You searched for: Proteins and Peptides
Proteins are used in routine laboratory procedures such as binding enzymes or coupling peptides to carrier proteins. These kits, mixture solutions, and collagen matrices fulfill a myriad of essential laboratory functions for developing relationships between proteins and other cellular components. The stimulating proteins offered have various amino acid arrangements and functions to fulfill any sample manipulation for testing purposes in any field.
Wheat Germ Agglutinin (WGA), iFluor™ 488
Supplier: STEMCELL Technologies
Fluorescent dye conjugates for staining cell membranes of gram-positive bacteria, mammalian cells, and yeast bud scars - 1000 µg.
Expand 1 Items
Wheat Germ Agglutinin (WGA), iFluor™ 555
Supplier: STEMCELL Technologies
Fluorescent dye conjugates for staining cell membranes of gram-positive bacteria, mammalian cells, and yeast bud scars - 1000 µg.
Expand 1 Items
EBV (GP350/GP340) Peptide Pool
Supplier: STEMCELL Technologies
Stimulating T cells with EBV (GP350/340) Peptide pool releases downstream cytokines and upregulates activation markers, enabling antigen-specific T cells to be detected or isolated for analysis. EBV (GP350/340) Peptide pool is a lyophilised mixture of 224 peptides from envelope glycoprotein GP350 (GP350/340) of Epstein-Barr virus (EBV; strain B95-8), and consists of 15-mer peptides with 11-amino-acid overlaps that cover amino acids 1 to 907 on GP350/340. GP350 meditates EBV attachment to B lymphocytes via binding to the cell surface receptor CR2 (also known as C3d receptor or CD21) (Nemerow et al.; Tanner et al.). Viral peptide pools are useful for a broad range of applications, including vaccine development, immunological research, and diagnostic assay development.
Expand 1 Items
Human Recombinant IL-22
Supplier: STEMCELL Technologies
Interleukin 22 (IL-22) is a class 2 α-helical cytokine that signals through the class 2 cytokine receptor and activates the JAK/STAT pathway. IL-22 is secreted by Th1, Th2, Tc22, and γδ T cells, dendritic, mast and NK cells. It stimulates expression of antimicrobial peptides from epithelial cells, thus hindering bacterial infections. Depending on the interactions with other cytokines, IL-22 can either promote inflammation or prevent tissue destruction by regulating host defense and tissue homeostasis at barrier surfaces (Sonnenberg et al.).
Expand 1 Items
Human Recombinant IGF-II
Supplier: STEMCELL Technologies
Insulin-like growth factor 2 (IGF-II) is a polypeptide that belongs to the family of insulin-like growth factors that are similar in molecular structure to proinsulin. IGF-II binding to IGF-I receptor activates a signaling cascade via the MAPK and PI3K pathways. IGF-II affects growth, differentiation, and survival of cells in a variety of tissues during embryonic development. It stimulates proliferation and migration of primary lymphatic endothelial cells, and induces lymphangiogenesis (Guvakova).
Expand 3 Items
Human Recombinant EGFR
Supplier: STEMCELL Technologies
Epidermal growth factor receptor (EGFR) is a type I transmembrane protein and receptor tyrosine kinase. EGFR has been shown to bind to some members of the EGF family ligands including EGF, amphiregulin, TGF-α, betacellulin, epiregulin, heparin-binding EGF, and neuregulin-2α. EGFR ligand binding induces homodimerization, as well as heterodimerization of EGFR with ErbB2 or with ligand-activated ErbB3 or ErbB4 (Schlessinger). Dimerization results in kinase activation, phosphorylation, and cell signaling, mediated primarily through MEK/ERF and AKT pathways (Navlonic et al.). EGFR signaling has been shown to regulate cell proliferation, differentiation, motility, and apoptosis. Elevated levels of EGFR have been correlated with carcinogenesis (Maihle et al.). Protein contains a His-residue tag at the carboxyl end of the polypeptide chain.
