RESUMEN
The impact of vitamin A supplementation on childhood diarrhea may be determined by the regulatory effect supplementation has on the mucosal immune response in the gut. Previous studies have not addressed the impact of vitamin A supplementation on the production of monocyte chemoattractant protein 1 (MCP-1), an essential chemokine involved in pathogen-specific mucosal immune response. Fecal MCP-1 concentrations, determined by an enzyme-linked immuno absorption assay, were compared among 127 Mexican children 5-15 mo of age randomized to receive a vitamin A supplement (<12 mo of age, 20,000 IU of retinol; > or =12 mo, 45,000 iu) every 2 mo or a placebo as part of a larger vitamin A supplementation trial. Stools collected during the summer months were screened for MCP-1 and gastrointestinal pathogens. Values of MCP-1 were categorized into 3 levels (nondetectable,
Asunto(s)
Quimiocina CCL2/análisis , Quimiocina CCL2/inmunología , Diarrea/inmunología , Intestinos/inmunología , Vitamina A/administración & dosificación , Animales , Antiinflamatorios/administración & dosificación , Ascariasis/inmunología , Ascaris lumbricoides , Quimiocina CCL2/biosíntesis , Diarrea/microbiología , Diarrea/parasitología , Suplementos Dietéticos , Ensayo de Inmunoadsorción Enzimática , Infecciones por Escherichia coli/inmunología , Heces/química , Heces/microbiología , Heces/parasitología , Giardia lamblia , Giardiasis/inmunología , Humanos , Lactante , Intestinos/química , Modelos Logísticos , México , PlacebosRESUMEN
Vitamin A supplementation has consistently reduced infant mortality and the severity of pathogen-induced diarrhea. The mechanism by which vitamin A modulates the mucosal immune response to produce these effects remains poorly defined. To address this issue, stools collected during the summer months from 127 Mexican children 5-15 mo old enrolled in a larger, randomized, double-blind, placebo-controlled, vitamin A supplementation trial were screened for interleukin (IL)-4, IL-6, interferon-gamma (IFN-gamma), and gastrointestinal pathogens. Fecal cytokine values were categorized into 3 levels (undetectable,