RELATIONSHIP OF HOST ANTIBODY TO FLUCTUATIONS OFESCHERICHIA COLISEROTYPES IN THE HUMAN INTESTINE

Abstract

A study was undertaken to determine the relationship of host antibody to the changes which take place among Escherichia coli serotypes present in the intestine. A survey of six healthy persons examined for E. coli monthly for 6 months reaffirmed the periodic fluctuations of antigenic types. Serotypes were studied from each individual and their appearance and maintenance or disappearance closely followed. Representative strains were chosen each month and used to prepare a heated sodium hydroxide lipopolysaccharide extract for sensitizing human group 0 Rh-negative red blood cells for the hemagglutination test. These antigens were tested with the sera drawn from each of the six individuals at the time monthly cultures were made. Results showed that antibody levels for each serotype remained basically constant over the 6-month period. Titer levels tended to be characteristic of the host rather than related to the E. coli bacteria, as shown by tests with serotypes both from the individual's own intestinal tract and from other individuals in the study. High normal antibody levels for autologous E. coli serotypes did not act as a deterrent to the ability of the organisms to establish themselves in the bowel, nor did antibody titer for E. coli strains determine whether they would continue as residents over several months or depart as transient flora. Several studies over the past years have revealed that Escherichia coli serotvpes in the in-1 Thesis submitted in partial fulfillment of the requirements for Ph.D. degree at Catholic Uni

Naturally occurring antibodies in human sera that react with the iron-regulated outer membrane proteins of Escherichia coli

“…The immunoblot and the nitrocellulose paper carrying the '25I-labeled proteins were aligned exactly with the serrated edges before being placed on the X-ray film. a-hemolysin (4,7,15,19,20). It is also known that in humans, the level of these antibodies increases after E. coli infection.…”

Escherichia coli and Neonatal Disease of Calves

“…The production of colicines by strains of E. coli may be of some importance in maintaining them as resident strains (15), but, generally, this is not believed to be a major factor in the ability of a strain to establish itself as a resident (163,186,226). It was shown that host antibody to the E. coli strains involved plays no part in the phenomenon (61,163,175). Recently, an attempt was made to study this antagonism between certain strains of E. coli in vitro (220).…”

In vitro development of chlorhexidine resistance in Streptococcus sanguis and its transmissibility by genetic transformation

“…Antigenicaliy altered mutants are known to occur in bacterial infections (2,7,27) possibly as a result of the synthesis of antibody against certain surface antigens ofthe colonizing organisms (2). Antigenic, and other, properties, of bacterial cells may also change with varying environmental factors (32).…”