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Index Antigen

In immunology, an antigen is a molecule capable of inducing an immune response (to produce an antibody) in the host organism. [1]

95 relations: Adaptive immune system, Adduct, Adjuvant, Allele, Allergen, Allergy, Allotype (immunology), Antibody, Antigen, Antigen-presenting cell, Antigenic escape, Antitoxin, Apoptosis, Autoimmune disease, Autoimmunity, Autotransplantation, B cell, B-cell receptor, Bacteria, CD4, Central tolerance, Cervical cancer, Complementarity-determining region, Conformational epitope, Cross-reactivity, Cytokine, Cytotoxic T cell, Endocytosis, Endoplasmic reticulum, Epitope, Exome, Fragment antigen-binding, Genome, Hapten, Head and neck cancer, Homeostasis, Host (biology), Idiotopes, Idiotype, Immune response, Immune system, Immunogen, Immunogenicity, Immunology, Infection, Ingestion, Inhalation, Injection (medicine), László Detre (microbiologist), Linear epitope, ..., Lipid, Lysis, Macrophage, Magnetic immunoassay, Major histocompatibility complex, Malaria, Metabolism, MHC class I, MHC class II, Microorganism, Molecular geometry, Molecule, Mutation, Neoplasm, Neutralizing antibody, Nucleic acid, Original antigenic sin, Oxford English Dictionary, Pathogen, Paul Ehrlich, Peptide, Phagocytosis, Plasmodium, Polyclonal B cell response, Polysaccharide, Priming (immunology), Proteasome, Protein, Protein A, Protein G, Protein L, Side-chain theory, Somatic hypermutation, Superantigen, T cell, T helper cell, T-cell receptor, Thymus, Toxin, Tumor antigen, Tumor-infiltrating lymphocytes, Vaccine, Virus, Xenobiotic, Zymogen. Expand index (45 more) »

Adaptive immune system

The adaptive immune system, also known as the acquired immune system or, more rarely, as the specific immune system, is a subsystem of the overall immune system that is composed of highly specialized, systemic cells and processes that eliminate pathogens or prevent their growth.

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An adduct (from the Latin adductus, "drawn toward" alternatively, a contraction of "addition product") is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all components.

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An adjuvant is a pharmacological or immunological agent that modifies the effect of other agents.

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An allele is a variant form of a given gene.

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An allergen is a type of antigen that produces an abnormally vigorous immune response in which the immune system fights off a perceived threat that would otherwise be harmless to the body.

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Allergies, also known as allergic diseases, are a number of conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment.

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Allotype (immunology)

In immunology, an immunoglobulin allotype is the allele of the antibody chains found in the individual.

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An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein produced mainly by plasma cells that is used by the immune system to neutralize pathogens such as pathogenic bacteria and viruses.

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In immunology, an antigen is a molecule capable of inducing an immune response (to produce an antibody) in the host organism.

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Antigen-presenting cell

An antigen-presenting cell (APC) or accessory cell is a cell that displays antigen complexed with major histocompatibility complexes (MHCs) on their surfaces; this process is known as antigen presentation.

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Antigenic escape

Antigenic escape occurs when the immune system is unable to respond to an infectious agent.

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An antitoxin is an antibody with the ability to neutralize a specific toxin.

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Apoptosis (from Ancient Greek ἀπόπτωσις "falling off") is a process of programmed cell death that occurs in multicellular organisms.

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Autoimmune disease

An autoimmune disease is a condition arising from an abnormal immune response to a normal body part.

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Autoimmunity is the system of immune responses of an organism against its own healthy cells and tissues.

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Autotransplantation is the transplantation of organs, tissues, or even particular proteins from one part of the body to another in the same person (auto- meaning "self" in Greek).

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B cell

B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype.

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B-cell receptor

The B-cell receptor or BCR is composed of immunoglobulin molecules that form a type 1 transmembrane receptor protein usually located on the outer surface of a lymphocyte type known as B cells.

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Bacteria (common noun bacteria, singular bacterium) is a type of biological cell.

