Inhibition of complement-dependent rosette formation after lymphocyte incubation with fatty acids.

Overnight incubation of lymphocytes with certain fatty acids bound to albumin has previously been shown to modify the fatty acid composition of cellular phosphoglycerides without impairing viability, and also to inhibit mitogen and antigen-induced lymphocyte transformation. In the present study, incubation of human lymphocytes with palmitic acid or with linoleic acid impaired their capacity to form complement-dependent rosettes but had no effect on either spontaneous rosette formation with sheep erythrocytes or Fc(gamma)-dependent rosette formation. With mouse lymphocytes, complement-dependent rosette formation was suppressed only following incubation with linoleic acid and there was no effect on Fc(gamma)-dependent rosette formation. Although the mechanism of these effects remains to be elucidated the results suggest that control of membrane lipid composition may modify the important in vivo immunological functions which involve complement receptors.