16369 Results for: "Biotium"

Supplier: Biotium

Recognizes a protein of 205 kDa-220 kDa, identified as CD45RA. CD45RA is isoforms of the human leukocyte common antigen (CD45). Human CD45 contains three exons which encode peptide segments designated A, B and C, respectively. The differential splicing of the exons generates at least five isoforms, ABC, AB, BC, B and O. This antibody reacts with ABC and BC isoforms. CD45RA is expressed on 40-50% of peripheral CD4 T-cells, 50% of peripheral CD8 T-cells, B-cells, and leukemic B-cell lines. T-cells expressing CD45RA are naive or virgin T-cells. T-cells expressing CD45RO are memory T-cells. CD45RA and CD45RO define complementary, predominantly non-overlapping populations of resting peripheral T-cells. This MAb is useful in study on the subpopulation of CD4 or CD8 T-cells. It can especially be used to differentiate T-cell lymphomas (CD45RO ve) from B cell lymphomas (CD45RA ve).

Supplier: Biotium

Chromogranin A is present in neuroendocrine cells throughout the body, including the neuroendocrine cells of the large and small intestine, adrenal medulla and pancreatic islets. It is an excellent marker for carcinoid tumors, pheochromocytomas, paragangliomas, and other neuroendocrine tumors. Co-expression of chromogranin A and neuron specific enolase (NSE) is common in neuroendocrine neoplasms. Reportedly, co-expression of certain keratins and chromogranin indicates neuroendocrine lineage. The presence of strong anti-chromogranin staining and absence of anti-keratin staining should raise the possibility of paraganglioma. The co-expression of chromogranin and NSE is typical of neuroendocrine neoplasms. Most pituitary adenomas and prolactinomas readily express chromogranin.

Supplier: Biotium

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.

Supplier: Biotium

This antibody recognizes a 63 kDa protein, which is identified as TOX3. It contains a high mobility group (HMG)-box, which regulates Ca2 -dependent transcription in neurons through interaction with the cAMP-response-element-binding protein (CREB). TOX3 appears to be associated with breast cancer susceptibility and is expressed downstream of a cytoprotective cascade together with CITED1, a transcriptional regulator that does not bind directly to DNA. TOX3 is predominantly expressed in the brain and forms homodimers. TOX3 overexpression protects neuronal cells from cell death caused by endoplasmic reticulum stress or BAX overexpression through the induction of anti-apoptotic transcripts and repression of pro-apoptotic transcripts.

Supplier: Biotium

By immunohistochemistry, this antibodyspecifically recognizes a protein in melanocytes and melanomas. This MAb reacts with junctional and blue nevus cells and variably with fetal and neonatal melanocytes. Intradermal nevi, normal adult melanocytes, and non-melanocytic cells are negative. It does not stain tumor cells of epithelial, lymphoid, glial, or mesenchymal origin. Metastatic amelanotic melanoma can often be confused with a variety of poorly differentiated carcinomas, large cell lymphomas, and sarcomas using H & E stains alone. It is also difficult to differentiate melanoma from spindle cell carcinomas and various types of mesenchymal neoplasms. This MAb stains fetal and neonatal melanocytes, junctional and blue nevus cells, and malignant melanoma. This MAb also stains Angiomyolipoma (PEComa).

Supplier: Biotium

CD2 interacts through its amino-terminal domain with the extracellular domain of CD58 (also designated CD2 ligand) to mediate cell adhesion. CD2/CD58 binding can enhance antigen-specific T cell activation. CD2 is a transmembrane glycoprotein that is expressed on peripheral blood T lymphocytes, NK cells and thymocytes. CD58 is a heavily glycosylated protein with a broad tissue distribution in hematopoietic and other cells, including endothelium. Interaction between CD2 and its counter receptor LFA3 (CD58) on opposing cells optimizes immune system recognition, thereby facilitating communication between helper T lymphocytes and antigen-presenting cells, as well as between cytolytic effectors and target cells.

