CD40

Definition: CD40 is a cell surface receptor that is expressed on the surface of all mature B cells, most mature B-cell malignancies, and some early B-cell acute lymphocytic leukemias, but is not expressed on plasma cells. It is also expressed on monocytes, dendritic cells, endothelial cells, and epithelial cells.

Pathology

Mutations in CD40 or CD40 ligand (CD40L) are known to cause hyper-IgM syndrome, in which T-cell and B-cell interaction is disrupted, thus preventing isotype switching from IgM and a subsequent selective increase in IgM at the expense of other immunoglobulins.

See also

 CD40L