able to collect ≥2 × 106 CD34+ cells/kg during one leukapheresis after cytarabine (76% vs 21% for cyclophosphamide vs 36% for etoposide, P = .001). Cytarabine use was associated with lower risk of remobilization failure OR = 0.217, P = .02. Toxicity comprised mostly hematological toxicity (thrombocytopenia and neutropenia). One patient succumbed to septic shock. CONCLUSION: Remobilization after previous autoHSCT is feasible only in a proportion of patients. Cytarabine is associated with the highest rate of successful mobilization and the highest yield of mobilized CD34+ cells. The toxicity requires careful surveillance of these patients.

Identification of miRSNPs associated with the risk of multiple myeloma.

Multiple myeloma (MM) is a malignancy of plasma cells usually infiltrating the bone marrow, associated with the production of a monoclonal immunoglobulin (M protein) which can be detected in the blood and/or urine. Multiple lines of evidence suggest that genetic factors are involved in MM pathogenesis, and several studies have identified single nucleotide polymorphisms (SNPs) associated with the susceptibility to the disease. SNPs within miRNA-binding sites in target genes (miRSNPs) may alter the strength of miRNA-mRNA interactions, thus deregulating protein expression. MiRSNPs are known to be associated with risk of various types of cancer, but they have never been investigated in MM. We performed an in silico genome-wide search for miRSNPs predicted to alter binding of miRNAs to their target sequences. We selected 12 miRSNPs and tested their association with MM risk. Our study population consisted of 1,832 controls and 2,894 MM cases recruited from seven European countries and Israel in the context of the IMMEnSE (International Multiple Myeloma rESEarch) consortium. In this population two SNPs showed an association with p < 0.05: rs286595 (located in gene MRLP22) and rs14191881 (located in gene TCF19). Results from IMMEnSE were meta-analyzed with data from a previously published genome-wide association study (GWAS). The SNPs rs13409 (located in the 3'UTR of the POU5F1 gene), rs1419881 (TCF19), rs1049633, rs1049623 (both in DDR1) showed significant associations with MM risk. In conclusion, we sought to identify genetic polymorphisms associated with MM risk starting from genome-wide prediction of miRSNPs. For some mirSNPs, we have shown promising associations with MM risk.

The importance of the number of transplanted cells with dipeptidyl peptidase-4 expression on the haematopoietic recovery and lymphocyte reconstitution in patients with multiple myeloma after autologous haematopoietic stem-cell transplantation.

Autologous haematopoietic stem cell transplantation (AHSCT) remains recommended treatment in the first remission in multiple myeloma (MM). In earlier research it has been suggested that there is an influence of the expression of dipeptidyl peptidase-4 (CD26) on both the homing and lymphocyte reconstitution after AHSCT. The aim of the study is to investigate the influence of transplanted cells CD26+ on the haematopoietic recovery and lymphocyte reconstitution after AHSCT in MM. Forty eight patients with MM underwent AHSCT in our centre. Number of all CD26+ cells, CD26+ lymphocytes, CD26+ monocytes and CD26+ and CD34+ cells were measured in the harvested material. Number of lymphocyte's subpopulations (all lymphocytes CD3+, helpers, suppressors, natural killer (NK), cytotoxic NK and lymphocytes B) were measured in peripheral blood during regeneration after AHSCT. In both flow cytometry was used. On the basis of the analysis there was, as regards regeneration of haematopoietic cells after AHSCT, it was shown that a higher number of monocytes CD26+ improves the reconstitution of helper, suppressor and NK lymphocytes. A higher number of transplanted CD26+ lymphocytes accelerates the reconstitution of NK lymphocytes, whereas a higher number of all the cells CD26+ has a positive impact on the regeneration of cytotoxic NK lymphocytes. Copyright © 2015 John Wiley & Sons, Ltd.

