Functional verification of vimentin as an alarmin / 中国免疫学杂志

ABSTRACT

Objective:To identify the function of extracellular soluble vimentin that promotes proliferation, activation and chemotaxis of inflammatory cells. Methods: The proliferation of rat splenocytes stimulated with vimentin was evaluated in vitro. The lymphocyte counts and vimentin-antibody levels of peripheral blood in mice immunized with vimentin were detected in vivo. Peritoneal macrophages were collected and cultured with different concentrations of vimentin to detect the effect on phagocytosing chicken red blood cells. The chemotaxis of NIH3T3 fibroblast towards vimentin was observed in transwell chamber. Results:In vitro vimentin dose dependently promoted the proliferation of splenocytes. The proliferation indexes of primed and naive splenocytes cultured with 16μg/ml vimentin were reached up to ( 196. 0 ± 9. 7 )% and ( 208. 9 ± 4. 6 )% respectively without significant difference. In vivo vimentin significantly enhanced the lymphocytes number(109 L-1)of peripheral blood(5. 74±0. 51 vs. 1. 69±0. 13)and the levels of vimentin specific antibody( OD value 2. 31 ± 0. 06 vs. 0. 19 ± 0. 08 ) that shown no significant difference from immunization with vimentin plus CFA. In vitro vimentin dose dependently stimulated phagocytic ability of macrophages and performed the chemotactic effects on NIH3T3 fibroblasts. Conclusion:Extracellular soluble vimentin promotes the proliferation,activation and chemotaxis of concerned inflammatory cells and possesses the functions as an alarmin.