An immunofluorescence test for detection of antibodies to Mycobacterium tuberculosis.

An immunofluorescence (I.F.) test for detection of antibodies to M. tuberculosis has been developed. The antigen utilized in this test is polymerized tuberculin which is obtained by treating acidified old tuberculin wid rhesus monkeys the I.F. titres rose as the disease progressed and in general were higher in the animals with severe disease and lower in less affected animals. In humans it was found to 100% skin negative persons were negative at 1 :10 and that 100% tuberculin skin test positive persons without active disease were negative at 1 :20. Sera from activt was shown to be sensitive and appears to distinguish infected individuals with active disease from those infected cases without active disease. In addition, the test may be of value in monitoring chemotherapy.