Çiğdem Akalin Akkök

Hematopoietic engraftment of dimethyl sulfoxide-depleted autologous peripheral blood progenitor cells

BACKGROUND: Autologous stem cell transplantation with cryopreserved autografts is a prerequisite for high‐dose chemotherapy in treatment of several malignancies. Adverse effects due to the cryoprotectant dimethyl sulfoxide (DMSO) vary from mild to severe. DMSO‐associated adverse effects can be reduced by DMSO depletion before autograft infusion. The aim was to investigate whether DMSO depletion by manual single wash reduced frequency of adverse effects or had detrimental effects on the engraftment potential of peripheral blood progenitor cell (PBPC) autografts.

Autologous peripheral blood progenitor cells cryopreserved with 5 and 10 percent dimethyl sulfoxide alone give comparable hematopoietic reconstitution after transplantation

BACKGROUND: Previous in vitro studies have demonstrated decreased apoptosis and necrosis in peripheral blood progenitor cells (PBPCs) cryopreserved with 5 percent instead of 10 percent dimethyl sulfoxide (DMSO). This study was carried out to investigate whether these in vitro findings were supported by clinical data concerning hematopoietic engraftment after autologous stem cell transplantations with PBPCs cryopreserved with 5 and 10 percent DMSO.

Use of different DMSO concentrations for cryopreservation of autologous peripheral blood stem cell grafts does not have any major impact on levels of leukocyte- and platelet-derived soluble mediators.

BACKGROUND AIMS Infusion of stem cell autografts can be associated with adverse effects. Necrotic normal leukocytes, cytokines or intracellular mediators released from leukocytes and platelets or the cryo-protectant dimethyl sulfoxide (DMSO) may contribute to this. Cryopreservation using 5% instead of 10% DMSO improves CD34(+) cell viability and therefore we investigated whether using less DMSO had favorable outcomes on leukocyte viability and levels of various soluble mediators in the graft supernatant. METHODS Peripheral blood autografts were harvested by 20 apheresis procedures in 16 cancer patients, and autograft samples were cryopreserved with 2%, 4%, 5% and 10% DMSO and stored for 5-6 years. After thawing, the viability of neutrophils and lymphocytes was analyzed by flow cytometry and supernatant levels of soluble mediators were determined by enzyme-linked immunosorbent assay (ELISA) analyzes. RESULTS The highest viability of both neutrophils and lymphocytes was detected with 4% and 5% DMSO, whereas decreased viability was observed with 2% and 10% DMSO. Low or undetectable levels of leukocyte-derived interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha and CXCL8, high levels of platelet-derived CCL5 and CXCL4, and high levels of monocyte-derived soluble CD14 were measured independent of the DMSO concentration, except for slightly increased CXCL8 and decreased CXCL4 levels with 2% DMSO. Perforin levels showed a significant inverse correlation with the DMSO concentration. CONCLUSIONS The use of different DMSO concentrations affects the viability of normal leukocytes in autologous peripheral blood stem cell grafts, but has only minor effects on supernatant levels of leukocyte- and platelet-derived soluble mediators.

Is there a scientific basis for a recommended standardization of collection and cryopreservation of peripheral blood stem cell grafts

High-dose chemotherapy followed by autologous stem cell transplantation has been used extensively during the last two decades in the treatment of hematologic malignancies. The vast majority of recent transplantations have been performed using mobilized peripheral blood stem cells, because they have become the preferred source of hematopoietic cells rather than bone marrow stem cells. The mobilization is achieved by growth factors, eventually combined with chemotherapy, and the cells are then harvested and cryopreserved until reinfusion. Despite extensive use for many years, few attempts have been made to standardize the various steps in mobilization, harvesting and cryopreservation. Furthermore, the autografts only represent relative stem cell enrichment and contain a wide range of more mature hematopoietic and immunocompetent cells; the potential clinical importance of these normal cells is largely unknown and represents an additional non-standardized factor in this treatment. We have reviewed the various methodologic approaches for stem cell mobilization, collection and cryopreservation of autografts with a special focus on the cryopreservation procedures, immunocompetent cells in the graft, and cytokine content of the graft supernatant. We conclude that the factors/aspects mentioned above should be standardized in future clinical studies of autotransplantation for human hematologic malignancies. Alternatively, detailed methodologic descriptions should be required when the results are published. Standardization of autograft preparation and cryopreservation will be achieved if/when transplantation units assess and adopt new standards based not only on the technology but, more importantly, on the quality of evidence and data related to that technology/methodology.

Maternal IgG anti-A and anti-B titres predict outcome in ABO-incompatibility in the neonate.

Aim:  To evaluate predictors for risk of severe hyperbilirubinaemia and kernicterus in ABO‐incompatible neonates with emphasize on maternal IgG anti‐A/‐B titres.

