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GRO (growth-regulated oncogene)-beta or CXCL2 is a member of the CXC family, which plays an integral role in recruitment and activation of neutrophils and basophils in response to tissue injury and microbial infection. GRO-beta and GRO-gamma are closely related to GRO-alpha and share 90% and 86% amino acid sequence homology, respectively, with GRO-alpha. Receptor-binding studies have demonstrated that GRO-alpha, -beta, and -gamma signal mainly through G protein-coupled receptors CXCR1 and CXCR2 (Ahuja and Murphy). GRO-beta is expressed in epithelial cells, monocytes, fibroblasts, and melanocytes and is further induced during inflammatory, epithelialization, and angiogenic processes, for example during the wound healing process of human burn wounds (Zaja-Milatovic and Richmond). GRO-beta also stimulates mitogenesis in certain human melanoma cells (Unemori et al.).

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Hepatocyte growth factor/scatter factor (HGF/SF) is a pleiotropic growth factor that promotes proliferation, motility, survival, and differentiation. HGF binds and promotes the dimerization and activation of the receptor tyrosine kinase c-MET, and stimulates PI3K/AKT, FAK, JNK, and ERK1/2 signaling (Organ and Tsao). HGF stimulates migration of cells during embryogenesis, induces cell motility and scattering of epithelial cells, and regulates epithelial-mesenchymal transition. It is a chemoattractant for motor neurons, and regulates the development of sensory, sympathetic, parasympathetic, and cortical neurons as well as the proliferation of oligodendrocytes and glial development. Additionally, HGF is cytoprotective and regulates liver growth and regeneration (Nakamura et al.).

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Interleukin 2 (IL-2) is a monomeric cytokine that was originally identified as a T cell growth factor (Gaffen and Liu). It binds to a heterotrimeric receptor consisting of CD25, CD122, and CD132. Upon binding, it activates JAK3-, STAT5-, and AKT-dependent signaling pathways, which results in cellular proliferation and survival (Ma et al.). The majority of IL-2 is secreted by activated CD4+ and CD8+ T cells, although B cells and dendritic cells were found to produce IL-2 in small amounts. IL-2 downregulates immune responses to prevent autoimmunity during thymic development, influences the development of CD4+CD25+ regulatory T cells, and affects development of follicular helper T cells. IL-2 also controls inflammation by inhibiting Th17 differentiation (Banchereau et al.). Targeted deletions of the IL-2 gene in mice resulted in development of autoimmune hemolytic anemia, followed by ulcerative colitis. Similar effects were observed in mice that were deficient in IL-2 receptor α (Gaffen and Liu).

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Interferon gamma-inducible protein (IP) 10 or CXCL10 is a member of the CXC chemokine family. It binds CXCR3 activating ERK1/2, p38/MAPK, JNK, and PI3-kinase/AKT signaling pathways, inducing intracellular calcium influx, DNA synthesis, cell proliferation, and chemotaxis. IP-10 regulates innate and adaptive immune responses by affecting the function of activated T cells, natural killer cells, inflammatory dendritic cells, macrophages, and B cells. IP-10 is produced by leukocytes, activated neutrophils, eosinophils, monocytes, epithelial cells, endothelial cells, fibroblasts, and keratinocytes in response to IFN-gamma. IP-10 has been implicated in a wide range of diseases, including infectious diseases and chronic inflammatory and autoimmune diseases, as well as in tumor formation (Liu et al.).

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Fibroblast growth factor 18 (FGF-18) is a growth factor and member of the FGF subfamily. FGF-18 is most similar to FGF-8 and FGF-17, and is secreted in adult lung and developing tissues (Ohbayashi et al.). FGF-18 signals through FGF receptor 3 (FGFR3) to regulate proliferation, differentiation, and matrix production of articular and growth plate chondrocytes in vivo and in vitro (Davidson et al.). FGF-18 has skeletal functions and protects articular cartilage by gene expression profiling and regulates proliferation and differentiation of midline cerebellar structures (Mori et al.). Also, recombinant human FGF-18 has been shown to effectively regulate hair growth (Song et al.).

