On the Toxin for Leukocytes Produced by Streptococci (Streptoleukocidin)

Y. Nakayama
1920 Journal of Infectious Diseases  
Ruediger 1 found that the filtrates of virulent streptococcus cultures might suspend the destruction of nonvirulent streptococci by leukocytes. A little later, from observations on the appearance of leukocytes during phagocytosis in vitro, Hektoen 2 made this statement: So far as our observations have extended centrifugated culture fluids of virulent streptococci, staphylococci and anthrax bacilli reduce phagocytosis of the corresponding nonvirulent strains, principally, I believe, through
more » ... t action on the leukocytes, because the fluids in question have but a comparatively slight inhibitive or destructive effect on the opsonin in normal serum, but reduce greatly by one hour's contact the phagocytic power of leukocytes with respect to previously sensitized bacteria. In full harmony with this loss in phagocytic power are the marked functional and morphologic disturbances in the leukocytes placed in fluid containing the products of the growth of virulent bacteria. Thus, when leukocytes are placed in the culture fluids of a virulent streptococcus and examined from time to time on the warm stage, they are seen to lose ameboid movement and to swell greatly in from 30 to 60 minutes, whereas the leukocytes in control experiments remain normal in form and motion several times as long." M'Leod 3 noted a leukocidal effect of certain streptococci in rabbits in vivo, but he did not succeed in demonstrating any leukocidal action with streptococcal filtrates. From these observations it may be concluded that virulent streptococci or their culture fluids may have an unfavorable action on leukocytes, but the subject apparently has not been studied systematically. BACT-ERIAL LEUKOCIDIN Generally speaking, the production by bacteria of substances that are toxic for leukocytes has received little attention with the exception of the leukocidin produced by staphylococci. Van de Velde ' injected clear filtrates of 24-hour cultures of Staph. aureus in the pleural cavity of rabbits and found that the leukocytes changed, the nuclei becoming distinct and ameboid movement lost. When leukocytes were added to the filtrate in a test tube and left in the incubator for 24 hours, the same result was obtained. He named this toxic sub-
doi:10.1093/infdis/27.1.86 fatcat:hycrbgedsfgplhnfh3eqgvwi6u