Evaluate the Efficiency of A60 Protein from BCG Strain of Mycobacterium Bovis as a Diagnostic Antigen

Tuberculosis is the most common infectious diseases. Current diagnostic methods are either slow or lack enough sensivity or specificity. Several mycobacterial antigens are involved in the complex interaction with the immune system of the host. They can be helpful for mycobacteria diagnosis. Antigen 60 (A60) is thermostable antigen found in Mycobacterium bovis and Mycobacterium tuberculosis. This antigen, are used in ELISA systems design for diagnosis of tuberculosis. The aim of this study is purification of A60 from bacterial cytoplasm and evaluating and compare its efficiency with standard human tuberculin. With filtration chromatography, A60 were purified from other bacterial components. A60 was recognized by agar gel Immnuodiffusion with anti BCG and Anti A60 antiserum, where formed immunopercipitiongen line with anti BCG anti serum and anti A60 anti serum. Molecular weight components of the A60 was obtained using electrophoresis. By chromatography, seven fractions obtained. Dot blot analyzing showed that, cytoplasm and cell wall of BCG contained A60. This test showed that first fraction created maximum color intensity and as a result, the highest amount of A60 was in the fractions one. In agar gel immnuodiffusion, cytoplasm sample and all factions obtained from chromatography showed positive reaction with anti A60 anti serum and fraction one, had highest amount of sediment among the other factions. Molecular weight components of the A60 were identified about 35, 38, 40 and 65 kD. Results of reactions from injected A60 and standard human tuberculin showed the effectiveness of this antigen in comparison with standard human tuberculin. Detection of antibody in the serum of patients is rapid and repeatable method. A60 with 89% sensitivity and 94% specificity could be an appropriate matter for the diagnosis of tuberculosis.With this method, without any advanced and expensive equipments or materials we can achive the desired results as quickly as possible.