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Human Recombinant Angiotensin-Converting Enzyme 2 (ACE2) Protein, aa18-740, is expressed in HEK293 cells. ACE2 activity results in vasodilation by degrading vasoconstrictor angiotensin II to produce vasodilator angiotensin. Decreased expression of this enzyme is associated with cardiovascular disease and possibly also glomerular injury in diabetic nephropathy. ACE2 contains a peptidase domain at the N-terminus and a single transmembrane helix. ACE2 is also the primary human receptor for the surface spike glycoprotein of SARS-CoV-2 and SARS-CoV. This receptor is expressed in human lung and small intestine epithelia as well as the heart, kidney, and testes. The peptidase domain of ACE2 binds to the protein-binding domain of the S1 protein subunit of the spike protein; this binding results in a cleavage site becoming exposed. Cleavage, or ‘protein priming’, is done by TMPRSS2, a cellular serine protease, and by cathepsins. This cleavage activates the S2 subunit of the spike protein, allowing the fusion of the viral membrane to the host cell membrane. At the carboxy terminus, Human Recombinant ACE2 Protein contains a TEV site and a human IgG1 Fc tag.

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Tumor necrosis factor-α (TNF-α) is a pro-inflammatory cytokine that activates NF-κB, MAPK, and PI3K/AKT pathways. Activated T cells and macrophages are the primary producers of TNF-α in response to inflammation and infectious conditions. Many other cell types have been shown to produce TNF-α, among them B cells, NK cells, mast cells, neutrophils, dendritic cells, microglia, endothelial cells, smooth muscle cells, cardiomyocytes, and fibroblasts. TNF-α has cytotoxic effects on cancer cells in vitro by stimulating anti-tumor immunosuppressive responses. TNF-α stimulates expression of E- and P-selectins, thus facilitating adhesion of neutrophils, monocytes, and memory T cells to activated platelets and endothelial cells (Zelová andamp; Hosek). Other effects of TNF-α include vasodilatation and edema formation.

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Interleukin 1 alpha (IL-1α) is a member of the IL-1 family and a dual-function cytokine. Both the unprocessed precursor and a processed IL-1α protein signal through IL-1 receptor type 1 (IL-1R1). Various cells, including keratinocytes, thymic epithelium, hepatocytes, endothelial cells, fibroblasts, and the epithelial cells of mucous membranes, have high levels of intracellular IL-1α precursor. The precursor is also expressed on the surface of monocytes and B lymphocytes (Netea et al.). IL-1α recruits infiltrating cells to a site of injury during necrosis and plays an important role during processes of sterile inflammation (Cohen et al.; Rider et al.). During hypoxia, IL-1α contributes to angiogenesis (Carmi et al.). Studies in mice show that IL-1α is produced by microglia-like cells after ischemic brain injury, which contributes to the inflammation (Luheshi et al.).

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Conveniently and consistently add transforming growth factor beta 1 (TGF-ꞵ1) to your cultures with this cell culture-ready formulation. This human recombinant TGF-ꞵ1 is precisely reconstituted to 0,1 mg/ml in 100 mM acetic acid and requires no additional preparation, improving reproducibility. Endotoxin levels are verified, using the LAL method to ensure consistency for use across multiple applications. A member of the TGF-β superfamily, TGF-β1 regulates diverse cellular phenotypes. TGF-β1 binds to serine-threonine kinase type I and II receptors and activates signal transduction through SMAD2/3 proteins.

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Neurotrophin-3 (NT-3) is a neurotrophic factor and a member of the nerve growth factor (NGF) family of proteins that includes neuron growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-4/5. NT-3 signals a number of trophic effects through its transducing receptor tyrosine kinase TrkC. NT-3 is known to promote survival, development, and differentiation of neurons, and modulates transmitter release at several types of synapses in the peripheral and central nervous systems (Chalazonitis 1996). NT-3 has been shown to have an important role in the overall development of enteric neurons, which are crucial for gut peristalsis (Chalazonitis 2004). Studies in rats have shown the potential of NT-3 in dorsal column axonal regeneration (Bradbury et al.). NT-3 was shown to protect neurons against amyloid-β toxicity (Lesne et al.). NT-3 has applications in neuronal differentiation protocols to generate β-tubulin III+ peripheral neurons from neural crest stem cells (Menendez et al.) and oligodendrocyte precursor cells from human embryonic stem (ES) and induced pluripotent stem (iPS) cells (Douvaras et al.).

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Use angiopoietin-like protein 2 (ANGPTL2) to regulate tissue remodeling through integrin α5β signaling and activation of p38 mitogen-activated protein kinases (MAPK) (Odagiri et al.; Tabata et al.). Highly expressed in the heart, small intestine, and stomach, ANGPTL2 is a glycosylated secretory protein that contains a coiled domain and a fibrinogen-like domain (Kim et al.). Studies have shown that the coiled-coil domain of ANGPTL2 functions as a growth factor, enhancing the survival of hematopoietic stem cells (HSCs) ex vivo (Broxmeyer et al.). ANGPTL2 is also known to play a role in obesity and metabolic diseases, promoting local inflammation in adipose tissue and systemic insulin resistance in mice models (Tabata et al.). By activating an inflammatory cascade in endothelial cells and increasing macrophage infiltration, ANGPTL2 accelerates vascular inflammation which may lead to endothelial dysfunction and atherosclerosis progression (Horio et al.). This protein product contains a His-residue tag at the amino end of the polypeptide chain. For consistency and reproducibility across your applications, sclerostin from STEMCELL comes lyophilised with ≥92% purity, and endotoxin levels are verified to be ≤1.0 EU/μg protein.

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Epidermal growth factor (EGF) is the founding member of the EGF family of proteins and is characterized by high affinity binding to various EGF receptors (EGFRs) and the production of mitogenic responses (Carpenter and Cohen). EGF promotes EGFR dimerization, resulting in activation of downstream pathways including PI3K, ERK1/2, JAK/STAT, β-catenin, and calcium signaling. EGF is secreted by the gut-associated salivary and Brunner’s glands, is found in a variety of body fluids, and stimulates cell proliferation and differentiation in rodent and neonatal human intestine (Wright et al.). EGF can stimulate the proliferation of mouse embryonic stem cells or induce the terminal differentiation/growth inhibition of A431 cells (Heo et al.).

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Commonly known as vaspin, Serpin A12 is an adipokine that is thought to perform insulin-sensitizing functions, such as the regulation of kallikrein 7 (KLK7), an insulin-inhibiting protease (Heiker et al.). The Serpin A12 glycoprotein belongs to the serine protease inhibitor family (serpin), and is mainly associated with obesity, insulin resistance, and glucose metabolism, but may also protect against high fat-induced bone loss (Wang et al.). Serpins share a highly conserved core structure with multiple α-helices, β-strands, and a reactive site loop (RCL) to interact with the target protease (Huntington). It is expressed predominantly in visceral adipose tissue and at significantly higher amounts in obese individuals (Kurowska et al.). This protein contains a His-residue tag at the carboxyl end of the polypeptide chain. For consistency and reproducibility across your applications, Serpin A12 from STEMCELL comes lyophilised with ≥94% purity, and is verified by LAL analysis to ensure endotoxin levels are ≤1,0 EU/μg protein.

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Oncostatin M (OSM) is a member of interleukin 6 (IL-6) family of cytokines and bears close resemblance to leukemia inhibitory factor (LIF) and granulocyte colony-stimulating factor (G-CSF) in amino acid sequence and its modulation of differentiation in a variety of cell types (Rose and Bruce). OSM signals through type I receptor (consisting of gp130 and LIF receptor [LIFR]) and type II receptor (consisting of gp130 and OSM receptor [OSMR]), which eventually activate the JAK/STAT pathway (Auguste et al.; Gómez-Lechón). OSM is primarily produced by activated T cells and monocytes, and also by activated macrophages, neutrophils, mast cells, and dendritic cells. OSM is also produced within the bone microenvironment by cells of both hematopoietic and mesenchymal origin, including osteocytes and osteoblasts. OSM is involved in differentiation, cell proliferation, hematopoiesis, and inflammation, and also has been shown to have implications in liver development and bone formation and resorption (Sims and Quinn; Tanaka and Miyajima). This product is animal component-free.

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Insulin-like growth factor-binding protein 4 (IGFBP-4) inhibits the actions of IGF-I and IGF-II. The distribution of IGFBP-4 in tissues is dependent on its glycosylation state, however it preferentially targets connective tissue (Firth and Baxter; Qin et al.). IGFBP-4 is also produced in liver, adrenal glands, Leydig cells, developing embryos, spinal cord, and thymic cortex. IGFBP-4 inhibits WNT/β-catenin signaling, which downregulates prostate cancer proliferation (Zhu et al.). In vitro studies suggest that IGFBP-4 inhibits proliferation of neuroblastoma and glioma, while promoting bone loss in osteosarcoma and multiple myeloma (Durai et al.).

