• The heat-stable component was responsible for immunity against specific microorganisms, whereas the heat-sensitive component was responsible for the non-specific antimicrobial activity conferred by all normal sera. (wikipedia.org)
  • The heat-stable component was found to confer immunity against specific microorganisms, while the heat-labile component was found to be responsible for the non-specific antimicrobial activity conferred by all normal serum. (wikidoc.org)
  • The classical complement pathway typically requires antigen-antibody complexes for activation (specific immune response), whereas the alternative pathway can be activated by spontaneous complement component 3 (C3) hydrolysis, foreign material, pathogens, or damaged cells. (wikipedia.org)
  • The classical complement pathway typically requires antibodies for activation (specific immune response), while the alternative and mannose-binding lectin pathways can be activated by C3 hydrolysis or antigens without the presence of antibodies (non-specific immune response). (wikidoc.org)
  • About 50 proteins and protein fragments make up the complement system, including serum proteins, and cell membrane receptors. (wikipedia.org)
  • Heating the serum destroyed its killing activity. (wikipedia.org)
  • Nevertheless, the heat-inactivated serum, when injected into guinea pigs exposed to the cholera bacteria, maintained its ability to protect the animals from illness. (wikipedia.org)
  • Those receptors, which we now call "antibodies", were called by Ehrlich "amboceptors" to emphasise their bifunctional binding capacity: They recognise and bind to a specific antigen, but they also recognise and bind to the heat-labile antimicrobial component of fresh serum. (wikipedia.org)
  • In the late 19th century, serum was found to contain a nonspecific heat-labile complementary principle that interacted with antibodies to induce bacteriolysis. (medscape.com)
  • The complement system as understood today is a multimolecular system composed of more than 32 proteins and consisting of serum proteins, serosal proteins, and cell membrane receptors that bind to complement fragments. (medscape.com)
  • The complement system consists of 7 serum and 9 membrane regulatory proteins, 1 serosal regulatory protein, and 8 cell membrane receptors that bind complement fragments. (medscape.com)
  • Heat-labile meaning that it lost its effectiveness if the serum was heated. (wikidoc.org)
  • The second phase for each involves cleavage of C3b, generating multiple biologically important fragments and large, potentially cytolytic complexes. (medscape.com)
  • Three biochemical pathways activate the complement system: the classical complement pathway, the alternative complement pathway, and the lectin pathway. (wikipedia.org)
  • Activation of the complement pathways. (medscape.com)
  • In all three pathways, a C3-convertase cleaves and activates component C3 , creating C3a and C3b and causing a cascade of further cleavage and activation events. (wikidoc.org)
  • The classical and alternative complement pathways. (wikidoc.org)
  • The complement system is an integral part of the innate immune system but also augments adaptive immune responses. (wjgnet.com)
  • Ehrlich introduced the term "complement" as part of his larger theory of the immune system. (wikipedia.org)
  • Ehrlich, therefore, named this heat-labile component "complement", because it is something in the blood that "complements" the cells of the immune system. (wikipedia.org)
  • Ehrlich believed that each antigen-specific amboceptor has its own specific complement, whereas Bordet believed that there is only one type of complement. (wikipedia.org)
  • Ehrlich and Morgan termed this factor complement. (medscape.com)
  • The term "complement" was introduced by Paul Ehrlich in the late 1890s, as part of his larger theory of the immune system. (wikidoc.org)
  • The complement system, also known as complement cascade, is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and attack the pathogen's cell membrane. (wikipedia.org)
  • The complement system can, however, be recruited and brought into action by antibodies generated by the adaptive immune system. (wikipedia.org)
  • According to this theory, the immune system consists of cells that have specific receptors on their surface to recognize antigens. (wikipedia.org)
  • citation needed] Complement triggers the following immune functions: Membrane attack - by rupturing the cell wall of bacteria. (wikipedia.org)
  • The complement system consists of a number of small proteins that are synthesized by the liver, and circulate in the blood as inactive precursors. (wikipedia.org)
