"Biotium"

Supplier: Biotium

DNA topoisomerases are nuclear enzymes that regulate the topological structure of DNA in eukaryotic cells by transiently breaking and rejoining DNA strands. Due to their roles in DNA replication, recombination, and transcription, DNA topoisomerases have been identified as targets of numerous anticancer drugs. Mitochondrial Topo I (DNA topoisomerase I, mitochondrial) is a 601 amino acid protein that primarily acts to relieve DNA strain that may occur during duplication of mitochondrial DNA. As a type IB topoisomerase, mitochondrial Topo I requires a divalent metal, either, calcium or magnesium, as well as an alkaline pH for optimal activity.

Supplier: Biotium

Recognizes a 67 kDa transmembrane protein, which is identified as CD5. The CD5 antigen is found on 95% of thymocytes and 72% of peripheral blood lymphocytes. In lymph nodes, the main reactivity is observed in T cell areas. Anti-CD5 is a pan T-cell marker that also reacts with a range of neoplastic B-cells, e.g. chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), mantle cell lymphoma, and a subset (~10%) of diffuse large B-cell lymphoma. CD5 aberrant expression is useful in making a diagnosis of mature T-cell neoplasms. Anti-CD5 detection is diagnostic in CLL/SLL within a panel of other B-cell markers, especially one that includes anti-CD23. Anti-CD5 is also very useful in differentiating among mature small lymphoid cell malignancies. In addition, anti-CD5 can be used in distinguishing thymic carcinoma ( ) from thymoma (-). Anti-CD5 does not react with granulocytes or monocytes.

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

Recognizes a protein of 18-35 kDa, identified as CD90 (also known as Thy1). CD90 is a member of the immunoglobulin superfamily. It may contribute to inhibition of proliferation/differentiation of hematopoietic stem cells and neuron memory formation in the CNS. It consists of a single Ig domain (112 amino acids; 25-35 kDa) inserted into the cell membrane via a GPI anchor. Expressed by hematopoietic stem cells and neurons in all species studied. Its highly expressed in connective tissue and various fibroblast and stromal cell lines, expressed on all thymocytes and peripheral T cells in mice, but in humans expressed only on small % fetal thymocytes, 10-40% of CD34 cells in bone marrow, and <1% of CD3 CD4 lymphocytes in peripheral circulation. It is also expressed by human lymph node HEV endothelium but not other endothelia. Lastly, it is expressed by a limited number of lymphoblastoid and leukemic cell lines.

Supplier: Biotium

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.

Supplier: Biotium

This MAb reacts with a membrane-associated protein present in normal and malignant neuroendocrine tissues including small cell lung cancer (SCLC). It stains neural and a variable number of endocrine tissues and in the lung it reacts preferentially with SCLC and carcinoids. Its epitope is destroyed during formalin fixation. This antibody was categorized during the First International Workshop on Small Cell Lung Cancer Antigens held in London in April 1987. There are two major types of Lung Carcinoma: non-small cell, which accounts for 80% of all cases; and small cell, which accounts for roughly 20% of all lung cancers reported. The lung continues to be a customary place for cancer migration from tumors elsewhere in the body. Treatment depends on the specific cell type of the cancer, level of progression and status of the individual patient.

Supplier: Biotium

This antibody recognizes a protein of 25-26 kDa, identified as the bcl-2 α oncoprotein. It shows no cross-reaction with Bcl-x or Bax protein. Expression of bcl-2 α oncoprotein inhibits the programmed cell death (apoptosis). In most follicular lymphomas, neoplastic germinal centers express high levels of bcl-2 α protein, whereas the normal or hyperplastic germinal centers are negative. Consequently, this antibody is valuable when distinguishing between reactive and neoplastic follicular proliferation in lymph node biopsies. It may also be used in distinguishing between those follicular lymphomas that express bcl-2 protein and the small number in which the neoplastic cells are bcl-2 negative.

Supplier: Biotium

This antibody recognizes a transcription factor of 64-67 kDa, identified as c-myc. Its epitope spans between aa 410-419 (EQKLISEEDL) which is a specific portion of an alpha helical region of human c-myc protein. This MAb shows no cross-reaction with v-myc. c-myc is involved in the control of cell proliferation and differentiation and is amplified and/or overexpressed in a variety of tumors. Over-expression of c-myc protein occurs frequently in luminal cells of prostate intraepithelial neoplasia as well as in most primary carcinomas and metastatic disease.

