In chronic lymphocytic leukaemia the non-malignant B cells do not mature to produce IgG and IgA because of an interaction with CD30+ T cells.

In patients with chronic lymphocytic leukaemia antibody production by B cells is severely impaired and this is associated with increased susceptibility to bacterial infections. The mechanisms behind the immune defects have remained elusive. In the February issue of Nature Immunology, researchers from Cornell University, New York, show how leukaemia cells interfere with normal B cell function.

T cells express a key molecule (CD30) in the presence of leukaemic cells. Using in vitro experimental models, Andrea Cerrutti and colleagues demonstrate that if CD30⁺ T cells interact with B cells during an immune response, the non-malignant B cells do not progressively mature to switch on various required antibody types (Nat Immun 2001, 2:150-157).

It may therefore be possible to use this research to develop a...