Autologous hematopoietic stem cell transplantation (AHSCT) for aggressive multiple sclerosis - whom, when and how.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that leads to an inflammatory process resulting in demyelination and axonal degeneration. The most common form of MS is the relapsing-remitting MS (RRMS) characterized by the presence of numerous relapses. After few years of disease course, 90% of those patients eventually develop a secondary progressive form. About 10% of patients may suffer from a slowly progressive MS form - the primary progressive. The current treatment of RRMS includes immunomodulatory and immunosuppressive agents, which are effective, but usually in earlier and more benign forms. The immunomodulatory treatment has limited efficacy in aggressive forms of RRMS, and relapses occur despite treatment continuation. AHSCT should be considered as a therapeutic approach for patients with aggressive relapsing-remitting and aggressive progressive MS who failed conventional therapy. The mechanism of action of AHSCT for MS results from resetting the aberrant patient's immune system and eliminating the autoreactive T-lymphocytes. AHSCT can serve as an effective and safe procedure only when strict neurological eligibility criteria are adhered. The procedure should be performed in highly specialized hematological centers. The aim of our paper is to summarize the current eligibility criteria for AHSCT in MS patients as well as to present data on efficacy and safety of this approach.

Bendamustine as monotherapy and in combination regimens for the treatment of chronic lymphocytic leukemia and non-hodgkin lymphoma: a retrospective analysis.

BACKGROUND/AIM: In this study, we carried out a retrospective analysis of the efficacy and toxicity of bendamustine in patients with B-cell lymphoproliferative diseases. METHODS: Bendamustine was administered both as monotherapy and in combined protocols to 92 patients, including 76 patients with chronic lymphocytic leukemia (CLL) and 16 patients with indolent lymphomas. Bendamustine plus rituximab was used to treat 65.2% of the patients, and 34.8% of the patients received bendamustine as monotherapy. RESULTS: The overall response rate was 64.2%, including the complete response rate (18.5%) and the partial response rate (45.7%). The median overall survival (OS) was 11.5 months. Among the pretreatment parameters, ß2-microglobulin (RR = 1.413; p = 0.001) and hemoglobin levels (RR = 0.85; p = 0.03) significantly influenced survival. The OS was significantly longer in patients who received ≤2 lines of previous therapy compared to >3 lines (p = 0.043; log-rank test) and those who received ≥4 courses of therapy with bendamustine (p = 0.0007; log-rank test). Toxicity was predominantly hematological, including grade III/IV neutropenia in 33.7%, thrombocytopenia in 13%, and anemia in 13% of patients. CONCLUSION: Bendamustine, both in monotherapy and in combination regimens, is an effective therapy with a favorable toxicity profile in patients with indolent B-cell malignancies.

Autologous stem cell transplantation for mantle cell lymphoma - single centre experience.

AIM OF THE STUDY: Mantle cell lymphoma (MCL) is a B-cell neoplasm showing resistance to conventional chemotherapy. High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) may result in higher progression-free (PFS) and overall survival (OS) when used as a consolidation for younger and fit patients. MATERIAL AND METHODS: We retrospectively evaluated the results of ASCT for MCL. Patients were transplanted after achieving first or subsequent complete or partial response after conventional chemotherapy. RESULTS: Twenty patients (7 male and 13 female) at median age of 59 years (range 41-68) were included. 90% of transplanted patients had stage III/IV disease at diagnosis and low, intermediate and high MIPI scores occurred in 5, 9 and 6 patients respectively. Induction chemotherapy consisted of the R-CHOP regimen in all patients except one who received R-CVAD. The disease status at transplant was as follows: first complete response (n = 13); second complete response (n = 4) and partial response (n = 3). The conditioning regimen prior to ASCT consisted of CBV and BEAM for 18 and 2 patients, respectively. The transplant-related mortality was 0% at day 100. Median OS and PFS were 48 and 29.8 months, respectively. The estimated 5-year OS and PFS were found to be 52% and 35%, respectively. After median follow-up after ASCT of 36 months (range 11-73), 10 patients were alive with 8 remaining in complete remission (CR) whereas 2 relapsed and received salvage chemotherapy. Ten patients died from disease recurrence and subsequent chemoresistance. CONCLUSIONS: ASCT as a consolidation for MCL patients is found to be an effective and safe procedure.

