Cytoplasmic immunoglobulins in chronic lymphocytic leukemia B cells

Abstract

It is generally assumed that chronic lymphocytic leukemia of B cell origin (B-CLL) is characterized by the presence of surface membrane immunoglobulins (SmIg) and by the absence of cytoplasmic immunoglobulins (CyIg). In a variable number of cases SmIg are not detectable because of their low density on the cellular surface. Because a constant presence of CyIg in 20 subjects suffering from B-CLL has been reported recently, we reexamined 15 SmIg-negative and 10 SmIg- positive B-CLL patients by SmIg and CyIg determinations. We used a direct immunofluorescence method on peripheral blood mononuclear cells for the detection of SmIg and, after fixation, for CyIg. CyIg were detectable in 24 out of 25 cases, with a fluorescence intensity ranging from weak to moderate. The existence of frequent negative results for CyIg determination in B-CLL reported in the literature probably depends on the low sensitivity of the method used. We conclude that CyIg determination is useful in phenotyping every B-CLL patient, especially SmIg-negative ones.

Detection of light chain restriction in chronic B-lymphoid leukaemia and B-non-Hodgkin's lymphoma

“…Investigation of B-lymphoid chronic leukaemias using immunofluorescence and flow cytometry failed to demonstrate light chain restriction of surface membrane immunoglobulin in 0-20% (Smith et al 1984;Freedman et al 1987;Marsden & Lowenthal 1987). Detection of cytoplasmic light chains in B-chronic lymphoid leukaemia patients using polyclonal antibodies is a very sensitive technique (Pianezze et al 1987;Bardales et al 1989). It was demonstrated, that through the use of kappa-lambda analysis with polyclonal antibodies, large numbers of B-non-Hodgkin's patients with otherwise unsuspected blood involvement can be shown to have circulating monoclonal B cells (Smith et al 1984;Liegler et al 1980).…”

B‐cell chronic lymphocytic leukaemia stage 0. An immunophenotypic study of 66 cases and comparison with B small cell lymphomas*

“…In the literature, the lymphocytes of B-CLL are usually reported to be HLA-DR, EmR, SIg (weakly) CD5, CD19, CD20, CD21, CD23 positive and CD35, CD10, CD38 negative (2,(19)(20)(21)(22)(23)(24). However, in some cases no SIg (13,20,(25)(26)(27) or no CD5 antigen were detected (13,21,28,29). The occurrence of some antigens such as CDlO and CD38 is controversial.…”

Surface immunoglobulin on B lymphocytes as a potential target for specific peptide ligands in chronic lymphocytic leukaemia

“…Chronic lymphocytic leukaemia (CLL) is characterized by proliferation of a single B-or T-cell clone, with the former being the most frequent (around 95%). B-cell CLL (B-CLL) has clonal immunoglobulin in the cytoplasm (Pianezze et al, 1987) as well as on the cell surface (Aisenberg & Bloch, 1972), although in lower amounts than in normal B cells (Dighiero et al, 1980). Surface immunoglobulin is a hallmark of B cells and constitutes an obvious homing moiety for cell-specific targeting.…”