Effect of staphylococcal protein A on pro-inflammatory cytokines expression in mononuclear macrophage / 重庆医学

ABSTRACT

Objective To study the expression and regulation of pro‐inflammatory cytokinesTNF‐α,IL‐1 ,IL‐6 in mononucle‐ar macrophages stimulated with staphylococcal protein A (SpA) .Methods THP‐1 was incubated with PMA and induced into mononuclear macrophages .Then the macrophages were incubated with varying concentrations of SpA under different time points . The effect of SpA on macrophage proliferation was measured by MTT method .The levels of inflammatory cytokines ,TNF‐α,IL‐1 and IL‐6 from the cultured cell media were measured by ELISA respectively .The levels of mRNA expression corresponding to TNF‐α,IL‐1 and IL‐6 were detected by RT‐PCR from the macrophages stimulated with SpA .All statistical analyses were performed by SPSS17 .0 software .Results The MTT result indicated that SpA had a positive effect on the proliferation of THP‐1 cells in a dosage depended manner .The addition of SpA could enhance the mRNA expression of TNF‐α,IL‐1 and IL‐6 in the stimulated mac‐rophages .It also showed a specific dose‐effect and time‐effect correlation .The macrophages secreted inflammatory cytokines and its corresponding mRNA reached its peak levels at 12 h post stimulation .Compared with the control group ,the expression and release of TNF‐α,IL‐1 and IL‐6 in macrophages from the experimental group was increased with statistical significance(P<0 .01) .Conclu‐sion SpA can promote the secretion and expression of early pro‐inflammatory cytokines ,such as TNF‐α,IL‐1 and IL‐6 in macro‐phages .Therefore ,SpA plays a very important role in the initiation and development of the staphylococcus aureus sepsis .