Anti-Thyroxine Binding Globulin/SERPINA7 Antibody Picoband® Fluoro488 Conjugated

Thyroxine-binding globulin (TBG) is a globulin protein that in humans is encoded by the SERPINA7 gene. There are three proteins including thyroxine-binding globulin (TBG), transthyretin and albumin responsible for carrying the thyroid hormones thyroxine (T4) and 3,5,3'-triiodothyronine (T3) in the bloodstream. This gene encodes the major thyroid hormone transport protein, TBG, in serum. It belongs to the serpin family in genomics, but the protein has no inhibitory function like many other members of the serpin family. Mutations in this gene result in TGB deficiency, which has been classified as partial deficiency, complete deficiency, and excess, based on the level of serum TBG. Alternatively spliced transcript variants encoding different isoforms have been found, but the full-length nature of these variants has not been determined.

Part of the TCR-CD3 complex present on T-lymphocyte cell surface that plays an essential role in adaptive immune response. When antigen presenting cells (APCs) activate T-cell receptor (TCR), TCR-mediated signals are transmitted across the cell membrane by the CD3 chains CD3D, CD3E, CD3G and CD3Z. All CD3 chains contain immunoreceptor tyrosine-based activation motifs (ITAMs) in their cytoplasmic domain. Upon TCR engagement, these motifs become phosphorylated by Src family protein tyrosine kinases LCK and FYN, resulting in the activation of downstream signaling pathways. In addition of this role of signal transduction in T-cell activation, CD3E plays an essential role in correct T-cell development (PubMed:19956738, PubMed:24899501) . Participates also in internalization and cell surface down-regulation of TCR-CD3 complexes via endocytosis sequences present in CD3E cytosolic region.

1. Bertenshaw, R., Takeda, K., Refetoff, S. Sequencing of the variant thyroxine-binding globulin (TBG) -Quebec reveals two nucleotide substitutions. Am. J. Hum. Genet. 48: 741-744, 1991. 2. Buchanan, B. D., Hagen, G. A. Elevated thyroxine-binding globulin with X chromosome linked inheritance. Clin. Endocr. 11: 665-669, 1979. 3. Burr, W. A., Ramsden, D. B., Hoffenberg, R. Hereditary abnormalities of thyroxine-binding globulin concentration: a study of 19 kindreds with inherited increase or decrease of thyroxine-binding globulin. Quart. J. Med. 49: 295-313, 1980.

Alpha-beta T cell receptor complex; external side of plasma membrane; immunological synapse; cell body; cell-cell junction; dendritic spine; integral component of membrane