Naturally ocurring anti-GM1 antibodies: Campylobacter jejuni strains could act as immunogen

ALANIZ ME,; MOYANO AL,; COMIN R,; LARDONE RD,; NORES GA.

Rosario

Congreso; XLII Reunión Anual de la Sociedad Argentina de Investigaciones en Bioquímica y Biología Molecular (SAIB); 2006

  In contrast with the large body of evidence supporting a primary role of anti-GM1 antibodies in neuropathies, very little information is available about their origin. Based in studies on the antigen structural requirements for their binding it has been proposed that they originate from naturally occurring anti-GM1 antibodies. Anti-GM1 antibodies of the IgM isotype are part of the normal repertoire of human serum. They are absent in day-old babies and can be detected after few months. Their appearance shows a perfect concordance with well characterized anti-bacterial antibodies, an indication that they are part of the defence system toward these organisms. In the present study we develop a strategy to detect bacterium strains that could act as immunogen. Normal occurring anti-GM1 IgM-antibodies were purified from healthy human sera by GM1-affinity chromatography. This highly specific preparation was used to detect GM1-determinants in the lipopolisaccharides (LPS) fraction of several bacteria species. Positive reactions were only obtained with LPS from Campylobacter jejuni (four of  twenty strains). These results indicate that subclinic infection with certain strains of these bacterium could trigger the production of naturally occurring anti-GM1 antibodies.