Natural IgM and IgG antibodies to Thomsen-Friedenreich (T) antigen in serum of patients with gastric cancer and blood donors--relation to Lewis (a,b) histo-blood group phenotype.

A possible association of serum anti-T IgM and IgG antibody levels with Lewis blood-group phenotype was investigated in 168 blood donors and 132 gastric cancer patients using ELISA with synthetic T-disaccharide-polyacrylamide conjugate as antigen. The donors of Le(a-b+) phenotype showed the highest anti-T IgM level irrespective of ABO(H) blood group. A significant decrease in anti-T IgM in serum was observed among cancer patients of Le(a-b+) phenotype: 95% of weak responders versus 17.

IgG antibodies to Lewis type 2 antigens in serum of H. pylori-infected and noninfected blood donors of different Lewis(a,b) blood-group phenotype.

Individuals of the Le(b+)/secretor phenotype revealed a stronger natural immune response to Le(x) and Le(y) epitopes irrespective of Helicobacter pylori serologic status. In contrast, H. pylori-infected Le(b-) type individuals showed a significantly higher proportion of strong responders to Le(x) antigen compared with the H.

The Helicobacter pylori seroprevalence in blood donors related to Lewis (a,b) histo-blood group phenotype.

Objective: To study a possible association of the Helicobacter pylori seroprevalence with ABO(H) and Lewis (a,b) blood group phenotypes in blood donors.

Design: A cross-sectional study of blood donors using ABO(H) and Lewis (a,b) blood group phenotype as predictors.

Methods: ABO(H) and Lewis (a,b) blood group phenotyping was performed with monoclonal antibody.

[The induction and disappearance of complement-fixing antibodies in the blood serum of experimental animals under the antigenic action of Trichomonas vaginalis, T. hominis and T. tenax].

For studying the dynamics of induction and disappearing of complement-fixing antibodies (CFA) specific to Trichomonas vaginalis, T. hominis and T. tenax we have immunized rabbits intravenously with live individuals of the protozoa as well as intravenously, intramuscularly and subcutaneously with individuals killed at 56 degrees C.