[Biological characteristics of rabbit bone marrow mesenchymal stem cells and their response to different growth factors].

This study was aimed to analyze the biological characteristics of rabbit bone marrow mesenchymal stem cells (rBM-MSCs) and their response to different growth factors. Rabbit BM-MSCs were separated from bone marrow mononuclear cells by using adherent cultivation. Biological characteristics were investigated by optical and electron microscopy. Immunophenotype of rBM-MSCs was measured by flow cytometry. The expression of collagen was detected by RT-PCR. Differentiation potential was identified by specific staining and RT-PCR. The response of rBM-MSCs to IL-1, 3, 8 and HGF with different concentrations were tested by MTT. The results showed that the rBM-MSCs gave rise to a population of adherent cells characterized by the presence of a predominant cell type with a typical fibroblast-like morphology and could be cultured for over 15 passages. CD44 was highly expressed on F5 rBM-MSCs (32%) and CD45 was lowly expressed (4.7%). Type I collagen was highly expressed, while type II collagen was lowly expressed and type X collagen was not detected on rBM-MSCs using RT-PCR method. In various conditions inducting differentiation, rBM-MSCs could differentiate into the osteoblast, chondrocyte, adipocyte and neuron-like cells. The rBM-MSCs were sensitive to IL-3, even low concentration (10 ng/ml) of IL-3 could promote the proliferation of rBM-MSCs effectively (>32%, P < 0.01), whereas high concentration IL-3 inhibited it significantly. It is concluded that rabbit BM-MSCs were successfully isolated and culture-expanded. The biological characteristics of rabbit BM-MSCs are similar to those of human and rhesus BM-MSCs. IL-3 with low concentration can promote the proliferation of rBM-MSCs effectively, but high concentration of IL-3 can inhibit their proliferation.