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THE PRODUCTION OF PURPURA BY DERIVATIVES OF PNEUMOCOCCUS : III. FURTHER STUDIES ON THE NATURE OF THE

L A Julianelle1, H A Reimann

  • 1Hospital of The Rockefeller Institute for Medical Research.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

The Pneumococcus purpura-producing substance is non-antigenic and not preformed in cells. Repeated toxic doses increase resistance in mice, but immune serum offers no protection.

Area of Science:

  • Microbiology
  • Immunology
  • Pathogenesis

Background:

  • Pneumococcus infections can lead to various complications.
  • The specific mechanisms underlying purpura induction by Pneumococcus are not fully understood.

Purpose of the Study:

  • To investigate the nature of the purpura-producing principle of Pneumococcus.
  • To determine if this principle is antigenic and its origin within the bacterial cell.

Main Methods:

  • Toxic doses of the purpura substance were injected into white mice.
  • Rabbits were immunized with Pneumococcus components, and their serum was tested for protective effects.
  • Pneumococcal extracts were analyzed to identify the fraction associated with the purpura substance.

Main Results:

  • The purpura-producing principle was found to be non-antigenic, failing to stimulate antibody formation.
  • Repeated exposure to toxic doses of the substance enhanced resistance in mice.
  • Immune sera from rabbits did not protect mice against purpura.
  • The principle is an autolytic derivative, formed during bacterial autolysis, not pre-existing in the cell.
  • The substance is associated with the proteose fraction of pneumococcal extracts.

Conclusions:

  • The purpura-producing principle of Pneumococcus is a non-antigenic autolytic derivative.
  • Understanding its origin and properties is crucial for comprehending Pneumococcus pathogenesis.
  • Further research may explore therapeutic strategies targeting this substance.

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