Energetic and nutritional regulation of immune response reviewed.

2004 NOV 3 - (NewsRx.com & NewsRx.net) -- Scientists review energetic and nutritional regulation of the adaptive immune response and trade-offs in ecological immunology in a recent issue of the American Journal of Human Biology.

"Ecological immunology views immunocompetence as a costly process involving trade-off decisions among competing nutrient demands by different life-history traits. This review examines immunocompetence fitness costs in light of recent work on the role the energetic and nutritional status of the host plays in the regulation of the adaptive T-helper lymphocyte response," researchers in the United States report.

"Three phenotypically distinct T-lymphocyte populations have been identified: the Th1 response, important in protecting against intracellular infections; the Th2 response, important in protecting against noninvasive infections such as helminthes; and the Th3 or Treg population, which down-regulates polarized Th1 or Th2 responses," stated Kurt Z. Long and Nanda Nanthakumar at Harvard University. "A strong Th1 response is protective against intracellular infections, while a Th2 response is protective against noninvasive infections."

"Adequate zinc and energy intake leads to a dominant Th1 response and a downregulated Th2 response, while deficiencies of either of these results in activation of the Th2 response and downregulation of the Th1 response," reported Long and Nanthakumar. "In contrast, adequate vitamin A intake leads to an ...