Evidence for a one-hit theory in the immune bactericidal reaction and demonstration of a multi-hit response for hemolysis by streptolysin O and Clostridium perfringens theta-toxin

Abstract

An analytical method was developed for estimating the number of hits necessary to lyse or kill cells in which various concentrations of the cells are treated with a constant amount of the lytic or killing agent in a constant reaction volume. The reaction may be due to a single-component agent or occur by a sequential chain of reactions due to a multi-component agent, even including side, abortive, or counter-reactions. It was clearly shown by this method that immune bactericidal reactions followed a one-hit theory. It was shown by this method that streptolysin 0 required four or five hits for hemolysis and Clostridium perfringens 0-toxin required two hits. These results were confirmed by both logarithmic dose-response and survival analyses. It was also shown that streptolysin 0 and 0-toxin can act complementarily on accumulation of the hits for hemolysis.

Neisseria gonorrhoeae acquire a new principal outer-membrane protein when transformed to resistance to serum bactericidal activity

“…Some traits, for example resistance to penicillin or loss of a growth requirement for uracil, have required up to 6 h for full phenotypic expression (14). Inoue et al (8) have presented evidence to show that the onehit theory of immune hemolysis could be extended to the immune bactericidal reaction. This could explain the unusually long time required for phenotypic expression.…”

The complement system: History, pathways, cascade and inhibitors

“…Mayer [17,18] proposed the 'one-hit' theory that suggested a single 'complement hit' could cause lysis of an erythrocyte. This was later supported by Inoue et al who showed that the complement could kill a bacterium by a single hit [19]. Using a reconstitution assay, Mayer and colleagues added partially purified components to antibody-sensitised sheep erythrocytes to unravel the reaction sequence of the classical pathway [20,21].…”

Bactericidal and bacteriolytic activity of serum against gram-negative bacteria.

“…The gram-negative cell obviously presents a more complex target for complement attack than the erythrocyte; bacteria have a more complex envelope structure, they can respond rapidly to changes in the environment, and they have a capacity for repair of damaged sites. Nevertheless, Inoue et al (128) developed an analytical method for determination of the number of lesions necessary for killing of E. coli B that involved exposure of increasing concentrations of antibody-sensitized bacteria to a constant amount of complement;…”