BIO - TERMS - IMMUNE Flashcards
12/23 rule
Phenomenon wherein two gene segments of an immunoglobulin or T-cell receptor can be joined only if one recognition signal sequence has a 12-base-pair spacer and the other has a 23-basepair spacer.
accelerated rejection
The more rapid rejection of a second graft after rejection of the first graft. It was one of the pieces of evidence that showed that graft rejection was due to an adaptive immune response.
acquired immune deficiency syndrome (AIDS)
A disease caused by infection with the human immunodeficiency virus (HIV-1). AIDS occurs when an infected patient has lost most of his or her CD4 T cells, so that infections with opportunistic pathogens occur.
acquired immunodeficiency (secondary immunodeficiency)
The inability, obtained during the life of an individual, to produce specific antibodies or T cells, due to drugs or disease.
active immunity
(i-myū′ni-tē) Activation of the immune system by a vaccine or by exposure to the naturally occurring infectious agent. Offers long-term protection because memory cells are formed. Compare to passive immunity.
Active immunization
Th e process of inducing an immune response by exposure to a vaccine; contrasts with passive immunization. (Chapter 8)
acute desensitization
An immunotherapeutic technique for rapidly inducing temporary tolerance to, for example, an essential drug such as insulin or penicillin in a person who is allergic to it. Also called rapid desensitization. When performed properly, can produce symptoms of mild to moderate anaphylaxis.
Acute infection
A common pattern of infection in which virus particles are produced rapidly, and the infection is resolved quickly by the immune system; survivors are usually immune to subsequent infection. (Chapter 5)
acute rejection
The rejection of a tissue or organ graft from a genetically unrelated donor that occurs within 10–13 days of transplantation unless prevented by immunosuppressant treatment.
adaptive immune system
System of lymphocytes providing highly specific and long-lasting defense against pathogens in vertebrates. It consists of two major classes of lymphocytes: B lymphocytes (B cells), which secrete antibodies that bind specifically to the pathogen or its products, and T lymphocytes (T cells), which can either directly kill cells infected with the pathogen or produce secreted or cell-surface signal proteins that stimulate other host cells to help eliminate the pathogen.
Adoptive transfer
Th e transfer of cells, usually lymphocytes, from an immunized donor to a nonimmune recipient. (Chapters 4 and 8)
agnathans
A class of vertebrate comprising jawless fish lacking adaptive immunity based on the RAG-mediated V(D)J recombination, but possessing a distinct system of adaptive immunity based on somatically assembled VLRs.
AIDS (acquired immunodefi ciency syndrome)
The usually fatal human disease in which the immune system is destroyed by the human immunodefi ciency virus (HIV).
airway hyperreactivity, hyperresponsiveness
The condition in which the airways are pathologically sensitive to both immunological (allergens) and nonimmunological stimuli, such as cold air, smoke, or perfumes. This hyperreactivity usually is present in chronic asthma.
allergen desensitization
An immunotherapeutic technique that aims either to change an allergic immune response to a symptom-free non-allergic response, or to develop immunologic tolerance to an allergen that has been causing unpleasant clinical symptoms. The procedure involves exposing an allergic individual to increasing doses of allergen.
allergic contact dermatitis
A largely T-cell-mediated immunological hypersensitivity reaction manifested by a skin rash at the site of contact with the allergen. Often the stimulus is a chemical agent, for example urushiol oil from the leaves of the poison ivy plant, which can haptenate normal host molecules to render them allergenic.
allograft rejection
The immunologically mediated rejection of grafted tissues or organs from a genetically nonidentical donor. It is due chiefly to recognition of nonself MHC molecules on the graft.
anti-lymphocyte globulin
Antiserum raised in another species against human T cells. It is used in the temporary suppression of immune responses in transplantation.