Effect of transplanted cells with CD184 and CD26 expressions and reconstitution of CD3+ lymphocyte population on long-term survival after autologous hematopoietic stem cell transplantation for multiple myeloma.

Autologous hematopoietic stem cell transplantation (auto-SCT) is the recommended treatment for responding patients with multiple myeloma (MM). However, we do not know the risk factors influencing long-term survival without progression after auto-SCT. Therefore, this prospective study aimed to investigate the influence of transplanted cells with cluster of differentiation (CD)184+ expression, CD26+ lymphocytes and monocytes, and reconstitution of CD3+ lymphocytes on overall survival (OS) and progression-free survival (PFS) after auto-SCT in MM. Forty-eight patients with MM underwent auto-SCT at our center from 2011 to 2013. The numbers of CD184+ cells, CD26+ lymphocytes, and CD26+ monocytes were measured in the harvested material. In addition, the number of lymphocyte subpopulations (CD3+ lymphocytes, helpers, suppressors, natural killer (NK), cytotoxic NK, and B lymphocytes) was measured in peripheral blood during regeneration after auto-SCT. Flow cytometry was performed in both cases. The median OS was 92 months. Our analysis revealed a statistically significant effect of the number of transplanted CD184+ cells on OS and a statistically significant correlation between PFS and the number of transplanted CD184+ cells and reconstitution of CD3+ lymphocytes. In conclusion, our study showed that the increasing numbers of transplanted CD184+ cells, CD26+ lymphocytes, and CD26+ monocytes augmented the risk of death.

Pulmonary Complications After Allogeneic Hematopoietic Stem Cell Transplantation for Multiple Myeloma: A Case Report.

We present a case of a young patient with life-threatening pulmonary complications after allogeneic hematopoietic stem cell transplantation (HSCT). The 25-year-old woman, after HSCT for multiple myeloma, developed severe chronic graft-vs-host disease (GvHD), including bronchiolitis obliterans syndrome. During the treatment of chronic GvHD, 18 months after HSCT, she experienced sudden massive pulmonary hemorrhage with cardiac arrest. The computed tomography imaging revealed lesions suggestive of fungal etiology, with cavity adjacent to the pulmonary vessels. Disqualified from invasive treatment due to poor pulmonary performance, she was treated conservatively with broad-spectrum antibiotics and antifungals. The microbiological workup consistently revealed only Pseudomonas aeruginosa colonization. Her condition steadily improved on treatment. Over 18 months after the incident, she did not experience recurrent bleeding nor serious infection, her primary disease remains in remission, and GvHD symptoms are controlled. Allogeneic HSCT offers possibility of sustained immune-mediated disease control and sometimes even cure, but despite reduced transplant related mortality, GvHD and infections may be detrimental for transplant recipients. Our report illustrates atypical manifestation of pulmonary lesions and highlights the importance of infection control during GvHD treatment.

Cereblon (CRBN) gene polymorphisms predict clinical response and progression-free survival in relapsed/refractory multiple myeloma patients treated with lenalidomide: a pharmacogenetic study from the IMMEnSE consortium.

