CD11c(+) dendritic cells maintain antigen processing, presentation capabilities, and CD4(+) T-cell priming efficacy under hypercholesterolemic conditions associated with atherosclerosis.

Autor: Packard RR; Leducq Center for Cardiovascular Research and Donald W Reynolds Cardiovascular Clinical Research Center, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA., Maganto-García E, Gotsman I, Tabas I, Libby P, Lichtman AH
Jazyk: angličtina
Zdroj: Circulation research [Circ Res] 2008 Oct 24; Vol. 103 (9), pp. 965-73. Date of Electronic Publication: 2008 Oct 02.
DOI: 10.1161/CIRCRESAHA.108.185793
Abstrakt: Recent reports suggest dyslipidemia impairs dendritic cell (DC) function and adaptive immunity. This study aimed to characterize the effect of hypercholesterolemia on antigen-presenting cell function of DCs and DC-dependent CD4(+) T-cell responses. DCs incubated in vitro with acetylated low-density lipoprotein cholesterol with or without an acyl-coenzyme A:cholesterol acyl-transferase inhibitor maintained their ability to prime CD4(+) T cells. Analysis of T-cell proliferation and interferon-gamma and tumor necrosis factor-alpha production after ex vivo coculture of naïve CD4(+) T cells with splenic, inguinal, or iliac DCs from low-density lipoprotein receptor-deficient (LDLR(-/-)) or apolipoprotein E-deficient (ApoE(-/-)) mice fed an atherogenic diet highlighted DC efficacy in effector T-cell generation under hypercholesterolemic conditions. Adoptive transfer of carboxyfluorescein diacetate, succinimidyl ester (CFSE)-labeled naïve CD4(+) T cells in LDLR(-/-) recipients and subsequent immunization demonstrated effective priming of naïve T cells in hypercholesterolemic mice. CFSE dilution analyses revealed that hypercholesterolemic DCs were equipotent in naïve CD4(+) T-cell priming efficacy with normocholesterolemic DCs. Quantitative real-time PCR and flow cytometric analyses demonstrated that DC expression of multiple molecules involved in antigen processing, presentation, and T-cell stimulation remained unaltered by dyslipidemia. Finally, endogenous antigen-primed CD4(+) T cells responded equivalently to a secondary ex vivo antigenic challenge, regardless of whether they were primed in vivo under hypercholesterolemic or control conditions, demonstrating that all essential steps in CD4(+) T-cell responses remain intact under atherogenic conditions. This study affirms that the adaptive immune response prevails under the hypercholesterolemic conditions present in atherosclerosis. In particular, DCs remain functional antigen-presenting cells and maintain their ability to prime CD4(+) T cells even when cholesterol-loaded.
Databáze: MEDLINE