Artemis
An endonuclease involved in the gene rearrangements that generate functional immunoglobulin and T-cell receptor genes.
artificially acquired active immunity
The production of antibodies by the body in response to a vaccination.
artificially acquired passive immunity
The transfer of humoral antibodies formed by one individual to a susceptible individual, accomplished by the injection of antiserum.
aryl hydrocarbon receptor (AhR)
A basic helix-loop-helix transcription factor that is activated by various aromatic ligands including, famously, dioxin. It functions in the normal activity of several types of immune cells including some ILCs and IELs.
autoimmune lymphoproliferative syndrome (ALPS)
An inherited syndrome in which a defect in the Fas gene leads to a failure in normal apoptosis, causing unregulated immune responses, including autoimmune responses.
azathioprine
A powerful cytotoxic drug that is converted to its active form in vivo, which then kills rapidly proliferating cells, including proliferating lymphocytes; it is used as an immunosuppressant to treat autoimmune disease and in transplantation.
BCG vaccine
A live, attenuated strain of Mycobacterium bovis used to provide immunity to tuberculosis.
Bence Jones protein
Immunoglobulin light chains overproduced by some patients with multiple myeloma (a malignant plasma cell dyscrasia).
bone marrow
The tissue where all the cellular elements of the blood—red blood cells, white blood cells, and platelets—are initially generated from hematopoietic stem cells. The bone marrow is also the site of further B-cell development in mammals and the source of stem cells that give rise to T cells on migration to the thymus. Thus, bone marrow transplantation can restore all the cellular elements of the blood, including the cells required for adaptive immune responses.
Bruton’s tyrosine kinase (Btk)
A Tec-family tyrosine kinase important in B-cell receptor signaling. Btk is mutated in the human immunodeficiency disease X-linked agammaglobulinemia.
Burkitt lymphoma
A B-cell malignancy in which the myc proto-oncogene has been translocated to an immunoglobulin locus.
C-type lectins
Large class of carbohydrate-binding proteins that require Ca2+ for binding, including many that function in innate immunity.
calcineurin
A cytosolic serine/threonine phosphatase with a crucial role in signaling via the T-cell receptor. The immunosuppressive drugs cyclosporin A and tacrolimus inactivate calcineurin, suppressing T-cell responses.
cancer immunoediting
A process that occurs during the development of a cancer when it is acquiring mutations that favor its survival and escape from immune responses, such that cancer cells with these mutations are selected for survival and growth.
cellular immunology
The study of the cellular basis of immunity. central lymphoid organs, central lymphoid tissues The sites of lymphocyte development; in humans, these are the bone marrow and thymus. B lymphocytes develop in bone marrow, whereas T lymphocytes develop within the thymus from bone marrow-derived progenitors. Also called the primary lymphoid organs.
chronic granulomatous disease (CGD)
An immunodeficiency in which multiple granulomas form as a result of defective elimination of bacteria by phagocytic cells. It is caused by defects in the NADPH oxidase system of enzymes that generate the superoxide radical involved in bacterial killing.
chronic rejection
Late failure of a transplanted organ, which can be due to immunological or nonimmunological causes.
common mucosal immune system
The mucosal immune system as a whole, the name reflecting the fact that lymphocytes that have been primed in one part of the mucosal system can recirculate as effector cells to other parts of the mucosal system.
common myeloid progenitor (CMP)
Stem cells that can give rise to the myeloid cells of the immune system—macrophages, granulocytes, mast cells, and dendritic cells of the innate immune system. This stem cell also gives rise to megakaryocytes and red blood cells.
congenital immunodeficiency (primary immunodeficiency)
The inability, due to an individual’s genotype, to produce specific antibodies or T cells.
constant Ig domains (C domains)
Type of protein domain that makes up the constant regions of each chain of an immunoglobulin molecule.
CRIg (complement receptor of the immunoglobulin family)
A complement receptor that binds to inactivated forms of C3b.
cyclosporin A (CsA)
A powerful noncytotoxic immunosuppressive drug that inhibits signaling from the T-cell receptor, preventing T-cell activation and effector function. It binds to cyclophilin, and the complex formed binds to and inactivates the phosphatase calcineurin.
depleting antibodies
Immunosuppressive monoclonal antibodies that trigger the destruction of lymphocytes in vivo. They are used for treating episodes of acute graft rejection.
DiGeorge syndrome
Recessive genetic immunodeficiency disease in which there is a failure to develop thymic epithelium. Parathyroid glands are also absent and there are anomalies in the large blood vessels.
