Protective Effect of Hyaluronidase and Type-Specific Anti-M Serum on Experimental Group a Streptococcus Infections in Mice

When Group A streptococci are mixed with human blood under appropriate conditions in vitro, the bacteria are rapidly engulfed and killed by leucocytes. Among the conditions (1) required for this reaction are: (a) sufficiently large numbers of leucocytes, (b) complement and perhaps other serum or plasma factors, (c) an efficient mixing system to ensure adequate opportunity for contact between the white cells and streptococci, and (d) type-specific antibody, which is necessary for phagocytosis only in the case of streptococcal strains containing M protein.Efforts to develop an opsonophagocytic test for Group A streptococci, employing rabbit or mouse blood, have been "unsuccessful. The lack of bactericidal action in blood of these animals has been attributed by some to failure of the leucocytes to kill engulfed microorganisms (2, 3), while others have implicated deficiencies in plasma factors and inadequate phagocytosis (1, 4). Furthermore, recent studies have demonstrated that the differences between rabbit and human blood are not entirely consistent in this regard; blood from certain apparently healthy human beings is not satisfactory for use in the bactericidal test on streptococci, while on rare occasions a rabbit is found whose blood serves quite well for this purpose (5).This communication presents studies on interactions between polymorphonuclear leucocytes and Group A streptococci in vitro. The results indicate that under certain conditions an anti-phagocytic effect is exerted by the streptococcal hyaluronic acid capsule as well as by M protein. All human plasma or serum specimens thus far studied contain a factor, apparently neither enzyme nor antibody in nature, which counteracts the phagocytosis-resisting action of the capsule. In contrast, rabbit serum appears to be devoid of this factor. MethodsPeritoneal exudates were collected from adult New Zealand Red rabbits by a technique previously described (6), with slight modifications. The essential features of this procedure were as follows. Three hundred ml. of sterile isotonic saline containing 1 rag. per ml. glycogen *

Section: Discussionsupporting

confidence: 82%

Studies of Phagocytosis of Group a Streptococci by Polymorphonuclear Leucocytes in Vitro

Hirsch

Church

1960

“…Experiments are now in progress to demonstrate that the protein isolated here is antigenic, inducing the formation in rabbits of type-specific precipitins and protective antibodies. The need for elucidating the characteristics of M protein is obvious, since the evidence strongly suggests that it contributes to the virulence of Group A hemolytic streptococci in natural infections of man (28)(29)(30)(31), and in experimental infections of animals (32)(33)(34)(35).…”

Section: Discussionmentioning

confidence: 99%

Studies on the Bacteriophages of Hemolytic Streptococci

Krause

1958

The lysis of cell walls of hemolytic streptococci by a phage-associated lysin has been described. A method is presented for preparing the lysin from Group C streptococcal phage lysates. Following lysis almost all of the cell wall carbohydrate is recovered in solution. This material has the serological reactivity, physical-chemical properties, and values for nitrogen, rhamnose, and glucosamine similar to those of the carbohydrate isolated from the cell walls by the Streptomyces albus enzyme. Group C carbohydrate isolated by either enzyme inactivates Group C bacteriophage. The protein liberated by the lysin from Group A Type 6 cell walls gives a type-specific precipitin reaction with homologous rabbit antiserum. Preliminary data are presented on the ammonium sulfate fractionation and the electrophoretic separation of a protein fraction with the serological reactivity of M protein.

“…Although the in vi~o observations of Bordet, Marchand, and WaUgren, which related virulence to phagocytosis, have been confirmed (7), phagocytic experiments performed in vitro have yielded results which are difficult to interpret for the followLug reasons: (a) the strains of streptococci studied have often been inadequately characterized in regard to their content of cellular components known to be antiphagocytic (7)(8)(9), (b) the tests have usually been performed in the presence of "normal" serum which may or may not contain "natural" opsonins (7)(8)(9)(10)(11)(12)(13), and (c) the cells used in the phagocytic tests have, with but rare exceptions, been obtained from species of hosts other than those in which the virulence has been measured (7)(8)(9)(10)(11)(12)(13). Recently Wiley and Wilson (12) have emphasized the failure of in vitro phagocytic tests, as customarily performed, to reveal phagocyte-bacterium relationships which correlate directly with streptococcal virulence.…”

Section: Plates 36 To 39mentioning

confidence: 99%

“…The first of these, the antigenic M protein, has been extensively studied, particularly by Lancefield (14). Its presence on the surface of the streptococcal cell appears to render the organism resistant to phagocytosis (9,(11)(12)(13)(14), and specific antibodies to it will protect the host (14). The second factor, the non-antigenic (1) hyaluronic acid capsule, has been less exhaustively investigated, but it too has been shown to possess antiphagocytic properties (9,11,13).…”

Section: Plates 36 To 39mentioning

confidence: 99%

Studies on the Pathogenicity of Group a Streptococci

Foley

Smith

Wood

1959

Four strains of Group A streptococci, possessing different degrees of virulence for both mice and rats, were tested for susceptibility to phagocytosis on glass slides, in glass roller tubes, and on the surfaces of freshly excised tissues and moistened filter paper. All of the tests were performed in the absence of serum to exclude the possible presence of opsonins. Only under conditions which allowed surface phagocytosis to take place was there a correlation between virulence and susceptibility to phagocytosis. A similar relationship between virulence and surface phagocytosis was also demonstrable in vivo during the early stages of experimental streptococcal peritonitis. Systematic study of the evolution of the peritonitis revealed that its outcome was determined by the phagocytic reaction which occurred in the first few hours of the infection.