You searched for: Proteins and Peptides

Supplier: Anaspec

The recombinant human Sirtuin 1 (GenBank Accession #: NM_012238) with 193- 741 amino acids and GST tag at its N-terminal was expressed in E. coli. The molecular mass of the enzyme is approximately 87.2 kDa on SDS-PAGE.
Sirtuins comprise a unique class of nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases (class III HDACs) targeting multiple protein substrates.
Sirtuin 1 (SIRT1), the human homolog of yeast Sir2 (Silent Information Regulator 2), is the most studied of the seven members of sirtuin family. SIRT1 have been implicated in several important cellular processes, including genomic stability and DNA repair, p53-mediated apoptosis, adipogenesis, and aging.
Substrates for SIRT2 are not limited to histones but also include various transcription factors and co-regulators that modulate metabolic, cell cycle and cell death related pathways. Human SIRT2 is a cytoplasmic protein that increases in abundance during mitosis and regulates major events of cytokinesis.

Supplier: BioVendor

Lipoprotein lipase (LPL) is the central enzyme in plasma triglyceride hydrolysis and is secreted by macrophages in the subendothelial space. Evidence has been provided that LPL produced by macrophages in the vessel wall exerts proatherogenic effects. The atherogenic effects of LPL have been mainly attributed to its ability to favor lipid accumulation within macrophages present in the atherosclerotic lesion. Recently, it has also been shown that LPL promote the development of atherosclerosis through facilitation of monocyte adhesion to endothelial cells, stimulation of tumor necrosis factor alpha (TNF ) secretion and induction of vascular smooth muscle cell proliferation.

Supplier: Adipogen

APRIL is a cytokine that belongs to the TNF superfamily and binds to TACI and BCMA. It is implicated in the regulation of tumor cell growth, is involved in monocyte/macrophage-mediated immunological processes and functions as an important survival factor for plasmablasts and bone marrow plasma cells. MultimericAPRIL™ is a high activity construct in which two trimeric APRIL ligands are artificially linked via the collagen domain of ACRP30. This construct very effectively stimulates proliferation B cell. A basic amino acid sequence (QKQKKQ) close to the NH2 terminus of APRIL is required for binding to negatively charged sulfated glycosaminoglycan side chains of proteoglycans. Proteoglycans mediate binding of APRIL to tumor cells as well as primary lymphoid cells.

Supplier: Adipogen

APRIL is a cytokine that belongs to the TNF superfamily and binds to TACI and BCMA. It is implicated in the regulation of tumor cell growth, is involved in monocyte/macrophage-mediated immunological processes and functions as an important survival factor for plasmablasts and bone marrow plasma cells. MultimericAPRIL™ is a high activity construct in which two trimeric APRIL ligands are artificially linked via the collagen domain of ACRP30. This construct very effectively stimulates proliferation B cell. A basic amino acid sequence (QKQKKQ) close to the N-terminus of APRIL is required for binding to negatively charged sulfated glycosaminoglycan side chains of proteoglycans. Proteoglycans mediate binding of APRIL to tumor cells as well as primary lymphoid cells.

Supplier: Adipogen

Stem cell factor (SCF), also known as cKit ligand (KL), mast cell growth factor (MGF), and steel factor (SLF), is a widely expressed 28-40 kDa type I transmembrane glycoprotein. It promotes the survival, differentiation, and mobilization of multiple cell types including myeloid, erythroid, megakaryocytic, lymphoid, germ cell, and melanocyte progenitors. SCF is a primary growth and activation factor for mast cells and eosinophils. Noncovalent dimers of transmembrane or soluble SCF interact with the receptor tyrosine kinase SCF R/cKit to trigger receptor dimerization and signaling. SCF assists in the recovery of cardiac function following myocardial infarction by increasing the number of cardiomyocytes and vascular channels.

Supplier: Adipogen

Tight-binding, reversible, highly selective inhibitor of acid proteases (aspartyl peptidases), like pepsin, gastricsin, cathepsin E and D, renin, chymosin, bacterial aspartic proteinases and HIV proteases. Does not inhibit thiol proteases, neutral proteases or serine proteases. Widely used as a research tool in studies of protease mechanisms and biological functions. Solubilized gamma-secretase and retroviral protease inhibitor. Shows antibacterial, antifungal and antiparasitic activity. Suppresses p53-dependent apoptosis in lymphoid cells as well as TNFalpha-induced apoptosis in U937 cells. Inhibits degradation of autophagic cargo inside autophagolysosomes.

Supplier: BioVendor

Complement C1q tumor necrosis factor-related protein 9 (C1q/TNF-related protein 9; CTRP9) is a highly conserved paralog of adiponectin. Of all the CTRP paralogs, CTRP9 shows the highest degree of amino acid identity to adiponectin in its globular C1q domain. CTRP9 protein exists in two isoforms, CTRP9A and CTRP9B. Although human CTRP9A and CTRP9B share 98% amino acid identity, they are encoded by distinct genes and are biochemically distinct. Human CTRP9A but not CTRP9B is expressed by adipose tissue. CTRP9B is expressed at very low levels in tissues. While CTRP9A is robustly secreted as a multimeric protein, CTRP9B requires physical association with CTRP9A or adiponectin for its secretion. CTRP9 is expressed predominantly in adipose tissue and females express higher levels of the transcript than males. Moreover, its expression levels in ob/ob mice changed in an agedependent manner, with significant up-regulation in younger mice. Adenovirus-mediated overexpression of CTRP9 in obese (ob/ob) mice significantly lowered serum glucose levels.

Supplier: Stemcell Technologies

Fractalkine (CX3CL1) is a unique chemokine belonging to the CX3C family, and is characterized by a C-X3-C cysteine motif within the chemokine domain, near the amino terminus of the protein (Bazan et al.). The chemokine domain is connected to an extended mucin-like stalk, followed by a transmembrane region, and a C-terminal intracellular domain (Imai et al.; Jones et al.). The protein signals through interaction with a single receptor, CX3CR1, expressed on monocytes, natural killer cells, T cells, microglia, and smooth muscle cells. Fractalkine is upregulated in endothelial cells by inflammatory signals and is synthesized as a membrane-bound molecule that mediates cell migration and adhesion (White and Greaves). Cleavage at the base of the stalk by metalloproteinases generates a soluble chemokine, which functions as a potent chemoattractant of target cells (Garton et al.; Apostolakis and Spandidos). Fractalkine has been implicated in pathology of inflammatory diseases, such as atherosclerosis and other vascular diseases, and has anti-apoptotic functions (White and Greaves).

Supplier: Anaspec

Matrix Metalloproteinases (MMPs) are a large family of endopeptidases. Collectively, MMPs can degrade all kinds of extracellular matrix proteins, and can also process a number of bioactive molecules. They are known to be involved in the cleavage of cell surface receptors, the release of apoptotic ligands, and chemokine/cytokine inactivation. MMPs are also thought to play a major role in cell behaviors such as cell proliferation, migration (adhesion/dispersion), differentiation, angiogenesis, apoptosis, and host defense.
This substrate is hydrolyzed rapidly by MMP-13, but slowly by MMP-1, 2, 3, 8, 9 and 12, Abs/Em = 494/521 nm.
Sequence:QXL™ 520-PLGLWArK(5-FAM)-NH2
MW:1789.9 Da
% peak area by HPLC:95
Storage condition:-20° C

Supplier: Stemcell Technologies

Fibroblast growth factor 6 (FGF-6) is a heparin-binding member of the FGF family, regulators of cell proliferation, differentiation, and function. FGF-6 binds and signals through the FGF receptors 1c, 2c, and 4 (Ornitz et al.). FGF-6 is a potent mitogen for fibroblasts, vascular endothelial cells, and prostate carcinoma cells (Asada et al.; Pizette et al.; Ropiquet et al.). FGF-6 is primarily expressed in epithelial and mesenchymal cell lineages. During development, FGF-6 is expressed in skeletal muscle, consistent with its role in muscle differentiation and regeneration (Floss et al.). FGF-6 has also been shown to promote chondrogenesis in embryonic somites in conjunction with transforming growth factor beta 2 (TGF-β2; Grass et al.).

Supplier: Stemcell Technologies

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 lyophilized with ≥92% purity, and endotoxin levels are verified to be ≤1.0 EU/μg protein.

Supplier: Anaspec

This peptide is PACAP (1-38) with a Biotin label on its N-terminus. Pituitary adenylate cyclase-activating polypeptide (PACAP), a member of the vasoactive intestinal peptide/secretin/glucagon family, has an amino acid sequence identity of 68% with vasoactive intestinal polypeptide (VIP). PACAP38, derived from a 176-amino acid precursor (preproPACAP), is a 38-amino acid peptide discovered as an ovine hypothalamic neuropeptide. The amino acid sequence of PACAP is identical in all mammals, and in species such as chicken, frog, salmon, only 1–3 amino acids are different. It is abundant in both the central and peripheral nervous systems and exerts a variety of effects. PACAP in pancreatic islets may play a parasympathetic and sensory neurotransmitter role. PACAP stimulates insulin secretion from islets in a glucose-dependent manner at femtomolar concentrations, acting as an insulinotropic factor. PACAP and VIP are two multifunctional neuropeptides modulating innate and adaptive immunity. VIP/PACAP protect T cells from activation-induced cell death through down-regulation of Fas ligand. PACAP immunoreactivity has been shown in nerve fibers innervating the intrapancreatic ganglia as well as the islets of Langerhans in pancreas. PACAP (1-38) is more active than VIP in stimulating adenylate cyclase EC50=7 nM.
Sequence: HSDGIFTDSYSRYRKQMAVKKYLAAVLGKRYKQRVKNKK(Biotin)-NH2
MW: 4888.8 Da
% Peak area by HPLC: 95
Storage condition: -20° C

Supplier: Stemcell Technologies

Tumor necrosis factor-α (TNF-α) is a pro-inflammatory cytokine that activates NF-kB, 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 immuno- suppressive 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 and Hosek). Other effects of TNF-α include vasodilatation and edema formation. This product is animal component-free.

Supplier: Stemcell Technologies

Fibroblast growth factor 16 (FGF-16) is a heparin-binding member of the FGF family. FGFs possess broad mitogenic and cell survival activities and are expressed during embryonic development. FGFs act primarily on cells of mesodermal and neuroectodermal origin to regulate diverse physiological functions including angiogenesis, cell growth, pattern formation, embryonic development, metabolic regulation, cell migration, and tissue repair (Goldfarb; Green et al.). in vitro, FGF-16 has been shown to promote the proliferation of brown adipocytes and in rat embryos it is predominantly expressed in these cells. FGF-16 has also been shown to play a critical role in embryonic heart development and is thought to play a cardioprotective role after birth (Hotta et al.; Lu et al.; Wang et al.).

Supplier: Stemcell Technologies

Use hepassocin to bind to lymphocyte-activation gene 3 (LAG-3) in an MHC class II independent manner, and inhibit antigen-specific T-cell activation (Wang et al.). Hepassocin is known to play a restorative role in the liver, reducing apoptosis and accelerating hepatocyte proliferation in vivo (Li et al.). In addition to these hepatoprotective effects, studies have shown that hepassocin expression is upregulated in gastric cancer tissues (Zhang et al.) and in breast cancer cells (Du et al.), suggesting it has potential to predict cancer disease progression. Hepassocin is a member of the fibrinogen superfamily, whose members share a fibrinogen domain at their C-terminus. It is predominantly expressed in the liver, and weakly in the pancreas (Hara et al.), and is secreted as a homodimer that consists of 312 amino acids. Hepassocin is an acute-phase reactant whose expression in HepG2 cells has been shown to be regulated by IL-6 (Liu and Ukomadu). This protein product contains a His-residue tag at the carboxyl end of the polypeptide chain. For consistency and reproducibility across your applications, hepassocin from STEMCELL comes lyophilized with ≥ 87% purity, and endotoxin levels are verified to be ≤1.0 EU/μg protein.

Supplier: Stemcell Technologies

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, bone formation and resorption (Sims and Quinn; Tanaka and Miyajima).

Supplier: Advanced Biomatrix

Vitronectin is a monomeric glycoprotein used to promote cell attachment, migration, proliferation and differentiation in a broad number of cell lines and types. This product has been purified from human plasma where it is found as a mixture of 75kDa and 65kDa polypeptides.

Vitronectin’s primary use in cell culture is related to cell adhesion. It also binds to heparin and collagen.

Vitronectin is ideal for coating of surfaces. The optimal concentration for cell attachment and culture may differ for various cell types. Vitronectin has been used at a final coating concentration as low as 50 ng/cm2 on plasticware. It is provided in user-friendly packaging for use and storage. Vitronectin is sterile filtered and is supplied as a ready to use solution after thawing and concentration adjustment. This product is shipped separately on dry ice.

Supplier: Stemcell Technologies

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.).

Supplier: Stemcell Technologies

Interleukin 17A (IL-17A) is the founding member of the family of cytokines that includes IL-17B through IL-17F. It is a potent pro-inflammatory cytokine that plays a key role in defense against pathogens. IL-17A and IL-17F signal as homodimers or heterodimers through the same receptor, and activate NF-κB, MAPK, and C/EBP pathways (Gaffen). IL-17A is produced by Th17 cells, CD8+ T cells, γ/δ T cells, natural killer (NK) T cells, B cells, innate lymphoid cells, and mesenchymal stromal cells (MSCs) (Cua and Tato; Gaffen; Mojsilović et al.). IL-17A mediates protection against extracellular pathogens, and together with IL-22 stimulates production of antimicrobial peptides. It induces granulopoiesis factors and neutrophil-specific chemokines. Together with tumor necrosis factor alpha (TNF-α), IL-17A induces a sustained neutrophil recruitment during inflammation (Cua and Tato). IL-17A receptor is expressed at particularly high levels on stromal cells, including MSCs. IL-17A increases the frequency and the average size of fibroblast colony-forming units (CFU-F), as well as the proliferation of marrow-derived MSCs. It enhances osteogenic differentiation, and inhibits adipocyte differentiation and chondrogenesis (Mojsilović et al.).

Supplier: Advanced Biomatrix

Advanced BioMatrix offers PhotoCol®, a purified methacrylated Type I bovine collagen kit. PhotoCol® provides native-like 3D collagen gels with the unique attributes to be prepared at various concentrations and crosslinked to provide various gel stiffness.

The PhotoCol® kit consists of purified methacrylated Type I bovine collagen as the core component with other support reagents in the kit.

The methacrylated Type I collagen is produced from telo-peptide intact bovine collagen where the collagen has been modified by reacting the free amines, primarily the e-amines groups of the lysine residues as well as the a-amines groups on the N-termini. Approximately 40% of the total lysine residues of the collagen molecule have been methacrylated. The collagen is extracted from bovine hide and contains a high monomer content. The collagen starting material was isolated from a closed herd and purified using controlled manufacturing processes. A bottle of 20 mM acetic acid solution is provided to solubilize the lyophilized methacrylated collagen at concentrations ranging from 3 to 8 mg/ml.The neutralization solution consists of an alkaline 10X phosphate buffered saline (PBS) solution which provides physiological salts and pH in the final mixture.The photoinitiator consists of Irgacure 2959 to be formulated in methanol (methanol not included) which allows UV crosslinking of the collagen at 365 nm.

Supplier: Stemcell Technologies

Granulocyte colony-stimulating factor (G-CSF) is a member of the CSF family of glycoproteins that regulate hematopoietic cell proliferation, differentiation, and function. It is a key cytokine involved in the production of neutrophils and the stimulation of granulocyte colony formation from hematopoietic progenitor cells (Metcalf andamp; Nicola). G-CSF causes a range of effects including a transient reduction of SDF-1 expression (Petit et al.), the activation of metalloproteases that cleave VCAM-1 (Levesque et al.), and the release of norepinephrine from the sympathetic nervous system (Katayama et al.), leading to the release or mobilization of hematopoietic stem cells from the bone marrow into the periphery. The G-CSF receptor is expressed on a variety of hematopoietic cells, including myeloid-committed progenitor cells, neutrophils, granulocytes, and monocytes. In addition to hematopoietic cells, G-CSF is also expressed in cardiomyocytes, neuronal cells, mesothelial cells, and endothelial cells. Binding of G-CSF to its receptor leads to activation of the JAK/STAT, MAPK, PI3K, and AKT signal transduction pathways.

Supplier: Adipogen

Epidermal growth factor (EGF) is a growth factor and the founding member of the EGF family. All EGF family members are synthesized as type I transmembrane precursor proteins that may contain several EGF domains in the extracellular region. The mature proteins are released from the cell surface by regulated proteolysis. EGF is present in various body fluids, including blood, milk, urine, saliva, seminal fluid, pancreatic juice, cerebrospinal fluid, and amniotic fluid. Four ErbB (HER) family receptor tyrosine kinases including EGFR/ErbB1, ErbB2, ErbB3 and ErbB4, mediate responses to EGF family members. These receptors undergo a complex pattern of ligand induced homo or heterodimerization to transduce EGF family signals. EGF binds to the receptor EGFR stimulating the intrinsic protein-tyrosine kinase activity of the receptor. The tyrosine kinase activity initiates a signal transduction cascade that results in a variety of biochemical changes within the cell, including a rise in intracellular calcium levels, increased glycolysis and protein synthesis, and increases in the expression of certain genes including the gene for EGFR, which lead to DNA synthesis, cell growth, proliferation and differentiation. Other biological activities ascribed to EGF include epithelial development, angiogenesis, inhibition of gastric acid secretion, fibroblast proliferation, and colony formation of epidermal cells in culture. Defects in EGF are the cause of hypomagnesemia type 4 (HOMG4), also known as renal hypomagnesemia normocalciuric. HOMG4 is a disorder characterized by massive renal hypomagnesemia and normal levels of serum calcium and calcium excretion. Clinical features include seizures, mild-to mederate psychomotor retardation, and brisk tendon reflexes.

Supplier: Adipogen

NF-kappaB is a pleiotropic transcription factor present in almost all cell types and is the endpoint of a series of signal transduction events that are initiated by a vast array of stimuli related to many biological processes such as inflammation, immunity, differentiation, cell growth, tumorigenesis and apoptosis. NF-kappaB is a homo- or heterodimeric complex formed by the Rel-like domain-containing proteins RELA/p65, RELB, NFKB1/p105, NFKB1/p50, REL and NFKB2/p52. The heterodimeric p65-p50 complex is the most abundant complex. The dimers bind at kappaB sites in the DNA of their target genes and the individual dimers have distinct preferences for different kappaB sites that they can bind with distinguishable affinity and specificity. Different dimer combinations act as transcriptional activators or repressors, respectively. NF-kappaB complexes are held in the cytoplasm in an inactive state complexed with members of the NF-kappaB inhibitor (I-kappaB) family. In a conventional activation pathway, I-kappaB is phosphorylated by I-kappaB kinases (IKKs) in response to different activators, subsequently degraded thus liberating the active NF-kappaB complex which translocates to the nucleus. NF-kappaB heterodimeric p65-p50 and RelB-p50 complexes are transcriptional activators. The NF-kappaB p50-p50 homodimer is a transcriptional repressor, but can act as a transcriptional activator when associated with BCL3.

Supplier: BioVendor

A DNA sequence encoding the mature variant of ovVEGF-E isolate D1701 (Dehio et al., 1999; GenBank accession No. AF106020) was expressed in E. coli as a 132 amino acid residue fusion protein with an N-terminal His-tag sequence and a thrombin cleavage site. Recombinant VEGF-E homodimer was dimerized in vitro and has a predicted mass of approximately 35 kDa. Based on sequence similarity to VEGF-A, a gene encoding a VEGF homologue has recently been discovered in the genome of Orf virus (OV) (Lyttle et al., 1994). Different isolates of Orf virus show significant amino acid sequence similarity to VEGF-A and described as a viral virulence factor that appears to be derived from captured host genes. All eight cysteine residues of the central cysteine knot motif characteristic of members of the VEGF family are conserved among other residues in the VEGF-E proteins (Dehio et al., 1999; Wise et al., 1999). Alignment of all mammalian VEGF sequences indicated that VEGF-E is distinct from the previously described VEGFs but most closely related to VEGF-A. Like VEGF-A, VEGF-E was found to bind with high affinity to VEGF receptor-2 (KDR) resulting in receptor autophosphorylation, whilst in contrast to VEGF-A, VEGF-E can not bind to VEGF receptor-1 (Flt-1). Furthermore VEGF-E can also not bind to VEGF receptor-3 (FLT-4). Therefore VEGF-E is a potent angiogenic factor selectively binding to VEGF receptor –2/KDR.

Supplier: Stemcell Technologies

RANTES (regulated upon activation, normal T cell expressed and secreted), also known as CCL5, is a member of the CC family of chemokines and is able to recruit leukocytes to sites of inflammation (Schall et al.). RANTES is secreted by T lymphocytes, macrophages, platelets, synovial fibroblasts, tubular epithelium, and certain types of tumor cells (Aldinucci and Colombatti; Soria and Ben-Baruch). This chemokine exerts its effect by interacting with the chemokine receptors CCR1, CCR3, CCR4, and CCR5. RANTES plays an active role in recruiting a variety of leukocytes into inflammatory sites, including T cells, macrophages, eosinophils, and basophils. In collaboration with certain cytokines that are released by T cells such as IL-2 and IFN-γ, RANTES also induces the activation and proliferation of NK cells to generate CC chemokine-activated killer cells, which are highly cytolytic (Lv et al.; Maghazachi et al.). It has been shown that RANTES produced by CD8+ T cells inhibits HIV infection of primary human peripheral blood mononuclear cells (Appay and Rowland-Jones; Cocchi et al.).

Supplier: Adipogen

Interleukin-23 (IL-23) is a heterodimeric cytokine composed of two disulfide-linked subunits, a p19 subunit that is unique to IL-23, and a p40 subunit that is shared with IL-12 (1-5). Although p19 is expressed by activated macrophages, dendritic cells, T cells, and endothelial cells, only activated macrophages and dendritic cells express p40 concurrently to produce IL-23. The functional IL-23 receptor complex consists of two receptor subunits, the IL-12 receptor beta 1 subunit (IL-12 Rbeta1) and the IL-23-specific receptor subunit (IL-23 R). IL-23 has biological activities that are similar to, but distinct from IL-12. Both IL-12 and IL-23 induce proliferation and IFN-gamma production by human T cells. While IL-12 acts on both naie and memory human T cells, the effects of IL-23 is restricted to memory T cells. In mouse, IL-23 but not IL-12, has also been shown to induce memory T cells to secret IL-17, a potent proinflammatory cytokine. IL-12 and IL-23 can induce IL-12 production from mouse splenic DC of both the CD8-and CD8+ subtypes, however only IL-23 can act directly on CD8+ DC to mediate immunogenic presentation of poorly immunogenic tumor/self peptide.

Supplier: Adipogen

CD152 and CD28, together with their ligands B7-1 and B7-2, constitute one of the dominant costimulatory pathways that regulate T and B cell responses. CD152 and CD28 are structurally homologous molecules that are members of the immunoglobulin (Ig) gene superfamily. Both CD152 and CD28 are composed of a single Ig V-like extracellular domain, a transmembrane domain and an intracellular domain. CD152 and CD28 are both expressed on the cell surface as disulfide-linked homodimers or as monomers. CD152 was originally identified as a gene that was specifically expressed by cytotoxic T lymphocytes. However, CD152 transcripts have since been found in both Th1 and Th2, and CD4+ and CD8+ T cell clones. Whereas, CD28 expression is constitutive on the surfaces of 95% of CD4+ T cells and 50% of CD8+ T cells and is down regulated upon T cell activation, CD152 expression is upregulated rapidly following T cell activation and peaks approximately 24 hours following activation. Although both CD152 and CD28 can bind to the same ligands, CD152 binds to B71 and B72 with 20-100-fold higher affinity than CD28.

Supplier: Stemcell Technologies

The platelet-derived growth factor (PDGF) family has five heparin-binding members that assemble into four homodimers (PDGF-AA, PDGF-BB, PDGF-CC, and PDGF-DD) and one heterodimer (PDGF-AB; Fretto et al.; Li and Eriksson). PDGF signals through the receptor tyrosine kinases PDGFRα and PDGFRβ. It has been shown that PDGF-induced migration involves signaling pathways involving MEK/ERK, EGFR, Src, and PI3K/AKT (Kim et al.). PDGF is a potent mitogen for cells of mesenchymal origin, such as fibroblasts, glial cells, and vascular smooth muscle cells. PDGF has been implicated in pathogenesis of atherosclerosis, glomerulonephritis, cancer, and in the contraction of vascular smooth muscle cells of rat aortic tissues (Fretto et al.; Sachinidis et al.). PDGF-BB is secreted by osteoblasts to induce mesenchymal stem cell migration and angiogenesis. It has also been shown that PDGF-BB is secreted by preosteoclasts during bone modeling and remodeling to induce angiogenesis and thus proper osteogenesis (Xie et al.).

Supplier: Stemcell Technologies

Interleukin 10 (IL-10) is the founding member of the IL-10 family of class II cytokines. All of the IL-10 cytokine family members have a four-helix bundle consisting of α-helical folds. Upon binding to its receptor, IL-10 activates signaling through JAK1 and STAT3. It is produced by dendritic cells, macrophages, and CD4+ T regulatory cells, as well as mast cells, NK cells, neutrophils, and regulatory B cells, under specific stimulating conditions (Saraiva and O'Garra). IL-10 can inhibit the activation of certain immune cells while it promotes the function of B cells, and facilitate healing process. Specifically, this cytokine is important for the function of T regulatory cells as it is a potent suppressor of effector T cell proliferation and cytokine production. Also, IL-10 produced by a subset of macrophages inhibits activation and production of pro-inflammatory cytokines by neighboring macrophages, thus allowing a level of self-regulation. IL-10 enhances B cell proliferation, immunoglobulin secretion, and class II MHC expression (Ouyang et al.).

Supplier: Adipogen

Interleukin-21 receptor (IL-21R) is a type I transmembrane glycoprotein within the class I cytokine receptor family, type 4 subfamily. Complex formation between IL-21R and the common gamma chain (gammac) is required for signaling. IL-21R is expressed mainly on B cells (highest on mature, activated, follicular and germinal center B cells), NK cells and activated T cells, but is also found on dendritic cells, alternatively activated macrophages, intestinal lamina propria fibroblasts and epithelial cells and keratinocytes. B cell IL-21R engagement induces Blimp1 (which mediates plasma cell differentiation) and is important for memory responses. IL-21R engagement on mouse NK cells enhances their cytotoxic activity and IFN-gamma production. IL-21R engagement on CD8+ T cells aids control of viral infection and tumor growth; IL-21R is also necessary for sufficient numbers of regulatory T cells to combat chronic inflammation. IL-21R expression is often upregulated in allergic skin inflammation, systemic lupus erythematosus and diffuse large B cell lymphoma (DLBCL).