Production of β₂‐microglobulin by chronic lymphocytic leukaemia cells in vitro

Abstract

The in vitro production of β2‐microglobulin (β2m) by leukaemic cells was studied in 22 patients with chronic B‐lymphocytic leukaemia (CLL). In addition, the concentration of β2m in serum (S‐β2m) was determined and expressed as percent of the upper normal limit, after a correction for elevated S‐Creatinine values. Patients with progressive disease usually had CLL cells with a high rate of in vitro synthesis and an increased S‐β2m. This was not found in patients with non‐progressive disease. The in vitro synthesis of β2m × the lymphocyte count correlated with S‐β2m in the total material (r = 0.65). The increased S‐β2m frequently observed in CLL may therefore originate from the tumour cells. Hence, S‐β2m is promising as a clinically useful tumour cell‐associated marker in CLL.