The Lack of Bactericidal Effect of Mouse Blood for Nonvirulent Group A Streptococci

[摘要] Mouse blood in in vitro bactericidal tests is unable to sterilize even a small inoculum of certain group A streptococcal strains (327W and Type 1) which, on intraperitoneal injection into intact mice are shown to be of very low virulence. By contrast human blood is highly effective. The difference in growth-promoting properties of mouse and human blood appears to play no important role in this difference, nor does the relatively low neutrophil density of mouse blood.Evidence is presented suggesting that the slowness of ingestion of streptococci by mouse neutrophils (allowing extracellular proliferation to proceed relatively unchecked) is an important factor contributing to the poor bactericidal power of mouse blood. However, the existence of a strain that is readily phagocytized, the growth of which is only moderately inhibited by mouse blood suggests that factors other than ingestion rate are concerned.

[学科分类] 生物科学（综合）