Supplier: Biotium

CD45R, also designated CD45 and PTPRC, has been identified as a transmembrane glycoprotein, broadly expressed among hematopoietic cells. Multiple isoforms of CD45R are distributed throughout the immune system according to cell type. These isoforms arise because of alternative splicing of exons 4, 5, and 6. The corresponding protein domains are characterized by the binding of monoclonal antibodies specific for CD45RA (exon 4), CD45RB (exon 5), CD45RC (exon 6) and CD45RO (exons 4 to 6 spliced out). The variation in these isoforms is localized to the extracellular domain of CD45R, while the intracellular domain is conserved. CD45R functions as a phosphor-tyrosine phosphatase. Antibody to CD45 is useful in differential diagnosis of lymphoid tumors from non-hematopoietic undifferentiated neoplasms.

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 MAb recognizes a single chain, transmembrane, heavily glycosylated protein of 90-120 kDa, which is identified as CD34. On the basis of differential sensitivity to degradation by specific enzymes, epitopes of monoclonal antibodies to CD34 are classified intothree main categories, class I, class II and class III. It is a class II antibody whose epitope is resistant to neuraminidase but sensitive to glycoprotease and chymopapain.CD34 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.

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

Recognizes a protein of 55 kDa, identified as CD14 (also known lipopolysaccharide receptor). CD14 is expressed strongly on monocytes and macrophage and weakly on the surface of neutrophils. CD14 is anchored to cells by linkage to glycosylphosphatidylinositol (GPI) and functions as a high affinity receptor for complexes of LPS and LPS binding protein (LBP). Soluble CD14, also binding to LPS, acts at physiological concentration as an LPS agonist and has, at higher concentrations, an LPS antagonizing effect in cell activation.

Supplier: Biotium

Recognizes a single glycoprotein of 520 kDa, identified as mucin 2 (MUC2). This MAb shows no cross-reaction with human milk fat globule membranes, MUC1, or MUC3. Mucins are high molecular weight glycoproteins, which constitute the major component of the mucus layer that protects the gastric epithelium.MUC2 is specifically expressed in goblet cells of the small intestine & colon; in about 65% of colonic carcinomas and about 40% of gastric carcinomas. MUC2 is rarely expressed outside of the GI tract with the exceptions of mucinous carcinoma of breast and clear cell-type carcinomas of the ovary.

Supplier: Biotium

Actin is a major component of the cytoskeleton and is present in most cell types. It is highly specific to actin from smooth muscles. This MAb does not stain cardiac or skeletal muscle; however, it does stain myofibroblasts and myoepithelial cells. This antibody could be used together with anti-muscle specific actin and myogenin in making a diagnosis of smooth muscle and skeletal muscle tumors. In most cases of rhabdomyosarcoma, this antibody yields negative results whereas anti-muscle specific actin and myogenin are positive. Leiomyosarcomas are positive only with anti-muscle specific actin and anti-smooth muscle actin and are negative with anti-myogenin.

Supplier: Biotium

PAb122 binds to the C-terminus (aa370-378) of both wild type and mutated p53. When microinjected into nuclei, PAb122 blocked re-entry into the S-phase of the cell cycle. Mutation and/or allelic loss of p53 is one of the causes of a variety of mesenchymal and epithelial tumors. If it occurs in the germ line, such tumors run in families. p53 Binds to a DNA consensus sequence, the p53 response element, and it regulates normal cell growth cycle events by activating transcription of genes, involved either in progression through the cycle, or causing arrest in G1 when the genome is damaged. In most transformed and tumor cells the concentration of p53 is increased 51000 fold over the minute concentrations (1000 molecules cell) in normal cells, principally due to the increased half-life (4 h) compared to that of the wild-type (20 min). p53 Localizes in the nucleus, but is detectable at the plasma membrane during mitosis and when certain mutations modulate cytoplasmic/nuclear distribution. p53 Is the most commonly mutated gene in spontaneously occurring human cancers. Mutations arise with an average frequency of 70% but incidence varies from zero in carcinoid lung tumors to 97% in primary melanomas. High concentrations of p53 protein are transiently expressed in human epidermis and superficial dermal fibroblasts following mild ultraviolet irradiation.