UNSATURATED FATTY-ACIDS DECREASE IN-VITRO PROLIFERATION AND CD4-LYMPHOCYTES( EXPRESSION IN HUMAN)

The aim of this study was to evaluate in vitro the effect of fatty aci ds at different concentrations on the immunologic activity of human T and B lymphocytes. Peripheral blood mononuclear cells (PBMC) were isol ated from healthy blood donors, and activated by adding phytohemagglut inin (PHA), The cultures were supplemented with the following free fat ty acids: oleic acid (100 mu M, 200 mu M and 375 mu M), linoleic acid (100 mu M, 200 mu M and 375 mu M) and palmitic acid (100 mu M, 200 mu M and 375 mu M). The cultured lymphocytes not supplemented with free f atty acids were used as controls, After 48-hr in culture the PBMC were analyzed: cell surface marker analysis by flow cytometry (CD19, CD3, CD?, CD8 and CD16) and 14 lymphocyte proliferation was estimated by [N -3] thymidine incorporation. At concentration of 200 mu M there was a lower proliferation with all fatty acids evaluated, When the concentra tion was increased to 375 mu M the differences became more evident, sh owing a proliferative decrease for oleic acid (6.1% of the control) (p <0.01), linoleic acid (5%) (p<0.01) and palmitic acid (32%) (p<0.05) c ompared to the control values, For this same concentration a significa nt decrease (p<0.001) in the lymphocyte expression of CD3+ and CD4+ wa s observed in the oleic and linoleic acid cultures, The decrease in CD 3+ expression as linoleic and oleic acid was added to the cultures was caused by a decrease in CD4+ as the CD8+ expression remained unchange d, Vitamin E failed to revert the effect of the fatty acids on lymphoc yte proliferation or the change in expression of the surface markers, Levels of fatty acids higher than 350 mu M occur in certain clinical s ettings, so the possible effect of inmunomodulation should be evaluate d. (C) 1997, Editrice Kurtis.