دسته: مونوکلونال

GATA3 is a zinc finger protein regulating as transcription factor the development of various tissues and cell types, including early T cell development and development of mammary gland. Expression is found in breast epithelium, urothelial cells, and a subset of lymphocytes. Anti-GATA3may be used for identification of breast carcinoma or urothelial carcinoma.

Desmin is a muscle-specific intermediate filament protein type III and is found in the dense bodies of smooth muscle cells and in the Z-disk of striated muscles. Desmin connects the contractile apparatus to the subsarcolemmal cytoskeleton and organelles like nuclei. It also forms a scaffold around the myofibrillar Z-disk. It is useful in the detection of tumors with myoid origin and to differentiate mesothelioma from carcinoma.

Epidermal growth factor is a growth factor that stimulates cell growth, proliferation, and differentiation by binding to its receptor EGFR. EGFR is a receptor tyrosine kinase activating several signaling cascades. It is ubiquitously expressed and observed in tumors of head and neck, brain, bladder, stomach, breast, lung, endometrium, cervix, vulva, ovary, esophagus, stomach, and in squamous cell carcinoma. Overexpression of EGFR in tumors indicates poor prognosis.

Factor XIII is activated in the blood coagulation cascade by thrombin and calcium to a transglutaminase stabilizing the fibrin clot. This antibody detects the coagulation factor XIIIa subunit. Defects in factor XIIIa cause factor XIII subunit a deficiency an autosomal recessive disorder characterized by a lifelong bleeding tendency, defective wound healing, and habitual abortion.

Glial fibrillary acidic protein is an intermediate filament protein that is expressed by numerous cell types of the central nervous system. In the central nervous system, GFAP is expressed in astrocytes and ependymal cells but not in other glial cells. However, immature oligodendrocytes and immature choroid plexus cells may be GFAP positive. In the peripheral nervous system enteric Schwann cells and satellite cells of human sensory ganglia express GFAP. Outside the nervous system, GFAP is seen in myoepithelial cells and chondroblasts, in the former coexpressed with cytokeratin, in the latter coexpressed with vimentin. Astrocytoma, ependymoma, glioblastoma, and oligodendroglioma are almost always positive. Plexus carcinoma, ganglioglioma and primitive neuroectodermal tumours (PNET: neuroblastoma a.o.) express GFAP to a varying extent. Schwannoma and neurofibroma frequently express GFAP. Chondroma, chondrosarcoma and pleomorphic adenoma are also GFAP positive in most cases. A few carcinomas (especially from lung and breast) may express GFAP. in paraganglioma GFAP may be detected in sustentacular cells. This marker is mainly used to distinguish neoplasms of astrocytic origin from other neoplasms in the central nervous system.

Glutamine synthetase (GS) converts ammonia and glutamate to glutamine. Glutamine synthetase has multiple metabolic functions. Two of them are detoxification of ammonia, and regulation of glutamate in neurons. Synthesis and catalytic activity of glutamine synthetase are highly regulated.

Her2/Neu is a member of human epidermal growth factor family and encodes for a receptor tyrosine kinase involved in signal paths of growth factors.
Her2/Neu activation occurs in various tumors, mostly through gene amplification which results in high level overexpression. Her2/Neu amplification and overexpression is particularly common in breast cancer but can – at lower frequency – also occur in many other tumor entities. Numerous studies have demonstrated the prognostic relevance of Her2/Neu, which is overexpressed in 10% to 40% of human breast tumors.

HSP70 is a heat shock protein of 70kDa. It prevents aggregation of other proteins in conjunction with other heat shock proteins and mediates folding of new proteins during synthesis.

Helicobacter pylori (H. pylori) is a spiral-shaped, gram negative rod bacterium that is found in human stomach, despite there is an extreme acidic pH. Infections of gastric mucosa lead to gastric diseases like stomach ulcers or chronic gastritis. Furthermore, an infection with H. pylori is linked with the formation of gastric cancer and MALT lymphoma (MALT = Mucosa Associated Lymphoid Tissue). The antibody is useful for detecting the bacterial infection in gastric and duodenal epithelial cells.

Inhibin down regulates FSH synthesis and inhibits FSH secretion. This antibody recognizes a protein of 32 kDa which is identified as Inhibin alpha. It helps in the differentiation between adrenal cortical tumors and renal cell carcinoma and it detects sex cord stromal tumors of the ovary as well as trophoblastc tumors.

Immunoglobulin G is the most abundant antibody isotype found in the circulation. Human IgG4, one of four subclasses of IgG, contains a gamma 4 heavy chain and a hinge region that is shorter than that of IgG1. The two primary effector functions are activating complements and binding to the FcgR of effector cells to initiate phagocytosis. Human IgG4 accounts for less than 6 % of the total IgG serum level. IgG4-related sclerosing disease has been recognized as a systemic disease entity characterized by an elevated serum IgG4 level, sclerosing fibrosis, and diffuse lympho-plasmacytic infiltration with the presence of many IgG4-positive plasma cells. IgG4 is overexpressed in inflammatory pseudo-tumor (IPT) and under expressed in inflammatory myofibroblastic tumor (IMT). In pulmonary nodular lymphoid hyperplasia (PNLH), there are an increased number of IgG4+ plasma cells.

DNA mismatch repair (MMR) system consists of four major proteins called MLH1, MSH2, MSH6, and PMS2. These proteins work two by two, MLH1 with PMS2 and MSH2 with MSH6. Loss of function of one of the four proteins leads to inactivation of the MMR system, resulting in a loss of fidelity of the replication and an accumulation of mutations thereby leading to microsatellite instability (MSI).
MSI is associated with hereditary nonpolyposis colorectal cancer (HNPCC, Lynch syndrome), which is characterized by the development of colorectal cancer, endometrial cancer and various other tumors at early age.
Loss of MLH1 function due to gene mutation or epigenetic changes is characterized by absence of nuclear expression in neoplastic cells, whereas intact nuclear MLH1 expression indicates normal MLH1 function and no gene mutations. MLH1 is normally expressed in most cases of sporadic colorectal cancer, loss of MLH1 expression is found in 30-40%.
Anti-MLH1 is useful in detection of MSI, especially in a panel with MSH6 (QR011), PMS2 (QR009) and MSH2 (QR010).