منیره محمد

In spite of promising results in treatment of blood diseases by umbilical cord blood cell transplantation, low number of derived stem cells has been a matter of concern. Since platelets extracts has been introduced as a potent mesenchymal stem cell culture supplement, the purpose of current study was to investigate the probable effects of umbilical cord blood platelet lysate (UCB-PL) in proliferation, survival and differentiation of cord blood mononuclear cells.
The umbilical cord blood platelet lysate (UCB-PL) was added to cord blood mononuclear cells culture (1×10 6 /mL) in presence of FLT3L, TPO and SCF. The effective dose of UCB-PL, cell viability and differentiation of mononuclear cells were determined by trypan blue staining and colony assay method, respectively. The number of mononuclear cells was measured by flowcytometric analysis of CD133 CD34࠽ cells. Quantitative expression of CD 34 was performed by QRT-PCR method.
Combination of 5% of UCB-PL with mentioned cytokines yielded a 12-fold cell proliferation in comparison with control group. A higher concentration of UCB-PL showed cytotoxic effects. CD 34 also increased significantly in group of 5% UCB-PL treated cells. In this particular group, a significant increase of colony forming units granulocytes-erythroidmacrophages-megakaryocyte (CFU-GMMM) and granulocyte-macrophage (CFU-GM) were detected.
Our results indicate that 5% UCB -PL can be used as a supplement in MNC cultured cells and in cord blood hematopoietic stem cells for cell therapy purposes.

The evaluation of the number، potential، and functional capacity of cord blood stem cells after long term storage is essential for their therapeutic uses in hematological malignancies and non-malignancies. Therefore، this study was aimed to assess the quality of cord blood units stored in Royan public cord blood bank، before and after cryopreservation. To check the quality of cryopreserverd cord blood units، the total number of cells، percentage of viable cells، colony-forming ability، the number of CD34+ cells before and after freezing were examined on 50 samples Our results determined that the mean value of the total nucleated cells in 50 cord blood samples was 7. 6 × 108 ± 1. 12 × 108. The number and viability of mononuclear cells as well as colony forming potential significantly decreased after cryopreservation; however، the count of viable CD34+ cells did not significant changes post thawing. There was no significant correlation between the numbers of nucleated cells and CD34+ cells. Increasing the storage time significantly reduces the number of nucleated cells and differentiation potential of hematopoietic stem cells rather than the number of CD34+ cells. Improved cryopreservation techniques are necessary to maintain the function of cord blood stem cells.

The production of a sufficient number of pancreatic endocrine cells that function similarly to primary islets is one of the methods in treatment of diabetes. The CD133+ cells derived from cord blood (UCB-CD133) express some embryo specific markers such as SSEA-4 and OCT4 and so it can be a candidate for differentiation into insulin secreting cells. Therefore, here we attempt to determine the differentiation potential of UCB-CD133+ cells into insulin secreting cells in vitro. UCB-CD133+ cells were isolated by MACS and differentiated into insulin secreting cells using the medium containing DMEM/F12, bFGF, Nicotinamid, and supplement B27 N2 for 9 days. The expression of insulin and c-peptide protein was detected by immonocytochemistry. The expression of insulin, Nkx6.1, Pdx1, and Glocagon genes was analyzed by RT-PCR; ELISA was performed to analysis the function of differentiated cells in different glucose concentrations (5 and 27 mM). Our results determined that UCB-CD133+ cells expressed insulin and c-peptide at protein level after 9 days of culture. However, the insulin, Nkx6.1, Pdx1, and Glocagon genes were not detected in differentiated cells and they could not respond to different concentrations of glucose. We suggested that UCB-CD133+ cells can differentiate into insulin secreting cells in vitro; however, they are not functional and need to receive more signals in vivo.

Background and ObjectivesUmbilical cord blood has been used successfully as a source of hematopoietic stem cells for transplantation. Knowing that cord blood could be bacterially contaminated at the time it is being obtained and afterwards during the time it is being processed, we decided to perform the present study to determine any possible bacterial contamination and find out the root causes in Royan Cord Blood Bank (RCBB). Materials and MethodsRCBB during 3 years received 3074 cord blood units (CBUs) upon which relevant investigation was made. In order to determine the root cause of the bacterial contamination, 800 CBUs were tested out of each of which two samples were taken. The data were analyzed with Chi-square by SPSS 16. ResultsOut of 3074 CBUs, 93 units (3.02%, CI 95%=2.3-3.6) were shown to have bacterial contamination. Out of the 800 units tested to detect the root cause, 26 samples (3.3%) were proved to be bacterial culture positive out of which 25 (96.2%) were shown to be contaminated at the time they were obtained and 1 (3.8%) during processing. The isolated bacteria were aerobic in 19 cases (73.1%) and anaerobic in 7 (26.9%). ConclusionsThe results show that bacterial contamination mostly is caused at the time blood is obtained from the cord in hospital obstetrics wards and most of the isolated bacteria were shown to be skin flora. Given the high value of cord blood stem cells and the risk of septic transplantation, it is necessary to prepare training programs for midwives and phlebotomists.