title: The effect of cryopreservation on cell viability and hormone secretion in human parathyroid tissue.
abstract: BACKGROUND
  To explain the decreased success of cryopreserved versus fresh parathyroid autotransplants, we investigated the effect of cryopreservation on parathyroid function.
  
  
  METHODS
  Parathyroid cryopreserved tissue from surgical specimens of 18 patients was analyzed in a comparative fashion with 10 fresh abnormal glands. Cell viability was evaluated by a double-fluorescence technique, and parathyroid hormone secretion was detected from individually dispersed parathyroid cells with the reverse hemolytic plaque assay. The plaque area reflected the amount of parathyroid hormone secreted by each cell, and the percentage of plaque-forming cells represented the number of secreting cells. Feedback regulatory mechanisms remained intact for both fresh and cryopreserved tissue as shown over a wide range of calcium concentrations.
  
  
  RESULTS
  The percentage of viable cells from fresh and cryopreserved tissue was always in excess of 88%. No significant difference was noted in the percentage of plaque-forming cells nor the amount of hormone released per individual cell comparing fresh and cryopreserved glands (6 months to 2 years). Specifically, at physiologic calcium concentrations no significant differences existed in the secretory behavior between fresh and cryopreserved tissue.
  
  
  CONCLUSIONS
  Without showing decreased viability or parathyroid hormone secretion after cryopreservation, the cause of graft failure in cryopreserved tissue still remains unknown.
authors.affiliation: Department of Surgery, Mayo Clinic, Rochester, MN 55905.
authors.forename: M F
authors.initials: MF
authors.lastname: Herrera
authors.forename: C S
authors.initials: CS
authors.lastname: Grant
authors.forename: J A
authors.initials: JA
authors.lastname: van Heerden
authors.forename: D
authors.initials: D
authors.lastname: Jacobsen
authors.forename: A
authors.initials: A
authors.lastname: Weaver
authors.forename: L A
authors.initials: LA
authors.lastname: Fitzpatrick
mesh_terms: D002118:Calcium / Q000494:pharmacology; D002470:Cell Survival; D015925:Cryopreservation; D006801:Humans; D009994:Osmolar Concentration; D010280:Parathyroid Glands / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D010281:Parathyroid Hormone / Q000378:metabolism*; D013997:Time Factors
chemical_list: D010281:Parathyroid Hormone; D002118:Calcium