RÉSUMÉ
BACKGROUND: Immune function of chemotaxis signal has been a key focus in medical research. However, the immune activation and related action mechanism of chemotatic factor RANTES are unclear.OBJECTIVE: To investigate the immune activation and related action mechanism of chemotatic factor RANTES stimulation on peripheral mononuclear cells.DESIGN: Control Experiment.SETTING: Department of Urologic Surgery, Clinical Medical College, Yangzhou University.MATERIALS: The experiment was performed at the Laboratory of Department of Immunology, University of Louisville from December 2004 to August 2005. Main reagent and equipments included RPMI 1640 complete medium, recombinant human RANTES, anti-CD3 monoclonal antibody, pyrrolidine dithiocarbamate(PDTC),CTLA4Ig, LS500 liquid scintillation counter and FACS Epics XL flow cytometry.METHODS: Peripheral mononuclear cells were collected and stimulated by different concentrations of recombinant human RANTES and/or anti-CD3 monoclonal antibody. Cells with significantly proliferative response were intervened by pyrrolidine dithiocarbamate (PDTC) or CTLA4lg. 3H-thymidine incorporation was used to detect the proliferation of mononuclear cells. Flow cytometry was applied to measure the phenotypes of lymphocytes.MAIN OUTCOME MEASURES: Incorporation efficiency of 3H-thymidine, the ratio of CD4 to CD8, expression of CD25,CCR5 and CD28.RESULTS: Proliferative reaction of mononuclear cells reached two peaks with recombinant human RANTES concentrations of 100 μg/L and 5000 μg/L respectively. The proliferation of peripheral mononuclear cells stimulated by 100 μg/L recombinant human RNATES was significantly higher than that in the presence of 50 μg/L anti-CD3 monoclonal antibody (P<0.05).There were no rivalry or synergistic effect between them.The immune active effects of recombinant human RANTES could be inhibited by PDTC or CTLA,Ig in a dose dependent manner.After RANTES treatment,the level of cell surface CD25 increased (P<0.05) and the CCR5 expression decreased (P<0.05), but there were no significant differences in CD28 expression and the ratio of CD4/CD8 of lymphocytes(P>0.05).CONCLUSION: RANTES has a specific function of inducing the immune activation of mononuclear cells. This special signal works depending on the activation of interleukin-2 signal pathway, CD28 co-stimulatory pathway and nuclear factor-κB,but independent of CD3 activation.
RÉSUMÉ
Objective To investigate the proliferation and phenotypes of peripheral mononuclear cells (PMNC) stimulated by recombinant human RANTES (rhRANTES) and the mechanisms involved.Methods PMNC was stimulated by various concentrations of rhRANTES and/or anti-CD3 mAb and intervened by PDTC and CTLA4Ig. Scintillation counter was used to count the cpm of proliferation cells and flow cytometry was used to detect the phenotypes of lymphocytes.Results rhRANTES was capable of directly stimulating purified human PMNC proliferation and two peaks occurred with rhRANTES concentration of 100 ng/ml and 5000 ng/ml respectively. The proliferation of PMNC stimulated by rhRNATES was significantly higher than that in the presence of anti-CD3mAb (P
RÉSUMÉ
Objective To investigate the implication of lymphotactin (LTN) mRNA expression in cardiac allografts and the effect of cyclosporin A (CsA).Methods Three groups of rats underwent the heterotopic cardiac transplantation: isograft group (group A), untreated group (group B) and CsA treated group (group C). The LTN mRNA expression was detected by one step RT PCR method. Results The expression of LTN mRNA was not detected in both isografts and normal hearts. The changes of LTN mRNA expression were correlated with the process of acute allograft rejection. The peak of elevated level of the LTN mRNA expression appeared in the 5th day after transplantation and CsA could delay the peak and downregulate its expression. The peak level of LTN mRNA expression in group C was significantly lower than that in group B ( P