BTLA

Description

The BTLA (B and T lymphocyte associated) is a protein-coding gene located on chromosome 3.

BTLA, also known as B- and T-lymphocyte attenuator or CD272, is a protein belonging to the CD28 immunoglobulin superfamily (IgSF). It is encoded by the BTLA gene located on human chromosome 3. BTLA was identified as an inhibitor of Th1 expansion and is the third member of the CD28 IgSF. Notably, its ligand, HVEM (also known as TNFRSF14), belongs to the tumor necrosis factor receptor superfamily (TNFRSF), a surprising discovery since receptors and ligands were previously thought to always belong to the same family. BTLA is widely expressed in various organs, including lymph nodes, thymus, and spleen, where high expression is observed. In contrast, low or no expression is detected in organs like the liver, kidney, heart, brain, and others. BTLA expression is also found in specific cell populations such as T cells, B cells, DCs, and NKT cells, with expression levels fluctuating depending on developmental stages. For instance, in T cells, BTLA expression is stable in naive T cells, increases upon stimulation, and then decreases again when the T cell becomes fully activated. BTLA is a 289 amino acid long transmembrane glycoprotein.

BTLA negatively regulates antigen receptor signaling in lymphocytes via interaction with tyrosine phosphatases PTPN6/SHP-1 and PTPN11/SHP-2. BTLA can interact with TNFRSF14 in cis (on the same cell) or in trans (on other cells). Cis interactions play a regulatory role in naive T cells, inhibiting trans interactions to maintain a resting state. Conversely, trans interactions can predominate during adaptive immune responses, providing survival signals to effector T cells.

BTLA is also known as BTLA1, CD272.

Associated Diseases

WES Whole Exome Sequencing

Clinical Exome Sequencing