RESUMO
We describe a child suffering from recurrent bacterial infections whose cells exhibited laboratory findings compatible with the leukocyte adhesion deficiency (LAD) syndrome. Surface marker analysis with monoclonal antibodies (MAbs) to the individual alpha and beta chains of LFA-1/Mac-1/p150,95 antigens revealed that the patient's neutrophils did not express the common beta chain and LFA-1/p150,95 alpha subunits, but reacted weakly with four different MAbs specific for the Mac-1 alpha chain; however, no glycoprotein was immunoprecipitated from the patient's cells using the same anti-Mac-1 alpha MAbs. Functional analysis of the patient's phagocytes revealed many of the defects in adherence-dependent functions (adherence, chemotaxis and phagocytosis) described in patients with LAD. The studies performed on the phagocytes of the patient's relatives showed normal phenotypes and function, suggesting the possibility of a non heritable form of disease in this family.
