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Idiotype
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. The variable region of antigen receptors of T cells (TCRs) and B cells (immunoglobulins) contain complementarity-determining regions (CDRs) with unique amino acid sequences. They define the surface and properties of the variable region, determining the antigen specificity and therefore the idiotope of the molecule. Immunoglobulins or TCRs with a shared idiotope are the same idiotype. Antibody idiotype is determined by: *Gene rearrangement *Junctional diversity *P-nucleotides (palindromic nucleotides at sites of single-strand breaks) *N-nucleotides *Somatic hypermutations Etymology and usage The word idiotype comes from two Greek roots, ''idio'' meaning 'private, distinctive, peculiar' and ''typos'' meaning 'mark.' Thus, idiotype describes the distinctive sequence and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoglobulin
An antibody (Ab) or immunoglobulin (Ig) is a large, Y-shaped protein belonging to the immunoglobulin superfamily which is used by the immune system to identify and neutralize antigens such as pathogenic bacteria, bacteria and viruses, including those that cause disease. Each individual antibody recognizes one or more specific antigens, and antigens of virtually any size and chemical composition can be recognized. Antigen literally means "antibody generator", as it is the presence of an antigen that drives the formation of an antigen-specific antibody. Each of the branching chains comprising the "Y" of an antibody contains a paratope that specifically binds to one particular epitope on an antigen, allowing the two molecules to bind together with precision. Using this mechanism, antibodies can effectively "tag" the antigen (or a microbe or an infected cell bearing such an antigen) for attack by cells of the immune system, or can neutralize it directly (for example, by blocking a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antigen
In immunology, an antigen (Ag) is a molecule, moiety, foreign particulate matter, or an allergen, such as pollen, that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune response. Antigens can be proteins, peptides (amino acid chains), polysaccharides (chains of simple sugars), lipids, or nucleic acids. Antigens exist on normal cells, cancer cells, parasites, viruses, fungus, fungi, and bacteria. Antigens are recognized by antigen receptors, including antibodies and T-cell receptors. Diverse antigen receptors are made by cells of the immune system so that each cell has a specificity for a single antigen. Upon exposure to an antigen, only the lymphocytes that recognize that antigen are activated and expanded, a process known as clonal selection. In most cases, antibodies are ''antigen-specific'', meaning that an antibody can only react to and bind one specific antigen; in some instances, however, antibodies may cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Idiotope
In immunology, an idiotope is the unique set of antigenic determinants (epitopes) of the variable portion of an antibody. In some cases it can be the actual antigen-binding site, and in some cases it may comprise variable region sequences outside of the antigen-binding site on the antibody itself. Thus each antibody would have multiple idiotopes and the set of these individual idiotopes is termed the ''idiotype'' of the antibody. Idiotopes contrast with allotopes, which are non-varying structures on the Fc receptor. If a separate antibody is produced that has specific binding capabilities to an idiotope of the previously described antibody, it is said to be an "anti-idiotypic antibody". If such is the case, the anti-idiotypic antibodies will be able to bind to the B lymphocyte receptor for the original antigen and inhibit the immune response to that antigen. This type of regulation was proposed by Danish immunologist Niels Jerne in 1974. He termed it the "Network Hypothesis". T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niels Jerne
Niels Kaj Jerne, FRS (23 December 1911 – 7 October 1994) was a Danish immunologist. He shared the Nobel Prize in Physiology or Medicine in 1984 with Georges J. F. Köhler and César Milstein "for theories concerning the specificity in development and control of the immune system and the discovery of the principle for production of monoclonal antibodies". Jerne is known for three significant ideas. Firstly, instead of the body producing antibodies in response to an antigen, Jerne postulated that the immune system already has the specific antibodies it needs to fight antigens. Secondly, it was known that the immune system learns to be tolerant to the individual's own self. Jerne postulated that this learning takes place in the thymus. Thirdly, it was known that T cells and B cells communicate with each other. Jerne's network theory proposed that the active sites of antibodies are attracted to both specific antigens ( idiotypes) and to other antibodies that bind to the same ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical University Of South Carolina
The Medical University of South Carolina (MUSC) is a public medical school in Charleston, South Carolina. It opened in 1824 as a small private college aimed at training physicians and has since established hospitals and medical facilities across the state. It is one of the oldest continually operating schools of medicine in the United States and the oldest in the Deep South. The school has expanded into a state university with a medical center and six colleges for the education of health professionals, biomedical scientists, and other health care personnel. It also operates as a center for research and has a public hospital. Colleges College of Medicine History The College of Medicine began in 1823 with the incorporation of the Medical College of South Carolina, a private institution of the Medical Society of South Carolina. Seven Charleston physicians formed the initial faculty with 30 students enrolled in 1824. The first graduation was on April 4, 1825. With the excepti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotype (immunology)
