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M G KOENIG

Publications and source records attributed to M G KOENIG.

13 recordsLinked to original sources

THE DYNAMICS OF RETICULOENDOTHELIAL BLOCKADE.

The dynamics of "reticuloendothelial blockade" were studied in living rabbits and isolated, perfused rabbit livers utilizing gelatin as a blockading agent and Au(198) stabilized in gelatin as a tracer. Employing the above experimental model, the following observations were made. (a) RES blockade was specific and dependent on the surface properties of the particle under study. (b) RES blockade was not caused by saturation of hepatic removal mechanisms. (c) RES blockade was not caused by depletion of demonstrable serum opsonins. (d) RES blockade appeared to correlate with high circulating levels of the blockading agent, per se. Thus, under the conditions employed, the term "reticuloendothelial blockade" was a misnomer. Although specificity of liver macrophage-particle interaction was evident and deserves further study, the data suggest that blockade as usually studied is a laboratory phenomenon induced by the continuing circulation of the blockading agent.

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Factors relating to the virulence of Staphylococci. II. Observations on four mouse-pathogenic strains.

Four clumping factor-negative strains of Staphylococcus aureus were found to closely resemble the diffuse colonial variant of the Smith strain. All produced fatal intraperitoneal infections in mice, all grew in diffuse, streaming colonies in plasma or serum soft agar, and all behaved like encapsulated microorganisms in in vitro opsonic systems. These staphylococci were resistant to phagocytosis in the peritoneal cavities of normal mice. When mice were immunized with heat-killed vaccines prepared from the Smith diffuse variant these strains were rapidly ingested by peritoneal leukocytes and the animals survived. This observation suggests that these strains share the same or a similar phagocytosis-retarding antigen. While most pathogenic staphylococci isolated from human material do not behave like these unusual mouse-virulent strains, indirect evidence is cited to support the suggestion that other staphylococci may acquire similar phagocytosis-resisting characteristics during in vivo multiplication. Studies to support or refute this thesis are in progress.

Animals↗

Factors relating to the virulence of Staphylococci. III. Antibacterial versus antioxic immunity.

Antitoxic and antibacterial immunity have been clearly differentiated in the experimental mouse infection produced by the diffuse colonial variant of the Smith strain of Staphylococcus aureus. Immunization with crude toxoid protected mice from otherwise lethal doses of alpha hemolysin, but did not alter mortality following intraperitoneal infection with living staphylococci. Conversely, animals immunized with heat killed vaccines were readily killed by culture supernates containing alpha hemolysin, but were strikingly protected from otherwise fatal intraperitoneal infection with viable staphylococci. Protection was directly related to the ability of the immunizing substance to promote early intraperitoneal phagocytosis of the infecting inoculum. In these studies with the Smith diffuse variant, rapid intraperitoneal phagocytosis was induced by vaccination with whole cell bacterial vaccines but not by alpha hemolysin toxoid.

Animals↗