Potential of multi-component antigens for tuberculosis diagnosis

Tuberculosis is one of the top ten causes of deaths worldwide. The cause of tuberculosis is a bacterium, Mycobacterium tuberculosis, which has been surviving for centuries. Immunological tests based on detecting the presence of antibodies in the sera of active TB patients against various antigens of M. tuberculosis are useful for diagnosis of TB and offer simple, rapid and cost effective methods most suitable for poor and developing countries. Several recombinant antigens have been reported so far with varying sensitivity individually, yet none had shown sensitivity higher enough to be used in a commercial test. There is a trend of utilizing recombinant DNA technology to make polypeptide chain with two or more different antigenic regions, in order to increase the diagnostic efficiency. In this review, we have made an attempt to combine current studies on the usefulness of the multi-component Mycobacterium tuberculosis antigens in serological tests for the diagnosis of tuberculosis.