Nutrition Guide

Properdin was discovered in 1954 by Dr. Louis Pillemer of the Institute of Pathology (now the Department of Pathology at Case Western Reserve University).

t is known that it participates in some specific immune responses. It plays a part in tissue inflammation as well as the engulfing of pathogens by phagocytes. In addition it is known to help to neutralize some viruses.

As a component of the alternThe alternative pathway is not dependent on antibodies. This branch of the complement system is activated by IgA immune complexes and bacterial endotoxins, polysaccharides, and cell walls, and results in producing anaphylatoxins, opsonins, chemotactic factors, and the membrane attack complex, all of which help fight pathogens.another protein, C3b, to stabilize the alternative C3 convertase (C3bBb) that then cleaves more C3.

Properdin or factor P is a globulin protein found in the blood serum of higher animals. In the complement system, an innate-immunity series of proenzymes dissolved in the circulation, it is also called “Factor P”

Mannose-binding protein-associated serine protease are serine proteases involved in the complement system.

Types include:
MASP1 (protein)
MASP2 (protein)

MASP2 is a protein involved in the complement system.

Mannose-associated serine protease 1 (MASP1) is a human gene.[1][2]

The protein encoded by this gene is involved in the lectin pathway of the complement system and is responsible for cleaving C4 and C2 to form C4b2a, a C3-convertase.[3]

Pío R, Elsasser TH, Martínez A, Cuttitta F (2002). “Identification, characterization, and physiological actions of factor H as an adrenomedullin binding protein present in human plasma.”. Microsc. Res. Tech. 57 (1): 23–7. doi:10.1002/jemt.10047. PMID 11921353.
Rodríguez de Córdoba S, Esparza-Gordillo J, Goicoechea de Jorge E, et al. (2004). “The human complement factor H: functional roles, genetic variations and disease associations.”. Mol. Immunol. 41 (4): 355–67. doi:10.1016/j.molimm.2004.02.005. PMID 15163532.
Walport MJ (2001). “Complement. First of two parts.”. N Engl J Med. 344 (14): 1058–66. doi:10.1056/NEJM200104053441406. PMID 11287977.
Walport MJ (2001). “Complement. Second of two parts.”. N Engl J Med. 344 (15): 1140–4. doi:10.1056/NEJM200104123441506. PMID 11297706

Pangburn, M.K. Host recognition and target differentiation by factor H, a regulator of the alternative pathway of complement. Immunopharmacology 49, 149-57 (2000).
Aslam M. & Perkins S.J. Folded-back solution structure of monomeric factor H of human complement by synchrotron X-ray and neutron scattering, analytical ultracentrifugation and constrained molecular modelling. J Mol Biol. 309(5), 1117-38 (2001).
Kirkitadze, M.D. & Barlow, P.N. Structure and flexibility of the multiple domain proteins that regulate complement activation. Immunol Rev 180, 146-61 (2001).
Hageman, G.S. et al. A common haplotype in the complement regulatory gene factor H (HF1/CFH) predisposes individuals to age-related macular degeneration. Proc Natl Acad Sci U S A 102, 7227-32. (2005).
Kardys, I. et al. A common polymorphism in the complement factor h gene is associated with increased risk of myocardial infarction the rotterdam study. J Am Coll Cardiol. 47, 1568-75. (2006).
Herbert, A.P. et al. Structure shows that a glycosaminoglycan and protein recognition site in factor H is perturbed by age-related macular degeneration-linked single nucleotide polymorphism. J Biol Chem. 282(26), 18960-8. (2007).
Hocking, H.G et al. Structure of the N-terminal region of complment factor H and conformational implications of disease-linked sequence variations. “J Biol Chem” Feb 5 Epub ahead of print (2008).

Haemolytic uraemic syndrome (HUS) is a disease associated with microangiopathic haemolytic anemia, thrombocytopenia and acute renal failure. A rare subset of this disease (referred to as atypical haemolytic uraemic syndrome, aHUS), has been strongly linked to mutations in genes of the complement system (including factor H, factor I and membrane cofactor protein), with the factor H mutations being the most numerous. These factor H mutations tend to congregate towards the C-terminus of factor H—a region responsible for discriminating self from non-self and have been shown to disrupt heparin and C3d binding.

Recently is was discovered that about 35% of individuals carry at an at-risk single nucleotide polymorphism (SNP) in one or both copies of their factor H gene. Homozygous individuals have an approximately sevenfold increased chance of developing age-related macular degeneration, while heterozygotes have a two-to-threefold increased likelihood of developing the disease. This SNP, located in CCP module 7 of factor H, has been shown to affect the interactions between factor H and both C-reactive protein and heparin indicating a causal relationship between the SNP and disease.