Cereblon (CRBN) is crucial for antiproliferative and immunomodulatory properties of immunomodulatory drugs. The objective of this study was to verify whether germline single nucleotide polymorphisms (SNPs) in the CRBN gene may influence response to lenalidomide in multiple myeloma (MM). Fourteen tagging SNPs covering the genetic variability in the CRBN gene region were genotyped in 167 Polish patients with refractory/relapsed MM treated with lenalidomide-based regimens. We found that carriers of minor alleles of two studied CRBN SNPs rs1714327G > C (OR = 0.26; 95% CI = 0.1-0.67; p = .0055, Bonferroni corrected p = .033) and rs1705814T > C (OR = 0.22; 95% CI = 0.07-0.65; p = .0063, Bonferroni corrected p = .037) were significantly associated with lower probability of achievement at least partial remission while treated with lenalidomide-based regimens, using the dominant inheritance model. Moreover, one of these SNPs, namely rs1705814T > C, was correlated with shorter progression-free survival (HR = 2.49; 95%CI = 1.31-4.74, p = .0054, Bonferroni corrected p = .033). It is suggested that selected germline CRBN allelic variants (rs1714327G > C and rs1705814T > C) affect lenalidomide efficacy in patients with relapsed/refractory MM.

Outcome of HLA-matched related allogeneic hematopoietic stem cell transplantation for patients with acute leukemia in first complete remission treated in Eastern European centers. Better results in recent years.

The goal of this study was to analyze results and to determine factors affecting outcome of HLA-matched hematopoetic stem cells transplantation (MRD-HSCT) for patients with acute leukemia transplanted in first complete remission in Eastern European countries. Six hundred forty HSCT were performed between 1990 and 2006 for adults with acute myeloid (n = 459) and lymphoblastic (n = 181) leukemia. Two-year leukemia-free survival (LFS), nonrelapse mortality (NRM), and relapse incidence were 58 +/- 2%, 19 +/- 2%, and 23 +/- 2%, respectively. The cumulative incidence of NRM decreased from 22 +/- 2% for patients treated between 1990 and 2002 to 15 +/- 3% for transplantations performed between 2003 and 2006 (p = 0.02), despite increasing recipient age. In a multivariate analysis, time of HSCT affected both NRM and LFS. Among other prognostic factors, the use of TBI decreased relapse incidence and increased the LFS rate. We conclude that results of MRD-HSCT for acute leukemia in Eastern Europe improved over time as a consequence of decreased NRM. The use of TBI containing regimens appears advantagous.

Activating killer immunoglobulin-like receptor incompatibilities enhance graft-versus-host disease and affect survival after allogeneic hematopoietic stem cell transplantation.

OBJECTIVES: Killer immunoglobulin-like receptors (KIRs) regulate function of natural killer (NK) cells and a subset of T cells. In this study, we prospectively evaluated the impact of donor and recipient activating KIR genes on outcome of allogeneic hematopoietic stem cell transplantation (alloHSCT) for patients with hematological malignancies. METHODS: One-hundred consecutive recipients of myeloablative transplantation and their donors were tested for KIR genotype as well as for immune reconstitution, including activating KIR expression on NK cells and T cells. RESULTS: In a multivariate analysis, mismatches of particular activating KIRs such that the patient was negative and the donor was positive (P-D+) resulted in increased risk of acute (KIR2DS1) and chronic (KIR2DS3) graft-versus-host disease (GVHD) as well as relapse (KIR2DS5). KIR2DS1 incompatibility in the same direction in the presence of HLA-C-group 2 ligand in recipient was associated with reduced overall (risk ratio, RR = 3.01; P = 0.01) and disease-free survival (RR = 2.92, P = 0.03). Activating mismatches in P-D+ direction resulted in decreased CD4+ : CD8+ T-cell ratio up to 1 yr after alloHSCT, as a consequence of decreased CD3+CD4+ number within the first 100 d and increased CD3+CD8+ number in later time-points. Among six evaluated patients, expression of activating KIRs on NK cells and T cells was particularly prominent for those developing intestinal GVHD. CONCLUSION: Our findings indicate that the presence of particular activating KIRs in donor with their absence in recipient enhances GVHD, which is not accompanied by graft-versus-leukemia effect. Evaluation of activating KIR genotype may allow optimization of both donor selection and transplantation procedure in order to avoid GVHD.