Expand 1 Items
Human Recombinant IL-1 beta, ACF
Supplier: STEMCELL Technologies
Interleukin 1 beta (IL-1β) is synthesised as an inactive precursor protein or pro-IL-1β. This precursor is cleaved intracellularly by Caspase 1 (IL-1β convertase) to form the active form of the protein that is later secreted (Allan et al.). IL-1β binds to IL-1 receptor and activates intracellular signaling via the MAPK or NF-kB pathway. IL-1β is released by monocytes, tissue macrophages, and dendritic cells in response to infection or injury and induces expression of acute-phase proteins. It also promotes the infiltration of inflammatory and immunocompetent cells from the circulation into the extravascular space and affected tissues, by stimulating the expression of adhesion molecules on endothelial cells. IL-1β also affects other immune cells; for example, it co-stimulates T cell functions together with antigen or mitogen. It also stimulates Th17 differentiation and B cell proliferation in an IL-6-dependent manner. This product is animal component-free.
Expand 3 Items
Human/Mouse Recombinant TGF-beta 3
Supplier: STEMCELL Technologies
Transforming growth factor (TGF) beta 3 is a member of the TGF-β superfamily and regulates diverse cellular phenotypes. TGF-beta 3 binds to serine-threonine kinase type I and II receptors and activates signal transduction through SMAD2/3 proteins, thus regulating a variety of functions, including cell proliferation, differentiation, wound healing, apoptosis, and metabolism (Massagué; McDowell et al.). TGF-beta 3 enhances glycosaminoglycan production by mesenchymal stromal cells, stimulates scar-free healing, and improves glucose tolerance and phenotypic changes in adipocyte morphology (Hall et al.; Holton et al.). TGF-beta 3 induces proliferation of posterofrontal suture-derived mesenchymal stromal cells, and stimulates expression of fibroblast growth factors 2 and 18 (James et al.).
Expand 3 Items
Human Recombinant HGF (CHO-expressed)
Supplier: STEMCELL Technologies
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.).
Expand 3 Items
Human Recombinant IP-10 (CXCL10)
Supplier: STEMCELL Technologies
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.).
Expand 1 Items
Human Recombinant IFN-alpha 2B
Supplier: STEMCELL Technologies
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.).
Expand 2 Items
Rat Recombinant M-CSF
Supplier: STEMCELL Technologies
Macrophage colony-stimulating factor (M-CSF) is a homodimeric cytokine that belongs to receptor tyrosine kinase subclass III of the receptor tyrosine kinase (RTK) family. M-CSF acts on a CSF-1 receptor tyrosine kinase, which initiates signaling cascades to support cell proliferation and differentiation (Hamilton). M-CSF is produced by endothelial cells, osteoblasts, and during pregnancy by the uterine epithelial cells (Ryan). M-CSF synergizes with other factors to support proliferation and differentiation of multipotent hematopoietic progenitor cells, and regulates proliferation and differentiation of the mononuclear phagocyte progenitor cells to monocytes and macrophages. It also supports survival, proliferation, and function of the differentiated macrophages and regulates differentiation of mononuclear phagocytes to osteoclasts (Pixley and Stanley). M-CSF plays an important role in the implantation of the embryo and early development (Makrigiannakis et al.).
Expand 1 Items
Human Recombinant BAFF
Supplier: STEMCELL Technologies
B cell activating factor (BAFF) is part of the tumor necrosis factor (TNF) superfamily and is expressed by monocytes, macrophages, dendritic cells, and neutrophils (Mackay and amp; Browning; Scapini et al.). It binds to 3 receptors: BAFF-R, TACI, and BCMA, all of which are expressed by B cells at various times in their development (Liu and amp; Davidson). BAFF-R signaling activates the NF-kB signaling pathway, and promotes B cell survival, Ig class switching, and antigen presentation (Bossen and amp; Schneider; Liu and amp; Davidson; Naradikian et al.). BAFF also has functions in other cell types: it promotes monocyte survival and activation, proinflammatory cytokine secretion, and differentiation into macrophages (Chang et al.), and co-stimulates anti-CD3-mediated activation of human T cells (Huard et al.; Mackay and amp; Leung).
