Production and characterization of monoclonal antibodies to a Veillonella species from a continuous-flow culture system of chicken cecal bacteria

Administering native intestinal flora to newly hatched chicks protects against cecal Salmonella colonization, and is known as competitive exclusion. Continuous-flow culture systems have been used to maintain defined competitive exclusion cultures. We have recently demonstrated that such a stable continuous-flow culture, CF3, contains 29 bacterial strains representing ten genera. Broiler chicks treated with CF3 are protected against Salmonella colonization of the ceca. Such protection is correlated with elevated concentrations of proprionic acid in the cecal contents of treated chicks. In this study we report on the preparation and characterization of monoclonal antibodies to one of the proprionic acid producing anaerobes contained in CF3, namely Veillonella CF3. Five different monoclonal antibodies were characterized with respect to: (1) isotype; (2)Veillonella specificity as judged by cross-reactivity profiles with other bacteria; (3) sensitivity as measured by the limit of detection of the number of colony forming units of Veillonella; and (4) antigen recognition of Veillonella by Western Blot analysis. These antibodies have been used to enumerate Veillonella in both the CF3 cultures and in the ceca of young chicks.