Anti-thymosin beta 4, X-linked antibodies enable researchers to detect and measure the thymosin beta 4, X-linked antigen in biological samples. This target is a reported synonym of the TMSB4X gene, which encodes thymosin beta 4 X-linked. This protein is known to function in the regulation of cell differentiation, among other biological roles. The human version of thymosin beta 4, X-linked has a canonical amino acid length of 44 residues and a protein mass of 5.1 kilodaltons. It is reported to be localized in the cytoplasm of cells and notably expressed in many tissues, such as the bone marrow, urinary bladder, and appendix. thymosin beta 4, X-linked is a member of the Thymosin beta protein family.