The regulatory effect of polychromatic (visible and infrared) light on human humoral immunity

Abstract

The immunological effects of visible and infrared light from laser and non-laser sources have remained insufficiently studied, which has restricted the use of light in the treatment of diseases associated with immune system disorders. The present randomized, placebo-controlled double-blind trial was designed to study changes in the humoral immunity of a large group of volunteers after exposure of a small body area to polychromatic visible and infrared polarized (VIP) and non-polarized (VInP) light (400–3400 nm, 95% polarization, 40 mW cm⁻², 12 J cm⁻² and 400–3400 nm, no polarization, 38 mW cm⁻², 11.2 J cm⁻², respectively). Serum immunoglobulins (Ig) M, A, and G were determined turbidimetrically, and the immune complexes (ICs) by precipitation with 5% polyethylene glycol and subsequent spectrophotometric analysis. A single VIP irradiation induced an average rapid rise in serum IgM levels of 13% (p < 0.05). By the end of the 10 day course, it had exceeded the baseline level by 26%, with an increase in IgA levels of 17 and of 12% (p < 0.05) one week after the last session. In subjects with a high IC content, it decreased rapidly to the normal level. A single exposure of volunteers to VInP light rapidly produced changes similar to those observed on VIP irradiation, but with an increase in IgM 2.3 to 3 times lower, independent of the initial levels. On the other hand, VInP light exposure decreased the IC content more than VIP light.