[Regulatory effects of streptococcal protein on the immunologic activity of RAW264.7 murine macrophages.].
OBJECTIVE
To investigate the regulatory effects and the related mechanisms of streptococcal protein on the immunologic activity of RAW264.7 murine macrophages.


METHODS
RAW264.7 cells were incubated with different concentrated streptococcal protein respectively. The proliferation of RAW264.7 cells was determined by MTT assay. The phagocytosis of macrophages was analyzed by neutral red phagocytosis assay. The activities of IL-6 and TNF-alpha in the cultured supernatants were measured by bio-chemical methods. The mRNA expression of TNF-alpha, IL-6 and Toll-like receptors (TLRs) in cells was detected by reverse transcription polymerase chain reaction (RT-PCR). The expression of TLR2 and TLR4 in peritoneal cells was measured by flow cytometry.


RESULTS
Streptococcal protein significantly enhanced the activities of proliferation and phagocytosis of macrophages (P<0.05), induced the release of IL-6, TNF-alpha and the expression of IL-6, TNF-alpha mRNA (P<0.05).The streptococcal protein, meanwhile, also up-regulated the expression of TLR2 and TLR4 in macrophages in vitro (P<0.05).


CONCLUSIONS
Streptococcal protein may promote proliferation, phagocytosis and cytokines production in regulation of the activity of murine macrophages.
Wang
Yan
Y
Department of Pathogenic Biology, Capital Medical University, Beijing 100069, China.
Li
Qin
Q
Wang
Yi-Song
YS
Chen
Hui
H
Zheng
Qun
Q
Ping
Guo-Ling
GL
Zhang
Li-Ping
LP
D000818:Animals; D015850:Interleukin-6 / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D051195:Toll-Like Receptor 2 / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D015850:Interleukin-6; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha