title: Membrane attack complex generation increases as a function of time in stored blood.
abstract: OBJECTIVE
  To determine if the complement system, a potent mediator of inflammation, contributes to haemolysis during red blood cell (RBC) storage.
  
  
  BACKGROUND
  RBCs in storage undergo structural and biochemical changes that may result in adverse patient outcomes post-transfusion. Complement activation on leukodepletion and during storage may contribute to the RBC storage lesion.
  
  
  METHODS
  We performed a cross-sectional analysis of aliquots of leukoreduced RBC units, stored for 1-6 weeks, for the levels of C3a, C5a, Bb, iC3b, C4d and C5b-9 [membrane attack complex (MAC)] by enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  We observed that only MAC levels significantly increased in RBC units as a function of storage time. We also observed that the level of C5b-9 bound to RBCs increased as a function of storage time.
  
  
  CONCLUSIONS
  MAC levels increased over time, suggesting that MAC is the primary complement-mediated contributor to changes in stored RBCs. Inhibition of the terminal complement pathway may stabilise RBC functionality and extend shelf life.
authors.affiliation: Department of Microbiology.
authors.forename: X
authors.initials: X
authors.lastname: Hu
authors.forename: R P
authors.initials: RP
authors.lastname: Patel
authors.forename: J A
authors.initials: JA
authors.lastname: Weinberg
authors.forename: M B
authors.initials: MB
authors.lastname: Marques
authors.forename: T N
authors.initials: TN
authors.lastname: Ramos
authors.forename: S R
authors.initials: SR
authors.lastname: Barnum
mesh_terms: D001793:Blood Preservation; D015938:Complement Membrane Attack Complex / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D004912:Erythrocytes / Q000166:cytology* / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D013997:Time Factors
chemical_list: D015938:Complement Membrane Attack Complex
keywords: complement; extrinsic protease pathway; membrane attack complex