Dscam
A member of the immunoglobulin superfamily that in insects is thought to opsonize invading bacteria and aid their engulfment by phagocytes. It can be made in a multiplicity of different forms as a result of alternative splicing.
DTaP vaccine
A combined vaccine used to provide active immunity, containing diphtheria and tetanus toxoids and Bordetella pertussis cell fragments.
dysregulated self
Refers to changes that take place in infected or malignant cells that alter expression of various surface receptors that can be detected by the innate immune system.
effector cell
Cell that carries out the final response or function in a particular process. The main effector cells of the immune system, for example, are activated lymphocytes and phagocytes that help eliminate pathogens.
effector mechanisms
Those processes by which pathogens are destroyed and cleared from the body. Innate and adaptive immune responses use most of the same effector mechanisms to eliminate pathogens.
effector modules
This term refers to a set of immune mechanisms, either cell-mediated and humoral, innate or adaptive, that act together in the elimination of a particular category of pathogen.
effector T lymphocytes
The T cells that perform the functions of an immune response, such as cell killing and cell activation, that clear the infectious agent from the body. There are several different subsets, each with a specific role in an immune response.
elimination phase
Stage of anti-tumor immune response that detects and eliminates cancer cells, also called immune surveillance.
fibrinogen-related proteins (FREPs)
Members of the immunoglobulin superfamily that are thought to have a role in innate immunity in the freshwater snail Biomphalaria glabrata.
fingolimod
Small-molecule immunosuppressive drug that interferes with the actions of sphingosine, leading to retention of effector T cells in lymphoid organs.
FK-binding proteins (FKBPs)
Group of prolyl isomerases related to the cyclophilins and bind the immunosuppressive drug FK506 (tacrolimus).
framework regions
Relatively invariant regions that provide a protein scaffold for the hypervariable regions in the V domains of immunoglobulins and T-cell receptors.
gene rearrangement
The process of somatic recombination of gene segments in the immunoglobulin and T-cell receptor genetic loci to produce a functional gene. This process generates the diversity found in immunoglobulin and T-cell receptor variable regions.
Genetic drift
Diversity in viral genomes that arises as a result of errors during genome replication and immune selection. (Chapter 10)
genetic locus
The site of a gene on a chromosome. In the case of the genes for the immunoglobulin and T-cell receptor chains, the term locus refers to the complete collection of gene segments and C-region genes for the given chain.
germinal center
Sites of intense B-cell proliferation and differentiation that develop in lymphoid follicles during an adaptive immune response. Somatic hypermutation and class switching occur in germinal centers.
Globulins
Common proteins in the blood that are insoluble in water and soluble in salt solutions. Alpha, beta, and gamma globulins can be distinguished in human blood serum. Gamma globulins are important in developing immunity to diseases.
gnathostomes
The class of jawed vertebrates comprising most fish and all mammals. These possess an adaptive immunity based on the RAG-mediated V(D)J recombination.
Gram-negative binding proteins (GNBPs)
Proteins that act as the pathogen-recognition proteins in the Toll pathway of immune defense in Drosophila.
Griscelli syndrome
An inherited immunodeficiency disease that affects the pathway for secretion of lysosomes. It is caused by mutations in a small GTPase Rab27a, which controls the movement of vesicles within cells.
gut-associated lymphoid tissues (GALT)
Lymphoid tissues associated with the gastrointestinal tract, comprising Peyer’s patches, the appendix, and isolated lymphoid follicles found in the intestinal wall, where adaptive immune responses are initiated, and by lymphatics to mesenteric lymph nodes.
heavy-chain variable region (VH)
Referring to the V region of the heavy chain of an immunoglobulin.
hematopoietin superfamily
Large family of structurally related cytokines that includes growth factors and many interleukins with roles in both adaptive and innate immunity.
heterosubtypic immunity
Immune protection against a pathogen conferred by infection with a distinct strain, typically with reference to different influenza A serotypes.
hinge region
The flexible domain that joins the Fab arms to the Fc piece in an immunoglobulin. The flexibility of the hinge region in IgG and IgA molecules allows the Fab arms to adopt a wide range of angles, permitting binding to epitopes spaced variable distances apart.