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In molecular biology, CD4 (cluster of differentiation 4) is a glycoprotein found on the surface of immune cells such as T helper cells, monocytes, macrophages, and dendritic cells.

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Central tolerance

Central tolerance, also known as negative selection, is the process of eliminating any developing T or B lymphocytes that are reactive to self.

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Cervical cancer

Cervical cancer is a cancer arising from the cervix.

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Complementarity-determining region

Complementarity-determining regions (CDRs) are part of the variable chains in immunoglobulins (antibodies) and T cell receptors, generated by B-cells and T-cells respectively, where these molecules bind to their specific antigen.

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Conformational epitope

A conformational epitope is a sequence of sub-units (usually amino acids) composing an antigen that come in direct contact with a receptor of the immune system.

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Cross-reactivity, in a general sense, applies to the reaction between two different species as opposed to self-reactivity.

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Cytokines are a broad and loose category of small proteins (~5–20 kDa) that are important in cell signaling.

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Cytotoxic T cell

A cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell, cytolytic T cell, CD8+ T-cell or killer T cell) is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.

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Endocytosis is a form of bulk transport in which a cell transports molecules (such as proteins) into the cell (endo- + cytosis) by engulfing them in an energy-using process.

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Endoplasmic reticulum

The endoplasmic reticulum (ER) is a type of organelle found in eukaryotic cells that forms an interconnected network of flattened, membrane-enclosed sacs or tube-like structures known as cisternae.

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An epitope, also known as antigenic determinant, is the part of an antigen that is recognized by the immune system, specifically by antibodies, B cells, or T cells.

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The exome is the part of the genome composed of exons, the sequences which, when transcribed, remain within the mature RNA after introns are removed by RNA splicing and contribute to the final protein product encoded by that gene.

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Fragment antigen-binding

The antigen-binding (Fab) fragment is a region on an antibody that binds to antigens.

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In the fields of molecular biology and genetics, a genome is the genetic material of an organism.

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Haptens are minute molecules that elicit an immune response only when attached to a large carrier such as a protein; the carrier may be one that also does not elicit an immune response by itself.

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Head and neck cancer

Head and neck cancer is a group of cancers that starts in the mouth, nose, throat, larynx, sinuses, or salivary glands.

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Homeostasis is the tendency of organisms to auto-regulate and maintain their internal environment in a stable state.

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Host (biology)

In biology and medicine, a host is an organism that harbours a parasitic, a mutualistic, or a commensalist guest (symbiont), the guest typically being provided with nourishment and shelter.

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An idiotope is the unique set of antigenic determinants (epitopes) of the variable portion of an antibody.

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In immunology, an idiotype is a shared characteristic between a group of immunoglobulin or T cell receptor (TCR) molecules based upon the antigen binding specificity and therefore structure of their variable region.

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Immune response

The Immune response is the body's response caused by its immune system being activated by antigens.

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Immune system

The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease.

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An immunogen is an antigen or any substance that may be specifically bound by components of the immune system (antibody, lymphocytes).

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Immunogenicity is the ability of a particular substance, such as an antigen or epitope, to provoke an immune response in the body of a human and other animal.

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Immunology is a branch of biology that covers the study of immune systems in all organisms.

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Infection is the invasion of an organism's body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to the infectious agents and the toxins they produce.

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Ingestion is the consumption of a substance by an organism.

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Inhalation (also known as inspiration) happens when oxygen from the air enters the lungs.

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Injection (medicine)

Injection (often referred to as a "shot" in US English, or a "jab" in UK English) is the act of putting a liquid, especially a drug, into a person's body using a needle (usually a hypodermic needle) and a syringe.

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László Detre (microbiologist)

László Detre (October 29, 1874, Nagysurány – May 7, 1939, Washington, DC (a.k.a. Ladislas Deutsch, Ladislaus Deutsch"Origins of the Terms 'Antibody' and 'Antigen'", Scand. J. Immunol., 19, 281-285, 1984) was a Hungarian physician and microbiologist, the founder and first director of the Hungarian Serum Institute in Budapest. Detre coined the term "antigen" in a 1903 French-language paper co-authored with Russian biologist Élie Metchnikoff (referring to "substances immunogènes ou antigènes"), although the word and concept appears in his research as early as 1899. He is also a codiscoverer of the Wassermann reaction, publishing his discovery in humans just two weeks after Wassermann documented his findings in apes.

