Study on apoptosis of THP-1 cells induced by Mycobacterium tuberculosis 19 kDa lipoprotein

Objective: To abserve the influence of Mycobacterium tuberculosis 19 kDa(Mtb P19) on the apoptosis of THP-1 cells.Methods: Mtb P19 was prepared from cultured Mtb H37Ra.Phorbol myristate acetate-differentiated THP-1 cells were incubated with P19 at the concentrations from 5 μg/ml to 20 μg/ml at 37℃,5% CO₂ for up to 4 hours.The change of cells was observed by Wright-Giemsa stain,and the apoptosis rate was detected by flowcytometry.Results: Mtb P19 could induce THP-1 cells apoptosis at final concentration of 5 μg/ml,and the apopotosis rate increased with the concentration of P19(P<0.01).Round shrinkage,pyknosis or nuclear fragmentation were observed in some cells by Wright-Giemsa stain.Conclusions: Mtb P19 induces apoptosis in THP-1 cells in a dose-dependent manner.