[Autoantibodies to ganglioside GM3 and serotonin in blood serum in atherosclerosis].

Using ELISA method, the sera from 17 patients with atherosclerosis and 13 normal controls were examined for ganglioside- and serotonin-reactive antibodies. Gangliosides from human liver (GM31) and human aorta (GM3a) as well as GM2, GM1, GT1b, human brain cerebrosides and the BSA-serotonin conjugate (5-HT) were used as antigens. A group of patients showed statistically significant higher levels of anti-GM31 (82%) and anti-5-HT (71%) as compared to the control group. Taking into account the identical fatty acid composition of GM3 from human liver and platelets, one can assume that antibodies are produced against blood clot gangliosides in atherosclerotic patients' sera. This conclusion is supported by a high correlation (r = 0.06, p < 0.01) between the level of antibodies to 5-HT and GM31 in the sera of all patients. The sera of three patients with the highest content of antibodies to GM31 were shown to contain antibodies to GM3a and GT1b which were absent in control sera. No reaction with brain cerebrosides or GM1 and GM2 was detected in the sera of the examined persons. The differences in sera reactions with GM31 and GM3a can be explained as resulting from differences in the chain length of fatty acid residues of the ceramide moiety of gangliosides. The data obtained confirm the fact that antibodies to aorta gangliosides appear in the sera of atherosclerotic patients. Thus, the formation of atherosclerotic plaques leading to platelet activation, clot formation and ganglioside accumulation in aortic cells increase the levels of anti-ganglioside GM3 antibodies.