CD54 and CD62L expression by lymphoid cells in acute lymphoblastic leukaemia in children.

Altered expression or function of adhesion molecules on leukaemic blasts may contribute to the evolution and biological behaviour of acute leukaemia. This work studies the expression of CD54 and CD62L by lymphoid cells and the serum level of the shed form of L-selectin (sL-selectin) in children with acute lymphoblastic leukaemia (ALL) at initial diagnosis and after first remission, and their relationship to disease activity and subtype. The study is conducted on 20 children (age range 2-10 years) newly diagnosed with ALL and admitted to Alexandria University Children's Hospital. Ten apparently healthy children of matched age and sex serve as a control group. Expression of CD54 and CD62L on mononuclear cells is detected by monoclonal antibodies using flow cytometry. Serum sL-selectin is measured by enzyme-linked immunosorbent assay (ELISA). B-cell ALL was the most common subtype (45%), followed by T-ALL (35%) and C-ALL (20%). CD54 and CD62L mean cellular expression, as well as serum sL-selectin level, were significantly higher at diagnosis than both after remission and in the control group. Univariate analysis showed that the presence of mediastinal mass, high leucocyte count, central nervous system involvement and low CD54 were significant predictors of mortality in children with ALL.