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Related to cancer antigen 125: Cancer antigen 15-3, Cancer antigen 19-9


see immunityimmunity,
ability of an organism to resist disease by identifying and destroying foreign substances or organisms. Although all animals have some immune capabilities, little is known about nonmammalian immunity.
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A substance that initiates and mediates the formation of the corresponding immune body, termed antibody. Antigens can also react with formed antibodies. Antigen-antibody reactions serve as host defenses against microorganisms and other foreign bodies, or are used in laboratory tests for detecting the presence of either antigen or antibody. See Antibody, Antigen-antibody reaction

A protein immunogen (any substance capable of inducing an immune response) is usually composed of a large number of antigenic determinants. Thus, immunizing an animal with a protein results in the formation of a number of antibody molecules with different specificities. The antigenicity of a protein is determined by its sequence of amino acids as well as by its conformation. Antigens may be introduced into an animal by ingestion, inhalation, sometimes by contact with skin, or more regularly by injection into the bloodstream, skin, peritoneum, or other body part.

With a few exceptions, such as the autoantigens and the isoantigens of the blood groups, antigens produce antibody only in species other than the ones from which they are derived. All complete proteins are antigenic, as are many bacterial and other polysaccharides, some nucleic acids, and some lipids. Antigenicity may be modified or abolished by chemical treatments, including degradation or enzymatic digestion; it may be notably increased by the incorporation of antigen into oils or other adjuvants. See Isoantigen

Bacteria, viruses, protozoans, and other microorganisms are important sources of antigens. These may be proteins or polysaccharides derived from the outer surfaces of the cell (capsular antigens), from the cell interior (the somatic or O antigens), or from the flagella (the flagellar or H antigens). Other antigens either are excreted by the cell or are released into the medium during cell death and disruption; these include many enzymes and toxins, of which diphtheria, tetanus, and botulinus toxins are important examples. The presence of antibody to one of these constituent antigens in human or animal sera is presumptive evidence of past or present contact with specific microorganisms, and this finds application in clinical diagnosis and epidemiological surveys. See Botulism, Diphtheria, Toxin

Microbial antigens prepared to induce protective antibodies are termed vaccines. They may consist of either attenuated living or killed whole cells, or extracts of these. Since whole microorganisms are complex structures, vaccines may contain 10 or more distinct antigens, of which generally not more than one or two engender a protective antibody. Examples of these are smallpox vaccine, a living attenuated virus; typhoid vaccine, killed bacterial cells; and diphtheria toxoid, detoxified culture fluid. Several independent vaccines may be mixed to give a combined vaccine, and thus reduce the number of injections necessary for immunization, but such mixing can result in a lesser response to each component of the mixture. See Vaccination

Allergens are antigens that induce allergic states in humans or animals. Examples are preparations from poison ivy, cottonseed, or horse dander, or simple chemicals such as formaldehyde or picryl chloride. See Hypersensitivity, Immunology


A substance which reacts with the products of specific humoral or cellular immunity, even those induced by related heterologous immunogens.


a substance that stimulates the production of antibodies
References in periodicals archive ?
Cancer antigen 125: a sensitive marker of ascites in patients with liver cirrhosis.
Serum human chorionic gonadotropin (HCG), Cancer Antigen 125 (CA125), Cancer Antigen 19-9 (CA 19-9), alpha-fetoprotein (AFP) and lactate dehydogenase (LDH) were performed in 82%, 83%, 44%, 52%, 32%, respectively, and they were found to be elevated in 2%, 23%, 7%, 0% and 2% of the tested patients, respectively.
Stender, "Cancer antigen 125 after delivery in women with a normal pregnancy: a prospective cohort study," Acta Obstetricia et Gynecologica Scandinavica, vol.
Levels of cancer antigen 19-9 (CA 19-9) and cancer antigen 125 (CA-125) were within normal limits.
Aims: To explore the efficacy of human epididymis 4 (HE 4) and cancer antigen 125 (CA 125) markers in differentiating malignant and benign pelvic masses of ovarian origin and to identify the cut-off points for those markers.
in 1990, is calculated based on ultrasound findings, serum levels of tumor marker cancer antigen 125 (CA125), and menopausal status [1].
Serum cancer antigen 125 (CA125) [9] is a glycoprotein serum biomarker used to diagnose and monitor epithelial ovarian cancer (EOC), especially its most common and malignant variant high-grade serous ovarian cancer (1).
Currently, the standard tools for detecting ovarian cancer are pelvic ultrasonography and measuring serum cancer antigen 125 (also called carbohydrate antigen 125; CA-125) levels, which could be combined with the menopausal status to calculate the risk malignancy index (RMI) and is considered a simple and affordable test.
If it has the characteristics of cancer, a blood test that measures the amount of cancer antigen 125 (CA-125) may be ordered.
Abbreviations AUC: Area Under The Curve BOD: Benign Ovarian Diseases CA125: Cancer Antigen 125 CI: Confidence Interval EOC: Epithelial Ovarian Cancer FIGO: International Federation of Obstetricians and Gynaecologists GLYCOV: Glycan-Based Biomarker Developed by The Authors to Diagnose Ovarian Cancer MALDI-TOF: Matrix-Assisted Laser Desorption Ionization Time-of-Flight PNGase F: Peptide-N4-(N-Acetyl-[beta]-glucosaminyl) Asparagine Amidase F ROC: Receiver Operating Characteristic.
CA125 (cancer antigen 125, mucin 16), the protein classified as a family of mucin member, has been intensively studied because of its wide use in clinical practice as tumor marker.
The serum levels of cancer antigen 125 (CA-125) and interleukin 18(IL-18) in the peritoneal fluids were detected using enzyme-linked immune-sorbent assay.