  • Lectin pathway) Most of the proteins and glycoproteins that constitute the complement system are synthesized by hepatocytes. (wikipedia.org)
  • The complement system consists of a number of small proteins found in the blood, normally circulating as inactive zymogens . (wikidoc.org)
  • The complement system is a biochemical cascade which helps clear pathogens from an organism. (wikidoc.org)
  • Kupffer cells and other macrophage cell types help clear complement-coated pathogens. (wikidoc.org)
  • Jules Bordet, a young Belgian scientist in Paris at the Pasteur Institute, concluded that this principle has two components, one that maintained a "sensitizing" effect after being heated and one (alexin) whose toxic effect was lost after being heated. (wikipedia.org)
  • In 1896, Jules Bordet , a young Belgian scientist in Paris at the Pasteur Institute, demonstrated that this principle could be analyzed into two components: a heat-stable and a heat-labile component. (wikidoc.org)
  • The end result of this complement activation or complement fixation cascade is stimulation of phagocytes to clear foreign and damaged material, inflammation to attract additional phagocytes, and activation of the cell-killing membrane attack complex. (wikipedia.org)
  • Alternative Complement Pathway) Inflammation - by attracting macrophages and neutrophils. (wikipedia.org)
  • In this review we discuss current evidence that complement activation contributes to progression of CKD, how complement could cause renal inflammation and whether complement inhibition would slow progression of renal disease. (wjgnet.com)
  • Complement activation occurs in progressive chronic kidney disease and may contribute to the chronic inflammation that is characteristically found in the kidney. (wjgnet.com)
  • It is therefore possible that inhibiting complement activation would reduce inflammation, lead to reduced fibrosis and preservation of renal function. (wjgnet.com)
  • Depending on the nature of complement activators, the classic pathway, the alternative pathway, or the more recently discovered lectin pathway is activated predominantly to produce C3 convertase. (medscape.com)
  • In the early 20th century, this controversy was resolved when it became understood that complement can act in combination with specific antibodies, or on its own in a non-specific way. (wikipedia.org)
  • The complement system functions as an interactive sequence, with one reaction leading to another in the form of a cascade. (medscape.com)
  • The end result of this activation cascade is massive amplification of the response and activation of the cell-killing membrane attack complex . (wikidoc.org)
  • C5b initiates the membrane attack pathway , which results in the membrane attack complex (MAC), consisting of C5b, C6 , C7 , C8 , and polymeric C9 . (wikidoc.org)
  • One, the recognition unit, consists of a trimolecular complex of C1q, 2 molecules of C1r, and 2 molecules of C1s held together by calcium. (medscape.com)
  • The classical pathway is triggered by activation of the C1-complex (which consists of one molecule C1q and two molecules C1r and C1s), either by C1q's binding to antibodies from classes M and G, complexed with antigens , or by its binding C1q to the surface of the pathogen. (wikidoc.org)
  • Binding of factor H to C3b increases its inactivation by factor I. Properdin stabilizes it, preventing its inactivation by factors H and I. The alternate pathway does not result in a truly nonspecific activation of complement because it requires specific types of compounds for activation. (medscape.com)
  • Complement activation is known to occur in many diverse renal diseases, including glomerulonephritis, thrombotic microangiopathies and transplant rejection. (wjgnet.com)
  • In the first phase, a series of specific interactions leads to formation of intrinsic complement proteinase, termed C3 convertase. (medscape.com)
  • It simply does not require specific antigen-antibody interactions for initiation. (medscape.com)
  • C1q can also be activated by mycoplasmal organisms, RNA viruses, bacterial endotoxins, and cell membranes of some organelles without the presence of antibody. (medscape.com)
  • The complement system can, however, be recruited and brought into action by antibodies generated by the adaptive immune system. (wikipedia.org)
  • Alternative Complement Pathway) Inflammation - by attracting macrophages and neutrophils. (wikipedia.org)
  • citation needed] Complement triggers the following immune functions: Membrane attack - by rupturing the cell wall of bacteria. (wikipedia.org)