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Home › Research › Immune System: Complement C3a
Immune System

Complement C3a

Optimal result: 69.2 – 273.6 ng/mL
By Healthmatters Editorial Team
Peer-reviewed sources

Complement C3a was found to be elevated in patients with:

- Inflammation (such as asthma)

- Autoimmune diseases [C3a levels were increased in patients with severe and moderately active lupus (SLE).]

- Chronic hepatitis C, and HCV-related hepatitis cell carcinoma.

- In a recent study, all acute Lyme disease patients had elevated levels of C3a, hence C3a (and C4a) can be regarded as an early marker of acute lyme disease in patients seen shortly after tick bite.

- Smoking

- Stroke

- Chronic hepatitis/liver cancer

- Colon cancer

- Pancreas inflammation

Low C3a levels may increase the risk of infections and inflammation.

- An inherited deficiency of C3 predisposes patients to frequent bouts of bacterial infections.

- Gestational Diabetes - this occurs when healthy women develop high blood sugar levels during pregnancy.

Although C3a was shown to be elevated in a cohort of early, acute Lyme disease patients, it appears to be normal in chronic Lyme patients.

C3 is the most abundant protein of the complement system. C3 can be cleaved in two divalent fragments, where C3b is the larger fragment. C3a is the smaller fragment that is released into the surrounding fluids. C3a can bind to receptors on basophils and mast cells triggering them to release their vasoactive amines (e.g. histamine). Because of the role of these biomarkers in anaphylaxis, C3a is called an anaphylatoxin. C3a is one of the most potent constrictors of smooth muscle cells. C3a has been shown to be a multifunctional pro-inflammatory mediator.

C3 is the most abundant protein of the complement system. C3 can be cleaved in two divalent fragments, where C3b is the larger fragment. C3a is the smaller fragment that is released into the surrounding fluids. C3a can bind to receptors on basophils and mast cells triggering them to release their vasoactive amines (e.g. histamine). Because of the role of these biomarkers in anaphylaxis, C3a is called an anaphylatoxin. C3a is one of the most potent constrictors of smooth muscle cells. C3a has been shown to be a multifunctional pro-inflammatory mediator.

- C3a may be an indicator of a Lyme-related issue if the Lyme is in an acute stage.

- Although C3a was shown to be elevated in a cohort of early, acute Lyme disease patients, it appears to be normal in chronic Lyme patients. 

- In mold, C3a is normal and C4a is high.

References:

  • https://www.ncbi.nlm.nih.gov/pubmed/18270493
  • https://www.ncbi.nlm.nih.gov/pubmed/19140878
  • https://onlinelibrary.wiley.com/doi/pdf/10.1002/art.1780290905
  • https://www.ncbi.nlm.nih.gov/pubmed/3263085
  • https://www.karger.com/Article/FullText/328238
  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1959484/
  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4753731/
  • https://www.ncbi.nlm.nih.gov/pubmed/16586433
  • https://www.ncbi.nlm.nih.gov/pubmed/20012107
  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2532535/
  • https://www.ncbi.nlm.nih.gov/pubmed/25520093
  • https://www.ncbi.nlm.nih.gov/pubmed/19601884
  • https://www.ncbi.nlm.nih.gov/pubmed/21615487
  • https://jacewellness.com/articles/Lab%20Testing%20for%20water%20damaged%20building%20illness.pdf 
  • https://www.survivingmold.com/docs/Resources/Shoemaker%20Papers/Lyme_acute_C4a_1_08_glovsky.pdf

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