[Deposits of immunoglobulins in the cells of chronic lymphocytic leukemia (author's transl)]

Intracellular inclusion bodies in 14 patients with B cell lymphoproliferative disorders

Two types of intracytoplasmic inclusion were detected by immunofluorescence microscopy in 12 patients with chronic lymphocytic leukaemia and two patients with a leukaemic phase of well differentiated lymphocytic lymphoma. Further analysis with light- and electron microscopy, showed that most inclusion bodies were rod-like crystalline structures. However, in three patients they consisted of amorphous vesicular precipitates. Immunological studies revealed the presence of immunoglobulins of the same class and type at the cell surface as well as in the inclusion bodies. The monoclonal immunoglobulins were all of lambda type except in two cases. The origin of immunoglobulin inclusion bodies in B cell malignancies is discussed in relation to published data and our own observation in one patient followed during treatment.

Unusual intracytoplasmic immunoglobulin inclusions in chronic lymphocytic leukaemia

Unusual intracytoplasmic immunoglobulin inclusions were found by immunofluorescence in three patients with chronic lymphocytic leukaemia. The inclusions contained the same immunoglobulin chains as those detected on the plasma membrane, except for delta chains which were expressed on the cell surface and not in the cytoplasmic inclusions. The cytoplasmic staining persisted throughout culture for 8 or more days. An initial study of patients 1's cells showed that the inclusions contained only mu chains, and kappa chains gradually became apparent after in vitro culture. In a second study, the fresh lymphocytes contained both mu and and kappa chains. Initially, biosynthetic experiments showed production of mu chains which polymerized in the cytoplasm and were not secreted. Subsequently there was synthesis of heavy and light chains which assembled into monomeric subunits that were retained and secretion of free light chains. The apparent molecular weight of these immunoglobulin chains was larger than that of their secretory counterparts. Immunoelectronmicroscopy revealed cytoplasmic mu chains in strands of endoplasmic reticulum. In the two other patients, immunofluorescence displayed unusual staining patterns of bright networks in perinuclear areas.

Auer bodies in acute lymphocytic leukaemia and B-cell lymphoma: evidence for a common progenitor of myeloid and lymphoid cells?

In a patient with acute lymphocytic leukaemia (pre-T ALL) and another patient with leukaemic generalization of B-cell lymphoma Auer bodies were found in a few immature cells. The diagnosis in both cases was based on clinical grounds, morphology, cytochemistry, and immunological marker analysis of the blasts. Auer bodies are known to be a marker of high significance for acute non-lymphocytic leukaemias. Therefore the findings described suggest mixed leukaemias with either T-cell or B-cell predominance. It provides further evidence for the existence of a common progenitor of myeloid and lymphoid cells.

B-cell lymphoma lacking Fc- and C3d-receptors

Various cell surface markers were studied in a patient with lymphosarcoma cell leukemia. The B-cell derived feature of the neoplastic cells could be identified by demonstration of monoclonal surface immunoglobulin of IgM-kappa type of high density synthesized by the cells. Interestingly, there were no Fc- nor C3d-receptors demonstrable using various techniques. Only 22% of the leukemic cells expressed C3b receptors. The failure of rosette formation with mouse erythrocytes was an additional surface feature distinguishing from ordinary chronic lymphatic leukemia of the B cell type. The phenotype of the leukemia cells is discussed as corresponding to that of a less differentiated B lymphocyte.

Chronic lymphatic leukaemia: correlation of immunofluorescent characteristics and clinical features

60 patients with chronic lymphatic leukaemia (CLL) were classified according to the immunofluorescent characteristics of their lymphocytes. A group expressing surface membrane (Sm) IgM had a significantly less aggressive disease than those expressing a mixture of SmIgM and SmIgD or those without surface immunoglobulin. The patients were older than in most comparable series and had a 2:I preponderance of women. It is suggested that especially among old ladies there is a benign variety of CLL which expresses SmIgMK, and that determination of the SmIg class in CLL has prognostic value.