A THROMBOCYTE CONSUMPTION TEST FOR THE DEMONSTRATION OF AUTOANTIBODY-LIKE SERUM FACTORS.

The capacity of blood platelets to attach themselves aspecifically to antigen-antibody complexes in the presence of complement can be utilized for the demonstration of antibodies formed against homologous tissues.A mixture of the serum-, antigen-complement, and of human thrombocytes is incubated, and the number of thrombocytes in the supernatant is ascertained and referred to a standard. Measurements less than 85% of the standard are regarded as positive. Sera collected from patients with ;protracted' acute or chronic hepatitis and cirrhosis were found to be positive with the new method in 68.0% of the cases; the corresponding figures were 26.3% for ;non-protracted' acute hepatitis and 18.1% for diseases of the bile duct. No positive reaction occurred in other internal diseases studied or in healthy persons, but 40% of subjects with diverse infections gave positive results possibly because of autoantibody formation against tissues damaged by the infections. Comparative examinations suggest that the thrombocyte consumption test is more specific than the antihuman globulin consumption method.