title: Development of a novel fragments absorbed immunocapture enzyme assay system for tartrate-resistant acid phosphatase 5b.
abstract: BACKGROUND
  Osteoclastic activity is mainly assessed by measuring urinary markers. To correct for differences in renal clearance, the levels of urinary markers are usually corrected by the urine creatinine concentration. Therefore, alternative serum markers to evaluate osteoclastic activity are required. We developed a novel system for the determination of serum tartrate-resistant acid phosphatase 5b (TRACP5b) activity to evaluate osteoclastic activity.
  
  
  METHODS
  Two unique monoclonal antibodies were generated and the specificity was tested using a surface enhanced laser desorption/ionization time-of-flight mass spectroscopy (SELDI TOF-MS). A novel fragments absorbed immunocapture enzymatic assay (FAICEA) method was developed using 2 monoclonal antibodies.
  
  
  RESULTS
  FAICEA gave a sensitivity 0.1 U/l, linearity of 0.1-28 U/l, recovery 92-103%, inter-assay CV 2.95% and intra-assay CV 2.15%. Unlike other TRACP5b assay systems, FAICEA avoided interference from TRACP 5a.
  
  
  CONCLUSIONS
  According to the FAICEA, postmenopausal women had higher TRACP5b concentrations than younger women. The results show that TRACP5b is a novel bone resorption marker in serum.
authors.affiliation: Department of Molecular Diagnosis (F8), Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chiba City, Chiba 260-8670, Chiba, Japan. OOHASHIT@jn.nittobo.co.jp
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Ohashi
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Igarashi
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Mochizuki
authors.forename: Toshihide
authors.initials: T
authors.lastname: Miura
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Inaba
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Katayama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tomonaga
authors.forename: Fumio
authors.initials: F
authors.lastname: Nomura
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis / Q000097:blood* / Q000276:immunology; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000302:isolation & purification; D000918:Antibody Specificity; D001862:Bone Resorption / Q000097:blood* / Q000175:diagnosis; D002460:Cell Line; D002648:Child; D005260:Female; D005269:Femur / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007128:Immunoglobulin Fragments / Q000737:chemistry*; D007527:Isoenzymes / Q000032:analysis / Q000097:blood* / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008875:Middle Aged; D010010:Osteoclasts / Q000502:physiology; D040081:Protein Array Analysis; D017678:Sex Distribution; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D000071681:Tartrate-Resistant Acid Phosphatase
chemical_list: D000911:Antibodies, Monoclonal; D007128:Immunoglobulin Fragments; D007527:Isoenzymes; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase