Circulating immune complexes in the blood
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
The content of the CEC in serum is normal - 30-90 IU / ml.
Circulating immune complexes (CIC) - complexes consisting of antigens, antibodies and associated components of complement C3, C4, C1q. Normally, immune complexes formed in the bloodstream are phagocytosed and destroyed. With an increase in their size (with an excess of antigens and the presence in the structure of IgM, the complement component of C1q), complexes can be deposited in the perivascular space and the cortical layer of the kidneys, causing complement activation and inflammatory processes. Pathological reactions to immune complexes may be due to an increase in the rate of their formation over the rate of elimination, deficiency of one or more complement components, or functional defects of the phagocytic system. Determination of the content of immune complexes in blood serum is important in the diagnosis of acute inflammatory processes and allergic reactions of type III, in which the level of the CEC is increased, as well as in assessing the effectiveness of the treatment.
In autoimmune diseases, auto-antibodies react with tissues that exert a cytotoxic effect, but an immeasurably greater damaging effect is exerted by immune complexes. More than a hundred diseases, mainly due to deposition in various organs, tissues or CEC systems with subsequent activation of complement and cell lysosomes, development of an inflammatory reaction or destruction of tissues under the influence of T-killers and macrophages are described.
An increase in the concentration of the CIC in the blood is possible for the following diseases.
- Acute bacterial, fungal, parasitic and viral infections.
- Autoimmune diseases, collagenoses, rheumatism, glomerulonephritis, allergic alveolitis, vasculitis, Arthus phenomenon.
- Immunocomplex diseases, serum sickness.
- Allergic reactions of type III.
[