Interleukin-6 in Sera of Mice Inoculated with Group A Streptococcus and Cultural Supernatants.

Dynamics of IL-6 level was studied in blood serum of CBA mice receiving intraperitoneal injections of killed and live culture of group A Streptococcus and its supernatants. It was found that administration of killed culture was followed by a significant rise in IL-6 level (by 4.7 times in 1 h and by 9.3 times in 5 h in comparison with the control). By 24 h, cytokine content was below the control. The highest levels of IL-6 were found after treatment with supernatants of Streptococcus cultures (by 10.5 times in 1 h and by 14.9 times in 5 h, in comparison with the control). Administration of live culture was accompanied by an increase in IL-6 concentration by 3.2 times in 3 h. In this experimental series, the maximum level of IL-6 was found in 48 h (by 5.2 times), and then it gradually decreased below the control. Different dynamics of changes in IL-6 level after administration of killed and live cultures of group A Streptococcus may suggests that they activate different signal pathways.