Treosulfan and fludarabine low-toxicity conditioning for allogeneic haematopoietic stem cell transplantation in chronic myeloid leukaemia.

Allogeneic haematopoietic stem cell transplantation (alloHSCT) is the only treatment of proven long-term efficacy in chronic myeloid leukaemia (CML), although high non-relapse mortality (NRM) observed after conventional myeloablative conditioning limits its applicability. This phase II trial evaluated the efficacy and toxicity of a new preparative regimen consisting of treosulfan 3 x 14 g/m(2) and fludarabine 5 x 30 mg/m(2), in patients with CML in chronic phase. Among the 40 patients included, 18 received alloHSCT from a sibling and 22 from an unrelated donor. All patients engrafted with 92.5% of cases achieving complete donor chimaerism by day +100. All but one patient had achieved complete cytogenetic remission on day +100. Grade III or IV non-haematological toxicities included: neutropenic fever (10%), nausea/vomiting (10%), elevated liver enzymes (5%) and infection (2.5%). The incidence of grade II-IV acute graft-versus-host disease (GVHD) was 22.5% and extensive chronic GVHD, 14%. The 2-year probability of overall survival, leukaemia-free survival and NRM was 85%, 82.5% and 15% respectively. At 1 year post-transplant, 85% of survivors had a Karnofsky index of 100%. We concluded that treosulfan and fludarabine conditioning is a low-toxicity regimen with high anti-leukaemic potential that seems feasible in CML patients referred for alloHSCT.

Status of minimal residual disease after induction predicts outcome in both standard and high-risk Ph-negative adult acute lymphoblastic leukaemia. The Polish Adult Leukemia Group ALL 4-2002 MRD Study.

The treatment of adults with Philadelphia-negative acute lymphoblastic leukaemia (ALL) depends on the presence of risk factors including age, white blood cell count, immunophenotype and time to complete remission. In recent years, status of minimal residual disease (MRD) has been postulated as an additional risk criterion. This study prospectively evaluated the significance of MRD. Patients were treated with a uniform Polish Adult Leukemia Group (PALG) 4-2002 protocol. MRD status was assessed after induction and consolidation by multiparametric flow cytometry. Out of 132 patients included (age, 17-60 years), 116 patients were suitable for analysis. MRD level >/=0.1% of bone marrow cells after induction was found to be a strong and independent predictor for relapse in the whole study population (P < 0.0001), as well as in the standard risk (SR, P = 0.0003) and high-risk (P = 0.008) groups. The impact of MRD after consolidation on outcome was not significant. The combination of MRD status with conventional risk stratification system identified a subgroup of patients allocated to the SR group with MRD <0.1% after induction who had a very low risk of relapse of 9% at 3 years as opposed to 71% in the remaining subjects (P = 0.001). We conclude that MRD evaluation after induction should be considered with conventional risk criteria for treatment decisions in adult ALL.

The incidence and risk factors for chronic graft-versus-host-disease.

OBJECTIVES: Chronic graft-versus-host-disease (cGVHD) deteriorates survival and quality of life after allogeneic hematopoietic cell transplantation (alloHCT). We evaluated the incidence and risk factors for this complication based on a single-center experience. METHODS: 255 consecutive patients, aged 29 (10-56) years, who survived without disease progression after alloHCT performed between 1992-2003 were included in the analysis. The preparative regimen was myeloablative, donors were either related (n=177) or unrelated volunteers (URD-HCT) (n=78). RESULTS: Cumulative incidence of the overall and extensive cGVHD equaled 48% and 22%, respectively. In a multivariate analysis the following factors were associated with increased risk of cGVHD: preceding grade II-IV acute GVHD, recipient age > or =40 years, URD-HCT, the diagnosis of chronic myeloid leukemia (CML) or myelodysplastic syndrome, and CD3 cell dose 50 x 10(6)/kg. Similar factors, excluding recipient age contributed to increased risk of extensive cGVHD, however, the cut-point for CD3 cell dose was 100 x l0(6)/kg and the use of steroids for acute GVHD prophylaxis was found an additional risk factor. In a CML subgroup the risk of cGVHD was increased for patients previously treated with interferon. CONCLUSIONS: Various recipient-, donor-, and procedure-related factors are related to the risk of cGVHD. Individualized treatment and modification of risk factors may contribute to improved outcome.

