Cd40 ligand/cd40 deficiency

Abstract

CD40 is a surface antigen expressed on B cells. The C'D40 ligand (CD40L) is expressed on activated T cells. Interaction between CD40 and CD40L is critical for proliferation and isotype switching in the context of a response to a T-celldependent antigen. Patients with X-linkcd hyper-IgM syndrome (HIGMX-1) in their CD40L gene are unable to switch from IgM to lgG, IgA and IgE. Mice with a disrupted CD40 gene fail to undergo isotype switching to T-cell-dcpcndent antigens but respond normally to T-independent antigens. © 1995 S. Karger AG, Basel.