Seasonal aspects of immunological reactivity of the human and animal organism.

In a study of 95 practically healthy humans and in experiments on 148 animals (dogs, rabbits, rats), an attempt was made at assessing seasonal effects on immunological reactivity. The content of IgM antibody-forming cells was determined as well as the activity of blood and lymphoid NK and K cells and number of E rosette-forming peripheral blood lymphocytes. The most pronounced changes were observed in the specific immune response (IgM antibodies and K cells), which was enhanced during autumn and winter. Seasonal fluctuations in E rosette-forming cells and IgE antibodies were less extensive. The activity of NK cells was found to be relatively stable.