Supplier: Biotium

This is a cocktail of four highly specific monoclonal antibodies (EGP40/826, EGP40/837, EGP40/1110, EGP40/1120) that recognize extracellular as well as intracellular domains of the epithelial cellular adhesion molecule (Ep-CAM). It is a 40-43 kDa transmembrane epithelial glycoprotein, identified as epithelial specific antigen (ESA), or Ep-CAM. Ep-CAM is expressed on baso-lateral cell surface in most simple epithelia and a vast majority of carcinomas. This epithelial antigen plays an important role as a tumor-cell marker in lymph nodes from patients with esophageal carcinoma otherwise classified as node-negative. Epithelial antigen has also been suggested as a discriminator between basal cell and baso-squamous carcinomas, and squamous cell carcinoma of the skin.

Supplier: Biotium

Highly cross-adsorbed goat anti-rat IgG (H L) secondary antibody labeled with our superior CF® dyes.

Supplier: Biotium

Recognizes a 53 kDa protein, which is identified as p53 suppressor gene product. It reacts with the mutant as well as the wild form of p53 under denaturing and non-denaturing conditions. Its epitope maps within the N-terminus (aa 20-25) of p53 oncoprotein. p53 is a tumor suppressor gene expressed in a wide variety of tissue types and is involved in regulating cell growth, replication, and apoptosis. It binds to MDM2, SV40 T antigen and human papilloma virus E6 protein. Positive nuclear staining with p53 antibody has been reported to be a negative prognostic factor in breast carcinoma, lung carcinoma, colorectal, and urothelial carcinoma. Anti-p53 positivity has also been used to differentiate uterine serous carcinoma from endometrioid carcinoma as well as to detect intratubular germ cell neoplasia. Mutations involving p53 are found in a wide variety of malignant tumors, including breast, ovarian, bladder, colon, lung, and melanoma.

Supplier: Biotium

Recognizes an oncofetal antigen of 220 kDa, identified as a tumor-associated glycoprotein (TAG-72) with properties of a mucin. This MAb defines the mucin-carried sialylated-Tn epitope. TAG-72 is usually expressed by adenocarcinomas, but is negative in mesotheliomas. Studies have reported that this antibody has 80% sensitivity and 93% specificity for pulmonary adenocarcinoma. Therefore, TAG-72 is a useful marker to distinguish between mesothelioma and adenocarcinoma. However, false positive reactions can occur so results must be interpreted with the utmost caution. This antibody may be useful in the differentiation of non-small cell carcinomas from small cell carcinomas of the lung. The combined use of anti-TAG-72 and anti-GCDFP-15 is valuable in the diagnosis of apocrine carcinoma.

Supplier: Biotium

Expression of DOG-1 protein is elevated in the gastrointestinal stromal tumors (GISTs), c-kit signaling-driven mesenchymal tumors of the GI tract. DOG-1 is rarely expressed in other soft tissue tumors, which, due to appearance, may be difficult to diagnose. Immunoreactivity for DOG-1 has been reported in 97.8 percent of scorable GISTs, including all c-kit negative GISTs. Overexpression of DOG-1 has been suggested to aid in the identification of GISTs, including Platelet-Derived Growth Factor Receptor Alpha mutants that fail to express c-kit antigen. The overall sensitivity of DOG1 and c-kit in GISTs is nearly identical: 94.4% vs. 94.7%.

Supplier: Biotium

Recognizes an oncofetal antigen of 220 kDa, identified as a tumor-associated glycoprotein (TAG-72) with properties of a mucin. This MAb defines the mucin-carried sialylated-Tn epitope. TAG-72 is usually expressed by adenocarcinomas, but is negative in mesotheliomas. Studies have reported that this antibody has 80% sensitivity and 93% specificity for pulmonary adenocarcinoma. Therefore, TAG-72 is a useful marker to distinguish between mesothelioma and adenocarcinoma. However, false positive reactions can occur so results must be interpreted with the utmost caution. This antibody may be useful in the differentiation of non-small cell carcinomas from small cell carcinomas of the lung. The combined use of anti-TAG-72 and anti-GCDFP-15 is valuable in the diagnosis of apocrine carcinoma.

Supplier: Biotium

This antibody cocktail recognizes three melanoma-specific proteins, which include MART-1, Tyrosinase and gp100. MART-1 is a newly identified melanocyte differentiation antigen recognized by autologous cytotoxic T lymphocytes. Tyrosinase is one of the targets for cytotoxic T-cell recognition in melanoma patients. Function of gp100 is not known but it is reported to be a useful marker for melanocytes and melanomas. This cocktail of three markers is designed for extremely sensitive labeling of formalin-fixed, paraffin-embedded melanomas and other tumors showing melanocytic differentiation.