In immunology, antibodies ( immunoglobulins (Ig)) are classified into several types called isotypes or classes. The variable (V) regions near the tip of the antibody can differ from molecule to molecule in countless ways, allowing it to specifically target an antigen (or more exactly, an epitope). In contrast, the constant (C) regions only occur in a few variants, which define the antibody's class. Antibodies of different classes activate distinct effector mechanisms in response to an antigen (triggering different elements of the innate immune system). They appear at different stages of an immune response, differ in structural features, and in their location around the body. Isotype expression reflects the maturation stage of a B cell. Naive B cells express IgM and IgD isotypes with unmutated variable genes, which are produced from the same initial transcript following alternative splicing. Expression of other antibody isotypes (in humans: IgG, IgA, and IgE) occurs via a proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allotype (immunology)
The word allotype comes from two Greek roots, ''allo'' meaning 'other or differing from the norm' and ''typos'' meaning 'mark'. In immunology, allotype is an immunoglobulin variation (in addition to isotypic variation) that can be found among antibody classes and is manifested by heterogeneity of immunoglobulins present in a single vertebrate species. The structure of immunoglobulin polypeptide chain is dictated and controlled by number of genes encoded in the germ line. However, these genes, as it was discovered by serologic and chemical methods, could be highly polymorphic. This polymorphism is subsequently projected to the overall amino acid structure of antibody chains. Polymorphic epitopes can be present on immunoglobulin constant regions on both heavy and light chains, differing between individuals or ethnic groups and in some cases may pose as immunogenic determinants. Exposure of individuals to a non-self allotype might elicit an anti- allotype response and became ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immune Network Theory
The immune network theory is a theory of how the adaptive immune system works, that has been developed since 1974 mainly by Niels Jerne and Geoffrey W. Hoffmann. The theory states that the immune system is an interacting network of lymphocytes and molecules that have variable (V) regions. These V regions bind not only to things that are foreign to the vertebrate, but also to other V regions within the system. The immune system is therefore seen as a network, with the components connected to each other by V-V interactions. It has been suggested that the phenomena that the theory describes in terms of networks are also explained by clonal selection theory. The scope of the symmetrical network theory developed by Hoffmann includes the phenomena of low dose and high dose tolerance, first reported for a single antigen by Avrion Mitchison,N. A. Mitchison (1964) Induction of immunological paralysis in two zones of dosage. Proc. Royal Soc. Lond. B161, 275-292 and confirmed by Geoffrey Sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paratope
In immunology, a paratope, also known as an antigen-binding site, is the part of an antibody which recognizes and binds to an antigen. It is a small region at the tip of the antibody's antigen-binding fragment and contains parts of the antibody's heavy and light chains. Each paratope is made up of six complementarity-determining regions - three from each of the light and heavy chains - that extend from a fold of anti-parallel beta sheets. Each arm of the Y-shaped antibody has an identical paratope at the end. Paratopes make up the parts of the B-cell receptor that bind to and make contact with the epitope of an antigen. All the B-cell receptors on any one individual B cell have identical paratopes. The uniqueness of a paratope allows it to bind to only one epitope with high affinity and as a result, each B cell can only respond to one epitope. The paratopes on B-cell receptors binding to their specific epitope is a critical step in the adaptive immune response. Design of par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epitope
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. The part of an antibody that binds to the epitope is called a paratope. Although epitopes are usually non-self proteins, sequences derived from the host that can be recognized (as in the case of autoimmune diseases) are also epitopes. The epitopes of protein antigens are divided into two categories, conformational epitopes and linear epitopes, based on their structure and interaction with the paratope. Conformational and linear epitopes interact with the paratope based on the 3-D conformation adopted by the epitope, which is determined by the surface features of the involved epitope residues and the shape or tertiary structure of other segments of the antigen. A conformational epitope is formed by the 3-D conformation adopted by the interaction of discontiguous amino acid residues. In contrast, a linear epitope i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize In Physiology Or Medicine
The Nobel Prize in Physiology or Medicine () is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, according to Alfred Nobel's 1895 will, are awarded "to those who, during the preceding year, have conferred the greatest benefit to humankind". Nobel Prizes are awarded in the fields of Physics, Medicine or Physiology, Chemistry, Literature, and Peace. The Nobel Prize is presented annually on the anniversary of Alfred Nobel's death, 10 December. As of 2024, 115 Nobel Prizes in Physiology or Medicine have been awarded to 229 laureates, 216 men and 13 women. The first one was awarded in 1901 to the German physiologist, Emil von Behring, for his work on serum therapy and the development of a vaccine against diphtheria. The first woman to receive the Nobel Prize in Physiology or Medicine, Gerty Cori, received it in 1947 for her role in elucida ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
