Category: monoclonal

Arginase (ARG) is a manganese metalloenzyme that is part of the urea cycle. It catalyses the conversion of L-arginine to L-ornithine and urea. ARG-1 and ARG-2 are the two isoforms of ARG. ARG-1 is a cytosolic enzyme expressed in liver. The ARG-1 antibody is a sensitive marker of hepatic differentiation and is useful in the detection of hepatocytes in normal tissue as well as granulocytes in peripheral blood. For the identification of hepatocellular carcinoma ARG-1 is a sensitive and specific marker.

Bcl6 is a regulatory gene encoding a zinc finger protein. It plays a key role in the formation of the germinal center (GC) and acts as a regulator of B lymphocyte growth and development by protecting GC-B cells from DNA damage-induced apoptosis. Bcl-6 is mainly expressed in GC-B cells. Surrounding mantle-zone and marginal-zone B cells, plasma cells, and progenitor B cells are negative for Bcl-6. The antibody Bcl-6 detects GC cells in lymphoid follicles and a variety of lymphomas including follicular lymphomas, diffuse large B-cell lymphomas (DLBCL) and Burkitt’s lymphomas. In contrast, Bcl-6 is not expressed in hairy cell leukemias, mantle cell or peripheral lymphomas. Bcl-6 is not restricted to the B cell line, but could also be detected in anaplastic large cell lymphoma. Furthermore, Bcl-6 is involved in mammary epithelial differentiation, which could play a potential role in carcinogenesis.

BOB.1 is a lymphoid-specific transcriptional coactivator, which interacts with the transcription factors Oct-1 andOct-2. BOB.1 is expressed in germinal center B-cells, mantle B-cells and plasma cells. It detects a variety of B-cell lymphomas and Hodgkin’s lymphoma.

CD117, also known as c-Kit, encodes a receptor tyrosine kinase that is activated by its ligand stem cell factor (also known as mast cell growth factor). CD117 plays an important role in vital functions, such as homeostasis and melanogenesis. In normal tissues, expression is found in interstitial cells of Cajal, mast cells, melanocytes, various epithelia, testicular and ovarian interstitial cells, neurons of the central nervous system, immature myeloid cells, trophoblastic cells, fetal (but not mature) endothelial cells and fetal (but not mature) basal cells of the skin. CD117 does not occur in smooth muscle cells.
CD117 is a proto-oncogene. Mutations and overexpression are associated with several cancer types, including gastrointestinal stromal tumors (GIST) with 80 95% expression and seminoma with > 90% expression.
CD117 is expressed in around 15-30% of melanomas, although this can vary depending on the type of melanoma. About 30% of lung adenocarcinoma show expression of CD117.

Keratins are cytoplasmic intermediate filament proteins expressed by epithelial cells and their neoplasms. Cytokeratin 20 is a type I keratin mainly found in the gastric and intestinal mucosa. Antibody Cytokeratin 20 is useful in the detection of a variety of adenocarcinomas arising from epithelia, such as colorectal carcinomas, transitional-cell and Merkel cell carcinomas, gastric and pancreatic tumors. CK20 is often used in a panel with antibody Cytokeratin 7.

CD3 is a protein complex that is composed of five chains (gamma, delta, epsilon, zeta, eta) which associate with theT-cell receptor (TCR). CD3 is first expressed in the cytoplasm of developing T-cells, then as they mature it moves to the membrane. CD3e is a membrane protein that plays a role in TCR-CD3 complex assembly and signal transduction regulating T-cell proliferation, apoptosis and thymocyte development. CD3e immunostaining is only seen in T-cells. These predominantly occur in lymphatic organs such as thymus, lymph nodes and tonsils but are regularly also seen – at lower density – in many other tissue types. In malignant lymphomas, CD3 is a pan-T-cell lineage-restricted antigen, detected in 72-95% of the T-cell lymphomas. As B-cell lymphomas are mostly negative forCD3e, the antibody can be used to distinguish between T-cell and B-cell lymphomas.

Keratins are cytoplasmic intermediate filament proteins expressed by epithelial cells. CK6 is a type II keratin constitutively expressed in distinct types of epithelia such as those in oral mucosa, esophagus, papillae of tongue and hair follicle outer root sheath.

CD79a (mb-1) is an integral membrane protein expressed early in B cell maturation and next to CD75b (B29) one of two polypeptide chains of the CD79 molecule.The dimer of CD79a/b has the function to transmit signals to the B cell receptor signaling complex into the cell for induction of B cell activation. The CD79a antibody is used as a marker for identification of normal and neoplastic B lymphocytes.

CD10 (CALLA, neprilysin) is a zinc-dependent metalloprotease enzyme that degrades various bioactive peptides and plays a functional role by modulating cellular responses to peptide substrates. CD10 is a membranous marker with extensive expression in normal tissues. It is reported to be critical for use in diagnosis and subclassification of leukemias (B lymphoblastic leukemia, mixed phenotype acute leukemia, etc.) and lymphomas (follicular lymphoma, Burkitt lymphoma, diffuse large B cell lymphoma, angioimmunoblastic T cell lymphoma, etc.).

Anti-CD10 is found in 60-70% of hepatocellular carcinoma (distinct canalicular pattern), in about 90% of renal cell carcinoma (clear cell and papillary types, but less chromophobic type), in 50-70% of urothelial carcinoma (particularly high grade), and in 60-73% of prostate carcinoma (particularly high grade and aggressive).

Keratins are cytoplasmic intermediate filament proteins expressed by epithelial cells. Cytokeratins, 5 & 6, are type II keratins that are in combination useful in differentiating mesothelioma (positive) from lung carcinoma (negative) or metastic carcinoma in the pleura (negative). It detects undifferentiated large cell carcinoma, squamous carcinoma, spindle cell squamous cell carcinoma of the skin, malignancies of prostate and breast and it helps to discriminate between ductal hyperplasia of the breast (strong staining) and solid papillary DCIS (negative).

CD20 (Cluster of Differentiation 20) is 35/37 kDa non-glycosylated phosphoprotein expressed on the surface of all B-cells. It is involved in B-cell activation, proliferation and differentiation and therefore one of the most importantB-cell markers.

Keratins are cytoplasmic intermediate filament proteins expressed by epithelial cells. Cytokeratin 7 is a type II keratin that is found in most ductal and glandular epithelia including the urinary tract, lung, breast and female genital tract. There is no expression in most gastrointestinal epithelia, prostate, hepatocyte and squamous epithelia, as well as in colon, prostate and squamous carcinomas. Restricted distribution of CK7 makes this antibody a useful marker in a panel with antibody Cytokeratin 20.