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Sonic hedgehog (Shh) is a member of the Hedgehog family of secreted signaling proteins that has a prominent role in patterning during early mammalian development (Ho and Scott). It is expressed during early embryogenesis in a variety of tissues (Finco et al.). During patterning of the central nervous system, Shh directly acts on cells to specify neural cell fates, regulates proliferation and survival of oligodendrocytes precursors and neural crest cells and stimulates proliferation, differentiation and axon growth (Ho and Scott; Martí). Shh also regulates T cell differentiation and activation (Crompton et al.). Recombinant human Shh (C24II; rhShh) is a fully biologically active molecule.

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Interleukin 33 (IL-33) is a pro-inflammatory cytokine from the IL-1 family. It binds to ST2 receptor and activates NF-κB and MAPK pathways. IL-33 is expressed by epithelial cells, smooth muscle cells, and fibroblasts in various tissues and organs, as well as resting basophils, mast cells, eosinophils, natural helper cells, group 2 innate lymphoid cells, dendritic cells, and activated macrophages (Schmitz et al.; Yasuda et al.). It contributes to allergic inflammation by stimulating production of the cytokines IL-4, IL-5, and IL-13, and stimulates host defense against microbial and viral infections (Liew; Yasuda et al.). In the central nervous system, IL-33 is produced by endothelial cells and astrocytes. It induces proliferation of microglia and mediates production of pro-inflammatory cytokines (Yasuoka et al.).

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Interferon-alpha (IFN-α) is a type I interferon, produced by virus infected cells, and is released as a soluble factor to initiate antiviral responses (Isaacs and Lindenmann). IFN-α2 is the most potent IFN-α used in fundamental research and in most clinical applications. The best known IFN-α2 subvariants, 2A and 2B, differ by only one or two amino acids at positions 23 and/or 34 of the mature protein (von Gabain et al.). Type I IFNs exert potent antitumor activity by increasing the cytotoxic activity of NK and T cells, as well as inhibiting the proliferation of cancer cells (Paul et al.). Additionally, it has been shown that proinflammatory IFN-α modulates the function of B cells in patients with systemic lupus erythematosus (Chang et al.) and pegylated form of IFN-α 2A and 2B has implications in the treatment of Hepatitis C (Foster et al.).

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Interleukin 6 (IL-6) is a pleiotropic growth factor with the wide range of biological activities in immune regulation, hematopoiesis, and oncogenesis. IL-6 is produced by a variety of cell types including T cells, B cells, monocytes and macrophages, fibroblasts, hepatocytes, vascular endothelial cells, and various tumor cell lines. On its own or in combination with other factors such as IL-2 and interferon-γ, IL-6 stimulates the proliferation of B cells, T cells, and hybridoma cells (Hirano et al.; Mihara et al.; Tanaka et al). In combination with cytokines such as IL-3, GM-CSF and SCF, IL-6 has been shown to promote hematopoietic progenitor cell proliferation and differentiation in vitro. IL-6 signals through a cell surface type I cytokine receptor complex consisting of the ligand-binding IL-6α (CD126) and the signal-transducing gp130 subunits. The binding of IL-6 to its receptor system includes activation of JAK/STAT signaling pathway (Mihara et al.; Peters et al.; Tanaka et al.).

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Interleukin 2 (IL-2) is a monomeric cytokine that was originally identified as a T cell growth factor (Gaffen and Liu). It binds to heterotrimeric receptors consisting of CD25, CD122, and CD132. Upon binding, it activates JAK3-, STAT5-, and AKT-dependent signaling pathways, which results in cellular proliferation and survival (Ma et al.). The majority of IL-2 is secreted by activated CD4+ and CD8+ T cells, although B cells and dendritic cells were found to produce IL-2 in small amounts. IL-2 downregulates immune responses to prevent autoimmunity during thymic development, influences the development of CD4+CD25+ regulatory T cells, and affects development of follicular helper T cells. IL-2 also controls inflammation by inhibiting Th17 differentiation (Banchereau et al.). High IL-2 levels in serum are associated with progression of scleroderma, rheumatoid arthritis, and gastric and non-small cell lung cancer, though no known disease can be directly attributed to the lack or excess of IL-2 (Gaffen and Liu).

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Use Interferon beta (IFN-β) to modulate the activity of genes that control dendritic cell activation, T cell survival, NK cell activation, chemokine expression, lymph node retention, and antiproliferative and antiviral effects (Dunn et al. Nat Rev Immunol, 2006). IFN-β binds to a receptor complex composed of IFNAR1 and IFNAR2, and initiates signal transduction via the JAK/STAT pathway. It is predominantly produced by fibroblasts, with smaller amounts from plasmocytoid dendritic cells. Macrophages and endothelial cells secrete IFN-β in response to viral infection (Reder and Feng. Front Immunol, 2013). IFN-β suppresses Th17 cells by affecting expression of IL-4, IL-10, and IL-27, and is a first-line treatment for multiple sclerosis. IFN-β was also shown to expand regulatory T cells and limit T cell trafficking to the central nervous system (Inoue and Shinohara. Immunology, 2013). Of the two IFN-β variants (IFN-β1 and IFN-β3), this product is the IFN-β1 form.

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Interleukin 15 (IL-15) is a four-alpha helix bundle cytokine with many similar properties to IL-2, with which it shares components of its receptor. The IL-15 receptor is a heterotrimeric receptor composed of IL-15Ra, the high-affinity receptor for IL-15, as well as IL-2/15Rb (CD122) and common gamma chain (CD132). IL-15 binds to IL-15Rα receptor and can then be presented in trans to IL-2/15Rb and common gamma chain on other cells. Trans-presentation is thought to be the major mechanism by which IL-15-mediated responses occur in mice, although may not be necessary in humans (Castillo et al.). The cytoplasmic domains of IL-2/15Rb and common gamma chain mediate signaling to activate JAK/STAT and PI3K pathways. IL-15 supports the survival and proliferation of naive CD4+ and CD8+ T cells, and promotes homeostasis of memory T cells. IL-15 also promotes the survival and differentiation of NK cells and regulates their cytolytic activity (Ma et al.).

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Adipocyte-specific adhesion molecule (ASAM) may play a role in cell-cell adhesion as it is expressed in epithelial cells of various tissues and is associated with tight junctions (Raschberger et al., Sze et al.). This type 1 transmembrane protein belongs to the cortical thymocyte marker in the Xenopus (CTX) family within the immunoglobulin superfamily. Sequence alignment analysis has shown that ASAM shares conserved characteristics with other CTX-like proteins, including extracellular V-type and C2-type domains, a transmembrane region, and a cytoplasmic tail (Raschperger et al.). ASAM is also expressed in adipocytes, and was found to be upregulated in white adipose tissue (WAT) in a rodent model of obesity and type II diabetes (Eguchi et al.). This protein contains a His-residue tag at the carboxyl end of the polypeptide chain. For consistency and reproducibility across your applications, adipocyte-specific adhesion molecule from STEMCELL comes lyophilised with ≥94% purity, and is verified by LAL analysis to ensure endotoxin levels are ≤1,0 EU/μg protein.

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Fibroblast growth factor (FGF) 9 is a pleiotropic member of the FGF family. FGFs are heparin-dependent regulators of cell proliferation and differentiation (Itoh and Ornitz). FGF-9 signals by binding FGFR3 (IIIb) and the IIIc splice variants of the FGFR1, FGFR2, and FGFR3 receptors (Santos-Ocampo et al.; Mohammadi et al.; Plotnikov et al.). In mice, deletion of FGF-9 is lethal and expression of FGF-9 affects development of the skeleton, cerebellum, lungs, heart, vascular system, digestive tract, and testes (Colvin et al.; Harada et al.; Lin et al.). Altered levels of FGF-9 have also been reported in various types of human cancers (Leushacke et al.; Abdel-Rahman et al.).

