间充质的干细胞的隔离和描述源于人的胎盘组织

AIM: To explore the feasibility of placenta tissue as a reliable and efficient source for generating mesenchymal stem cells (MSC). METHODS: MSC were generated from human placenta tissue by enzymatic digestion and mechanical dissociation. The placenta MSC (PLC-MSC) were characterized for expression of cell surface markers, embryonic stem cell (ECS) gene expression and their differentiation ability into adipocytes and osteocytes. The immunosuppressive properties of PLC-MSC on resting and phytohemagglutinin (PHA) stimulated allogenic T cells were assessed by means of cell proliferation via incorporation of tritium thymidine (3H-TdR). RESULTS: The generated PLC-MSC appeared as spindle-shaped cells, expressed common MSC surface markers and ESC transcriptional factors. They also differen-tiated into adipogenic and osteogenic lineages when induced. However, continuous cultivation up to passage 15 caused changes in morphological appearance and cellular senescence, although the stem cell nature of their protein expression was unchanged. In terms of their immunosuppressive properties, PLC-MSC were unable to stimulate resting T cell proliferation; they inhibited the PHA stimulated T cells in a dose dependent manner through cell to cell contact. In our study, MSC generated from human placenta exhibited similar mesenchymal cell surface markers; MSC-like gene expression pattern and MSC-like differentiation potential were comparable to other sources of MSC. CONCLUSION: We suggest that placenta tissues can serve as an alternative source of MSC for future experimental and clinical studies.

Preliminary study on overproduction of reactive oxygen species by neutrophils in diabetes mellitus

AIM:To assess the amount and pattern of reactive oxygen species(ROS)production in diabetic patientderived neutrophils.METHODS:Blood samples from type 2 diabetes mellitus(DM)patients and volunteers(controls)were subjected to neutrophil isolation and the assessment of neutrophil oxidative burst using chemiluminescence assay.Neutrophils were activated by using phorbol myristate acetate(PMA)and neutrophils without activation were kept as a negative control.The chemilu-minescence readings were obtained by transferring cell suspension into a 1.5 m L Eppendorf tube,with PMA and luminol.Reaction mixtures were gently vortexed and placed inside luminometer for a duration of 5 min.RESULTS:Our results showed that in the resting condition,the secretion of ROS in normal non-diabetic individuals was relatively low compared to diabetic patients.However,the time scale observation revealed that the secreted ROS declined accordingly with time in non-diabetic individuals,yet such a reduction was not detected in diabetic patients where at all the time points,the secretion of ROS was maintained at similar magnitudes.This preliminary study demonstrated that ROS production was significantly higher in patients with DM compared to non-diabetic subjects in both resting and activated conditions.CONCLUSION:The respiratory burst activity of neutrophils could be affected by DM and the elevation of ROS production might be an aggravating factor in diabetic-related complications.