title: Osteoprotegerin and receptor activator of nuclear factor-kappaB ligand (RANKL) in the serum of healthy adults.
abstract: OBJECTIVE
  Osteoprotegerin and the receptor activator of the nuclear factor-kappaB ligand (RANKL) are decisive factors for maintaining the balance between bone formation and bone resorption. As new, sensitive ELISAs have been developed recently, reference serum ranges should be established to use these analytes for possible diagnostic purposes.
  
  
  METHODS
  Measurements were performed in serum samples of 142 healthy adults (82 women, 60 men) between 20 and 70 years of age (mean age: 46 years) using ELISA kits from Immundiagnostik, Bensheim, Germany.
  
  
  RESULTS
  Serum concentrations of osteoprotegerin were age and gender independent and showed a Gaussian distribution, while RANKL concentrations were also age independent but differed between males and females, with a non-Gaussian distribution. For osteoprotegerin a gender-independent upper 97.5 percentile limit of 3.6 pmol/L was calculated while the corresponding limits for RANKL and the ratio of RANKL to osteoprotegerin amounted to 3.29 pmol/L and 2.78 in women and 1.66 pmol/L and 2.18 in men, respectively.
  
  
  CONCLUSIONS
  Both osteoprotegerin and RANKL were quantifiable in serum of healthy adults, which means that these compounds can be used as potential diagnostic tools.
authors.affiliation: Department of Urology, University Hospital Charité, Humboldt University Berlin, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Jung
authors.forename: M
authors.initials: M
authors.lastname: Lein
authors.forename: K v
authors.initials: Kv
authors.lastname: Hösslin
authors.forename: A
authors.initials: A
authors.lastname: Grosse
authors.forename: S
authors.initials: S
authors.lastname: Roth
authors.forename: K
authors.initials: K
authors.lastname: Possinger
authors.forename: D
authors.initials: D
authors.lastname: Lüftner
mesh_terms: D000328:Adult; D000368:Aged; D002352:Carrier Proteins / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood*; D008875:Middle Aged; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000097:blood*; D018124:Receptors, Tumor Necrosis Factor; D012016:Reference Values; D012737:Sex Factors
chemical_list: D002352:Carrier Proteins; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human