1A-S1-2

EFFECTS OF RARs GENE EXPRESSION ON IMMUNE FUNCTIONS OF INFANTS WITH VITAMIN A DEFICIENCY

Wang WP, Zhang J and Yang Y

Children's Hospital of Fudan University, Shanghai, China

 

Objective: To study the mechanism of promotive effects of Vitamin A (VA) supplement on anti-infection immunity of young children.

Methods: The levels of serum vitamin A of 204 children aged 2~6 years in rural area were surveyed. 108 children whose serum vitamin A were lower than 0.70 mmol/L, received supplementation of VA in a period of 10 months. The levels of serum IgG and IgG subclasses, serum anti-pertussis antibody, sIgA of saliva, and the transcription level of retinoic acid receptor-a (RARa) gene were measured. The incidences of infectious diseases were recorded.

Results: A significant correlation was found between serum VA and the expression of RARa gene in lymphocytes of the children. Following up 108 children with serum vitamin A lower than 0.70 mmol/L, 85 of them the data are valid finally. According to the individual dynamic situation of serum VA at the end of the experiment, the children were divided into changed group (represents VA nutritional status rectified effectually) and unchanged group. Comparing with that of unchanged group, serum IgG3 concentration was reduced and the serum IgG4, anti-pertussis antibody, saliva sIgA was increased significantly (P<0.05) in the change group. In group of children aged 2~3 years old, the risk of diarrhea in the unchanged group was 3.33 times higher than that in the changed group (P<0.05).

Conclusion: The results indicated that the melioration of VA nutritional status on account of the supplementation improved the immune functions and ability against infection in young children with VA deficiency, which is related to the expression of RARa gene in lymphocytes. Present study provides the evidence that the VA nutritional status play an important role for natural expression of RARa gene that induces mainly functional activities of lymphocytes in young children.