[Antigenic cross-reaction between neonatal intestinal mucosa and certain serotypes of Escherichia coli]

In the soluble and insoluble fractions of three intestinal mucosa of neonates, a study was made of the contents of Kunin's (ECA) common heterogenous antigen, and of somatic antigens of different E. coli serotypes. In the three mucosas, evidence was found that a fraction capable of hindering the antiserum anti-014, (antiserum anti-ECA), does exist. It was also discovered that the three mucosas have a variable content of substances which hinder antiserums contrary to different somatic antigens of various E coli's serotypes. Furthermore, the soluble and insoluble fractions of the intestinal mucosas "combine' when they are preincubated with some of the crude lipopolysaccharides (LPS) of E. coli enteropathogens and non-enteropathogenes, according to the determining antigens be they divided into equal parts or not. This last phenomenon modifies, in variable degrees, the capacity of these fractions to hinder the antiserums contrary to the determinative equal parts with E. coli. Based on the above observations, the author proposes a hypothesis in order to explain the different behaviour, (pathogen and/or commensal), of a similar E. coli's serotype when it settles in the intestine of different people