Vitamin A, a naturally occuring antioxidant micronutrient, has immunomodulating effect in patients with immunodeficiency, including an influence on cytokine production and lymphocyte growth and functions. Vitamin A deficiency is associated with a shift from type 2 cytokines to predominantly type 1 cytokines. The aims of this study were to determine Vitamin A status in Common variable immunodeficiency (CVID) patients and the relationship between Vitamin A status and cytokines production. Serum Vitamin A, neopterin, TNF-alpha, IL-2, IL-4, and IL-10 levels were determined in 19 CVID patients and 15 healthy children. Effects of 9-cis retinal, Vitamin A derivative, on cytokines (TNF-alpha, IL-2, IL-4 and IL-10) production in lymphocytes were tested in vitro condition using lymphocyte cultures obtained from CVID patients and healthy children.
Serum Vitamin A level in CVDI patients was, 21.1± 1.5 μg/dL, significantly (p < 0.001) lower than the value, 35.7± 1.8 μg/dL, observed in healthy children. Serum neopterin level in the patients was, 9.8± 2.9 nmol/L, higher (p < 0.05) than the value, 3.9± 0.7 nmol/L, observed in control group. Common variable immunodeficiency patients, serum IL-4 level was significantly (p < 0.05) lower than the value observed for healthy children. Serum TNF-alpha, IL-2 and IL-10 levels were similar in the patients and healthy children. Vitamin A derivative, 9-cis retinal, increased TNF-alpha and IL-4 production in cultured mononuclear cells obtained from control and CVID patients. Vitamin A derivative, also, increased IL-2 and Il-4 production in cultured mononuclear cells obtained from CVID patients.
These results show that CVID patients have low serum Vitamin A levels and high serum neopterin levels. A supplementation with Vitamin A may have role in downregulation of inflammatory responses in CVID patients.