[Study of hypoxia-induced immune injury and its intervention measure]

To explore the characteristic of hypoxia-induced immune injury, its mechanisms and the intervention measure.

The change of immune organ index, T lymphocyte subsets of peripheral blood and immune organ in mice during hypoxia were detected. Lymphocyte apoptosis of immune organ, pathology of lung and kidney in mice were observed. Then by way of prophylaxis we studied the effect of Chinese Traditional Medicine on hypoxia-induced immune injury in mice.

(1) Exposure to hypoxia at 8 000 m simulated altitude for 8 h resulted in marked decrease in CD4+ CD8+ thymocytes and marked increase in CD4+ CD8-, CD4- CD8+ thymocytes (P < 0.01). After 3 days of hypoxia, the mice had a much lower percentage of CD4+ T-cell (P < 0.05). The ratio of CD4+/CD8+ decreased significantly and aforesaid changes of thymocyte were further enlarged. Also mice had a pronounced increase in rates of late apoptosis or necrosis of spleen lymphocyte and thymocyte (P < 0.05). After 6 days of hypoxia, index of spleen was significantly increased (P < 0.05), index of thymus was significantly decreased (P < 0.05) and CD3+, CD4+, CD8+ lymphocyte percentage of spleen were significantly decreased (P < 0.01). Also late apoptosis or necrosis lymphocytes of spleen and thymus were further increased (P < 0.01), viable cell rates of spleen lymphocyte and thymocytes were markedly decreased (P < 0.01), early apoptosis rates of spleen lymphocyte were markedly increased (P < 0.01). There was no significant change in the percentage of CD8+ lymphocyte in peripheral blood during the whole hypoxia period. (2) New Compound Codonopsis Pilosula (NCCP), Xiang Qi Polysaccharide (XQP) and NCCP + XQP could significantly increase the number of peripheral blood CD3+, CD4+ and spleen CD4+, but had no significant influence on the number of spleen CD8+. XQP and XQP+ NCCP could significantly decrease the number of CD4+ CD8+ (P < 0.01), increase that of CD4+ CD8- (P < 0.01), and had no significant influence on CD4- CD8+ in thymus. However, NCCP didn't influence the component of thymocytes.

After hypoxia at 8 000 m simulated altitude decrease of lymphocyte of periphery in mice may be related with increase of apoptosis and necrosis of lymphocyte, and with increase of distribution of lymphocyte to lung in early period of exposure. NCCP and XQP have hopeful prospect in intervention study of hypoxia-induced immune injury.