Objective:To discuss the influence of organic selenium on the immune effect of Bacille Calmette-Guerin(BCG). Methods:C57BL6/J mice were randomized into 4 groups:"BCG+Se"mice group were intracutaneously inoculated with BCG and orally fed with yeast-based selenium(Se);BCG mice group were immunized with BCG intracutaneously;Se mice group were im- munized with normal sodium and fed orally with Se;control mice group were immunized with normal sodium and fed orally water without Se.The mice were sacrificed after 4weeks or 8weeks to isolate the spleen mononuclear cells.T lympholeukocyte proliferation testing(stimulation index

SI)

cytotoxic T lympholeukocyte(CTL)function testing as well as levels of IL-2 and IFN-γand mRNA levels of granzyme B and perforin were employed to assess the effect of vaccine for Mycobacterium tuber- culosis.They were determined by MTT assay

ELISA assay and RT-PCR

respectively.Results:The levels of 6 detected items in"BCG+Se"group and BCG group were significantly different from those in the control group(P<0.05).And the SI

IL-2

IFN-γand CTL cytotoxic activity in group"BCG+Se"(4weeks:2.61±0.24

(172.56±9.34)pg/ml

(131.89±3.32)pg/ml

(43.91±3.21)%; 8weeks:2.32±0.31

(138.04±9.67)pg/ml

(129.17±2.41)pg/ml

(39.92±6.45)%)were significantly higher than that of group BCG(4weeks:(1.62±0.14)

(134.06±9.60)pg/ml

(105.89±4.62)pg/ml

(30.46±7.97)%;8weeks:1.61±0.19

(101.42±7.76)pg/ml

(102.00±5.41)pg/ml

(28.14±5.70)%(P<0.05)).Conclusion:The results suggest that there exists an immunologic synergy be- tween organic selenium and BCG and that selenium could promote the cellular immunologic responses in BCG immunized mice.