ELISA Kits

Thrombopoietin(TPO) is also called megakaryocyte growth and development factor(MGDF). TPO, a lineage-specific cytokine affecting the proliferation and maturation of megakaryocytes from committed progenitor cells, is believed to be the major physiological regulator of circulating platelet levels. Human, dog, and mouse cDNAs for MGDF are highly conserved and encode open reading frames for proteins of 353, 352, and 356 amino acids, respectively, including predicted signal peptides. MGDF is a novel cytokine that regulates megakaryocyte development and is a ligand for the MPL receptor. The human MGDF gene has been mapped to chromosome 3q26.3. The standard product used in this kit is gene recombinant mouse TPO, consisting of 419 amino acids with the molecular mass of 35KDa. As a result of glycosylation, the molecular mass is 75KDa.

Tyrosine kinase with Ig and EGF homology domain 2(Tie-2), also called TEK tyrosine kinase, endothelial(TEK). Tie-2 and tie-1 are expressed in early embryonic vascular system and in maternal decidual vascular endothelial cells, where the vasculature undergoes an active angiogenesis. Tie-2, but not tie-1, expression was also detected in extraembryonic mesoderm of the amnion. Angiogenesis is coordinated with follicular cell growth in goitrogenesis. The angiopoietins, Ang-1 and Ang-2, are angiogenic growth factors acting through Tie-2. Tie-2 and Ang-1 are expressed in thyroid epithelial and endothelial cells, and Tie-2 is regulated by TSH and cAMP in follicular cells. And Tie-2 expression is increased in goiter in both humans and rats, consistent with a role in goitrogenesis. Tie2/Ang-1 signaling pathway plays a critical role in the maintenance of HSCs in a quiescent state in the BM niche. And the Tie-2 signaling pathway is also critical for endothelial cell-smooth muscle cell communicatio

The tissue inhibitor of metalloproteinases 1(TIMP1) is also called erythroid-potentiating activity(EPA). The X-linked gene for human TIMP1 is expressed in some but not all inactive X-containing somatic-cell hybrids, suggesting that this gene is either prone to reactivation or variable in its inactivation. Purified EPA specifically stimulates human and murine cells of the erythroid lineage, unlike murine interleukin-3(IL-3) which stimulates precursor cells from all haematopoietic lineages. TIMP1 is thought to play a regulatory role in connective tissues by forming inactive complexes with those metalloproteinases that are normally responsible for connective tissue turnover. The human gene encoding TIMP has been mapped to the X chromosome in the region Xp11.1-p11.4. The standard product used in this kit is natural TIMP-1 with the molecular mass of 22KDa.

TIMP metallopeptidase inhibitor 1, also known as TIMP1, a tissue inhibitor of metalloproteinases, is a glycoprotein that is expressed from the several tissues of organisms. This protein is a member of the TIMP family. It was found to reside at Xp11.4-p11.1. This is the first growth factor found to be X-linked. The glycoprotein is a natural inhibitor of the matrix metalloproteinases (MMPs), a group of peptidases involved in degradation of the extracellular matrix. In addition to its inhibitory role against most of the known MMPs, the encoded protein is able to promote cell proliferation in a wide range of cell types, and may also have an anti-apoptotic function. What’s more, TIMP1 is thought to play a regulatory role in connective tissues by forming inactive complexes with those metalloproteinases that are normally responsible for connective tissue turnover.

TIMP2 gen is encoded by 5 exons spanning 83 kb of genomic DNA. TIMP2 is 83 kilobase pairs(kb) long with exon-intron splicing sites located in preserved positions among the three members of the TIMP family. The gene for tissue inhibitor of metalloproteinases-2 is localized on human chromosome arm 17q25. TIMP-2 abrogates angiogenic factor-induced endothelial cell proliferation in vitro and angiogenesis in vivo independent of MMP inhibition. The standard product used in this kit is recombinant human TIMP-2 with the molecular mass of 22Kda and 194 amino acid.

The tissue inhibitors of metalloproteinases(TIMPs) are natural inhibitors of the matrix metalloproteinases, a group of zinc-binding endopeptidases involved in the degradation of the extracellular matrix. The TIMP3 gene is expressed in many tissues, with highest expression in the placenta. TIMP3 encodes a potent angiogenesis inhibitor and is mutated in Sorsby fundus dystrophy, a macular degenerative disease with submacular choroidal neovascularization. TIMP3 gene is mapped to 22q12.1-q13.2. Mutations in TIMP3 cause the autosomal dominant disorder Sorsby's fundus dystrophy(SFD).

Tissue inhibitor of metalloproteinases 4, also called Metalloproteinase inhibitor 4, is an enzyme that in humans is encoded by the TIMP4 gene. This gene belongs to the TIMP gene family. The proteins encoded by this gene family are inhibitors of the matrix metalloproteinases, a group of peptidases involved in degradation of the extracellular matrix. This gene is mapped to 3p25.2. The secreted, netrin domain-containing protein encoded by this gene is involved in regulation of platelet aggregation and recruitment and may play role in hormonal regulation and endometrial tissue remodeling.

Tumor necrosis factor-alpha(TNF-alpha, or TNF) is secreted by macrophages in response to inflammation, infection and cancer. Human Tumor Necrosis Factor(TNF) and Lymphotoxin(TNF-beta) are cytotoxic proteins which have similar biological activities and share 30% amino acid homology. TNF-alpha is produced by monocytes, which can stimulate endothelial cells to produce the multilineage growth factor granulocyte-macrophage colony-stimulating factor and extend the role of this immunoregulatory protein to the regulation of hematopoiesis in vitro. TNF is a soluble protein that causes damage to tumor cells but has no effect on normal cells. Human TNF has been purified to apparent homogeneity as a 17.3-kilodalton protein from HL-60 leukemia cells and has showed cytotoxic and cytostatic activities against various human tumor cell lines. The human TNF cDNA is 1585 base pairs in length and encodes a protein of 233 amino acids. The mature protein begins at residue 77, leaving a long leader sequence