A Comparison of the Immunogenicity of Weakly Encapsulated and of Strongly Encapsulated Strains of Cryptococcus Neoformans (Torula Histolytica)

Neill, James M.; Abrahams, Irving; Kapros, Charles E.

doi:10.1128/jb.59.2.263-275.1950

Cited by 47 publications

(8 citation statements)

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“…The observation that opsonins for these rare encapsulated strains are present in normal adult human sera has led to the hypothesis that capsule formation might occur in vivo in the course of infection or colonization with staphylococci. Loss of the capsule during culture on artificial media, a phenomenon which has been shown to occur with other encapsulated organisms (3,15,16,22), could explain the infrequent isolation of encapsulated staphylococci from clinical sources.…”

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confidence: 99%

Biological Properties of the Encapsulated Staphylococcus aureus M

et al. 1974

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Strain M, classified as a Staphylococcus aureus, behaves like the other rare encapsulated staphylococcal strains. It was clumping-factor negative, grew in diffuse-type colonies in serum-soft agar, and produced rapidly fatal disease in mice. Strain M was highly resistant to phagocytosis by human or mouse leukocytes and required both specific antibody and heat-labile serum factor(s) for efficient ingestion by human polymorphonuclear leukocytes. Electron micrographs confirmed the presence of a large capsule. Agglutination studies, active or passive mouse protection experiments, and opsonic studies revealed that strain M represents a new, immunologically distinct strain of encapsulated staphylococcus. Strain M differs from other known encapsulated staphylococci in several other respects: its cellular and colonial morphology is atypical; its LD50 in the mouse peritoneal model is 100 times less than that of other mouse lethal strains; it is poorly opsonized by normal human serum; and, finally, it possesses an unusually large capsule as seen in electron micrographs. MATERIALS AND METHODS Cultures. Strain M. This encapsulated strain was isolated from a human infection in 1962 and has been described by Scott (20). The organism (NCTC 10649) was obtained from the National Collection of Type J. Bacteriol, in press). Smith diffuse. This variant has been previously described and has been used extensively as the prototype of an encapsulated mouse-virulent staphylococcus in this laboratory (9). T mutant. This is a mutant of S. aureus H possessing an additional surface polysaccharide antigen (24). The organism was kindly supplied by J. T. Park, Tufts University, Boston, Mass. Wiley. This strain (Wound) was kindly supplied by B. B. Wiley. When grown under certain conditions this strain has been reported to undergo a specific capsular reaction (23). Giorgio. This strain of S. aureus has been previously described (14) and is a prototypic non-ecapsulated S. aureus. All cultures were maintained on brain heart infusion agar (Difco) slants at 4 C. Unless otherwise noted, 18-h subcultures in brain heart infusion broth were used in all experiments.

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confidence: 99%

Biological Properties of the Encapsulated Staphylococcus aureus M

et al. 1974

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“…The use of polyvalent anticryptococcal serum would appear to be preferable to typing serum for routine diagnostic wroik although typing serum might find application in epidemiologic surveys. The antisera prepared by Neill and Kapros (1950) appear to exhibit more cross reaction than the typing sera prepared in this study. However, the data presented by these authors do not indicate the extent of cross reaction.…”

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confidence: 55%

The Antigenic Composition of Cryptococcus Neoformans V. A

1953

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“…A final aspect of our study may have bearing upon the consensus that heavily encapsulated cryptococci are less antigenic (i.e., stimulate lower antibody levels) than are cryptococci that are small capsuled or nonencapsulated or from which the capsule has been chemically removed (10,19). It has been our experience, as well as that of others (e.g., 12), that humans with cryptococcosis have polysaccharide rather than antibody in their serum, and that in human disease the organism usually is heavily encapsulated.…”

Section: Discussionmentioning

confidence: 99%

Pathogenesis, Lethality, and Immunizing Effect of Experimental Cutaneous Cryptococcosis

Dykstra

Friedman

1978

Infect Immun

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Mice were subcutaneously inoculated with small numbers of virulent Cryptococcus neoformans and divided into groups. Numbers of viable yeasts at the site were estimated at weekly intervals for 5 weeks on the basis of cultures of minced tissue excised from sacrificed animals. Organisms multiplied at the site for at least 4 weeks and were still detectable after the 5th week, although in reduced numbers. Agglutinins appeared within a week, but these antibodies were not detectable during the 2nd through the 5th week. Cryptococcal polysaccharide began to appear in the sera at 3 weeks, persisting through the duration of 5 weeks. All animals appeared healthy, but a few sickened after many months and died of systemic cryptococcosis. All of these events were observed in many separate experiments. The immunizing capacity of a cutaneous lesion was tested by challenging some of the above animals with viable C. neoformans after various intervals of time, either subcutaneously at a site distant from that of the vaccination or intravenously. Although we were unable to demonstrate reduced multiplication of yeasts in the brains, lungs, and spleens of intravenously challenged animals, it was possible to show that multiplication was inhibited at the site of subcutaneous challenge. It was noted also that vaccinated animals lived longer after lethal intravenous challenge than did nonvaccinated animals. The latter protection was observed, however, only when challenge followed vaccination by 3 weeks or longer, and it was effective only against a relatively low challenge dose. Mice were protected against a higher dose if they had previously received killed cryptococci, alternating subcutaneous and intraperitoneal inoculations, one of which contained a microbial adjuvant. No protection was observed in animals that were subcutaneously vaccinated with inert materials such as chitin, latex spheres, or even cryptococcal cell walls themselves.

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A Comparison of the Immunogenicity of Weakly Encapsulated and of Strongly Encapsulated Strains of Cryptococcus Neoformans (Torula Histolytica)

Cited by 47 publications

References 8 publications

Biological Properties of the Encapsulated Staphylococcus aureus M

Biological Properties of the Encapsulated Staphylococcus aureus M

The Antigenic Composition of Cryptococcus Neoformans V. A

Pathogenesis, Lethality, and Immunizing Effect of Experimental Cutaneous Cryptococcosis

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