Acute graft-versus-host disease. The incidence and risk factors.

OBJECTIVES: Acute graft-versus-host-disease (aGvHD) is a major cause of mortality after allogeneic hematopoietic cell transplantation (alloHCT). The goal of this study was to evaluate the incidence and risk factors for this complication. METHODS: 330 consecutive patients (183 male and 147 female), aged 29 (10-56) years, treated with alloHCT in a single center between 1992-2003 were included in the analysis. AlloHCT was performed after myeloablative conditioning from either related donor (rel-HCT) (n=223) or unrelated voulnteer (URD-HCT) (n=107). GVHD prophylaxis consisted of cyclosporin, methotrexate +/- prednisolone. RESULTS: Cumulative incidence of grade II-IV and grade III-IV aGvHD equaled 31% and 17%, respectively. In multivariate analysis the following factors were associated with increased risk of grade II-IV aGvHD: the diagnosis of chronic myeloid leukemia (CML) or myelodysplastic syndrome (MDS) (vs. other diagnoses), URD-HCT (vs. Rel-HCT), years of alloHCT 1992-2001 (vs. 2002-2003), donor age > or =35 years, and CD34+ cell dose > or = 4.0 x 10(6)/kg. Increased risk of grade III-IV aGVHD was associated with: the use of prednisolone for aGvHD prophylaxis, the diagnosis of CML or MDS, and CD3+ cell dose > or =100 x l0(6)/kg. CONCLUSIONS: Incidence of aGvHD depends on various recipient-, donor-, and procedure-related factors. This should be taken into account when planning treatment for every individual patient.

Treosulfan, cyclophosphamide and antithymocyte globulin for allogeneic hematopoietic cell transplantation in acquired severe aplastic anemia.

To reduce the risk of graft rejection after allogeneic hematopoietic cell transplantation (alloHCT) for patients with acquired severe aplastic anemia (SAA), we introduced an intensified preparative regimen consisting of treosulfan 10 g/m2/d on days -7, -6, cyclophosphamide 40 mg/kg/d on days -5, -4, -3, -2 and anti-thymocyte globulin 2 mg/kg/d on days -3, -2, -1. Six patients with the history of multiple transfusions were treated with alloHCT from either HLA-identical sibling (n=3) or an unrelated volunteer (n=3). Each, bone marrow and peripheral blood was used as a source of stem cells in three cases. All patients engrafted and achieved complete donor chimerism. None of the patients experienced severe organ toxicity. No severe acute graft-versus-host-disease (GVHD) was observed; two patients experienced extensive chronic GVHD. At the median follow-up of 14.5 (13-27) months all patients remained alive and disease-free. Our observation indicates that treosulfan + cyclophosphamide + antithymocyte globulin conditioning is well-tolerated and allows stable engraftment in acquired SAA.

