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Vitamin A and immunity to viral, bacterial and protozoan infections

Published online by Cambridge University Press:  28 February 2007

R. D. Semba
R. D. Semba*
Affiliation:
Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
*
Corresponding Author: Dr R. D. Semba, fax +1 410 955 0629, email [email protected]
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Abstract

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Studies in animal models and cell lines show that vitamin A and related retinoids play a major role in immunity, including expression of mucins and keratins, lymphopoiesis, apoptosis, cytokine expression, production of antibody, and the function of neutrophils, natural killer cells, monocytes or macrophages, T lymphocytes and B lymphocytes. Recent clinical trials suggest that vitamin A supplementation reduces morbidity and mortality in different infectious diseases, such as measles, diarrhoeal disease, measles-related pneumonia, human immunodeficiency virus infection and malaria. Immune responses vary considerably during different infections, and the available data suggest that the modulation of immune function by vitamin A may also vary widely, depending on the type of infection and immune responses involved.

Keywords

Vitamin AImmunityInfectionMeaslesMalaria
Type
Symposium on ’Nutrition, infection and immunity‘
Information
Proceedings of the Nutrition Society , Volume 58 , Issue 3 , August 1999 , pp. 719 - 727
Copyright
Copyright © The Nutrition Society 1999

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