Variation of blood group antigen expression on vaginal cells and mucus in secretor and nonsecretor women

The expression of blood group antigens on the surface of urothelial cells and in mucus is controlled partly by the blood type and secretor status of the individual. To our knowledge, the possibility that the levels of these antigens vary with time has not been previously assessed. We determine if the pattern and/or intensity of blood group antigen expression on vaginal epithelial cells and mucus changed with time. Cell and mucus specimens were collected weekly for 3 months from 10 women: 5 (2 secretors and 3 nonsecretors) with and 5 (3 secretors and 2 nonsecretors) without a history of urinary tract infections. In addition, samples were collected on 5 consecutive days from 5 of these individuals. The cell and mucus samples were assayed for ABH and Lewis blood group antigens using monoclonal antibodies in cell concentration immunofluorescence and enzyme-linked fluorogenic assays, respectively. Although the pattern of antigen expression in the vaginal cell and mucus samples was consistent with the blood type and secretor status of an individual, in all women the level of antigen expression changed significantly and rapidly during the 3-month and 5-day periods. The results show a previously unrecognized phenomenon and demonstrate that the expression of blood group antigens on vaginal cells and in mucus is a dynamic process.