The chronic B-cell leukaemias

B-cell chronic lymphocytic leukaemia with CD8 expression: report of 10 cases and immunochemical analysis of the CD8 antigen

We report 10 cases of B-cell chronic lymphocytic leukaemia (B-CLL) with expression of the T-cell antigen CD8. The majority of patients had typical B-cell CLL with stable and non-progressive stage A(O) disease except for more common expression of lambda light chain and CD25. Two patients had progressive disease and required therapy, one with atypical morphological and phenotypic features. The incidence of CD8 expression was approximately 0.5% of B-CLL patients from our institutions. Immunoprecipitation of the CD8 antigen from four of these B-CLLs showed identity to the CD8 antigen expressed on T cells with precipitation of CD8alpha bands of molecular weight approximately 34 kD. In view of the known intracellular signalling mechanism of CD8 using the tyrosine kinase p56-lck, we studied p56-lck expression by Western blot and found lack of consistent expression of the CD8 surface antigen, with most lacking p56-lck. Our report indicates that CD8 expression in B-CLL is probably underrecognized but is not a marker of disease progression. The CD8 on the B-CLL surface is immunochemically identical to the antigen on T cells, but is not accompanied by its usual signalling mechanism of p56-lck tyrosine kinase and therefore is unlikely to be a functionally active receptor.

In vivo binding of mouse IgG via polyreactive surface IgM abrogates progressive lymphocytosis in prolymphocytic leukemia

Surface IgM expressed by malignant CD5+ B-cells from patients with B-chronic lymphocytic leukemia (B-CLL) has previously been shown to bind mouse Ig in what appears to be an example of polyreactive antigen-binding activity. This report demonstrates the in vitro and in vivo binding of mouse Ig to the surface of malignant B-cells from a patient with B-cell prolymphocytic leukemia (B-PLL). In vitro studies showed that K121, a mouse monoclonal antibody, bound to the B-PLL cells via the same low-affinity binding interaction demonstrated to occur between mouse Ig and surface IgM expressed by B-CLL cells rather than in the conventional sense against a specific antigen via its antigen-binding site. With the view to using this phenomenon to target malignant B-cells, it was important to determine whether the low-affinity interaction also occurred in vivo. Infusions of K121 totalling 286 mg were administered to a B-PLL patient over 7 days. Binding of K121 to circulating B-PLL cells was demonstrable after the administration of 36 mg of antibody and was preceded by the appearance of free antibody in the serum. Throughout the period of the infusion, the rapid rise in the peripheral blood white cell count normally observed after leukopheresis was abrogated. However, the count rose markedly after cessation of the antibody infusion in parallel with a decrease in both free and cell-bound K121. There were no observable side effects and no host immune response to either species specific or idiotypic determinants on the mouse Ig was detected. The in vivo binding of mouse Ig together with the previous in vitro data suggest the potential for a novel targeting mechanism using a region of the mouse Ig molecule to target polyreactive Ig expressed by malignant cells in B-CLL and B-PLL.

The relevance of cytological studies and Ki-67 reactivity to the clinical course of chronic lymphocytic leukemia

The aim of the study was to investigate whether the growth fraction and cytology of peripheral blood and lymphoid tissues relate to response to treatment in CLL. Growth fraction was assessed using the monoclonal antibody Ki-67. Peripheral blood (PB) films and lymph node and spleen touch imprints or aspirates were examined in 35 patients (pts) with CLL: smouldering CLL (4 pts) (no therapy), progressive CLL but responsive to chlorambucil and cyclophosphamide (15 pts) and resistant CLL (16 pts). Cytological studies of lymphoid tissues showed that pts with resistant CLL had an increased proportion of prolymphocytes and blasts and the highest Ki-67 expression (mean 6,6%). PB morphology was not different between the groups of resistant and responsive CLL. However, the cases with resistant CLL showed a higher percentage of Ki-67 positive PB cells (p<0,05). Four pts with indolent CLL had typical CLL morphology in the PB and the lowest numbers of prolymphocytes and blasts with Ki-67 positive cells in lymphoid tissues.

Chronic lymphocytic leukaemia at a county hospital in southern Sweden

We have studied retrospectively patients with chronic lymphocytic leukaemia (CLL), at Ryhov, Jönköping, Sweden during a 10-year-period. This unselected cohort (n = 59) from a well-defined geographical area is suitable for describing the natural course of the disease. The CLL was diagnosed incidentally in the majority of cases. Median-age at diagnosis was 71 years and the male:female ratio was 1.3:1. The diagnosis was based on morphology in 66% and in 33% immunophenotyping specified the diagnosis of B- or T-CLL. At diagnosis 66% were in Rai-stage O/I or Binet-stage A. There were 36% untreated patients and their median-survival was 108 months compared with 84 months for the whole cohort and 72 months for the treated patients. Malignancies were seen in 31% and infections in 83%. Intercurrent diseases played an important role in the survival. During the observation time, only 54% of the deceased patients had died due to the CLL.

Chronic lymphocytic leukaemia with upper airway obstruction

We report a case of B-cell chronic lymphocytic leukemia in a 58 year old female in whom the clinical course was dominated by upper airway obstruction due to massive enlargement of the palatine and later the lingual tonsils. The peripheral blood morphology and immunophenotype were typical of chronic lymphocytic leukaemia with expression of CDl9+, CD20+, CD5+, CD23+ and HLA-DR+ together with weak, surface immunoglobulin with monoclonal lambda light chain. Therapy included surgical removal of the palatine tonsils and later chemotherapy, both of which provided temporary relief of obstruction before recurrence of obstruction at the site of the lingual tonsils. Lasting relief from mass effect and obstruction only occurred following localised radiotherapy to Waldeyer's ring.