ct of vitamin D deficiency on immune T cells in asthmatic children: a case-control study Original Research (4185) Total Article Views Authors: Maalmi H, Berra es A, Tangour E, Ammar J, Abid H, Hamzaoui K, Hamzaoui A Published Date May 2012 Volume 2012:5 Pages 11 - 19 DOI: http://dx.doi.org/10.2147/JAA.S29566 Received: 29 December 2011 Accepted: 14 February 2012 Published: 09 May 2012 Ha fa Maalmi,1,2 Anissa Berra es,1,2,3 Eya Tangour,1,2,3 Jamel Ammar,1,2,3 Hanadi Abid,1,2,3 Kamel Hamzaoui,1,2 Agnes Hamzaoui1,2,3 1Department of Basic Sciences, Medicine School of Tunis, University Tunis El Manar, Tunis; 2Unit Research, Homeostasis and Cell Dysfunction, Ariana; 3Department of Pneumopediatry, A Mami Hospital, Ariana, Tunisia Background: Vitamin D exerts profound effects on both adaptive and innate immune functions involved in the development and course of autoimmune and inflammatory diseases. As the incidence of vitamin D insufficiency is surprisingly high in the general population, experimental studies have started to investigate whether vitamin D levels (measured as serum 25 hydroxy vitamin D-25[OH]D) are correlated with immune cells and clinical parameters. Purpose: The aim of the present research was to investigate serum vitamin D status in a case-control study in children with asthma and to study associations between vitamin D levels and certain immunological parameters. Materials and methods: A case control study of thirty-nine children with clinically controlled asthma was enrolled to assess the relationship between serum vitamin D concentrations and disease activity. Vitamin D was assayed with a radioimmunoassay kit. We evaluated the relationship between vitamin D concentrations and forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and the FEV1/FVC ratio. Correlations between inflammatory mediators, Th1, Th2, Th17, and regulatory T cells (Treg) and vitamin D were investigated. Results: Only 15.38% of our asthmatic children had a sufficient serum 25(OH)D (≥30 ng/mL) whereas 80% of healthy children expressed sufficient levels. Deficient values of vitamin D (<20 ng/mL) were observed in 17 (43.59%) asthmatic patients (14.40 ± 3.30 ng/mL; P = 0.0001). Deficiency was not observed in controls. Th1/Th2 ratio was significantly correlated to 25(OH)D level (r = 0.698; P = 0.0001). A significant negative correlation was observed between serum interleukin-17 and vitamin D levels in young asthmatics (r = -0.617; P = 0.001). A significant correlation was observed between CD25+Foxp3+ Treg cells and vitamin D values in asthmatics (r = 0.368; P = 0.021). Conclusion: Even in a southern Mediterranean country, hypovitaminosis D is frequent in children with asthma. Our findings suggest that vitamin D is an important promoter of T cell regulation in vivo in young asthmatics.