The triggering signal dictates the effect of docosahexaenoic acid on lymphocyte function in vitro.
Docosahexaenoic acid (DHA) is an n-3 fatty acid beneficial to several human conditions including inflammation and autoimmune disease. To better understand the effect of DHA on immunity, we monitored the rise in cytosolic free calcium, interleukin 2 receptor (IL2R) expression, and proliferation of splenic lymphocytes triggered with three different stimuli in the presence or absence of DHA. We found that 10 microg DHA/mL suppressed concanavalin A-induced mitogenesis and the mixed lymphocyte reaction while concurrently enhancing proliferation stimulated with anti-Thy-1 antibodies. Proliferation, as measured by [3H]thymidine incorporation after 2 to 5 d of culture, was affected by DHA, but earlier activation effects such as elevation of cytosolic free calcium and IL2R expression were not altered. These results imply that DHA incorporated into membrane phospholipids differentially affects the activity of distinct membrane-bound receptors and signaling molecules. This result suggests that DHA may be used to modulate immune responses selectively, e.g., to suppress undesired autoimmunity while maintaining protective immunity.
Jenski
L J
LJ
Department of Biology, Indiana University-Purdue University at Indianapolis 46202-5132, USA. LJENSKI@IUPUI.EDU
Scherer
J M
JM
Caldwell
L D
LD
Ney
V A
VA
Stillwell
W
W
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D003208:Concanavalin A / Q000494:pharmacology; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D007518:Isoantibodies / Q000494:pharmacology*; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008934:Mitogens / Q000494:pharmacology; D015375:Receptors, Interleukin-2 / Q000187:drug effects / Q000378:metabolism*
D007518:Isoantibodies; D008934:Mitogens; D015375:Receptors, Interleukin-2; C035678:anti-Thy antibody; D003208:Concanavalin A; D004281:Docosahexaenoic Acids; D002118:Calcium