Modulation of immune response by omega-3 in health and disease

Abstract

During the last 3-4 decades, there has been vast information on effect of omega-3 on the immune system in health and in diseases, especially those caused by excessive inflammatory response. In this chapter, attempts have been made to elucidate the effect of omega-3 on different components of immune system, especially during child development and in aged individuals. Omega-3 is also known to reduce the pathological manifestations especially in diseases related to inflammation, allergy and autoimmunity which are the major challenges today. Earlier studies on effect of polyunsaturated fatty acids in immune system were conducted using animal systems; in this chapter, more emphasis is given on human studies. n-3 PUFAs have been shown to be very effective in controlling inflammation by affecting extravasation, phagocytic response, generation of cytokines, inflammatory mediators and adhesion molecules. They also manipulate the functions of antigen-presenting cells and lymphocytes including T and B cells, NK cells, LAK cells and also T regulatory cells. Most of the reports on effect of dietary omega-3 in human health have been conducted as clinical trials, extrapolated from experiences in animals and also using in vitro techniques, which have limitations. The chapter reports trials conducted to assess the effectiveness of omega-3 diet supplementation in healthy volunteers using in vitro and in vivo assays. It also deals with the effect of omega-3 diet supplementation on pregnancy and lactation, especially in relation to infant allergies. Cognizance has also been taken of the effects of omega-3 diet supplementation in aged population. Finally, the chapter reviews important literature on the effectiveness of n-3 PUFAs in controlling inflammatory and autoimmune diseases such as rheumatoid arthritis, asthma, inflammatory bowel disease (IBD), psoriasis, cardiovascular disease, diabetes, multiple sclerosis and systemic lupus erythematosus (SLE).