Abstract: A test system and procedure for quantitatively assaying biological material for a target immunological substance by means of immunochemical binding of immune complexes, comprising the target substance and its immunospecific conjugate, to insolubilized non-immunospecific factor, such as Clq. A sample of biological material suspected of containing the target substance is introduced into the test system including pre-determined amounts of the target substance and its immunospecific conjugate forming immune complexes having a known degree of chemical binding to the non-immunospecific factor. The amount of target substance present in the test sample is determined according to the deviation from the known degree of immunochemical binding caused by the addition of the sample to the test system, by reference to a standard curve.

Abstract: A 60-like antigens isolated in a one-step reaction from the bacterial cytoplasma of Mycobacteria are useful for the production of diagnostic tests.