complement system

(noun)

an aspect of the innate immune system that supplements the actions of the antibodies and phagocytic cells in clearing out pathogens from an organism

Related Terms

Examples of complement system in the following topics:

  • The Complement System

    • Around 20 soluble proteins comprise the complement system, which helps destroy extracellular microorganisms that have invaded the body.
    • Using a combination of cellular and molecular attacks, the innate immune system identifies the nature of a pathogen and responds with inflammation, phagocytosis (where a cell engulfs a foreign particle), cytokine release, destruction by NK cells, and/or a complement system.
    • In this concept, we will discuss the complement system.
    • An array of approximately 20 types of soluble proteins, called a complement system, functions to destroy extracellular pathogens.
    • The complement system is so named because it is complementary to the antibody response of the adaptive immune system.

  • Humoral Immune Response

    • B cells containing antibodies that recognize "self" antigens are destroyed before they can mature, preventing the immune system from attacking the host.
    • These antibodies circulate in the blood stream and lymphatic system, binding with the antigen whenever it is encountered.
    • The antigen-antibody complex stimulates the complement system described previously, destroying the cell bearing the antigen.
    • This describes the host's active response of the immune system to an infection or to a vaccination.
    • Antibodies may inhibit infection by (a) preventing the antigen from binding its target, (b) tagging a pathogen for destruction by macrophages or neutrophils, or (c) activating the complement cascade.

  • Hypersensitivities

    • In systemic lupus erythematosus, a diffuse autoantibody response to the individual's own DNA and proteins results in various systemic diseases.
    • Systemic lupus erythematosus may affect the heart, joints, lungs, skin, kidneys, central nervous system, or other tissues, causing tissue damage via antibody binding, complement recruitment, lysis, and inflammation .
    • Systemic lupus erythematosus is characterized by autoimmunity to the individual's own DNA and/or proteins, which leads to varied dysfunction of the organs.
    • Distinguish between the disruptions to the immune system caused by allergies and autoimmunity

  • Antibody Functions

    • In another process, complement fixation, IgM and IgG in serum bind to antigens, providing docking sites onto which sequential complement proteins can bind.
    • The combination of antibodies and complement enhances opsonization even further, promoting rapid clearing of pathogens.
    • Patients who develop systemic lupus erythematosus (SLE) commonly exhibit antibodies that react with their own DNA.
    • Antibodies may inhibit infection by (a) preventing the antigen from binding to its target, (b) tagging a pathogen for destruction by macrophages or neutrophils, or (c) activating the complement cascade.

  • Genomics and Proteomics

    • Put more simply, proteomics analyzes the structure and function of biological systems.
    • Proteomics complements genomics and is useful when scientists want to test their hypotheses that were based on genes.

  • Mechanics of Cellular Differentation

    • Similarly, all cells contain the same full complement of DNA, but each type of cell only "reads" the portions of DNA that are relevant to its own functioning.
    • The multipotent hematopoietic stem cells give rise to many different cell types, including the cells of the immune system and red blood cells.

  • Genomic DNA and Chromosomes

    • The genome of an organism consists of its entire complement of DNA, which encodes the genes that control the organism's characteristics.

  • Chromosomal Theory of Inheritance

    • Each parent synthesizes gametes that contain only half of their chromosomal complement.

  • Plant Tissues and Organ Systems

  • Open and Closed Circulatory Systems

    • In a closed circulatory system, blood is contained inside blood vessels, circulating unidirectionally (in one direction) from the heart around the systemic circulatory route, then returning to the heart again.
    • In contrast to a closed system, arthropods (including insects, crustaceans, and most mollusks) have an open circulatory system.
    • An open circulatory system does not use as much energy to operate and maintain as a closed system; however, there is a trade-off with the amount of blood that can be moved to metabolically-active organs and tissues that require high levels of oxygen.
    • Most vertebrates and some invertebrates, such as this annelid earthworm, have a closed circulatory system.
    • Arthropods, such as this bee and most mollusks, have open circulatory systems.