title: Removal of cytokines and activated complement components in an experimental model of continuous plasma filtration coupled with sorbent adsorption.
abstract: BACKGROUND
  Sepsis is associated with enhanced cytokine production. Here, we examined the in vitro removal of plasma cytokines during continuous plasmafiltration coupled with sorbent adsorption.
  
  
  METHODS
  Proinflammatory (tumour necrosis factor-alpha, interleukins-1, -8) and anti-inflammatory (interleukin 1 receptor antagonist, soluble tumour necrosis factor receptor type I and II) cytokines in whole blood spiked with Escherichia coli endotoxin were determined during 2-h recirculation in the ultrafiltrate (condition A), plasma filtrate (condition B), before and after different sorbents (of the Amberlite-, Amberchrome- Ambersorb -type and charcoal). We studied the maximal adsorbing capacity, the 1% leakage test for cytokines and C3a des Arg and the adsorption of complement-dependent leukocyte chemiluminescence. Plasma proteins eluted from the resins were examined by sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting with an anti-human alpha2-macroglobulin.
  
  
  RESULTS
  In condition B, we observed a 40- and 121-fold % increase (vs condition A) in the removed mass and clearance of tumour necrosis factor-alpha. For all other cytokines, the removed mass and the clearance increased from 2.3- up to 6-fold. The Amberchrome but not the Amberlite or Ambersorb resins could remove the highest amount of cytokines and could reduce complement-dependent chemiluminescence. Two protein bands of approximately 400,000 D and 200,000 D were eluted only from Amberchrome resins and immunoprecipitated by anti-human alpha2-macroglobulin and anti-human C3c antibodies, respectively.
  
  
  CONCLUSIONS
  These studies suggest an efficient removal of cytokines in continuous plasmafiltration with sorbent adsorption. The binding of alpha2-macroglobulin, a carrier of cytokines in plasma, might be a additional mechanism in the removal of cytokines from plasma.
authors.affiliation: Clinical and Laboratory Research Department, Bellco S.p.A., Mirandola (Modena) Italy.
authors.forename: C
authors.initials: C
authors.lastname: Tetta
authors.forename: J M
authors.initials: JM
authors.lastname: Cavaillon
authors.forename: M
authors.initials: M
authors.lastname: Schulze
authors.forename: C
authors.initials: C
authors.lastname: Ronco
authors.forename: P M
authors.initials: PM
authors.lastname: Ghezzi
authors.forename: G
authors.initials: G
authors.lastname: Camussi
authors.forename: A M
authors.initials: AM
authors.lastname: Serra
authors.forename: F
authors.initials: F
authors.lastname: Curti
authors.forename: G
authors.initials: G
authors.lastname: Lonnemann
mesh_terms: D000327:Adsorption; D001779:Blood Coagulation Factors / Q000302:isolation & purification; D001798:Blood Proteins / Q000302:isolation & purification; D003165:Complement System Proteins / Q000302:isolation & purification*; D016207:Cytokines / Q000097:blood / Q000302:isolation & purification*; D006440:Hemofiltration / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D066298:In Vitro Techniques; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000097:blood / Q000302:isolation & purification; D016209:Interleukin-8 / Q000097:blood / Q000302:isolation & purification; D008163:Luminescent Measurements; D009504:Neutrophils / Q000378:metabolism; D010949:Plasma / Q000378:metabolism; D018805:Sepsis / Q000097:blood / Q000628:therapy; D012795:Sialoglycoproteins / Q000097:blood / Q000302:isolation & purification; D014409:Tumor Necrosis Factor-alpha / Q000302:isolation & purification; D014462:Ultrafiltration
chemical_list: D001779:Blood Coagulation Factors; D001798:Blood Proteins; D016207:Cytokines; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D016209:Interleukin-8; D012795:Sialoglycoproteins; D014409:Tumor Necrosis Factor-alpha; D003165:Complement System Proteins