title: Long-term feeding of the cis-9,trans-11 isomer of conjugated linoleic acid reinforces the specific immune response in rats.
abstract: Several effects on the immune system have been ascribed to the cis9,trans11 conjugated linoleic acid (CLA) isomer. We studied whether feeding a diet enriched with an 80:20 CLA isomer mix of cis9,trans11 and trans10,cis12 CLA from gestation to adulthood affects the capacity of adult rats to achieve a specific immune response. Pregnant Wistar rats were fed a 1% CLA diet or a control diet beginning on d 7 of gestation. Weaned pups received the same diet as dams until they were 15 wk old. Rats from both groups were immunized with ovalbumin (OVA) when they were 9 wk old. Dietary CLA enhanced splenocyte OVA-specific proliferation by approximately 50% (P < 0.05) and decreased the mitogen-induced proliferative responses of these cells by approximately 10-20% (P < 0.05). The diminished splenocyte proliferative response was accompanied by a lower interleukin-2 secretion (P < 0.05). Long-term CLA supplementation did not increase serum, spleen, or mesenteric lymph node production of OVA-specific antibodies (Ab) or the number of spleen anti-OVA Ab-secreting cells. Interestingly, dietary CLA increased intestinal anti-OVA IgA production by approximately 75% (P < 0.05). In conclusion, a 1% CLA diet administered from gestation to adulthood enhanced specific systemic cell-mediated immunity as well as the mucosal IgA immune response, whereas it downregulated the polyclonal activation of the immune system. These data support the long-term effects of dietary cis9,trans11 CLA isomer on the immune system.
authors.affiliation: Department of Physiology, Faculty of Pharmacy, University of Barcelona, Barcelona, Spain E-08028.
authors.forename: Carolina
authors.initials: C
authors.lastname: Ramírez-Santana
authors.forename: Cristina
authors.initials: C
authors.lastname: Castellote
authors.forename: Margarida
authors.initials: M
authors.lastname: Castell
authors.forename: Montserrat
authors.initials: M
authors.lastname: Rivero
authors.forename: Maria
authors.initials: M
authors.lastname: Rodríguez-Palmero
authors.forename: Angels
authors.initials: A
authors.lastname: Franch
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Pérez-Cano
mesh_terms: D000818:Animals; D004032:Diet; D005260:Female; D007111:Immunity, Cellular / Q000187:drug effects*; D007136:Immunoglobulins / Q000276:immunology*; D044243:Linoleic Acids, Conjugated / Q000494:pharmacology*; D010047:Ovalbumin / Q000276:immunology*; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000276:immunology; D015430:Weight Gain / Q000187:drug effects
chemical_list: D007136:Immunoglobulins; D044243:Linoleic Acids, Conjugated; D010047:Ovalbumin