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Human Interleukin 4 (IL-4) is important for immune responses to helminth infection as well as in allergic responses (Olpihant et al.). The IL-4 receptor consists of a heterodimer of IL-4Ra and common gamma chain. IL-4 receptor engagement leads to the activation of JAK1/3 and the recruitment of STAT6 and IRS1/2 (Nelms et al.). IL-4 drives immunoglobulin class switching in B cells (to IgE, IgG4), mast cell hyperplasia, mucus production, and the differentiation of naïve T cells into Th2 cells, which produce IL-4, IL-5, IL-10, and IL-13 (Bao et al.; Nelms et al.; Olpihant et al.). In addition to Th2 cells, IL-4 is produced by CD4+ NK T cells, γ/δ T cells, activated basophils, eosinophils, and mast cells. Human IL-4 does not cross-react with mouse cells (Park et al.).

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Interleukin 12 (IL-12p70) is a heterodimeric cytokine composed of p35 and p40 subunits. IL-12 is produced by monocytes, macrophages, dendritic cells, neutrophils and B cells in response to bacterial products and cytokines such as IFN-γ. The IL-12 receptor is expressed on T, NK, and dendritic cells. Upon binding, IL-12 initiates signaling via the JAK/STAT signaling pathway and stimulates NK, B, and T cells to produce IFN-γ (Watford et al.). It also regulates cytokine synthesis, proliferation of T and NK cells, and stimulates differentiation of CD4+ and CD8+ T cells (Germann and Rüde). Mice that are deficient in IL-12 are susceptible to many intracellular pathogens and have impaired IFN-γ secretion, Th1 differentiation and NK cytolytic activity; however, Th2 development and IL-4 production are enhanced (Watford et al.).

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Epidermal growth factor (EGF) is characterized by high-affinity binding to various EGF receptors (EGFRs) and the production of mitogenic responses (Carpenter and Cohen). EGF promotes EGFR dimerization, resulting in activation of downstream pathways including PI3K, ERK1/2, JAK/STAT, β-catenin, and calcium signaling. EGF is secreted by the gut-associated salivary and Brunner’s glands, is found in a variety of body fluids, and stimulates cell proliferation and differentiation in rodent and neonatal human intestine (Wright et al.). Central nervous system stem cells also proliferate in response to the EGF stimulus (Reynolds and Weiss). This product is animal component-free.

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Vascular endothelial growth factor (VEGF-165) is a heparin-binding homodimeric glycoprotein involved in embryonic vasculogenesis and angiogenesis. VEGF binds to VEGFR-1 (R1) and VEGFR-2 (R2), and activates Raf/MEK/ERK and PI3K/AKT pathways (Ferrara et al.). It plays an important role in neurogenesis both in vitro and in vivo (Storkebaum et al.). It has neurotrophic effects on neurons of the central nervous system and promotes growth and survival of dopaminergic neurons and astrocytes. VEGF also promotes growth and survival of vascular endothelial cells, monocyte chemotaxis, and colony formation by granulocyte-macrophage progenitor cells (Ferrara et al.).

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Interleukin 4 (IL-4) is a type I cytokine produced by Th2 T cells, NK T cells, γ/δ T cells, eosinophils, mast cells, and activated basophils. IL-4 receptors are present on a number of cells, including hematopoietic, endothelial, epithelial, muscle, and brain tissues. IL-4 receptor engagement initiates signaling through the JAK/STAT pathway, and leads to the activation of PI3K and Ras/MAPK pathways (Nelms et al.). IL-4 plays a key role in immunoglobulin class switching in B cells and in regulating the differentiation of naïve T cells into T helper 2 (Th2) cells, while inhibiting Th1 differentiation. IL-4 acts together with tumor necrosis factor to stimulate expression of adhesion molecules on vascular endothelial cells and to downregulate expression of E-selectin, thus recruiting T cells and eosinophils to the site of inflammation (Nelms et al.).

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Thrombopoietin (TPO) is a key regulator of megakaryocytopoiesis and thrombopoiesis in vitro and in vivo. TPO stimulates the proliferation and maturation of megakaryocytes and has an important role in regulating the level of circulating platelets in vivo. TPO also promotes the survival, self-renewal, and expansion of hematopoietic stem cells and primitive multilineage progenitor cells. It is commonly used with other cytokines such as stem cell factor (SCF) and Flt3/Flk-2 Ligand to promote expansion of primitive hematopoietic cells in culture (Hitchcock andamp; Kaushansky). The TPO receptor, c-Mpl, is expressed at all stages of megakaryopoiesis, from hematopoietic stem and progenitor cells to mature platelets.