Expand 2 Items
Human Recombinant VEGF-C
Supplier: STEMCELL Technologies
Vascular endothelial growth factor C (VEGF-C) is a member of the VEGF/platelet-derived growth factor (PDGF) family of proteins. VEGF-C is a potent angiogenic factor and promotes lymphangiogenesis, endothelial cell growth and survival, and can affect blood vessel permeability. VEGF-C is expressed in a range of tissues, but is not expressed in peripheral blood lymphocytes. VEGF-C forms a non-covalent, cell surface-associated, disulfide-linked homodimer that can bind and activate VEGF receptors 2 (VEGFR-2 [Flk1]) and 3 (VEGFR-3 [Flt4]). Interaction with VEGFR-2 results in physiological and intratumoral neoangiogenesis and vessel sprouting (Cao et al.; Tammela et al.), whereas interaction with VEGFR-3 is critical for lymphangiogenesis (Karkkainen et al.; Laakkonen et al.; Mäkinen et al.). Overexpression of VEGF-C in tumor cells has been shown to result in enhanced lymph flow and increased metastasis to regional lymph nodes (Hoshida et al.; Mandriota et al.; Padera et al.; Skobe et al.).
Expand 1 Items
Human Recombinant Visfatin
Supplier: STEMCELL Technologies
Use visfatin to catalyse the production of nicotinamide mononucleotide from nicotinamide (Revollo et al.). Nicotinamide mononucleotide is a precursor to nicotinamide adenine dinucleotide (NAD) that is vital to energy metabolism, cell death, and other cellular processes (Ying). Visfatin also acts as an immunomodulator by activating leukocytes and inducing the production of pro-inflammatory and anti-inflammatory cytokines (Moschen et al.), and there is evidence that visfatin can regulate insulin receptor signaling and insulin secretion (Brown et al.). Belonging to the nicotinate phosphoribosyltransferase (NAPRTase) family, Visfatin is an adipokine that is produced in adipocytes, leukocytes, and hepatocytes (Chiu et al., Garten et al., Kralisch et al.). It is active as a homodimer with each identical monomer consisting of two structural domains made up of 19 β-strands and 13 α-helices (Kim et al.). For consistency and reproducibility across your applications, visfatin from STEMCELL comes lyophilised with ≥90% purity, and is verified by LAL analysis to ensure endotoxin levels are ≤1,0 EU/μg protein.
Expand 1 Items
Human Recombinant bFGF
Supplier: STEMCELL Technologies
Basic fibroblast growth factor (bFGF) is a prototypic member of the fibroblast growth factor family. Cytokines in the FGF family possess broad mitogenic and cell survival activities (Folkman and Klagsbrun; Kimelman and Kirschner) and are involved in a variety of biological processes including cell proliferation, differentiation, survival, and apoptosis (Folkman and Klagsbrun; Klagsbrun; Rifkin and Moscatelli). bFGF has the β-trefoil structure (Ponting and Russell), binds to the four FGF receptor (FGFR) family members, and activates JAK/STAT, PI3K, ERK1/2, and other receptor tyrosine kinase (RTK) signaling pathways. It supports the maintenance of undifferentiated human embryonic stem cells (Xu et al.; Kang et al.), stimulates human embryonic stem cells to form neural rosettes (Zhang et al.), and improves proliferation of human mesenchymal stem cells and enhances chondrogenic differentiation (Solchaga et al.).
Expand 3 Items
Human Recombinant FGFacidic, ACF
Supplier: STEMCELL Technologies
Fibroblast growth factor acidic (FGF-acidic), also known as FGF-1, is a potent activator of DNA synthesis, cell proliferation, and chemotaxis and is known to play numerous roles in development, regeneration, and angiogenesis (Galzie et al.; Jaye et al.; Presta et al.). FGF-acidic is produced by multiple cell types and is capable of activating all cells of mesodermal origin and many cells of neuroectodermal, ectodermal, and endodermal origin. It is found in large quantities in the brain, but is also expressed in hepatocytes, vascular smooth muscle cells, neurons of the central nervous system, skeletal muscle cells, fibroblasts, keratinocytes, endothelial cells, intestinal columnar epithelial cells, and pituitary basophils and acidophils. FGF-acidic is secreted as a disulfide-linked homodimer and is stored in complex with heparan sulfate, a requirement for its interaction with FGF receptors (Guerrini et al.; Mohammadi et al.). Internalized FGF-acidic signals via protein kinase C and promotes cell survival by inhibiting p53 and proapoptotic signaling (Bouleau et al.). This product is animal component-free.
Expand 2 Items
Human Recombinant IL-21
Supplier: STEMCELL Technologies
Interleukin 21 (IL-21) is a pleiotropic cytokine that is composed of four α-helical bundles and primarily produced by natural killer T (NKT) cells, T follicular helper (Tfh) cells, and Th17 cells (Spolski and Leonard 2008). IL-21 signals via heterodimers of the IL-21 receptor (IL-21R) and the IL2RG encoded common cytokine receptor γ-chain (Parrish-Novak et al.; Ozaki K et al. 2000), and utilizes the JAK/STAT, MAPK, and PI3K pathways (Spolski and Leonard 2014). IL-21 has been shown to have a critical role in regulating immunoglobulin production and differentiation of the pro-inflammatory Th17 population of cells (Ozaki et al. 2002; Nurieva et al.). Additionally, IL-21 specifically sustains CD8+ T cell effector activity and provides a mechanism of CD4+ T cell help during chronic viral infection (Elsaesser et al.). IL-21 signaling was also found critical for the development of type 1 diabetes in NOD mice (Sutherland et al.) and control of T cell autoimmunity by regulatory B cells (Yoshizaki et al.).
Expand 4 Items
Human Recombinant IL-21, ACF
Supplier: STEMCELL Technologies
Interleukin 21 (IL-21) is a pleiotropic cytokine that is composed of four α-helical bundles and primarily produced by natural killer T (NKT) cells, T follicular helper (Tfh) cells, and Th17 cells (Spolski and Leonard 2008). IL-21 signals via heterodimers of the IL-21 receptor (IL-21R) and the IL2RG-encoded common cytokine receptor γ-chain (Parrish-Novak et al.; Ozaki K et al. 2000), and utilizes the JAK/STAT, MAPK, and PI3K pathways (Spolski and Leonard 2014). IL-21 has been shown to have a critical role in regulating immunoglobulin production and differentiation of the pro-inflammatory Th17 population of cells (Ozaki et al. 2002; Nurieva et al.). Additionally, IL-21 specifically sustains CD8+ T cell effector activity and provides a mechanism of CD4+ T cell help during chronic viral infection (Elsaesser et al.). IL-21 signaling was also found critical for the development of type 1 diabetes in NOD mice (Sutherland et al.) and control of T cell autoimmunity by regulatory B cells (Yoshizaki et al.). This product is animal component-free.
Expand 3 Items
Lipopolysaccharide from E. coli (O55:B5)
Supplier: STEMCELL Technologies
Trigger a variety of immunological responses with E. coli Lipopolysaccharide O55:B5 (S-form), a lipopolysaccharide (LPS) derived from the O55:B5 serotype of the Gram-negative bacteria and nbsp Escherichia coli. Composed of a lipid A, a core oligosaccharide, and an O antigen, LPS are glycolipid constituents that reside on the outer membranes of gram-negative bacteria (Kitchens RL et al.). LPS protects bacteria against bile salts and lipophilic antibiotics by maintaining the outer integrity of the cell membrane (Bäckhed F et al.). E. coli lipopolysaccharide O55:B5 (S-form), in particular, is predominantly recognized by toll-like receptor 4 (TLR4), which leads to the activation of NF-κβ, a protein complex which plays a key role in regulating immune response (Kuzmich N et al.). Activation of NF-κβ can trigger increased production of pro-inflammatory cytokines IL-1 and TNF-α by macrophages (Matuschak GM et al.). This LPS can also interact with CD14 to activate phospholipase Cγ2 and kinases of the Src family, trigger influxes of extracellular Ca2+, as well as calcineurin-dependent translocation of the nuclear factor of activated T cells (NFAT) family of transcription factors (Li CC et al.). When added to ImmunoCult™-SF macrophage medium (Catalog #10961), stimulation with lipopolysaccharide from E. coli (O55:B5) and IFN-γ supports the polarization to M1 (classically activated) macrophages. Warning: This product is highly pyrogenic. Avoid all means by which the product may enter the bloodstream.
