The influence of selenium supplementation on the immunity of corticoid-dependent asthmatics

Selenium (Se) is a trace element that is essential for immune functions, and protects the immune system from oxidative damage.

The aim of the pilot clinical study was to assess the influence of selenium supplementation (SeS) on the selected immune parameters analyzed from peripheral blood of corticoid-dependent asthmatics (CDAs).

Seventeen CDAs aged from 30 to 74 years (7 females, 10 males) with suboptimal levels of Se in plasma were enrolled into the study. The follow up of SeS lasted 96 weeks. It is daily dose was 200 micrograms (2 x 2 tbl daily, 1 tbl contained 50 micrograms of Se). Before (-4 weeks) and after the 12th, 48th, 72nd and 96th weeks of SeS, the following parameters were observed: Epitopes EG1, EG2 expressed on intracellular eosinophil (Eo) cationic protein and eosinophil peroxidase, the numbers of CD3, CD4, CD8, CD19 and CD3 HLADR positive T lymphocytes (Ly), lymphocyte blastogenesis test (LTT) with mitogens concanavalin A, (Conc A) phytohemaglutin (PHA), the levels of C3, C4 complement components, activation of complement by classic and alternative pathways (CP50, AP50), the levels of immunoglobulins (Ig) G, A, M and total IgE, circulating immune complexes (CIC).

Epitopes EG1 and EG2 in cytoplasma of Eo decreased significantly after 12 weeks of SeS, (p < 0.01) and 96 weeks of follow up. In parameters of T cell mediated immunity the relative number of CD3 HLADR+ T Ly increased after 24, 48 and 96 weeks of SeS (p < 0.0008, p < 0.009, p < 0.07). Proliferative activity of T Ly to mitogenes PHA and ConcA in LTT decreased significantly after 12, 48, 72 and 96 weeks of SeS (p < 0.0005, p < 0.009, p < 0.04, p < 0.02, respectively). In humoral parameters activation of CP50 decreased after 24, 72 and 96 weeks of SeS to the reference range (p < 0.001, p < 0.03, p < 0.02) and AP50 after 96 weeks, respectively (p < 0.02). The levels of IgG elevated after 24 weeks (p < 0.02), IgA after 24, 48 weeks (p < 0.0007, p < 0.02, respectively). The level of total IgE significantly decreased after 96 weeks of SeS (p < 0.003).

Our pilot clinical study with the CDAs demonstrates the significant changes particularly in functional parameters of both cellular and humoral types of immunity. These results support the immunomodulating effects of SeS. (Tab. 5, Ref. 15.)