sera from 38 tuberculous patients and 62 healthy controls ( 31 ppd skin test positive and 31 negative ) were assayed , by enzyme-linked immunosorbent assay ( elisa ) , to test the activity of igg and igm antibodies against purified protein derivative ( ppd ) antigen and a phenolglycolipid antigen ( plg-tb 1 ) isolated and purified from mycobacterium tuberculosis strain canetti .
C0034131
purified protein
C0041296
tuberculosis