Determination of Anti-tuberculous Antibody Against Triton X-100 Solubilized Protein ( TSP ) Antigen of Mycobacterium tuberculosis in the Sera of Patients with Pulmonary Tuberculosis

ABSTRACT

Some of the proteins of mycobacteria are preferentially associated with the cell wall and are powerful immunogens, and humoral antibody responses to these mycobacterial antigens may occur in patients with tuberculosis. In this study, Triton X-100 solubilized protein (TSP) antigen was isolated from Mycobacterium tuberculosis H37Rv by overnight shaking with 1% Triton X- 100/PMSF and 10-90% ammonium sulfate precipitation. IgG and IgM antibody levels against TSP, crude protein from the unheated cultrue filtrate (CF#) and 30 kDa antigens were determined in the sera of 80 patients with pulmonary tuberculosis and 99 healthy controls with PPD (+) and (-). High IgG reactivity to TSP and CF antigen was observed in tuberculosis patients. Mean IgG antibody titers against all of three mycobacterial antigens were differed significantly (P<0.01) between patients and controls but IgM showed no difference. By the cut-off value adding 2 standard deviation to the mean absorbance of controls, the sensitivity and specificity of the IgG antibody to TSP antigen were 93.9% and 77.5%. The specificity to TSP antigen was a litttle higher than those obtained by CF and 30 kDa antigen. From the above results, the TSP antigen may be useful for the serodiagnosis of tuberculosis.