[Effects of Brucella phosphoglucomutase on inducing infection of trophoblastic cells].

OBJECTIVE: We studied the biological function of Brucella phosphoglucomutase (pgm) gene, and detected the changes of human trophoblast cell invaded by the Brucella pgm mutant and PGM protein.

METHODS: Human trophoblast cells were infected by the pgm mutant and PGM protein. The changes of cytokines were detected by enzyme-linked immunosorbent assay, and morphology of cells was identified.

RESULTS: PGM protein was purified, and pgm mutant was constructed. The sera of mice immunized by pgm mutant were negative by agglutination test and Standard Tube Agglutination Test for Brucellosis. The cellular morphology of human trophoblast cells infected pgm mutant or PGM protein changed. The adhesion and infection of the pgm mutant reduced more than Brucella vaccine strain M5-90, and human trophoblast cells partially cracked off. The activity of IL-6, TNF-alpha or lactic dehydrogenae increased in human trophoblast cells infected by the pgm mutant more than Brucella vaccine strain M5-90 (P < 0.01), but not for IL-10. Lactic dehydrogenae in human trophoblast cells infected by the PGM Protein increased more than sodium phosphate buffer (P < 0.01), whereas IL-6 and TNF-alpha decreased in human trophoblast cells less than sodium phosphate buffer (P < 0.05).

CONCLUSION: The results suggest that the pgm mutant of brucella and PGM protein had the cytotoxic effect for human trophoblast cells with cellular morphology and changes of cytokines.