[Diagnosis of tuberculosis by immunocapture of the tuberculous bacillus (using magnetic beads)]

Tuberculosis is worldwide considered as a major health problem with high morbidity and mortality rates. Diagnosis of tuberculosis can be problematic. Microscopy, as the basic diagnostic method, stands inadequately alone due to a low sensitivity, and culture suffers from being time-consuming. A rapid, sensitive and simple diagnostic test, applicable in the field is therefore highly needed. A diagnostic method for the detection of M. tuberculosis by immunocapture technique has been developed using magnetic beads coated with polyclonal anti-M. tuberculosis. The detection of captured bacilli using biotinylated anti-APA monoclonal antibody (APA is a minor secreted antigen) was found more sensitive than microscopy. The results suggest that the development of a rapid strip test to detect major antigen could be a useful tool for the control of tuberculosis.