title: The dysfunctions of complement factor H in lupus nephritis.
abstract: OBJECTIVE
  Our previous study showed that plasma levels of factor H (FH) were significantly decreased in patients with lupus nephritis and reflected lupus nephritis activity. The aim of this study was to further investigate in vitro biofunctions of plasma FH in patients with lupus nephritis.
  
  
  METHODS
  FH was purified from the first run of plasma exchange in four active lupus nephritis patients and two non-renal involvement systemic lupus erythematosus (SLE) patients, and plasma from two healthy controls. Then, the biofunctions of the purified FH were analyzed. In addition, FH exons sequencing analysis was performed.
  
  
  RESULTS
  Homogeneous FH was purified from the plasma fractions and the purity of the purified FH was comparable to the commercial FH. The abilities of FH binding with C3b and mCRP, and its protecting abilities from the lysis of sheep erythrocytes, from No. 3 and No. 4 lupus nephritis patients, decreased significantly compared with those in normal controls. The purified FH from lupus nephritis patients Nos. 2-4 could not induce the phagocytosis of late apoptotic cells significantly compared with normal controls. All four lupus nephritis patients had the known SNP rs1061147 (SCR5, A307A), rs1061170 (SCR7, Y402H), CM050194 (SCR20, S1191W) and CM010322 (SCR20, V1197A), which might be associated with the above dysfunctions.
  
  
  CONCLUSIONS
  Dysfunctions of FH, including the regulations of complement alternative pathway and the clearance of apoptotic cells, were found in some active lupus nephritis patients, which were associated with their clinical phenotypes. The FH SNPs might contribute to the dysfunctions of FH in patients with lupus nephritis.
authors.affiliation: Renal Division, Department of Medicine, Peking University First Hospital; Institute of Nephrology, Peking University, PR China Key Laboratory of Renal Disease, Ministry of Health of China, PR China; Key Laboratory of CKD Prevention and Treatment, Ministry of Education of China, PR China Institute of Nephrology, Zhongda Hospital, Southeast University, Nanjing, PR China.
authors.forename: F-M
authors.initials: FM
authors.lastname: Wang
authors.affiliation: Renal Division, Department of Medicine, Peking University First Hospital; Institute of Nephrology, Peking University, PR China Key Laboratory of Renal Disease, Ministry of Health of China, PR China; Key Laboratory of CKD Prevention and Treatment, Ministry of Education of China, PR China.
authors.forename: D
authors.initials: D
authors.lastname: Song
authors.affiliation: Renal Division, Department of Medicine, Peking University First Hospital; Institute of Nephrology, Peking University, PR China Key Laboratory of Renal Disease, Ministry of Health of China, PR China; Key Laboratory of CKD Prevention and Treatment, Ministry of Education of China, PR China.
authors.forename: Y
authors.initials: Y
authors.lastname: Pang
authors.affiliation: Department of Nephrology, the First Affiliated Hospital of Chinese PLA General Hospital, Beijing, PR China.
authors.forename: Y
authors.initials: Y
authors.lastname: Song
authors.affiliation: Renal Division, Department of Medicine, Peking University First Hospital; Institute of Nephrology, Peking University, PR China Key Laboratory of Renal Disease, Ministry of Health of China, PR China; Key Laboratory of CKD Prevention and Treatment, Ministry of Education of China, PR China Department of Nephrology, Peking University International Hospital, Beijing, PR China yufengevert1@sina.com songyan0209@163.com.
authors.forename: F
authors.initials: F
authors.lastname: Yu
authors.affiliation: Renal Division, Department of Medicine, Peking University First Hospital; Institute of Nephrology, Peking University, PR China Key Laboratory of Renal Disease, Ministry of Health of China, PR China; Key Laboratory of CKD Prevention and Treatment, Ministry of Education of China, PR China Peking-Tsinghua Center for Life Sciences, Beijing, PR China.
authors.forename: M-H
authors.initials: MH
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D000328:Adult; D002097:C-Reactive Protein / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D003179:Complement C3b / Q000276:immunology / Q000378:metabolism; D017242:Complement Factor H / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D005260:Female; D005820:Genetic Testing; D006801:Humans; D019169:Jurkat Cells; D008180:Lupus Erythematosus, Systemic / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D008181:Lupus Nephritis / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D010587:Phagocytosis; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: C493495:CFH protein, human; D003179:Complement C3b; D017242:Complement Factor H; D002097:C-Reactive Protein
keywords: Factor H; functions; genes; lupus nephritis; single-nucleotide polymorphisms (SNPs)