Effects of peripheral blood stem cell apheresis on systemic cytokine levels in patients with multiple myeloma.

BACKGROUND AIMS. Pro-angiogenic cytokines can affect myeloma cell proliferation directly and indirectly through stimulation of cancer-associated angiogenesis. METHODS. We investigated how peripheral blood stem cell (PBSC) collection affected plasma angioregulatory cytokine levels in 15 consecutive myeloma patients. RESULTS. Plasma levels of hepatocyte growth factor (HGF) were significantly increased prior to apheresis in patients compared with donors, and a further increase was detected immediately after PBSC apheresis. HGF levels decreased within 24 h, but were still higher than the levels in healthy donors, whose HGF levels were not altered by platelet apheresis. Pre-apheresis levels of other angioregulatory cytokines, angiopoietin-2 and vascular endothelial growth factor (VEGF), were also increased in patients, whereas angiopoietin-1, angiogenin and basic fibroblast growth factor levels did not differ from healthy controls. PBSC harvesting decreased angiopoietin-1 and VEGF levels, increased the microvascular endothelial cell marker endocan levels but did not affect the other mediators. CONCLUSIONS. Our results show that PBSC apheresis alters systemic angioregulatory profiles in myeloma patients. This cytokine modulation is not a general characteristic of all apheresis procedures and was not seen in healthy platelet donors.

One-year protocol biopsies from ABO-incompatible renal allografts compared with a matched cohort of ABO-compatible allografts

Early acute antibody‐mediated rejection (ABMR) occurs more frequently in ABO‐incompatible (ABOi) than in ABO‐compatible (ABOc) kidney transplantation. This could lead to increased inflammation/scarring in the ABOi grafts. Protocol biopsy data in ABOi kidney recipients are scarce.

Biological response modifiers in photochemically pathogen-reduced versus untreated apheresis platelet concentrates.

BACKGROUND: Lipids and other biologically active substances accumulate in platelet concentrates (PCs) during storage. Some of these substances have been suggested to modulate immune responses and to play a pathogenic role in the development of transfusion‐related acute lung injury. This study compared the content and impact of some biological response modifiers in PCs treated with pathogen reduction (PR) technology and nontreated PCs.

Stem cell mobilization and harvesting by leukapheresis alters systemic cytokine levels in patients with multiple myeloma

BACKGROUND AIMS Stem cell mobilization and harvesting by peripheral blood leukapheresis in patients with myeloma can alter plasma levels of certain cytokines. In the present study, we investigated the effects of these interventions on a larger group of cytokines. METHODS Plasma cytokine levels were determined in 15 patients with myeloma who were undergoing peripheral blood stem cell harvesting, and we compared the patients with healthy donors who were undergoing platelet apheresis. RESULTS Several cytokines showed altered levels in patients with myeloma when examined after chemotherapy plus granulocyte colony-stimulating factor-induced stem cell mobilization. The most striking effect was increased levels of several CCL (CCL2/3/4) and CXCL (CXCL5/8/10/11) chemokines as well as increased thrombopoietin, interleukin 1 receptor antagonist, interleukin-4, granulocyte colony-stimulating factor and hepatocyte growth factor. Stem cell harvesting by apheresis altered the plasma levels of several mediators (CD40 ligand, interleukin 1 receptor antagonist, CCL5 and CXCL5/8/10/11). Apheresis in patients with myeloma had divergent effects on these chemokine levels, although they were all still significantly higher than for healthy individuals. Thrombapheresis in healthy individuals had only minor effects on plasma cytokine levels. Stem cell graft supernatants showed high levels of several cytokines, especially CCL and CXCL chemokines. Analyses of chemokine profiles in pre-apheresis plasma and graft supernatants suggested that such profiling can be used to detect prognostically relevant differences between patients. CONCLUSIONS Our results demonstrate that patients with myeloma have an altered cytokine network during stem cell mobilization, and the network is further altered during stem cell harvesting by leukapheresis. These treatment- or procedure-induced alterations involve several mediators known to affect myeloma cell proliferation, migration and survival.

Severe hemolytic transfusion reaction due to anti-A1 following allogeneic stem cell transplantation with minor ABO incompatibility

Blood components should be compatible both with the recipient and the donor in the ABO incompatible allogeneic stem cell transplantation setting. A patient with blood type A2 received peripheral blood stem cells from a blood type O donor. The patient was in critical condition due to treatment-related toxicity. He had acquired anti-A1 that was unfortunately overlooked. Following transfusion of A1 red blood cells in error, he developed a severe hemolytic transfusion reaction. Anti-A1 is rarely clinically significant. We discuss the role of passenger lymphocytes in development of the anti-A1, and stress the importance of investigating unusual/atypical reactions in blood typing.