| Objective:To explore the function of the cytokine of hTGF-β1 on the mouse lymphocytes stimulated by polyclonal stimuli, and of the pEGFP-hTGF-β1-N1 on rat rib growth-plate chondrocytes. And to provide a method for ideal seed cells of cartilage-tissue engineering and prevention or therapy of transplantation rejection.Methods:The expression of CD69 and CD25 of mouse T lymphocytes stimulated by IVTGF-β1 and polyclonal stimuli was determinated by flow cytometry. Annexin V/7-AAD staining was used together with FACS to assess percentage of apoptosis of lymphocytes. And the proliferation of lymphocytes was determinated by 3H-TdR. Chondrocytes were transfected with pEGFP-hTGF-β1-N1 expression vector and the green fluorescence of pEGFP were detected with flow cytometry and fluorescent microscope. The biological function of chondrocytes were detected by isotope incorporation.Results:The expression of CD69 and CD25 of lymphocytes costimulated with hTGF-β1 and polyclonal stimuli was no change, the incorporation of 3H-TdR was lower than control group and the percentage of Annexin V single positive cells, which indicated lymphocyte apoptosis, was higher than control group. And the expression of pEGFP-TGF-β1-N1 fusion protein could be detected with flow cytometry. The fluorescene was distributed in the cytoplasma and around the nucleolus.The biologicalfunction of chondrocytes transfected with pEGFP-TGF-β1-N1 expression vector, including proliferation of chondrocytes, synthesis of type- II collagen and aggrecan was enhanced.Conclusions:The decreased proliferation rate but no change of activation of lymphocytes gave us the clue that hTGF-β1 may prevent lymphocytes to enter S stage from Gl stage. But the mechanism of increased apoptosis of lymphocytes needs further be explored. And pEGFP-TGF-β1-N1 gene could be expressed in rat chondrocytes efficiently. The mechanism of the enhanced biological of chondrocytes transfected with hTGF-β1 may be the phosphorylation of c-Jun-NH2-terminal kinase(JNK). |
