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Peripheral blood stem cell cryopreservation is associated with cell damage and decreased viability. We evaluated the impact of up to 10 years of cryopreservation (5% DMSO) on viability of CD34+ cells utilizing graft samples of consecutive patients (2002-2012) with different malignancies who underwent stem cell collection and transplantation. Viability of CD34+ cells from oncohaematological patients measured after 5 weeks (97·2 ± 0·6%) or after 9-10 years of cryopreservation (95·9 ± 0·5%) was unaffected. Haemoglobin, granulocyte and platelet recovery after transplantation of long-term cryopreserved grafts occurred within 8-13 days. CD34+ stem cells can be safely stored up to 9-10 years, without affecting cell viability and clinical effectiveness. [ABSTRACT FROM AUTHOR]

Background and Objectives Autologous peripheral blood stem cell transplantation has recently become a standard therapeutic approach to virus-related or infected haematological malignancies. Collection, manipulation, storage and thawing of leukapheresis products in this subset of patients require strict monitoring to prevent infection risk for operators and risk of contamination for other stored bags. Materials and Methods This is a non-randomized retrospective observational study. In the 2000–2002 period, a single bag freezing procedure was used for autologous peripheral blood stem cell transplantation. Bags were stored in tanks containing liquid and gas phase nitrogen. In 2002, the processing procedure was revised, and a second additional safety bag and a new storage tank containing jacketed liquid nitrogen have been used. Results A total of 524 bags were thawed, of which 121 processed with the single bag method and 403 with the double bag method. Forty-nine and 109 patients were infused respectively. The observed rupture rate with the single bag in liquid and gas phase nitrogen was 17 and 2·5%, respectively, against a rupture rate as little as 0·24% with the new methodology. Viability revealed levels of 84·4% ± 6·1% and 96·9% ± 2·4% for the single and double-bag respectively. This statistically significant ( P < 0·0001) difference correlated with better neutrophil engraftment. Conclusions The new proposed method, based on a double bag and storage freezer without liquid or gas phase nitrogen into a cryogenic chamber, significantly reduces bag rupture and bio-hazard and improves stem cell viability and neutrophil engraftment remarkably. [ABSTRACT FROM AUTHOR]

Background and Objectives Ex vivo peripheral blood progenitor cell (PBPC) expansion has been proposed as a strategy to increase the number of haematopoietic progenitors available for cell transplantation. We have expanded CD34+ cells from PBPCs obtained from four patients with haematological malignancies and one patient with an Ewing's sarcoma. Materials and Methods Cells were expanded in the Dideco ‘Pluricell system’. After 12 days in culture, we evaluated cell phenotype, total nucleated cells, CD34+ fold increase, cell apoptosis and colony assay of expanded cells. Cell engraftment has been evaluated by transplanting two groups of irradiated non-obese diabetic/severe combined immunodeficient (NOD-SCID) mice with expanded and non-expanded cell populations. Results Total nucleated cells and CD34+ cells increased 59·5 and 4·0 times, respectively. The expanded cells were mainly constituted of myeloid and megakaryocytic cells. A significant increase in the number of colony-forming unit–granulocyte macrophage (CFU-GM) was observed in the CFU assay. Ten mice transplanted with expanded cells showed a best overall survival (80%) compared to 10 mice transplanted with non-expanded cells (20%). Human CD45+ cells were detected by flow cytometry and polymerase chain reaction in bone marrow and spleen of transplanted animals. The relative low engraftment level obtained with the expanded cells suggests a loss of SCID repopulating cells maybe due to cell differentiation during expansion. Conclusions We have demonstrated the feasibility of the ex vivo expansion of mobilized PBPCs from cancer patients, evidencing a clonal expansion of CFUs and the ability of the expanded cells to engraft the bone marrow and spleen of immunosuppressed mice. The differentiation of the CD34+ stem cell compartment could be further minimized by ameliorating the expansion conditions. [ABSTRACT FROM AUTHOR]

The effects of CD34 mobilization with chemotherapy and G-CSF administration were evaluated in 13 HIV-positive patients with relapsed lymphomas and low CD4 counts. After mobilization, CD4+ cells increased significantly while HIV-RNA and integrated HIV-DNA showed no increases. G-CSF led to an increase of CD4+ cells with limited effects on HIV replication.

