Cited by 91Complement system in diseasesCoagulation, Bradykinin, Polyphosphates, and AngioedemaBiomarkers in Disease Mechanisms

Properdin and factor h: Opposing players on the alternative complement pathway “see-saw”

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Kouser, Lubna, Abdul-Aziz, Munirah, Nayak, Annapurna, Stover, Cordula M., Sim, Robert B., Kishore, Uday·2013·Frontiers in Immunology

Abstract

Properdin and factor H are two key regulatory proteins having opposite functions in the alternative complement pathway. Properdin up-regulates the alternative pathway by stabilizing the C3bBb complex, whereas factor H downregulates the pathway by promoting proteolytic degradation of C3b. While factor H is mainly produced in the liver, there are several extrahepatic sources. In addition to the liver, factor H is also synthesized in fetal tubuli, keratinocytes, skin fibroblasts, ocular tissue, adipose tissue, brain, lungs, heart, spleen, pancreas, kidney, muscle, and placenta. Neutrophils are the major source of properdin, and it is also produced by monocytes, T cells and bone marrow progenitor cell line. Properdin is released by neutrophils from intracellular stores following stimulation by N-formyl-methionine-leucine-phenylalanine (fMLP) and tumor necrosis factor alpha (TNF-α). The HEP G2 cells derived from human liver has been found to produce functional properdin. Endothelial cells also produce properdin when induced by shear stress, thus is a physiological source for plasma properdin. The diverse range of extrahepatic sites for synthesis of these two complement regulators suggests the importance and need for local availability of the proteins. Here, we discuss the significance of the local synthesis of properdin and factor H. This assumes greater importance in view of recently identified unexpected and novel roles of properdin and factor H that are potentially independent of their involvement in complement regulation.

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Crossref · 10.3389/fimmu.2013.00093

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  • Most complement proteins are produced in the liver, while others (C1q, C7, Factor D, and properdin) are produced at extrahepatic sites by various cells, including monocytes, macrophages, and glial and endothelial cells.

    “While most complement proteins are produced in the liver, others (such as C1q, C7, Factor D, and properdin) are produced at extrahepatic sites by various cells, including monocytes, macrophages, and glial and endothelial cells [7,204,205].”

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Authors
Kouser, L., Abdul-Aziz, M., Nayak, A., Stover, C. M., Sim, R. B., & Kishore, U.
Affiliations
  • Brunel University of London (GB)
  • University of Oxford (GB)
  • University of Leicester (GB)
  • Kingston University London (GB)
Corresponding author
Kishore, Uday
Venue
Frontiers in Immunology
Published
2013
Volume
4
Pages
93-93
ISSN
1664-3224 (ISSN-L)
OpenAlex
W2056545631
Cited by
91
References
135
Citations by year
2026: 5 · 2025: 6 · 2024: 6 · 2023: 9 · 2022: 7 · 2021: 9 · 2020: 11 · 2019: 5 · 2018: 9 · 2017: 9 · 2016: 5 · 2015: 6 · 2014: 4
FWCI
2.76
Type
journal article
Language
en
Open access
Licence
cc-by
Locations
  • Frontiers in Immunology (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Brunel University Research Archive (BURA) (Brunel University London) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
  • Leicester Research Archive (University of Leicester) (submittedVersion, other-oa)
Funders
  • Ministry of Higher Education, Malaysia
  • Universiti Sains Malaysia
Topics
  • Life Sciences › Immunology and Microbiology › Immunology › Complement system in diseases
  • Health Sciences › Medicine › Genetics › Coagulation, Bradykinin, Polyphosphates, and Angioedema
  • Life Sciences › Immunology and Microbiology › Immunology › Biomarkers in Disease Mechanisms
Keywords
properdin, complement factor H, alternative complement pathway, complement regulation, C3b degradation, neutrophils, endothelial cells, shear stress, fMLP, TNF-α, HepG2 cells

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