Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 6836694

Complement activation by plasma separator membranes.

B C McLeod·A Viernes·R J Sassetti
View original source ↗Export metadata ↓

Abstract

Because of their structural similarity to dialysis membranes, six plasma separator membranes were evaluated for the ability to activate complement, as judged by immunoconversion of the third component of complement in crossed immunoelectrophoresis. A polysulfone and two cellulose acetate membranes were relatively strong alternative pathway activators. Polypropylene, poly[vinylidine fluoride] and polyvinyl-chloride derivative membranes were weak activators in some sera. Membrane activation was inhibited in citrate-anticoagulated but not in heparin-anticoagulated plasma. The results of such in vitro screening should be of value in selecting materials and anticoagulation regimens for membrane plasma separators.

Explore related subjects

Complement ActivationComplement C3HumansMembranes, ArtificialPlasmapheresisJournal ArticleResearch Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

B C McLeod, A Viernes, R J Sassetti. Complement activation by plasma separator membranes.. https://doi.org/10.1046/j.1537-2995.1983.23283172853.x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1997

[Susceptibility to infection].

Recurrent infections in individual patients prompt concern regarding an underlying immunodeficiency. It is often difficult to make a distinction between "normal" and abnormally frequent occurrence of infections. Infectious diseases are the result of a series of complicated interactions between host factors, pathogen properties and epidemiological circumstances. This paper reviews the role of non-specific and antigen-specific host factors relevant to the management of a patient with suspected immunodeficiency. The most important effector mechanisms of immune defence are outlined and the consequences of their failure with respect to specific infections are discussed. Analysis of the clinical presentation, pathophysiology and microorganisms involved offers clues as to which part of the immune system is failing in an individual patient. Based on this, further tests will confirm or exclude an underlying immunodeficiency. The paper concludes with an overview of relevant therapeutic and prophylactic options.

Complement Activation↗
PubMed1997

Elimination of N-linked glycosylation sites from the human IgA1 constant region: effects on structure and function.

IgA1 Abs possess conserved N-linked glycosylation sites in the second C region and secreted tailpiece domains. To understand the role of these carbohydrates in the structure and function of human IgA1, site-directed mutants that produce human IgA1 lacking either one or both of the N-linked carbohydrate sites have been produced. When the mutant heavy chains are expressed in myeloma lines producing the relevant kappa-light chain, efficient secretion of the monomer and dimer forms of IgA1 is seen. In addition, higher polymer forms of the IgA molecules lacking the third domain carbohydrate, either singly or in the double mutant, are present. Functional analysis of the IgA1 proteins has shown significant differences between the various mutants and wild-type IgA. The carbohydrate mutants show a reduced affinity for their target Ag, dansyl. All of the IgA1 molecules retained the ability to bind to the polymeric Ig receptor. C3 binding was observed for all of the IgA molecules, with the IgA mutants lacking the third domain carbohydrate showing a reduced ability to bind C3; however, IgA did not effectively activate the alternative pathway, as determined by factor B cleavage and terminal complex binding. These studies demonstrate that N-linked glycosylation in the constant domain of human IgA1 plays an important role in the biologic properties of IgA1.

Complement Activation↗
PubMed1997

Haemolytic complement consumption by Parietaria pollen extracts in relation to peptide-bound flavonoids.

Inhaled allergens from house dust, mites or animal danders activate human complement in vitro by engaging the C1-component through a non-antibody-dependent mechanism. These earlier findings are extended by showing that the allergenic components in extracts of Parietaria pollen are almost equally potent complement activators as those from house dust or mites. Spectroscopic evidence indicates that haemolytic complement consumption by the Parietaria allergens and their enzymic fragments is most likely related to post-translational side-chains comprising flavonoid derivatives. These adsorbed and/or peptide-bound tannin-like structures may also explain the exceptional stability of the high- and low-molecular mass allergenic components in Parietaria pollen extracts.

Complement Activation↗