Supplier: Biotium

This MAb is specific to kappa light chain of immunoglobulin and shows no cross-reaction with lambda light chain or any of the five heavy chains. In mammals, the two light chains in an antibody are always identical, with only one type of light chain, kappa or lambda. The ratio of Kappa to Lambda is 70:30. However, with the occurrence of multiple myeloma or other B-cell malignancies this ratio is disturbed. Antibody to the kappa light chain is reportedly useful in the identification of leukemias, plasmacytomas, and certain non-Hodgkin's lymphomas. Demonstration of clonality in lymphoid infiltrates indicates that the infiltrate is malignant.

Supplier: Biotium

This MAb recognizes an epitope within the 74-182 C-terminal sequence (11kD peptide fragment) of human serum Cellular Retinol Binding Protein 1 (CRBP 1), a single-chain glycoprotein belonging to the superfamily of hydrophobic molecule transporter proteins, which is responsible for transport of retinol (vitamin A1) from the liver to peripheral target tissues, like the eye, where it mediates the cellular uptake. CRBP 1 is synthesized by hepatic parenchymal cells where it becomes bound to its ligand retinol and is then released into the circulation, where it binds further to the protein transthyretin, to form a transporting complex, which is big enough not to be lost by filtration through the kidney glomeruli. It is detected in nearly all tissues with higher expression in adult ovary, pancreas, pituitary gland, adrenal gland, and fetal liver.

Supplier: Biotium

Recognizes a protein of 12 kDa, identified as β-microglobulin. β-microglobulin non-covalently associates with the 44 kDa chain to form the HLA Class I antigen complex. Human β-2 microglobulin associated with HLA Class I antigens is expressed on many types of cells including lymphocytes, thymocytes, monocytes, granulocytes, platelets, endothelial cells, and epithelial cells. It is absent on erythrocytes. This MAb is specific to human β-2 microglobulin and does not react with non-human primate cells. This antibody reacts with all cell types excluding erythrocytes. The detection of β-2 microglobulin in body fluids has been used as a tumor marker and for monitoring patients with HIV infection.

Supplier: Biotium

Chromogranin A is present in neuroendocrine cells throughout the body, including the neuroendocrine cells of the large and small intestine, adrenal medulla and pancreatic islets. It is an excellent marker for carcinoid tumors, pheochromocytomas, paragangliomas, and other neuroendocrine tumors. Co-expression of chromogranin A and neuron specific enolase (NSE) is common in neuroendocrine neoplasms. Reportedly, co-expression of certain keratins and chromogranin indicates neuroendocrine lineage. The presence of strong anti-chromogranin staining and absence of anti-keratin staining should raise the possibility of paraganglioma. The co-expression of chromogranin and NSE is typical of neuroendocrine neoplasms. Most pituitary adenomas and prolactinomas readily express chromogranin.

Supplier: Biotium

CD31 (PECAM-1) is a transmembrane glycoprotein member of the immunoglobulin supergene family of adhesion molecules. CD31 is expressed by stem cells of the hematopoietic system and is primarily used to identify and concentrate these cells for experimental studies as well as for bone marrow transplantation. Anti-CD31 has shown to be highly specific and sensitive for vascular endothelial cells. Staining of nonvascular tumors (excluding hematopoietic neoplasms) is rare. CD31 MAb reacts with normal, benign, and malignant endothelial cells which make up blood vessel lining. The level of CD31 expression can help to determine the degree of tumor angiogenesis, and a high level of CD31 expression may imply a rapidly growing tumor and potentially a predictor of tumor recurrence.

Supplier: Biotium

Cytokeratin 8 (CK8) belongs to the type II (or B or basic) subfamily of high molecular weight cytokeratins and exists in combination with cytokeratin 18 (CK18). This MAb cocktail recognizes all simple epithelia including glandular epithelium, for example thyroid, female breast, gastrointestinal tract, respiratory tract, and urogenital tract including transitional epithelium. All adenocarcinomas and most squamous carcinomas are positive but keratinizing squamous carcinomas are usually negative. This antibody is useful in demonstrating the presence of Paget cells; there is very little keratin 18 in the normal epidermis so only Paget cells are stained.Immunohistochemical staining with this MAb is indistinguishable from that obtained with monoclonal antibody 5D3.

