Enzyme-linked immunosorbent assays for detection of thermostable direct hemolysin of Vibrio parahaemolyticus

Abstract

Several systems for enzyme-linked immunosorbent assay (ELISA) of thermostable direct hemolysin (TDH) of Vibrio parahaemolyticus were tested, and single-antibody sandwich ELISA systems gave satisfactory results. ELISA was able to detect as little as several nanograms of purified TDH per milliliter. The method of De Jong (J. Clin. Microbiol. 17:928-930, 1983) and the glutaraldehyde method were successful for preparing conjugates of alkaline phosphatase and anti-TDH antibody. TDH in fluids in intestinal loops of experimental animals challenged with living V. parahaemolyticus was accurately detectable by ELISA.