Safety and efficacy of hematopoietic stem cells mobilization in patients with multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is a T-cell-mediated chronic inflammatory disorder of the central nervous system. Several agents have been approved for the treatment of MS; however, their efficacy is limited and short term. Autologous hematopoietic stem cell (HSC) transplantation may remain an encouraging option for some MS patients who failed prior conventional treatment. Objective To assess the safety and effectiveness of HSCs mobilization in patients with MS. MATERIAL AND METHODS: Thirty-nine patients (20 females and 19 males) with relapsing-remitting MS at median age of 40 years (range: 25-63) were included in this study. As a stem cell mobilization, they received either granulocyte colony-stimulating factor (G-CSF) alone (10 µg/kg s.c. daily; n = 1) or cyclophosphamide (CY; 2.0 g/m(2) i.v. on days 1-2) followed by G-CSF (n = 38). RESULTS: The median number of mobilized HSCs per kg was 6.32 × 10(6) (range: 2.64-26.3 × 10(6)). One apheresis was sufficient for collection of HSCs in 30 out of 39 MS patients (77%). Two aphereses were required for seven patients, three for one and four for one (17, 3, and 3%; respectively). Side effects of HSCs mobilization have been reported for eight patients (30%) and they were following: Staphylococcus epidermidis bacteremia (n = 1), fever of unknown origin (n = 3), diarrhea (n = 3), and headache (n = 1). CONCLUSIONS: Mobilization using CY and/or G-CSF resulted in effective mobilization in all MS patients. This procedure was found to be safe. No fatal outcome has been reported.

Successful treatment of pure red cell aplasia with repeated, low doses of rituximab in two patients after ABO-incompatible allogeneic haematopoietic stem cell transplantation for acute myeloid leukaemia.

We describe two patients with acute myeloid leukemia successfully treated with anti-CD20 antibody for pure red cell aplasia (PRCA) following ABO-mismatched allogeneic hematopoietic stem cell transplantation (HSCT). PRCA following HSCT is associated with major ABO incompatibility between donor and recipient and is due to an inhibition of donor erythroid precursors by residual host isoagglutinins. The first patient developed PRCA resistant to several treatment options including donor-derived leukocyte infusions (DLI), high-dose erythropoietin (EPO), and rapid tapering of cyclosporin A (CsA). This patient also received anti-viral therapy as CMV and parvovirus B19 infections were regarded as additional causes of PRCA. Due to a loss of donor chimerism, he underwent second HSCT, but PRCA still persisted. He showed no evidence of graft-versus-host disease (GVHD). Finally he was administered anti-CD20 antibody (rituximab) at a dose of 150/m2 and PRCA resolved in a short period of time. The case was complicated by life-threatening pulmonary aspergillosis with septic shock, successfully treated with anti-fungal therapy. The second case concerns a patient, who revealed PRCA after major ABO-incompatible HSCT from his brother. Considering our experience with the previously described patient, he proceeded to rituximab at a dose of 150/m2 as first line treatment. We observed rapid recovery from PRCA without any side effects. We conclude that rituximab seems to be a promising therapeutic option in patients with PRCA after ABO-mismatched HSCT, in whom conventional treatment fails.

The impact of immunosuppressive therapy on an early quantitative NK cell reconstitution after allogeneic haematopoietic cell transplantation.

OBJECTIVES: The goal of this study was to examine the impact of various immunosuppressive regimens on an early NK cell recovery following haematopoietic cell transplantation (alloHCT). METHODS: The number of peripheral blood NK cells was analysed with the use of flow cytometry on day +30 (+/-2) after alloHCT from an HLA identical sibling (n=43) or an unrelated (n=34) donor. RESULTS: Patients receiving prednisolone as a prophylaxis of acute graft-versus-host disease had lower number of NK cells compared to those not given steroids prophylactically (110(10-694) vs. 212(33-890) x 10(6)/L, p = 0.005). In contrast, administration of anti-thymocyte globulin (ATG) (7.5-15 mg/kg) as a part of preparative regimen was not found to influence the NK cell recovery. Similarly, no effect on the number of peripheral blood NK cells was observed with regard to other analysed factors: cell dose, type of myeloablative conditioning, source of stem cells, patient and donor characteristics, number of post-transplant methotrexate doses. CONCLUSIONS: Immunosuppressive therapy may affect NK cell recovery following alloHCT. Since NK cells are considered a potential tool for cellular therapy of haematological malignancies, our findings should be taken into account when planning this kind of treatment in the context of allotransplantation.