Votre recherche pour: Biotium

Fournisseur: Biotium

Description: This antibody recognizes an antigen associated with the nuclear membrane expressed in human cells. It can be used to stain the nuclear membrane in cell or tissue preparations and can be used as a marker of the nuclear membrane in subcellular fractions. It produces a ring pattern around the nucleus of cells of normal and malignant cells and may be used to stain the nuclear membrane of cells in fixed or frozen tissue sections. ,The nuclear envelope (also known as the perinuclear envelope, nuclear membrane, nucleolemma or karyotheca) is the double membrane of the nucleus that encloses genetic material in eukaryotic cells. It separates the contents of the nucleus (DNA in particular) from the cytosol (cytoplasm). Numerous nuclear pores are present on the nuclear envelope to facilitate and regulate the exchange of materials (for example, proteins and RNA) between the nucleus and the cytoplasm. The space between the two membranes that make up the nuclear envelope is called the perinuclear space (also called the perinuclear cisterna), and is usually about 20 - 40 nm wide. Each of the two membranes is composed of a lipid bilayer. The outer membrane is continuous with the rough endoplasmic reticulum. The inner membrane is erected upon the nuclear lamina, a network of intermediate filaments made of lamin, that plays a role in mitosis and meiosis. The type of lamins present are A, B1, B2, and C. The nuclear envelope may also play a role in the disposition of chromatin inside the nucleus. The lamina acts as a site of attachment for chromosomes. It also acts like a shield for the nucleus. During prophase in mitosis, the chromatids begin condensing to form chromosomes, and the nuclear envelope begins to disintegrate. During metaphase, the nuclear envelope is completely disintegrated, and the chromosomes can be pulled apart as chromatids by the spindle fibers.

Fournisseur: Biotium

Description: This antibody recognizes a protein of 55-62 kDa, identified as cyclin B1. In mammals, cyclin B associates with inactive p34cdc2, which facilitates phosphorylation of p34cdc2 at aa 14Thr and 15Tyr. This maintains the inactive state until the end of G2-phase. The inactive cyclin B-p34cdc2 complex continues to accumulate in the cytoplasm until the completion of DNA synthesis, when Cdc25, a specific protein phosphatase, dephosphorylates aa 14Thr and 15Tyr of p34cdc2 rendering the complex active at the G2/M boundary. This mitotic kinase complex remains active until the metaphase/anaphase transition when cyclin B is degraded. This degradation process is ubiquitin-dependent and is necessary for the cell to exit mitosis. So, cyclin B-p34cdc2 plays a critical role in G2 to M transition.

Fournisseur: Biotium

Description: Recognizes a protein of 36 kDa, identified as cyclin D1. Cyclin D1, one of the key cell cycle regulators, is a putative proto-oncogene overexpressed in a wide variety of human neoplasms. This antibody neutralizes the activity of cyclin D1 in vivo. About 60% of mantle cell lymphomas (MCL) contain a t(11; 14)(q13; q32) translocation resulting in over-expression of cyclin D1. This antibody is useful in identifying mantle cell lymphomas (cyclin D1 positive) from CLL/SLL and follicular lymphomas (cyclin D1 negative). Occasionally, hairy cell leukemia and plasma cell myeloma weakly express Cyclin D1.

Fournisseur: Biotium

Description: This MAb reacts with a protein of 22 kDa, identified as beta subunit of HCG. It does not cross react with the alpha subunit. HCG is a glycoprotein, which is secreted in large quantities by normal trophoblasts. It is present only in trace amounts in non-pregnant urine and sera but rises sharply during pregnancy. HCG is composed of two non-identical, non-covalently linked polypeptide chains designated as the alpha and beta subunits. The alpha subunit is identical to that of thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), and luteinizing hormone (LH). hCG MAb detects cells and tumors of trophoblastic origin such as choriocarcinoma. Large cell carcinoma and adenocarcinoma of the lung demonstrate anti-hCG positivity in 90% and 60% of cases respectively. 20% of lung squamous cell carcinomas are positive. hCG expression by non-trophoblastic tumors may indicate aggressive behavior.

