Marzieh Ebrahimi; Zuhair Mohammad Hassan; Jamshid Hadjati; Parisa Hayat; Seyed Mohammad Moazzeni
Volume 6, Issue 3 , September 2009, , Pages 107-118
Abstract
Background: Tumor necrosis factor alpha (TNF-α) is a primary mediator of immune regulation and might be required in the early stages of DC development from CD34+ cells. However, details of optimal timing of exposure to TNF-α in DC development process in monocytes or non-purified hematopoitic ...
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Background: Tumor necrosis factor alpha (TNF-α) is a primary mediator of immune regulation and might be required in the early stages of DC development from CD34+ cells. However, details of optimal timing of exposure to TNF-α in DC development process in monocytes or non-purified hematopoitic cells are still lacking and clear benefits of this approach to the development of DCs remain to be validated. Objective: To evaluate the effect of early and late exposure to TNF-α on DC devel-opment from non-purified cord blood mononuclear cells. Methods: To define the ef-fects of early exposure to TNF-α on cord blood mononuclear cells, we cultured UCB-MNC in the presence of SCF, Flt3L, GM-CSF and IL-4 for 14 days and matured them for an extra 4 days. TNF-α was added on day 0, 7 and 14 in TNF-α + group, and only on day 14 in TNF-α - group where it was used only as a maturation factor. Results: Immediate exposure to TNF-α was shown to: (1) enhance the survival of cells in the first week of culture; (2) produce mature DCs with higher maturation markers (CD80, CD83, CD86 and HLA-DR); and (3) increase secretion of IL-12 by mature DCs. In contrast, delayed exposure to TNF-α stimulate mature DCs with less purity producing a high level of IL-10 and a low level of IL-12. Conclusion: We developed a simple, easy and cost effective method to generate DCs from non-fractionating mononuclear cells in this study. Also we confirm the presence of a large number of functional DCs under inflammatory conditions, where local concentrations of TNF-α were high.
Andisheh Ghashghaie Mansour; Seyyed Hamidollah Ghaffari; Kamran Ali-moghadam; Ardeshir Ghavamzadeh
Volume 3, Issue 2 , June 2006, , Pages 95-98
Abstract
Background: HLA compatibility between transplant donor and recipient is one of the major determinants of transplant outcome. Objective: To determine HLA class I by PCR- Sequence-Specific Oligonucleotide Probe (PCR-SSOP) in cord blood donors. Methods: Genomic DNA of 142 cord blood samples registered ...
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Background: HLA compatibility between transplant donor and recipient is one of the major determinants of transplant outcome. Objective: To determine HLA class I by PCR- Sequence-Specific Oligonucleotide Probe (PCR-SSOP) in cord blood donors. Methods: Genomic DNA of 142 cord blood samples registered at the Cord Blood Bank of Iran at Hematology, Oncology, and Bone Marrow Transplantation Research Center, was prepared and HLA class I was determined by the PCR-SSOP. Results: A total of 284 HLA-A alleles was identified of which A*02 and A*24 were the most common. Among 284 HLA-B and HLA-C alleles, B*35, B*51, Cw*4 and Cw*12 were the most frequent alleles in the studied population. Conclusion: Amplification of HLA loci with PCR-SSOP has proved to be a reliable method for HLA-A, -B and -C genotyping.
Nahid Naderi; Ali Akbar Pourfathoolah; Mahin Nikougoftar; Kamran Alimoghadam; Ardeshir Ghavamzadeh; Seyed Mohammad Moazzeni
Volume 2, Issue 1 , March 2005, , Pages 21-28
Abstract
Background: Dendritic cells (DCs) are the most potent stimulators of primary T cell responses and play a key role in immune reactions after stem cell transplantation. Very little is known about the cord blood (CB) dendritic cells and their potential involvement in the low incidence and lower severity ...
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Background: Dendritic cells (DCs) are the most potent stimulators of primary T cell responses and play a key role in immune reactions after stem cell transplantation. Very little is known about the cord blood (CB) dendritic cells and their potential involvement in the low incidence and lower severity of acute graft-versus-host disease after CB transplantation. Objectives: The aim of this study was the isolation of cord blood and peripheral blood dendritic cells and comparison of their functional competence and determination of their probable role in graft versus host disease after stem cell transplantation. Methods: In this study, fresh peripheral blood DCs (PBDCs) were enriched as HLA-DR + cells, lacking the CD3, CD11b, CD14, CD16, CD19 and CD56, using immunomagnetic bead depletion. For cord blood dendritic cells (CBDCs) enrichment CD34 + and CD66b+ cells were needed to be depleted too. Immunomagnetically enriched PB/CB dendritic cells were co-cultured with adult T lymphocytes and cell proliferation was measured by 3H-thymidine incorporation. Results: Results showed that CBDCs were significantly poor stimulators of the mixed leukocyte reaction as compared with PBDCs (P < 0.05). Conclusion: The demonstrated impairment of CBDCs function could be of importance in interpretation of the low incidence and milder severity of graft-versus-host disease (GVHD) in umbilical CB transplantation compared with peripheral blood or bone marrow stem cell transplantation.
