Vitamin A deficiency results in a priming environment conducive for Th1 cell development

Eur J Immunol. 1995 Jun;25(6):1673-9. doi: 10.1002/eji.1830250629.

Abstract

Certain infections, like that with the human immunodeficiency virus-1, deplete vitamin A, and when vitamin A levels are low, immune dysfunctions establish susceptibility to further infection. Our research has focused on the immune dysfunctions that are a consequence of vitamin A deficiency and that predispose to further infection. We previously studied a helminth infection in mice, and showed that when vitamin A levels are low, the immune response develops a strong regulatory T cell imbalance with excessive T helper type-1 cell interferon (IFN)-gamma synthesis and insufficient T helper type-2 cell development and function. Here, we studied the T cell priming environment in vitamin A-deficient mice to learn how that priming environment might produce a regulatory T cell imbalance and consequently distort the ability of the immune system to respond to an infection. Our results show that during vitamin A deficiency, the priming environment included constitutive interleukin (IL)-12 and IFN-gamma transcripts, but it was devoid of constitutive IL-4 and IL-10 transcripts. Dietary all-trans-retinoic acid supplementation down-regulated the level of constitutive IL-12 and IFN-gamma transcripts. Furthermore, when T cells from naive vitamin A-deficient animals were stimulated through the T cell receptor, they produced excess IFN-gamma protein compared to T cells from control animals. In contrast, T cell stimulation failed to induce IL-4 or IL-10 secretion. The inducible IFN-gamma was largely from CD8+ T cells and all-trans-retinoic acid addition in vitro inhibited IFN-gamma production at the transcript level. Retinoic acid addition in vitro also decreased natural killer cell IFN-gamma synthesis at the transcript level. Taken together, the distorted constitutive and inducible cytokine gene expression patterns that occurred when vitamin A levels were low would be expected strongly to favor T helper type-1 development and limit T helper type-2 cell growth and differentiation, thereby limiting the animal's humoral immune response capability.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cell Differentiation
  • Cells, Cultured
  • Diet
  • Down-Regulation
  • Interferon-gamma / antagonists & inhibitors
  • Interferon-gamma / biosynthesis*
  • Interleukin-12 / antagonists & inhibitors
  • Interleukin-12 / biosynthesis*
  • Mice
  • T-Lymphocytes, Helper-Inducer / immunology*
  • Transcription, Genetic
  • Tretinoin / administration & dosage*
  • Vitamin A Deficiency / immunology*

Substances

  • Interleukin-12
  • Tretinoin
  • Interferon-gamma