Fournisseur: Biotium

Description: This MAb is specific to heavy chain of IgA and shows minimal cross-reaction with heavy chains of other immunoglobulins. It is reactive with both IgA1 and IgA2 subclasses of Alpha heavy chain. It reacts with the third constant domain (CH3) of the alpha chain of IgA molecules. Immunoglobulins are four-chain, Y-shaped, monomeric structures comprised of two identical heavy chains and two identical light chains held together through inter-chain disulfide bonds. The chains form two domains, the Fab (antigen binding) fragment and the Fc (constant) fragment. Immunoglobulin A (IgA) is the main protein of the mucosal immune system. It is generated by B-cells in gut-associated lymphoid tissues. Daily production of IgA exceeds that of any of the other immunoglobulins.IgA exists mainly in dimers but can also exist as polymers or as monomers. Dimers and polymers contain a joining (J) chain that can be bound by the polymeric immunoglobulin receptor (pIgR) for transportation of the molecule to mucosal surfaces. The most common feature of plasmacytomas, and certain non-Hodgkin's lymphomas is the restricted expression of a single heavy chain class. Demonstration of clonality in lymphoid infiltrates indicates that the infiltrate is clonal and therefore malignant.

Fournisseur: Biotium

Description: Recognizes a polypeptide which is identified as insulin, a 51-amino acid polypeptide composed of A and B chains connected through the C-peptide. Proinsulin, which has very little biological activity, is cleaved by proteases within its cell of origin into the insulin molecule and the C-terminal basic residue. Insulin enhances membrane transport of glucose, amino acids, and certain ions. It also promotes glycogen storage, formation of triglycerides, and synthesis of proteins and nucleic acids. Deficiency of insulin results in diabetes mellitus. The main storage site for insulin is the pancreatic islets. Antibodies to insulin are important as beta-cell and insulinoma marker.

Référence Produit: (BTIUBNUM0941-50)

Fournisseur: Biotium

Description: Tumor Necrosis Factor Alpha (TNF alpha) is a protein secreted by lipopolysaccharide-stimulated macrophages, and causes tumor necrosis when injected into tumor bearing mice. TNF alpha is believed to mediate pathogenic shock and tissue injury associated with endotoxemia. TNF alpha exists as a multimer of two, three, or five non-covalently linked units, but shows a single 17 kDa band following SDS PAGE under non-reducing conditions. TNF alpha is closely related to the 25 kDa protein Tumor Necrosis Factor beta (lymphotoxin), sharing the same receptors and cellular actions. TNF alpha causes cytolysis of certain transformed cells, being synergistic with interferon gamma in its cytotoxicity. Although it has little effect on many cultured normal human cells, TNF alpha appears to be directly toxic to vascular endothelial cells. Other actions of TNF alpha include stimulating growth of human fibroblasts and other cell lines, activating polymorphonuclear neutrophils and osteoclasts, and induction of interleukin 1, prostaglandin E2 and collagenase production.

UOM: 1 * 50 µl

*Promo

Fournisseur: Biotium

Description: This MAb reacts with a protein of ~13 kDa, identified as alpha subunit of HCG. HCG is a glycoprotein, which is secreted in large quantities by normal trophoblasts. It is present only in trace amounts in non-pregnant urine and sera but rises sharply during pregnancy. HCG is composed of two non-identical, non-covalently linked polypeptide chains designated as the alpha and beta subunits. The alpha subunit is identical to that of thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), and luteinizing hormone (LH).

Fournisseur: Biotium

Description: This Ab reacts with the rod domain of human cytokeratin 19 (CK19), a polypeptide of 40 kDa. CK19 is expressed in sweat gland, mammary gland ductal and secretory cells, bile ducts, gastrointestinal tract, bladder urothelium, oral epithelia, esophagus, and ectocervical epithelium. Anti-CK19 reacts with a wide variety of epithelial malignancies including adenocarcinomas of the colon, stomach, pancreas, biliary tract, liver, and breast. Perhaps the most useful application is the identification of thyroid carcinoma of the papillary type, although 50%-60% of follicular carcinomas are also labeled. Anti-CK19 is a useful marker for detection of tumor cells in lymph nodes, peripheral blood, bone marrow and breast cancer.

Fournisseur: Biotium

Description: Recognizes a protein of 55 kDa, which is identified as fascin-1. Its actin binding ability is regulated by phosphorylation. Antibody to fascin-1 is a very sensitive marker for Reed-Sternberg cells and variants in nodular sclerosis, mixed cellularity, and lymphocyte depletion Hodgkin's disease. It is uniformly negative in lymphoid cells, plasma cells, and myeloid cells. Fascin-1 is also expressed in dendritic cells. This marker may be helpful to distinguish between Hodgkin lymphoma and non-Hodgkin lymphoma in difficult cases. Also, the lack of expression of fascin-1 in the neoplastic follicles in follicular lymphoma may be helpful in distinguishing these lymphomas from reactive follicular hyperplasia in which the number of follicular dendritic cells is normal or increased. Antibody to fascin-1 has been suggested as a prognostic marker in neuroendocrine neoplasms of the lung as well as in ovarian cancer. Fascin-1 expression may be induced by Epstein-Barr virus (EBV) infection of B cells with the possibility that viral induction of fascin in lymphoid or other cell types must also be considered in EBV-positive cases.

