Effect of human adipose-derived mesenchymal stem-C on the differentiation of monocytes

The ideal stem cell for use in functional tissue engineering needs to be abundantly available, harvested with minimal morbidity, differentiated reliably down various pathways and able to be transplanted safely and efficaciously. Adult human adipose tissue contains a population of mesenchymal stem cells; adipose-derived stem cells, which seem to fulfil most, if not all, of these criteria. In this work, we investigated the immunogenicity properties of human adipose-derived mesenchymal stem cells [HAMSCs] and their effect on monocytes differentiation. The HAMSCs have been isolated and specified. Human peripheral blood mononuclear cells [PBMCs] were isolated and passed through a column with magnetic beads coated with anti-CD14 antibody. CD14+ ve cells were isolated and cultured independently or co-cultured with HAMSCs in the presence of cytokines [IL-4, Granulocyte-macrophage colony-stimulating factor [GM-CSF]] to induce their differentiation into dendritic cells [DCs]. Their further maturation was induced by LPS added on the 6[th] day of culture. The major part of the independently cultured cells [CD14+ ve] was found to express the markers which are considered to be specific for the mature dendritic cells such as Human leukocyte antigen-DR [HLA-DR] [40.44%] and low percentage of cells [6.9%]. Nevertheless dendritic cells of monocyte origin [mDCs] co-cultured with HAMSCs showed significant shifts in the pattern of surface markers. The percentage of HLA-DR cells was much lower [6.44%] compared to control cultures [p < 0.001]. Similarly, the secretion of IL-10 by DCs was up-regulated in co-cultures of HAMSCs and DCs. The results show that human adipose-tissue mesenchymal stem cells [HAMSCs] could inhibit the differentiation of the blood monocytes into dendritic cells

Effect of different collagenase digestion protocols on the yield and function of adult rat islets

A comparison was performed among 4 different digestion techniques of adult rat pancreas, with a trial to reduce both the concentration of collagenase [1 mg/mg], the time of digestion [10 min] and the use of NYcodenz as density gradient medium. It was concluded that to obtain a high yield of islets, pancreas distension and stationary digestion technique are more recommended than mincing or multiple injections with Hank's solution or collagenase. About 500 islets per rat pancreas could be obtained after 20 min incubation, but the shorter the incubation period the better long-term function of cultured islets. Islets resulted after short-time digestion are not suitable for immediate transplantation because of contamination with some exocrine tissue, but suit long-term culture and transplantation after culture