CD20 Antibody

This gene encodes a member of the membrane-spanning 4A gene family. Members of this nascent protein family are characterized by common structural features and similar intron/exon splice boundaries and display unique expression patterns among hematopoietic cells and nonlymphoid tissues. This gene encodes a B-lymphocyte surface molecule which plays a role in the development and differentiation of B-cells into plasma cells. This family member is localized to 11q12, among a cluster of family members. Alternative splicing of this gene results in two transcript variants which encode the same protein. [provided by RefSeq, Jul 2008]

MS4A1: This protein may be involved in the regulation of B-cell activation and proliferation. Defects in MS4A1 are the cause of immunodeficiency common variable type 5 (CVID5); also called antibody deficiency due to CD20 defect. CVID5 is a primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B-cells is usually in the normal range, but can be low. Belongs to the MS4A family.

Protein type: Membrane protein, integral; Cell surface; Membrane protein, multi-pass

Chromosomal Location of Human Ortholog: 11q12

Cellular Component: extracellular space; integral to plasma membrane; external side of plasma membrane

Molecular Function: epidermal growth factor receptor binding

Biological Process: B cell proliferation; humoral immune response

Disease: Immunodeficiency, Common Variable, 5