Supplier: Biotium

S100 belongs to the family of calcium binding proteins. S100A and S100B proteins are two members of the S100 family. S100A is composed of an alpha and beta chain whereas S100B is composed of two beta chains. S-100 protein has been found in normal melanocytes, Langerhans cells, histiocytes, chondrocytes, lipocytes, skeletal and cardiac muscle, Schwann cells, epithelial and myoepithelial cells of the breast, salivary and sweat glands, as well as in glial cells. Neoplasms derived from these cells also express S-100 protein, albeit non-uniformly. A large number of well-differentiated tumors of the salivary gland, adipose and cartilaginous tissue, and Schwann cell-derived tumors express S-100 protein. Almost all malignant melanomas and cases of histiocytosis X are positive for S-100 protein. Despite the fact that S-100 protein is an ubiquitous substance, its demonstration is of great value in the identification of several neoplasms, particularly melanomas and their metastases.

Supplier: Biotium

Myogenin is a member of the MyoD family of myogenic basic helix-loop-helix (bHLH) transcription factors that also includes MyoD, Myf-5, and MRF4 (also known as herculinor Myf-6). MyoD family members are expressed exclusively in skeletal muscle and play a key role in activating myogenesis by binding to enhancer sequences of muscle-specific genes. The regulatory domain of MyoD is approximately 70 amino acids in length and includes both a basic DNA binding motif and a bHLH dimerization motif. MyoD family members share about 80% amino acid homology in their bHLH motifs. Anti-myogenin labels the nuclei of myoblasts in developing muscle tissue, and is expressed in tumor cell nuclei of rhabdomyosarcoma and some leiomyosarcomas. Positive nuclear staining may occur in Wilms' tumor.

Supplier: Biotium

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. TNF alpha is currently being evaluated in treatment of certain cancers and AIDS Related Complex.

Supplier: Biotium

Myogenin is a member of the MyoD family of myogenic basic helix-loop-helix (bHLH) transcription factors that also includes MyoD, Myf-5, and MRF4 (also known as herculinor Myf-6). MyoD family members are expressed exclusively in skeletal muscle and play a key role in activating myogenesis by binding to enhancer sequences of muscle-specific genes. The regulatory domain of MyoD is approximately 70 amino acids in length and includes both a basic DNA binding motif and a bHLH dimerization motif. MyoD family members share about 80% amino acid homology in their bHLH motifs. Anti-myogenin labels the nuclei of myoblasts in developing muscle tissue, and is expressed in tumor cell nuclei of rhabdomyosarcoma and some leiomyosarcomas. Positive nuclear staining may occur in Wilms' tumor.

Supplier: Biotium

Reacts with a 70 kDa membrane-bound isozyme (Regan and Nagao type) of Placental Alkaline Phosphatase (PLAP) occurring in the placenta during the 3rd trimester of gestation. It is highly specific for PLAP and shows no cross-reaction with other isozymes of alkaline phosphatase. Anti-PLAP reacts with germ cell tumors and can discriminate between these and other neoplasms. Somatic neoplasms e.g. breast, gastrointestinal, prostatic, and urinary cancers may also immunoreact with antibodies to PLAP. Anti-PLAP positivity in conjunction with anti-keratin negativity favors seminoma over carcinoma. Germ cell tumors are usually anti-keratin positive, but they regularly fail to stain with anti-EMA, whereas most carcinomas stain with anti-EMA. Anti-PLAP has been useful in the diagnosis of gestational trophoblastic disease.

Supplier: Biotium

This antibody recognizes a protein of 36 kDa, identified as Thymidylate Synthase (TS) (EC 2.1.1.45). TS converts deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP), which is essential for DNA biosynthesis. TS is also a critical target for the fluoropyrimidines, an important group of antineoplastic drugs that are widely used in the treatment of solid tumors. Both 5-FU and fluorodeoxyuridine are converted in tumor cells to FdUMP which inactivates TS by formation of a ternary covalent complex in the presence of the folate cofactor 5,10-methylenetetrahydrofolate. Expression of TS protein is associated with response to 5-fluorouracil (5-FU) in human colorectal, gastric, head and neck, and breast carcinomas.

