Hyperreactivity to endotoxin in mice infected with mycobacteria. Induction and elicitation of the reactions.

Abstract

In the mouse, the parenteral injection of whole mycobacteria, cord factor or mycobacterial cell walls induces a 100 to 500,000 fold decrease in the acute i/v LD(50) of endotoxic lipopolysaccharide (LPS) of Gram-negative organisms. Non-specific hyperreactivity of this kind is more easily induced by infection with living mycobacteria than by injection of dead organisms, and more easily when these are injected intravenously than intraperitoneally; but BCG and other strains of low virulence are as effective as fully virulent strains such as H(37)R(v) or Vallée. The hyperreactivity reaches a maximum at 7–9 days and persists for at least 3 weeks. All of four strains of mice tested behaved similarly.