ABSTRACT
<p><b>OBJECTIVE</b>To investigate effects of the variation of immune function in high humidity environment in different time, and lay a foundation for further study of the related mechanism.</p><p><b>METHOD</b>Thirty SD rats were divided into 3 groups (n = 10): 20 day group, 40 day group in 90% relative humidity chamber and control group in normal relative humidity. Peripheral blood and spleens were collected to detect the levels of T lymphocyte subsets by Flow Cytometery.</p><p><b>RESULTS</b>In peripheral blood of the 20 day group rats, the CD3+ %, CD4+ %, CD8+ % and CD4+/CD8+ were 52.91 +/- 6.27, 37.80 +/- 4.11, 14.85 +/- 3.73 and 2.72 +/- 0.82 separately. Expect CD3+ %, they all had significant differences (P < 0.05). In addition, the data of the 40 day group rats showed no diversity in statistics. In spleen, CD8+ % of the 20 day group rats was 6.23 +/- 2.87 with significant differences (P < 0.05) and IgG, IgA and IgM did not change a lot in blood serum of the high humidity groups except C3 of the 20 days group (P < 0.05).</p><p><b>CONCLUSION</b>In high humidity environment, the immune function of the rats increased in the initial stage. As time went on, the immune function gradually went to normal level through the self adjustment.</p>