Cutting edge: localization of the host recognition functions of complement factor H at the carboxyl-terminal: implications for hemolytic uremic syndrome.
Incidents of hemolytic uremic syndrome (HUS) include a subset of patients that exhibit mutations in C factor H. These mutations cluster in the C-terminal domains of factor H where previous reports have identified polyanion and C3b-binding sites. In this study, we show that recombinant human factor H with deletions at the C-terminal end of the protein loses the ability to control the spontaneous activation of the alternative C pathway on host-like surfaces. For the pathology of HUS, the findings imply that mutations that disrupt the normal functions of the C-terminal domains prevent host polyanion recognition. The resulting uncontrolled activation of complement on susceptible host tissues appears to be the initiating event behind the acute renal failure of familial HUS patients.
Pangburn
Michael K
MK
Department of Biochemistry, University of Texas Health Science Center, Tyler 75708, USA. michael.pangburn@uthct.edu
D000818:Animals; D017242:Complement Factor H / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D003170:Complement Pathway, Alternative / Q000235:genetics / Q000276:immunology; D006461:Hemolysis / Q000235:genetics / Q000276:immunology; D006463:Hemolytic-Uremic Syndrome / Q000235:genetics / Q000276:immunology*; D006801:Humans; D016297:Mutagenesis, Site-Directed; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D000071228:Polyelectrolytes; D011108:Polymers / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000235:genetics; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D017384:Sequence Deletion / Q000276:immunology; D012756:Sheep
D017242:Complement Factor H; D010446:Peptide Fragments; D000071228:Polyelectrolytes; D011108:Polymers; D011994:Recombinant Proteins; C493495:CFH protein, human