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Linear epitope

A linear or a sequential epitope is an epitope that is recognized by antibodies by its linear sequence of amino acids, or primary structure.

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In biology and biochemistry, a lipid is a biomolecule that is soluble in nonpolar solvents.

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Lysis (Greek λύσις lýsis, "a loosing" from λύειν lýein, "to unbind") refers to the breaking down of the membrane of a cell, often by viral, enzymic, or osmotic (that is, "lytic") mechanisms that compromise its integrity.

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Macrophages (big eaters, from Greek μακρός (makrós).

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Magnetic immunoassay

Magnetic immunoassay (MIA) is a novel type of diagnostic immunoassay using magnetic beads as labels in lieu of conventional enzymes (ELISA), radioisotopes (RIA) or fluorescent moieties (fluorescent immunoassays).

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Major histocompatibility complex

The major histocompatibility complex (MHC) is a set of cell surface proteins essential for the acquired immune system to recognize foreign molecules in vertebrates, which in turn determines histocompatibility.

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Malaria is a mosquito-borne infectious disease affecting humans and other animals caused by parasitic protozoans (a group of single-celled microorganisms) belonging to the Plasmodium type.

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Metabolism (from μεταβολή metabolē, "change") is the set of life-sustaining chemical transformations within the cells of organisms.

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MHC class I

MHC class I molecules are one of two primary classes of major histocompatibility complex (MHC) molecules (the other being MHC class II) and are found on the cell surface of all nucleated cells in the bodies of jawed vertebrates.

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MHC class II

MHC class II molecules are a class of major histocompatibility complex (MHC) molecules normally found only on antigen-presenting cells such as dendritic cells, mononuclear phagocytes, some endothelial cells, thymic epithelial cells, and B cells.

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A microorganism, or microbe, is a microscopic organism, which may exist in its single-celled form or in a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from 6th century BC India and the 1st century BC book On Agriculture by Marcus Terentius Varro. Microbiology, the scientific study of microorganisms, began with their observation under the microscope in the 1670s by Antonie van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera and anthrax. Microorganisms include all unicellular organisms and so are extremely diverse. Of the three domains of life identified by Carl Woese, all of the Archaea and Bacteria are microorganisms. These were previously grouped together in the two domain system as Prokaryotes, the other being the eukaryotes. The third domain Eukaryota includes all multicellular organisms and many unicellular protists and protozoans. Some protists are related to animals and some to green plants. Many of the multicellular organisms are microscopic, namely micro-animals, some fungi and some algae, but these are not discussed here. They live in almost every habitat from the poles to the equator, deserts, geysers, rocks and the deep sea. Some are adapted to extremes such as very hot or very cold conditions, others to high pressure and a few such as Deinococcus radiodurans to high radiation environments. Microorganisms also make up the microbiota found in and on all multicellular organisms. A December 2017 report stated that 3.45 billion year old Australian rocks once contained microorganisms, the earliest direct evidence of life on Earth. Microbes are important in human culture and health in many ways, serving to ferment foods, treat sewage, produce fuel, enzymes and other bioactive compounds. They are essential tools in biology as model organisms and have been put to use in biological warfare and bioterrorism. They are a vital component of fertile soils. In the human body microorganisms make up the human microbiota including the essential gut flora. They are the pathogens responsible for many infectious diseases and as such are the target of hygiene measures.

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Molecular geometry

Molecular geometry is the three-dimensional arrangement of the atoms that constitute a molecule.

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A molecule is an electrically neutral group of two or more atoms held together by chemical bonds.

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In biology, a mutation is the permanent alteration of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA or other genetic elements.

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Neoplasia is a type of abnormal and excessive growth of tissue.

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Neutralizing antibody

A neutralizing antibody (NAb) is an antibody that defends a cell from an antigen or infectious body by neutralizing any effect it has biologically.