Fournisseur: Biotium

Description: EGP40 is a 40-43 kDa transmembrane epithelial glycoprotein, also identified as epithelial specific antigen (ESA), or epithelial cellular adhesion molecule (Ep-CAM). It is expressed on baso-lateral cell surface in most simple epithelia and a vast majority of carcinomas. This antibody has been used to distinguish adenocarcinoma from pleural mesothelioma and hepatocellular carcinoma. This antibody is also useful in distinguishing serous carcinomas of the ovary from mesothelioma.

Fournisseur: Biotium

Description: Recognizes a protein of 33-37 kDa, identified as CD20 (Workshop V; Code CD20.12). B9E9 recognizes extracellular domain of CD20. The epitope is similar to or identical to that recognized by other CD20 antibodies including Leu-16 and B1. This MAb can be used for immunophenotyping of leukemia and malignant cells, B lymphocyte detection in peripheral blood, B cell localization in tissues and B lymphocyte purification by immunosorbent methods. CD20 is a non-Ig differentiation antigen of B-cells and its expression is restricted to normal and neoplastic B-cells, being absent from all other leukocytes and tissues. CD20 is expressed by pre B-cells and persists during all stages of B-cell maturation but is lost upon terminal differentiation into plasma cells. Protein passes through the membrane 4 times with both ends in cytoplasm and exposes one short and one longer loop to the external environment. CD20 is not glycosylated in resting B cells and its cytoplasmic domains are differentially phosphorylated upon activation. It acts as a calcium channel involved in B-cell activation and cell cycle progression.

Fournisseur: Biotium

Description: Fibronectin is a dimeric glycoprotein of 440 kDa, which is present in cells, extracellular matrix, and blood. It possesses at least four binding sites for collagen, glycosaminoglycans, transglutaminase, and a cell surface receptor. Fibronectin is involved in cell adhesion, tissue organization, and wound healing. This MAb is directed against the peptide core and reacts with both the plasma and cellular forms of fibronectin. It blocks the fibronectin-medicated cell attachment not by disrupting the collagen-fibronectin interaction, but by interfering with the attachment of fibronectin to its receptor on the cell surface.

Fournisseur: Biotium

Description: This antibody recognizes a protein of 70 kDa, identified as prolactin receptor. Prolactin is a pituitary hormone involved in the stimulation of milk production, salt and water regulation, growth, development and reproduction. The initial step in its action is the binding to a specific membrane receptor (prolactin receptor), which belongs to the superfamily of class 1 cytokine receptors. The function of the prolactin receptor is mediated, at least in part, by two families of signaling molecules: Janus kinases and signal transducers and activators of transcription.

Fournisseur: Biotium

Description: This MAb recognizes a 27 kDa protein, identified as the p27Kip1, a cell cycle regulatory mitotic inhibitor. It is highly specific and shows no cross-reaction with other related mitotic inhibitors. p27Kip1 functions as a negative regulator of G1 progression and has been proposed to function as a possible mediator of TGF- induced G1 arrest. p27Kip1 is a candidate tumor suppressor gene. This MAb is excellent for staining of formalin-fixed tissues.

Fournisseur: Biotium

Description: This MAb recognizes a 27 kDa protein, identified as the p27Kip1, a cell cycle regulatory mitotic inhibitor. It is highly specific and shows no cross-reaction with other related mitotic inhibitors. In Western blotting of cell lysates from 7 human breast cancer cell lines (ZR75-1, ZR75-30, MCF-7, MDAMB453, T47D, CAL51, 734B), the antibody labels a single band corresponding to p27Kip1. It functions as a negative regulator of G1 progression and has been proposed to function as a possible mediator of TGF- induced G1 arrest. p27Kip1 is a candidate tumor suppressor gene. Reportedly, low p27 expression has been associated with unfavorable prognosis in renal cell carcinoma, colon carcinoma, breast carcinomas, non-small-cell lung carcinoma, hepatocellular carcinoma, multiple myeloma, and lymph node metastases in papillary carcinoma of the thyroid, as well as a more aggressive phenotype in carcinoma of the cervix.