Studies on anti-H reagents.

Anti-H from nine people, eight Oh and one A1 (Toml.), as well as monoclonal anti-Type 2 H (H11), anti-HI from an OHm person and the anti-H lectins from Ulex europaeus seeds, Lotus tetragonolobus seeds and eel serum were all analysed by adsorption tests using Synsorb immunoadsorbents, by inhibition tests with various oligosaccharides and body fluids and by titration tests with red cells from cord and adult samples. The adsorption tests showed that all of the reagents bound preferentially to the Type 2 H trisaccharide although only the monoclonal antibody and the serum from Toml. bound exclusively to Type 2 H. All of the Oh sera were inhibited by saliva, by H glycoprotein from ovarian cyst fluid and meconium, and by 2'-fucosyllactose but none was inhibited by lacto-difucotetraose or by lacto-N-fucopentaose I. H11 and Toml. serum again showed similar specificity in inhibition tests with milk oligosaccharides but whereas H11 is not inhibited by saliva or ovarian cyst fluid Toml. serum is. Only the three lectins were inhibited by alpha-L-fucose. Some of the Bombay sera gave similar titration scores with both cord and adult red cells whereas others gave much lower scores with cord cells than with adult cells. H11 and Toml. serum behaved like those of the former category whereas the anti-HI and the lectins behaved like the latter.