[Modulation of proliferation of peripheral blood lymphocytes after irradiation of volunteers with polychromatic visible and infrared light].

Effects on human immune system of visible and infrared (IR) radiation, the dominating types of solar light on Earth, still remain poorly studied. In the present work, a small area of the volunteers' body surface was irradiated with polychromatic visible + IR polarized (VIP) light, whose spectral range is close to the natural one (400-3400 nm, 12 J/cm2), and spontaneous and phytohemagglutinin (PHA)-induced DNA syntheses were studied by radiometric method in lymphocytes (Lym) of peripheral blood. This Irradiation stimulated both spontaneous and PHA-induced DNA synthesis in Lym but only in volunteers with initially decreased parameters of synthesis (on average, by 2.5 and 2.7 times, respectively), which was recorded 24 h after irradiation of volunteers, and after a 72 h cultivation of separated mononuclears. In the parallel experiments, blood of each volunteer was irradiated in vitro. Besides, by modeling situation in vivo, when a small amount of transcutaneously photomodified blood contacts its much larger circulating volume, the irradiated and non-irradiated samples of autologous blood were mixed at a 1:10 volume ratio. In Lym with the initially decreased synthesis level, the spontaneous synthesis elevated by 2 and 3 times, respectively, whereas stimulation of PHA-synthesis was observed only after addition of the irradiated blood to the intact one (by 2.2 and 1.6 times, respectively). A high degree of positive correlation in changing the studied parameters is revealed in irradiation of blood in vivo and in vitro. This makes it possible to associate the light-stimulating effect on Lym of the entire circulating blood with transcutaneous photomodification of its small amounts, and with action of such blood on the rest of blood. A similarity in the direction and additivity of mitogenic effects of VIP light and PHA was revealed. The obtained data enable us to suggest that therapy employing polychromatic visible and IR light would promote presumably an increase in the number of Lym in peripheral blood and an enhancement of their response to antigenic stimulus.