Inhibition by Lecithin and Cholesterol of Bacterial (Escherichia Coli) Hemagglutination and Hemolysis

[摘要] The effects of lecithin and cholesterol on Escherichia coli O26 hemagglutination and hemolysis were studied and the following results obtained.1. (1) Both crude and purified lecithin preparations, after contact with the bacterial antigen, inhibited E. coli hemagglutination. As little as 0.5 mg (0.1 mg per ml) of the purified preparation E prevented this reaction completely. This preparation also inhibited E. coli hemolysis.2. (2) Cholesterol in amount of 0.05 mg, after contact with the bacterial antigen, inhibited E. coli hemagglutination and 0.5 mg prevented hemolysis.3. (3) The inhibitory effect of both lecithin and cholesterol depends, aside from their concentration, upon the amount of bacterial antigen used, the length of time of contact between inhibitor and antigen and the temperature at which the mixtures were kept.4. (4) Purified lecithin preparation E and cholesterol, when allowed to act on red blood cells, did not inhibit hemagglutination, indicating that their major effect is upon the antigen.5. (5) Red blood cells treated with inhibitor-antigen mixtures failed to adsorb homologous bacterial antibodies of human origin, as evidenced by failure to be agglutinated by anti-human globulin (rabbit) antiserum; the latter serum caused agglutination of erythrocytes which had been modified by antigen alone and then treated with the same bacterial antiserum.6. (6) Cholesterol-antigen mixture was precipitated at least as well as the untreated antigen by homologous E. coli antiserum and lecithin-antigen mixtures but slightly less than the control antigen, indicating that the inhibitory effects of the lipids on E. coli hemagglutination is not due to destruction of the bacterial antigen.7. (7) The phenomena of bacterial ( Escherichia coli ) hemagglutination and hemolysis and their inhibition by lecithin and cholesterol are discussed.

[学科分类] 生物科学（综合）