Effect Of Bacillus Calmette-Guerin(BCG) Vaccine Or(/and) Tubercle Germs On Rat T Lymphocyte Subsets Of Peripheral Blood

Objective To observe dynamically the effect of Bacillus Calmette-Guerin (BCG) vaccine or(/and) Mycobacterium tuberculosis on rat T lymphocyte subsets of peripheral blood and compare with T lymphocyte subsets of lung tissues, and evaluate the immunological function of BCG vaccine and the immunological impairment of Mycobacterium tuberculosis.Methods 40 SD rats were randomized into four groups as normal control group, BCG vaccine inoculated group (BCG group), Mycobacterium tuberculosis group (tuberculosis group) and BCG vaccine inoculated and Mycobacterium tuberculosis injected group (BCG-tuberculosis group). The BCG group and the BCG-tuberculosis group were injected with the live BCG vaccine 0.01mg in the abdominal derma at the beginning, after three months the normal control group and the BCG-tuberculosis group were injected in the tail vein with standard person type Mycobacterium tuberculosis H37Rv 0.01mg. For comparison, another two groups were injected simultaneously with the same volume normal saline. T lymphocyte of peripheral blood and lung tissues was measured by flow cytometry that labeled with bicolor direct-scale monoclonal antibody, and pulmonary lesions were examined pathomorphologically and pasted on the sheet to do acid-fast stain. Results T lymphocyte subsets is no significant difference between the BCG vaccine inoculated group and the non-BCG vaccine inoculated group( P>0.05). The first month after the injection of Mycobacterium tuberculosis, the level of CD8 in the BCG group is lower than the normal control group, the level of CD8 and CD3 in the tuberculosis group and the BCG-tuberculosis group are lower than the normal control group (P<0.05). The second month after injection , the level of CD4 and CD4/ CD8 ratio in the tuberculosis group are lower than th e normal control group, the level of CD8 in the BCG group is lower than another three groups, but DP(CD3+CD4+CD8+ )higher than the normal control group, CD4/CD8 ratio higher than the tuberculosis group and lower than the BCG-tuberculosis group(P<0.05). The third month after injection, the level of CD8 in the normal control group is higher than the tuberculosis group and the BCG group (P<0.05). the level of CD8 of peripheral blood in the BCG group ,the tuberculosis group and the BCG-tuberculosis group is lower than lung tissues. The level of CD4 of peripheral blood in the normal control group and the tuberculosis group is higher than lung tissues, the level of CD3 in the BCG-tuberculosis group lower than lung tissues. The CD4/CD8 ratio of peripheral blood in the BCG group and the BCG-tuberculosis group is lower than lung tissues. the level of DP(CD3+CD4+CD8+ )of peripheral blood in the BCG group is lower than lung tissues.The dynamic variety of peripheral blood T lymphocyte in the four groups: the level of CD8 in the normal control group begins to step up after three months, ascends the tallest level at the sixth month, and then decrease again. The variety of CD4/CD8 ratio is on the contrary (P<0.05). The level of CD3, CD8 and DN( CD3+ CD4- CD8-) in the BCG group declines the lowest level at the third month, recovers roughly the normal level at the sixth month, and then descends again; The level of CD4 and the ratio of CD4 to CD8 descends after five months.( P<0.05) . The level of CD3 and CD8 in the tuberculosis group falls at one month after the injection of Mycobacterium tuberculosis, the level of CD3 resumes normal but CD8 attends the tallest level at the second month, and then decreases again; at the second month after the injection of Mycobacterium tuberculosis, the level of CD4 declines the lowest and then sets up gradually, but is still lower than the normal level( P<0.05). The level of CD3, CD4, CD8 and DN after the injection of Mycobacterium tuberculosis ranges between the tuberculosis group and the BCG group on the whole.Conclusions BCG vaccine protection immunity multiplies the CD4+ T cell, CD8+ T cell and DP T cell of peripheral blood and pulmonary, and Mycobacterium tuberculosis restrains CD4+ T c...