Tissue-Culture Assay of Antibodies to Heat-LabileEscherichia coliEnterotoxins

Abstract

Serums of volunteers challenged orally with either toxigenic or invasive strains of Escherichia coli were analyzed for antibody content by means of an adrenal tumor-cell tissue-culture system and by the standard rabbit ileal-loop method. The tissue-culture assay system depends on the ability of specific antibody to neutralize the morphogenic effects of heat-labile Esch. coli enterotoxins. Six of seven volunteers receiving the toxigenic strains demonstrated fourfold or greater increases in antibody titers to heat-labile Esch. coli enterotoxins by the tissue-culture method, whereas eight of nine receiving the invasive Esch. coli strains did not demonstrate any such increases. These results compared favorably with those obtained by the ileal-loop method.