Abstract
The population of T-cell subsets, the blastogenic responses of lymphocytes in blood and spleen and splenic NK cell activity were examined in mice transferred from 221C to 12t or 32t environments. The percentage of Thy-1.2 positive cells and Lyt-1.2 positive cells in the spleen decreased after the transfer. However the percentage of Lyt-2.2 positive cells in the spleen was not affected. Thy-1.2 and Lyt-1.2 positive cells in the blood also decreased. The percentage of Lyt-2.2 positive cells in the blood was not affected in mice exposed to 12°C. However, Lyt-2.2 positive cells in the blood decreased on day 1 but increased on day 3 in mice exposed to 32°C. Blastogenic responses of spleen lymphocytes to concanabavalin A (Con A) and pokeweed mitogen (PWM) were suppressed in transferred mice, but responses to lypopolysaccharide (LPS) and phytohemagglutinin-P (PHA-P) were not affected in any group. Blastogenic responses of blood lymphocytes to Con A, PHA-P, and PWM tended to be weaker in transferred mice than in mice kept in the 22°C environment. In particular the response to PWM in mice exposed to 12°C was less than 8 % of that in the 22°C mice. Splenic NK cell activity decreased in transferred mice, but was not suppressed as much as in mice administered 5mg of cortisone acetate. These data show that the number of helper T cells decreases and that the blastogenic responses of T cells and NK cell activity are suppressed in mice transferred from 22°C to 12°C or 32°C environment. It thus seems plausible that wide variations in environmental temperature may encourage infectious diseases and manifestations of latent infections in mice.
