title: Post-mortem analysis of bone marrow osteoclasts using tartrate-resistant acid phosphatase staining: does histochemistry work and correlate with time since death?
abstract: OBJECTIVE
  In bone marrow (BM) biopsies, tartrate-resistant acid phosphatase (TRAP) staining represents the gold standard for the characterisation of osteoclasts. TRAP is one of the few enzymes that is histochemically detectable on formalin-fixed paraffin-embedded tissue. This study investigated whether TRAP is also able to visualise BM osteoclasts in autopsy tissue. It was hypothesised that, due to a progressive loss of enzymatic activity in osteoclasts post-mortem, TRAP staining could allow the time of death of a patient to be determined.
  
  
  METHODS
  TRAP-stained BM slides of 96 cases including 51 pathology and 23 forensic autopsies and 22 biopsies were histologically evaluated and their staining intensity (SI) semi-quantitatively graded. In the autopsy cases, the results were correlated with the post-mortem interval (PMI, time span in days between death and autopsy).
  
  
  RESULTS
  TRAP staining intensities (TRAP-SIs) did not differ between men and women and showed a steady decrease with age. TRAP-SIs were significantly stronger in biopsies than in autopsy cases. Among the autopsies, TRAP-SIs were highly variable and not dependent on PMI, except for three forensic cases with PMI ≥7 days which showed a complete loss of TRAP stainability. On the whole, the TRAP-SIs of pathology and forensic cases did not differ significantly.
  
  
  CONCLUSIONS
  This study clearly shows that BM osteoclasts stay TRAP-positive for 7 days post-mortem, although with markedly reduced TRAP-SIs compared with biopsies. Since TRAP-SIs were not correlated with the duration of PMI, TRAP staining of BM osteoclasts cannot serve as a tool to determine the time of death of a patient.
authors: Institute of Pathology, Freiburg University Medical Center, Freiburg, Germany. joboehm.email@yahoo.de
authors: Joachim
authors: J
authors: Boehm
authors: Ulrike
authors: U
authors: Schmidt
authors: Michéle
authors: M
authors: Porsche
authors: Juergen
authors: J
authors: Veeck
authors: Hans-Eckart
authors: HE
authors: Schaefer
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy / Q000379:methods*; D001854:Bone Marrow Cells / Q000201:enzymology / Q000473:pathology*; D005260:Female; D005554:Forensic Medicine / Q000379:methods*; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010010:Osteoclasts / Q000201:enzymology / Q000473:pathology*; D000071681:Tartrate-Resistant Acid Phosphatase; D013997:Time Factors; D055815:Young Adult
chemical_list: D007527:Isoenzymes; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase