You searched for: Proteins and Peptides

Supplier: Stemcell Technologies

Interferon-gamma (IFN-γ), also known as type II interferon, is produced by T and NK cells, and in smaller amounts by dendritic cells and macrophages. IFN-γ is controlled by cytokines such as IL-12 and IL-18 secreted in response to infection (Schroder et al.). IFN-γ binds to a receptor complex and initiates signal transduction via the JAK/STAT pathway; this culminates in the transcription and activation of many genes that control a diverse array of immunological functions (De Weerd and Nguyen; Krause et al.). IFN-γ stimulates the antimicrobial and anti-tumor activity of macrophages, NK cells, and neutrophils (Billiau and Matthys) by promoting the activation of microbial effector functions such as production of reactive oxygen species, NO intermediates, complement, etc. (Schroder et al.). IFN-γ enhances MHC class I and II expression in dendritic cells and mononuclear phagocytes, as well as the production of IL-12 by dendritic cells. In B cells, IFN-γ stimulates survival and growth in both mouse and human cells, and redirects B cells from proliferation towards differentiation. IFN-γ favors the development of Th1 vs Th2 cells and stimulates monocyte differentiation and function (Schroder et al.).

Supplier: Stemcell Technologies

Granulocyte-macrophage colony-stimulating factor (GM-CSF) promotes the proliferation and differentiation of hematopoietic progenitor cells and the generation of neutrophils, eosinophils, and macrophages. In synergy with other cytokines such as stem cell factor, IL-3, erythropoietin, and thrombopoietin, it also stimulates erythroid and megakaryocyte progenitor cells (Barreda et al.). GM-CSF was first purified from the culture of mouse lung tissue after lipopolysaccharide treatment. GM-CSF is produced by multiple cell types, including stromal cells, Paneth cells, macrophages, dendritic cells (DCs), endothelial cells, smooth muscle cells, fibroblasts, chondrocytes, and Th1 and Th17 cells (Francisco-Cruz et al.). The receptor for GM-CSF (GM-CSFR) is composed of two subunits: the cytokine-specific α subunit (GMRα; CD116) and the common subunit βc (CD131) shared with IL-3 and IL-5 receptors (Broughton et al.). GM-CSFR is expressed on hematopoietic cells, including progenitor cells and immune cells, as well as non-hematopoietic cells. GM-CSF is able to stimulate the development of DCs that ingest, process, and present antigens to the immune system (Francisco-Cruz et al.).

Supplier: Adipogen

CD28 and CTLA-4 together with their ligands, CD80 (B7-1) and CD86 (B7-2), constitute one of the dominant costimulatory pathways that regulate T and B cell responses. CD28 and CTLA-4 are structurally homologous molecules that are members of the immunoglobulin (Ig) gene superfamily. Both CD28 and CTLA-4 are composed of a single Ig V-like extracellular domain, a transmembrane domain and an intracellular domain. CD28 and CTLA-4 are both expressed on the cell surface as disulfide-linked homodimers or as monomers. The genes encoding these two molecules are closely linked on human chromosome 2 and mouse chromosome 1. Mouse CD28 is expressed constitutively on virtually 100% of mouse T cells and on developing thymocytes. Cell surface expression of mouse CD28 is downregulated upon ligation of CD28 in the presence of PMA or PHA. In contrast, CTLA-4 is not expressed constitutively but is upregulated rapidly following T cell activation and CD28 ligation. Cell surface expression of mouse CTLA-4 peaks approx.y 48 hours after activation. Although both CTLA-4 and CD28 can bind to the same ligands, CTLA-4 binds to B7-1 and B7-2 with a 20-100 fold higher affinity than CD28. CD28/B7 interaction has been shown to prevent apoptosis of activated T cells via the upregulation of bcl-XL. CD28 ligation has also been shown to regulate Th1/Th2 differentiation.

Supplier: Adipogen

CD28 and CTLA-4 together with their ligands, CD80 (B7-1) and CD86 (B7-2), constitute one of the dominant costimulatory pathways that regulate T and B cell responses. CD28 and CTLA-4 are structurally homologous molecules that are members of the immunoglobulin (Ig) gene superfamily. Both CD28 and CTLA-4 are composed of a single Ig V-like extracellular domain, a transmembrane domain and an intracellular domain. CD28 and CTLA-4 are both expressed on the cell surface as disulfide-linked homodimers or as monomers. The genes encoding these two molecules are closely linked on human chromosome 2 and mouse chromosome 1. Mouse CD28 is expressed constitutively on virtually 100% of mouse T cells and on developing thymocytes. Cell surface expression of mouse CD28 is downregulated upon ligation of CD28 in the presence of PMA or PHA. In contrast, CTLA-4 is not expressed constitutively but is upregulated rapidly following T cell activation and CD28 ligation. Cell surface expression of mouse CTLA-4 peaks approx.y 48 hours after activation. Although both CTLA-4 and CD28 can bind to the same ligands, CTLA-4 binds to B7-1 and B7-2 with a 20-100 fold higher affinity than CD28. CD28/B7 interaction has been shown to prevent apoptosis of activated T cells via the upregulation of bcl-XL. CD28 ligation has also been shown to regulate Th1/Th2 differentiation.

Supplier: Advanced Biomatrix

Type IV Collagen is the primary collagen found in the extracellular basement membranes separating a variety of epithelial and endothelial cells. It is a major component of the dermal-epidermal junction where it is mostly found in the lamina densa. It is a heterotrimeric molecule containing two Alpha 1-like and one Alpha 2-like chains.

This Type IV Collagen is isolated from human placenta and is purified using a multi-step process. The product is supplied as a sterile, lyophilized powder containing 5 mg of Type IV collagen per vial. A Certificate of Analysis is available with the purchase of each product.

Type IV Collagen is typically used as a thin coating on tissue culture surfaces. Specific instructions are found in the Directions for Use. This product is generally used in vitro as a substrate scaffold to enhance cell attachment, adherence and proliferation. Type IV collagen may be used to culture epithelial, endothelial, muscle, nerve and many other cell types. Additionally, this product is suitable for use as a substrate for collagenase assays and positive controls.

Supplier: Advanced Biomatrix

Type IV Collagen is the primary collagen found in the extracellular basement membranes separating a variety of epithelial and endothelial cells. It is a major component of the dermal-epidermal junction where it is mostly found in the lamina densa. It is a heterotrimeric molecule containing two Alpha 1-like and one Alpha 2-like chains.

This Type IV Collagen is isolated from human placenta and is purified using a multi-step process. The product is supplied as a non-sterile powder containing 5 mg of Type IV collagen per vial. A Certificate of Analysis is available with the purchase of each product.

Type IV Collagen is typically used as a thin coating on tissue culture surfaces. Specific instructions are found in the Directions for Use. This product is generally used in vitro as a substrate scaffold to enhance cell attachment, adherence and proliferation. Type IV collagen may be used to culture epithelial, endothelial, muscle, nerve and many other cell types. Additionally, this product is suitable for use as a substrate for collagenase assays and positive controls.

Supplier: Stemcell Technologies

Flt3/Flk-2 (Fms-like tyrosine kinase 3/fetal liver kinase-2) Ligand is a hematopoietic cytokine that plays an important role as a co-stimulatory factor in the proliferation, differentiation, and survival of hematopoietic stem and progenitor cells and the development of the immune system (Hannum et al.). Flt3/Flk-2 Ligand, together with stem cell factor and thrombopoietin, is commonly used to promote expansion of primitive CD34+ hematopoietic cells in culture. In combination with myeloid cytokines such as GM-CSF, G-CSF, or M-CSF, Flt3/Flk-2 Ligand enhances the growth and numbers of clonogenic myeloid progenitor cells. In synergy with the interleukins IL-3, IL-4, IL-7, IL-11, IL-12, IL-15, and GM-CSF and TNF-α, Flt3/Flk-2 Ligand regulates the development of various lymphoid progenitor cells, including dendritic cell, B cell, T cell, and NK cell progenitors. In contrast, Flt3/Flk-2 Ligand has no significant effect on erythropoiesis or megakaryopoiesis (Drexler and Quentmeier; Wodnar-Filipowicz). Flt3/Flk-2 Ligand exists as membrane-bound and soluble isoforms. Both isoforms are biologically active and signal through the class III tyrosine kinase receptor (Flt3/Flk-2, CD135; Rosnet et al.). Flt3/Flk-2 Ligand is produced by a variety of cell types, including uncommitted and committed hematopoietic cells and stromal fibroblasts, whereas expression of the Flt3/Flk-2 receptor is restricted to CD34+ hematopoietic stem and progenitor cells. Flt3/Flk-2 receptor is also expressed on leukemic cells and outside the hematopoietic system in the brain, placenta, and testis (Drexler and Quentmeier; Hannum et al.). This product is animal component-free.

Supplier: Adipogen

Interleukin-15 (IL-15) has a broad spectrum of biological activities. It is crucial for the development, proliferation, survival and differentiation of multiple cells from both innate and adaptive immune systems. IL-15 up-regulation has a central role in the development of several autoimmune or chronic inflammatory disorders. Targeting IL-15 or its receptor may have a valuable impact on the treatment of immune-mediated diseases. IL-15 participates in the development of important immune antitumor mechanisms. It activates CD8(+) T cells, natural killer (NK) cells, NK T cells, and can promote the formation of antitumor antibodies. IL-15 can also protect T effector cells from the action of T regulatory cells and reverse tolerance to tumor-associated antigens. In pre-clinical studies IL-15 has been found to demonstrate potentiated antitumor effects following pre-association with IL-15Ralpha, or when used in combination with chemotherapy, adoptive therapy, monoclonal antibodies, and tumor vaccines. Application: Useful for immunofluorescent staining and flow cytometric analysis to identify and enumerate IL-15Ralpha expressing cells within mixed cell populations.

Supplier: BioVendor

Visceral adipose tissue – derived serpin A12 (vaspin), also named OL-64, an adipocytokine, is structurally a member of the serine protease family. Serpins are the most diverse family of protease inhibitors. Their typical structural feature is the core domain composed from 3 beta-sheets and 9 alpha-helixes. The inhibitory activity of vaspin has not been described up to now, but its reactive site loop is typical for this proteinase family. Human Vaspin protein is composed of 395 amino acids and has a molecular weight of approximately 45.2 kDa and predicted pI 9.26. The cDNA was first isolated from white adipose tissue of Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Vaspin mRNA expression is specific for visceral adipose tissues and it is also found circulating in the serum. The level of serum vaspin increased with age up to the peak of obesity, body weight and insulin resistance in OLETF rats and decreases with worsening of diabetes. Vaspin expression is missing in the diabetes-resistant lean rats, LETO, in comparison to OLEFT rats, animal model of metabolic syndrome. Expression was also absent in the subdermal, brown fatty tissue and other non-adipose tissues in OLEFT rats. These findings lead to the conclusion that the target tissue for insulin sensitising effect of vaspin is white adipose tissue. In humans, elevated serum concentration of vaspin is associated with obesity and impaired insulin sensitivity.

Supplier: Stemcell Technologies

Interleukin 34 (IL-34) is well known for its ability to induce the formation of colony-forming unit macrophages in human bone marrow cell cultures (Foucher et al.; Wei et al.). This dimeric glycoprotein is a member of the short-chain helical hematopoietic cytokine family (Baghdadi et al.; Foucher et al.), and exists in two isoforms that differ by a single glutamine (Chen et al.; Foucher et al; Wei et al.). IL-34 interacts with M-CSF to trigger tyrosine phosphorylation of the receptor and ERK1/2 pathways. (Wang et al.; Wei et al.). It is expressed in many tissues (heart, brain, lung, liver, kidney, thymus, testes, ovary, small intestine, prostate, and colon), with the highest expression in the spleen. In combination with RANKL (MSPP-78214), IL-34 induces osteoclast differentiation (Chen et al.; Foucher et al.). IL-34 expression is decreased in Alzheimer’s disease and atopic dermatitis, while high levels of IL-34 are found in many types of cancer correlated with poor prognosis, chronic heart failure or coronary artery disease, inflammatory bowel disease, influenza A infection, during acute liver transplant rejection or in non-alcoholic fatty liver disease, and with rheumatoid arthritis (Baghdadi et al.). It is therefore a possible pharmacological target for treating bone or inflammatory diseases (Chen et al.). This protein contains a His-residue tag at the carboxyl end of the polypeptide chain, and the protein was purified as a homodimer consisting of 39 kDa monomers (Lin et al.).

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.

Supplier: Stemcell Technologies

Flt3/Flk-2 (Fms-like tyrosine kinase 3/fetal liver kinase-2) ligand is a hematopoietic cytokine that plays an important role as a co-stimulatory factor in the proliferation, differentiation, and survival of hematopoietic stem and progenitor cells and the development of the immune system (Lyman et al.; Rosnet et al.). Flt3/Flk-2 ligand, together with stem cell factor and thrombopoietin, is commonly used to promote expansion of primitive hematopoietic cells in culture. In combination with myeloid cytokines such as GM-CSF, G-CSF, or M-CSF, Flt3/Flk-2 ligand enhances the growth and numbers of clonogenic myeloid progenitor cells. In synergy with IL-3, IL-4, IL-7, IL-11, IL-12, IL-15, GM-CSF, and TNF-α, Flt3/Flk-2 ligand regulates the development of various lymphoid progenitor cells, including dendritic cell, B cell, T cell, and NK cell progenitors. In contrast, Flt3/Flk-2 ligand has no significant effect on erythropoiesis or megakaryopoiesis (Drexler and Quentmeier; Wodnar-Filipowicz). Flt3/Flk-2 ligand exists as membrane-bound and soluble isoforms. Both isoforms are biologically active and signal through the class III tyrosine kinase receptor (Flt3/Flk-2, CD135; Rosnet et al.). Flt3/Flk-2 ligand is produced by a variety of cell types, including uncommitted and committed hematopoietic cells and stromal fibroblasts, whereas expression of the Flt3/Flk-2 receptor is restricted to CD34+ hematopoietic stem and progenitor cells. Flt3/Flk-2 receptor is also expressed outside the hematopoietic system in the brain, placenta, and testis (Drexler and Quentmeier; Hannum et al.).

Supplier: AAT Bioquest

Z-VAD-CHO, also generically called as 'Caspase Inhibitor II', is a cell-permeable, reversible pan-caspase inhibitor, blocks all features of apoptosis in THP.1 and Jurkat T-cells.