[Rosette formation test with mouse erythrocytes in chronic lymphatic leukosis: correlation with other membrane receptors].

The lymphocyte subpopulations of CLL patients have been studied. IgM and IgD membrane-associated immunoglobulins alone or in combination have been found, IgG being present in only one case. A marked increase in mouse-complement receptors (as shown by the EACt rosettes) as compared with human complement receptors (as shown by the EACa rosettes) was observed. The population of SIg-bearing lymphocytes was significantly greater than that of complement bearing lymphocytes. Moreover a mean percentage of 60.7 +/- 17 of the leukaemic lymphocytes formed rosettes with mouse red blood cells. In a significant number of patients the E-rosettes forming cells were also increased.