Differential expression of very late activation antigen-3 (VLA-3)/VLA-4 in B-cell non-Hodgkin lymphoma and B-cell chronic lymphocytic leukemia

Abstract

The expression of beta 1 (very late activation antigens, VLA 1–6) and beta 2 integrins (leukocyte adhesion molecules [Leu-CAM]) in cell suspensions from the peripheral blood of 70 patients with B-cell chronic lymphocytic leukemia (B-CLL), 15 patients with leukemic lymphocytic lymphoma of intermediate differentiation (IDL), as well as from the lymph nodes of 20 patients with low/intermediate-grade non- Hodgkin's lymphoma (NHL) was studied with the aim of characterizing their adhesive phenotype and evaluating its relationship to clinical behavior. CD11a(LFA-1) was more expressed in NHL and IDL than in B-CLL (P = .047), although it was demonstrable in 74.2% of cases; CD11c was more expressed in B-CLL (P less than .0001), and its expression was preserved in almost all of the cases of small lymphocytic lymphoma. In NHL patients, including the cases of IDL, VLA-3 expression was observable in 8 of 35 cases (although always at a low level of intensity), while VLA-4 was almost constantly expressed in a way that was similar to its expression in control normal B cells. On the contrary, in B-CLL patients, VLA-3 was expressed (prevalently at high levels) in 87.1% of cases and VLA-4 only in 37.1%. No correlation was found between adhesion molecule patterns and the clinical features of the diseases. The biofunctional significance of the imbalance of VLA-3 and VLA-4 expression in B-CLL is not easy to explain, but it has undoubted intrinsic value as an additional marker for distinguishing B- CLL from, in particular, those B-cell neoplasms (such as IDL) that share many of the immunocytomorphologic characteristics and the putative normal counterpart (the mantle zone) of B-CLL.