TOX2 [MD393R]

Thymocyte selection-associated high mobility group box protein (TOX), is a crucial 526 amino acid nuclear protein belonging to the evolutionarily conserved high-motility group (HMG)-box superfamily, which plays a significant role in T-cell development regulation. Tox also defines a small subfamily of proteins that include Tox2, Tox3, and Tox4, all of which are highly conserved in vertebrate species but have unique tissue expression patterns and functions. TOX expression is notably upregulated by pre-T cell receptor (pre-TCR) and TCR activation in immature thymocytes, but not in mature thymocytes, highlighting TOX importance in early T-cell maturation stages. This indicates that TOX-dependent transition to the CD4(+)CD8(+) stage is critical for class II major histocompatibility complex-specific T cell development. Additionally, calcineurin activation appears linked to CD8 lineage commitment, as TOX upregulation in double-positive thymocytes depends on calcineurin activity, underscoring TOX pivotal role in T-cell differentiation and immune response. This antibody recognizes endogenous levels of total Tox and Tox2 proteins, but not cross-react with Tox3 or Tox4 proteins.