Retinoic Acid as a Modulator of T Cell Immunity.
Vitamin A, a generic designation for an array of organic molecules that includes retinal, retinol and retinoic acid, is an essential nutrient needed in a wide array of aspects including the proper functioning of the visual system, maintenance of cell function and differentiation, epithelial surface integrity, erythrocyte production, reproduction, and normal immune function. Vitamin A deficiency is one of the most common micronutrient deficiencies worldwide and is associated with defects in adaptive immunity. Reports from epidemiological studies, clinical trials and experimental studies have clearly demonstrated that vitamin A plays a central role in immunity and that its deficiency is the cause of broad immune alterations including decreased humoral and cellular responses, inadequate immune regulation, weak response to vaccines and poor lymphoid organ development. In this review, we will examine the role of vitamin A in immunity and focus on several aspects of T cell biology such as T helper cell differentiation, function and homing, as well as lymphoid organ development. Further, we will provide an overview of the effects of vitamin A deficiency in the adaptive immune responses and how retinoic acid, through its effect on T cells can fine-tune the balance between tolerance and immunity.
Departamento de Biologia, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, &#209;u&#241;oa, Santiago 7800003, Chile. mrbono@uchile.cl.
Maria Rosa
MR
Bono
Departamento de Biologia, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, &#209;u&#241;oa, Santiago 7800003, Chile. Gabrielatejon@gmail.com.
Gabriela
G
Tejon
Departamento de Biologia, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, &#209;u&#241;oa, Santiago 7800003, Chile. felipeflores.uchile@gmail.com.
Felipe
F
Flores-Santibañez
Departamento de Biologia, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, &#209;u&#241;oa, Santiago 7800003, Chile. dominique.fernandez.q@gmail.com.
Dominique
D
Fernandez
Departamento de Biologia, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, &#209;u&#241;oa, Santiago 7800003, Chile. mrosemblatt@cienciavida.org.|Fundacion Ciencia &amp; Vida, Santiago 7780272, Chile. mrosemblatt@cienciavida.org.|Facultad de Ciencias Biologicas, Universidad Andres Bello, Santiago 8370146, Chile. mrosemblatt@cienciavida.org.
Mario
M
Rosemblatt
Departamento de Biologia, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, &#209;u&#241;oa, Santiago 7800003, Chile. dsauma@u.uchile.cl.
Daniela
D
Sauma
D056704:Adaptive Immunity; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002986:Clinical Trials as Topic; D019587:Dietary Supplements; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000187:drug effects; D006801:Humans; D007108:Immune Tolerance; D007111:Immunity, Cellular; D008214:Lymphocytes / Q000187:drug effects; D038081:Organogenesis; D013601:T-Lymphocytes / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D058504:Th17 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D013950:Thymus Gland / Q000187:drug effects; D014212:Tretinoin / Q000502:physiology*; D014802:Vitamin A Deficiency / Q000097:blood / Q000188:drug therapy
D014212:Tretinoin
T cell; homing; oral tolerance; retinoic acid; vitamin A