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Nucleic acid

Nucleic acids are biopolymers, or small biomolecules, essential to all known forms of life.

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Original antigenic sin

Original antigenic sin, also known as the Hoskins effect, refers to the propensity of the body's immune system to preferentially utilize immunological memory based on a previous infection when a second slightly different version of that foreign entity (e.g. a virus or bacterium) is encountered.

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Oxford English Dictionary

The Oxford English Dictionary (OED) is the main historical dictionary of the English language, published by the Oxford University Press.

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In biology, a pathogen (πάθος pathos "suffering, passion" and -γενής -genēs "producer of") or a '''germ''' in the oldest and broadest sense is anything that can produce disease; the term came into use in the 1880s.

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Paul Ehrlich

Paul Ehrlich (14 March 1854 – 20 August 1915) was a German Jewish physician and scientist who worked in the fields of hematology, immunology, and antimicrobial chemotherapy.

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Peptides (from Gr.: πεπτός, peptós "digested"; derived from πέσσειν, péssein "to digest") are short chains of amino acid monomers linked by peptide (amide) bonds.

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In cell biology, phagocytosis is the process by which a cell—often a phagocyte or a protist—engulfs a solid particle to form an internal compartment known as a phagosome.

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Plasmodium is a genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects.

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Polyclonal B cell response

Polyclonal B cell response is a natural mode of immune response exhibited by the adaptive immune system of mammals.

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Polysaccharides are polymeric carbohydrate molecules composed of long chains of monosaccharide units bound together by glycosidic linkages, and on hydrolysis give the constituent monosaccharides or oligosaccharides.

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Priming (immunology)

The first contact of a T or B cell with its specific antigen is called priming and causes differentiation into effector T or B cells (cytotoxic, cytokine, antibody).

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Proteasomes are protein complexes which degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks peptide bonds.

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Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues.

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Protein A

Protein A is a 42 kDa surface protein originally found in the cell wall of the bacteria Staphylococcus aureus.

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Protein G

Protein G is an immunoglobulin-binding protein expressed in group C and G Streptococcal bacteria much like Protein A but with differing binding specificities.

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Protein L

Protein L was first isolated from the surface of bacterial species Peptostreptococcus magnus and was found to bind immunoglobulins through L chain interaction, from which the name was suggested.

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Side-chain theory

The side-chain theory (German, Seitenkettentheorie) is a theory proposed by Paul Ehrlich (1854–1915) to explain the immune response in living cells.

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Somatic hypermutation

Somatic hypermutation (or SHM) is a cellular mechanism by which the immune system adapts to the new foreign elements that confront it (e.g. microbes), as seen during class switching.

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Superantigens (SAgs) are a class of antigens that cause non-specific activation of T-cells resulting in polyclonal T cell activation and massive cytokine release.

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T cell

A T cell, or T lymphocyte, is a type of lymphocyte (a subtype of white blood cell) that plays a central role in cell-mediated immunity.

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T helper cell

The T helper cells (Th cells) are a type of T cell that play an important role in the immune system, particularly in the adaptive immune system.

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T-cell receptor

The T-cell receptor, or TCR, is a molecule found on the surface of T cells, or T lymphocytes, that is responsible for recognizing fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules.

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The thymus is a specialized primary lymphoid organ of the immune system.

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A toxin (from toxikon) is a poisonous substance produced within living cells or organisms; synthetic toxicants created by artificial processes are thus excluded.

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Tumor antigen

Tumor antigen is an antigenic substance produced in tumor cells, i.e., it triggers an immune response in the host.

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Tumor-infiltrating lymphocytes

Tumor-infiltrating lymphocytes are white blood cells that have left the bloodstream and migrated toward tumor.

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A vaccine is a biological preparation that provides active acquired immunity to a particular disease.

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A virus is a small infectious agent that replicates only inside the living cells of other organisms.

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A xenobiotic is a chemical substance found within an organism that is not naturally produced or expected to be present within the organism.

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A zymogen, also called a proenzyme, is an inactive precursor of an enzyme.

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[1] https://en.wikipedia.org/wiki/Antigen

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