INDUCTION OF NONSPECIFIC RESISTANCE BY ENDOTOXIN IN UNRESPONSIVE MICE

Area of Science:

• Immunology
• Microbiology
• Bacteriology

Background:

• Endotoxins are known to induce resistance against various pathogens.
• Immunological paralysis can be induced in animals, rendering them unresponsive to specific antigens.

Purpose of the Study:

• To investigate the role of immunological competence in endotoxin-induced resistance.
• To determine if immunological paralysis affects the efficacy of endotoxin in conferring resistance.

Main Methods:

• Serratia marcescens endotoxin was administered to mice with varying levels of immunological competence.
• Mice were challenged with Diplococcus pneumoniae to assess resistance.
• Immunologically paralyzed mice were used to evaluate the influence of unresponsiveness on endotoxin efficacy.

Main Results:

• Endotoxin conferred resistance to Diplococcus pneumoniae challenge in normal mice.
• The same dose of endotoxin was equally effective in inducing resistance in immunologically paralyzed mice.
• The degree of resistance induced by endotoxin was not influenced by the unresponsive state.

Conclusions:

• Nonspecific resistance induced by endotoxin is effective even in immunologically unresponsive states.
• Specific humoral factors likely do not play a significant role in mediating endotoxin-induced nonspecific resistance.