Expand 1 Items
Mouse Recombinant M-CSF (E.coli-expressed)
Supplier: STEMCELL Technologies
Macrophage colony-stimulating factor (M-CSF) is a homodimeric glycoprotein growth factor that regulates proliferation and differentiation of myeloid hematopoietic progenitors to mononuclear phagocytic cell lineages, including monocytes, macrophages, and osteoclasts. M-CSF is a crucial factor for the development of tissue-resident macrophages in most tissues (Ginhoux andamp; Jung). It is required for the maturation and activation of monocytes and macrophages, and regulates inflammatory responses in conjunction with other stimuli such as IFN-γ, LPS, and IL-4 (Murray et al.). M-CSF is also required for bone resorption by osteoclasts, and is involved in the development and regulation of placenta, mammary gland, and brain. M-CSF is produced by monocytes, fibroblasts, osteoclasts, stromal cells, endothelial cells, and tumor cells (Chockalingam andamp; Ghosh). M-CSF exerts its biological effects by signaling through a receptor tyrosine kinase (CSF-1R or M-CSF-R) encoded by the c-fms proto-oncogene (Hamilton). CSF-1R shares similar structural features with other growth factor receptors, including the stem cell factor (SCF) receptor, platelet-derived growth factor receptor (PDGF-R), and Flt3/Flk-2 receptor tyrosine kinase. Stimulation of the CSF-1R upon binding to M-CSF activates MAPK, PI3K, and PLCγ signaling pathways (Chockalingam andamp; Ghosh). Human and mouse M-CSF sequences are highly conserved both at nucleotide and amino acid levels (80% homology; DeLamarter et al.).
Expand 3 Items
Mouse Recombinant SCF (E. coli-expressed)
Supplier: STEMCELL Technologies
Stem cell factor (SCF) is an early-acting cytokine that plays a pivotal role in the regulation of embryonic and adult hematopoiesis. SCF promotes cell survival, proliferation, differentiation, adhesion, and functional activation of cells at multiple levels of the hematopoietic hierarchy. Together with other cytokines such as thrombopoietin and Flt3/Flk-2 Ligand, SCF is commonly used to promote expansion of primitive hematopoietic stem cells and multi-potent progenitor cells in culture (Huang et al.; Kent et al.). In synergy with various growth factors, including IL-2, IL-3, IL-6, IL-7, G-CSF, and erythropoietin, SCF increases proliferation and differentiation of myeloid and erythroid progenitor cells and a subset of lymphoid progenitor cells (Broudy). In the mouse, SCF is essential during fetal gonadal development (Mauduit). It is produced by stromal cells in the fetal liver, bone marrow, and thymus, in the central nervous system, in keratinocytes, and in the gut mucosa, and can function as a chemotactic and chemokinetic factor. SCF exists in two biologically active splice forms: a soluble and a transmembrane isoform. Upon binding to its receptor (c-kit tyrosine kinase receptor; CD117), it activates PI3K, JAK/STAT, and MAPK pathways. SCF and signaling from c-kit has also been reported to play an important role in pigmentation, fertility, vasculogenesis, motility of the gut via c-kit-positive interstitial cells of Cajal, and in the migration of neuronal stem and progenitor cells to sites of injury in the brain (Lennartsson and Ronnstrand).