Mahsa Rahmani; Hamid Reza Khorasani; Monireh Golpour; Ali Shabestani Monfared; Hosein Nattaj; Saeeid Abedian; Amrollah Mostafazadeh
Volume 13, Issue 1 , March 2016, , Pages 54-63
Abstract
Background: The human leukocyte antigen (HLA) matching between organ donor and recipient is an acceptable strategy in clinical transplantation since 1964. However, in bone marrow transplantation, finding matched donors is often problematic. Thus new method for down regulation of HLA can be an alternative ...
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Background: The human leukocyte antigen (HLA) matching between organ donor and recipient is an acceptable strategy in clinical transplantation since 1964. However, in bone marrow transplantation, finding matched donors is often problematic. Thus new method for down regulation of HLA can be an alternative strategy to solve this problem. Objective: To examine the effect of serum starvation on HLA class I expression in human peripheral blood mononuclear cells (PBMCs). Methods: PBMCs were cultured in RPMI-1640 supplemented with 10% FBS (non-starved cells) as well as in medium only (starved cells) for 16, 24, 48, 72, 96h under standard cell culture conditions. The pattern of cell death and HLA class I expression was determined by flowcytometry. Antigenicity of the starved PBMCs was evaluated in a one-way mixed lymphocyte culture by MTT assay. Results: Mean fluorescence intensity (MFI) of different indicated starved PBMCs gradually decreased and this reduction was stable after 96h of re-feeding with medium containing FBS. Under serum starvation condition, PBMCs showed apoptotic cell death pattern. There was a linear correlation between percentages of cells, which exhibited the late apoptosis death pattern and serum starvation period (r=0.88, p<0.01). Surprisingly, the starved PBMCs lost their stimulatory property in mixed culture with allo-reactive lymphocyte. Conclusions: Membrane HLA class I expression could be stably reduced in 96h starved human PBMCs culture condition, decreasing their allo-reactivity while their viability rate is enough for possible clinical application.
Hasan Ebrahimi; Masoud Soleimani; Mohammad Kazemi Arabadadi; Naser Ajmadbeigi; Gholamhossein Hassanshahi; Akbar Farjadfar; Derek Kennedy
Volume 7, Issue 1 , March 2010, , Pages 30-38
Abstract
Background: Unrestricted somatic stem cells (USSC) are cord blood stem cells that have been considered as candidates for the regulation of immune responses. Therefore, potential exists for their use in the suppression of immune response after transplantation surgery. Objective: The aim of this study ...
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Background: Unrestricted somatic stem cells (USSC) are cord blood stem cells that have been considered as candidates for the regulation of immune responses. Therefore, potential exists for their use in the suppression of immune response after transplantation surgery. Objective: The aim of this study was evaluation of the effect of USSC on mixed lymphocyte reaction (MLR) as a model for graft rejection. Methods: USSC and mesanchymal stem cells (MSC) were isolated and cultured from cord blood and bone morrow, respectively. The immunophenotypes of USSC and MSC were evaluated by flow cytometery and USSC and MSC were co-cultured with peripheral blood lympho-cytes (PBL) in an MLR to evaluate the immunomodulatory effect of these cells as a percentage of the control response. Results: Current study demonstrated that prolifera-tion of lymphocytes in the MLR was decreased after treatment with USSC, in a similar fashion to that seen with MSC. Conclusion: It can be concluded that USSC have simi-lar regulatory effects as MSC on the MLR, which can be used as an indicator for poten-tial organ rejection after transplantation. Therefore, the immunregulatory effect of these cells could be used in the clinic during organ transplantation and in the management of autoimmunity.
Behrouz Nikbin; Mandana Mohyeddin Bonab; Fatemeh Talebian
Volume 2, Issue 4 , December 2005, , Pages 232-240
Abstract
Tissue and cell transplantation are regarded as a popular procedure in clinical sciences, prospecting a new horizon for several incurable diseases. Along with its usefulness, many ethical concerns accompany this development. The ethical issue of organ transplant is unique to the source used which includes: ...
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Tissue and cell transplantation are regarded as a popular procedure in clinical sciences, prospecting a new horizon for several incurable diseases. Along with its usefulness, many ethical concerns accompany this development. The ethical issue of organ transplant is unique to the source used which includes: living related, living unrelated, cadaveric, and xenotransplant. Obtaining organs has a separate set of ethical concerns which are discussed under two headings, namely salvage and donation. Then there is the issue of organ marketing and the ethical, social, and economical issues it encompasses. All these are active areas of debate, and we have touched upon them by turn. This century has brought a new aspect of transplantation into the light, stem cell transplantation. Here we present some work done recently on mesenchymal stem cells and their outcome. These cells are now being employed in the therapy of some incurable ailments. It seems this kind of transplantation, although possessing its own range of issues, could prove to be the way of the future.
Behrouz Nikbin; Nader Tajik; Ali Saraji; Gholam Reza Pourmand; Fatemeh Talebian; Abdurasul Mehrsai; Ali Akbar Amirzargar
Volume 1, Issue 3 , December 2004, , Pages 162-168
Abstract
Background: The Presence of donor leukocytes in recipients of organ allograft has been shown even several years after transplantation. However, it remains unclear whether this donor cell microchimerism plays an effective role in allograft acceptance or is simply a consequence of immunosuppressive conditions ...
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Background: The Presence of donor leukocytes in recipients of organ allograft has been shown even several years after transplantation. However, it remains unclear whether this donor cell microchimerism plays an effective role in allograft acceptance or is simply a consequence of immunosuppressive conditions in recipients. Objective: To study microchimerism in a group of kidney transplant recipients. Methods: In this study, the Peripheral Blood Microchimerism (PBM) after renal transplantation was retrospectively evaluated in 32 male-to-female recipients of living (unrelated) and cadaveric donor renal transplants. Using a Nested Polymerase Chain Reaction (Nested-PCR) amplification specific for SRY region of the Y chromosome, microchimerism was detected with a sensitivity of 1:1000000. Recipients were classified and compared according to the presence of PBM, acute and chronic rejection episodes, type of allotransplant, recipient and donor age at transplantation, previous male labor or blood transfusion, allograft function (serum creatinine level), and body mass index. Results: Among 32 recipients, 7 (21.9) were positive for PBM in multiple testing at different post-transplantation times. All microchimeric recipients had received kidney from living-unrelated donors. No significant difference was observed with regard to other parameters mentioned above. In addition, acute rejection rate in the microchimeric group was 3 (42%) versus 4 (16%) in the nonmicrochimeric recipients (not significant). Conclusion: Our results demonstrate better establishment of microchimerism after living donor kidney transplantation. However, concerning the true effect of microchimerism after renal transplantation doubt still persists; and it seems that microchimerism alone has no major protective role in renal allograft survival.