Supplier: Biotium

MITF (microphthalmia transcription factor) is a basic helix-loop-helix-leucine-zipper (bHLH-Zip) transcription factor that regulates the development and survival of melanocytes and retinal pigment epithelium, and also is involved in transcription of pigmentation enzyme genes such as tyrosinase TRP1 and TRP2. MITF has been shown to be phosphorylated by MAP kinase in response to c-kit activation, resulting in upregulation of MITF transcriptional activity. Mutations of the MITF gene are associated with the autosomal dominant hereditary deafness and pigmentation condition, Waardenburg Syndrome type 2A. Multiple isoforms of MITF exist, including MITF-A, MITF-B, MITF-C, MITF-H, and MITF-M, which differ in the amino-terminal domain and in their expression patterns. The MITF-M isoform is restricted to the melanocyte cell lineage. This MAb recognizes a nuclear protein, which is expressed in the majority of primary and metastatic epithelioid malignant melanomas as well as in normal melanocytes, benign nevi and dysplastic nevi.

Supplier: Biotium

CD309, also known as VEGFR2, KDR3, and Flk-1 (mouse), is a type I transmembrane glycoprotein. It is a member of the CSF-1/PDGF receptor family of type III tyrosine kinase receptors. Human VEGFR2 is mainly expressed by endothelial cells, embryonic tissues, and megakaryocytes. It plays an important role in the regulation of angiogenesis, vasculogenesis, and vascular permeability. The ligands of VEGFR2 include VEGF-A, VEGF-C, VEGF-D, and VEGF splice isoforms. Ligation of VEGFR2 with its ligands results in the receptor dimerization and auto-phosphorylation, stimulating endothelial cell proliferation and migration.

Supplier: Biotium

This MAb reacts with an extracellular domain (close to transmembrane) of CD56/NCAM. Three isoforms of neural cell adhesion molecule (NCAM) are produced by differential splicing of the RNA transcript from a single gene. The 135 kDa isoform is the basic molecule, which is glycosylated or sialylated to produce the mature species. Anti-CD56 recognizes two proteins of the neural cell adhesion molecule, the basic molecule expressed on most neuroectodermally derived tissues and neoplasms (e.g. retinoblastoma, medulloblastomas, astrocytomas, neuroblastomas, and small cell carcinomas). It is also expressed on some mesodermally derived tumors (rhabdomyosarcoma). Anti-CD56 plays an important role in the diagnosis of nodal and nasal NK/T-cell lymphomas.

Supplier: Biotium

CD309, also known as VEGFR2, KDR3, and Flk-1 (mouse), is a type I transmembrane glycoprotein. It is a member of the CSF-1/PDGF receptor family of type III tyrosine kinase receptors. Human VEGFR2 is mainly expressed by endothelial cells, embryonic tissues, and megakaryocytes. It plays an important role in the regulation of angiogenesis, vasculogenesis, and vascular permeability. The ligands of VEGFR2 include VEGF-A, VEGF-C, VEGF-D, and VEGF splice isoforms. Ligation of VEGFR2 with its ligands results in the receptor dimerization and auto-phosphorylation, stimulating endothelial cell proliferation and migration.

Supplier: Biotium

This MAb recognizes a single chain, transmembrane, heavily glycosylated protein of 90-120 kDa, which is identified as CD34. Its expression is a hallmark for identifying pluripotent hematopoietic stem or progenitor cells. Its expression is gradually lost as lineage committed progenitors differentiate. CD34 is a marker of choice for staining blasts in acute myeloid leukemia. In addition, CD34 is expressed by soft tissue tumors, such as solitary fibrous tumor and gastrointestinal stromal tumor. Its expression is also found in vascular endothelium. Additionally, it appears that proliferating endothelial cells express this molecule more than the non-proliferating endothelial cells. Anti-CD34 labels > 85% of angiosarcoma and Kaposi's sarcoma, but with a lower specificity.