Phospholipid methylation of the membrane of neutrophils and lymphocytes in various inflammatory diseases

Abstract

Recently, there have been critics that assessment of phospholipid methylation of microsomal fractions does not necessarily represent membrane fluidity of dynamics. With our improved method, the author assessed the methylation of membrane in neutrophils and lymphocytes from the patients with various diseases including Behcet's disease and systemic lupus erythematosus (SLE) . The methyl assay was also performed with stimulation of opsonized zymosan (0.2 mg/ml) and Con A (2μg/ml) . Overall, [3H] -methyl incorporated to microsomal fractions in lymphocytes is greater than in neutrophils. Methylation of both neutrophils (P<0.001) and lymphocytes (P<0.01) in the patients with active Behcet's disease was most highly enhanced among all the diseases tested. The patients with active rheumatoid arthritis (RA), severe bacterial diseases and mucocutano lymphnode syndrome (within 7 days after its onset) also showed an increase in [3H] -methyl incorporated. The increase in methylation in the patients paralleled to their disease activity. In active SLE patients, methylation was not so highly increased and lymphocyte methylation showed no significant enhancement, compared to healthy controls. No increase in methylation was observed in patients with severe viral diseases. The present study seems to indicate that our original assay of phospholipid methylation of the membrane of neutrophils and lymphocytes is appraisable indicator of inflammation.