[Adaptation of monoclonal test sera for antigen determination in the positive direct Coombs test].

Monoclonal reagents of IgM type now allow to test some red blood cell antigens (K; Jk a; Jk b) by the tube centrifugation method at room temperature for which an indirect antiglobulin test was necessary before. This enables to test antigens also when the direct antiglobulin test is positive, provided that there are no disturbances by supplements contained in the sera. We examined monoclonal blood group sera of different manufacturers for their ability to test antibody-coated erythrocytes; sometimes we found great differences between the different products. Therefore we recommend to add this test to the other criteria of quality control, especially when it is necessary to test antigens in patients with positive direct antiglobulin test.