[Sera showing the ability of erythrocyte panagglutination]

The properties of a factor causing panagglutination of erythrocytes are described. The factor was found in the sera of three patients when blood was tested for transfusion. Panagglutination appeared in the indirect antiglobulin test when the erythrocytes were being washed with 0.15 M NaCl without addition of phosphate buffer. The method for cross testing in such cases was elaborated, with washing the cells with 0.15 M NaCl buffered with phosphates.