Cases of B-cell chronic lymphocytic leukaemia (B-CLL) with mutated (M) IgV(H) genes have a better prognosis than unmutated (UM) cases. We analysed the IgV(H) mutational status of B-CLL according to the features of a canonical somatic hypermutation (SHM) process, correlating this data with survival. In a series of 141 B-CLLs, 124 cases were examined for IgV(H) gene per cent mutations and skewing of replacement/silent mutations in the framework/complementarity-determining regions as evidence of antigen-driven selection; this identified three B-CLL subsets: significantly mutated (sM), with evidence of antigen-driven selection, not significantly mutated (nsM) and UM, without such evidence and IgV(H) gene per cent mutations above or below the 2% cut-off. sM B-CLL patients had longer survival within the good prognosis subgroup that had more than 2% mutations of IgV(H) genes. sM, nsM and UM B-CLL were also characterized for the biased usage of IgV(H) families, intraclonal IgV(H) gene diversification, preference of mutations to target-specific nucleotides or hotspots, and for the expression of enzymes involved in SHM (translesion DNA polymerase zeta and eta and activation-induced cytidine deaminase). These findings indicate the activation of a canonical SHM process in nsM and sM B-CLLs and underscore the role of the antigen in defining the specific clinical and biological features of B-CLL.

Different transformation mechanisms have been proposed for elderly acute myeloid leukaemia (AML) and secondary AML (sAML) when compared with de novo AML or AML of younger patients. However, little is known regarding differences in the immunophenotypic profile of blast cells in these diseases. We systematically analysed, by flow cytometry, 148 patients affected by de novo (100 cases) or sAML (48 cases). By defining a cut-off level of 20% of CD34+ cells co-expressing CD90, the frequency of CD90+ cases was higher in sAML (40%) versus de novo AML (6%, P < 0.001), elderly AML (>60 years) (24%) versus AML of younger patients (10%, P = 0.010) and poor- versus good-risk karyotypes (according to the Medical Research Council classification, P < 0.001). The correlation between CD90 expression, sAML and unfavourable karyotypes was confirmed by analysing the subset of CD34+ AML cases alone (91/148). Consistently, univariate analysis showed that expression of CD90 was statistically relevant in predicting a shorter survival in CD90+ AML patients (P = 0.042). Our results, demonstrating CD90 expression in AML with unfavourable clinical and biological features, suggest an origin of these diseases from a CD90-expressing haemopoietic progenitor and indicate the use of CD90 as an additional marker of prognostic value in AML.

Hepatosplenic gammadelta+ T-cell lymphoma represents a rare neoplasm of post-thymic phenotype, characterized by an aggressive clinical course and a poor response to conventional chemotherapy. In the present study, we have examined the cytotoxic effects of the purine analogue 2'-deoxycoformycin (dCF) on cultured mononuclear cells and purified gammadelta+ tumour cells from bone marrow or peripheral blood of four patients with hepatosplenic gammadelta+ T-cell lymphoma. At a concentration of 10 microM, dCF, in the presence of 2'-deoxyadenosine (dAdo), displayed an early and selective cytotoxic effect on gammadelta+ tumour T cells. After 48 h of in vitro exposure to dCF, the absolute number of viable CD3+/gammadelta+ tumour T cells was reduced by more than 90% in all samples with respect to control cultures, with absolute counts of viable CD3+/alphabeta+ lymphocytes being reduced only by 6-40% of the initial cell input. Analysis of cultures after 5 d of exposure to dCF plus dAdo revealed the persistence of normal CD3+/alphabeta+ T cells, which accounted, however, for only 20-25% of the initial cell input. Accordingly, the combination of dCF (10-100 microM) plus dAdo was able to induce a dose-dependent inhibition of clonogenic growth and [3H]-thymidine incorporation in purified CD3+/CD4-/CD8- gammadelta+ tumour cells. We also report that one patient with hepatosplenic gammadelta+ T-cell lymphoma in terminal leukaemic phase showed a striking haematological response to single-agent dCF given as fourth-line treatment. In particular, the selective clearance of gammadelta+ tumour T cells in peripheral blood and bone marrow was observed starting after the second course of treatment. Our results suggest that dCF may represent a potentially active drug for the management of this aggressive form of T-cell lymphoma.