title: Change of the metabolomic profile during short-term mononuclear cell storage.
abstract: OBJECTIVE
  Short-term storage of leukapheresis products used for immunotherapeutic mononuclear cell (MNC) products is a frequent event. The analysis of time-related metabolic patterns enables the characterization of storage-related effects in MNCs and the hypothesis-based optimization of the MNC medium.
  
  
  METHODS
  The MNC products from seven leukapheresis procedures were stored within a closed bag system for 48 h. Concentrations of amino acids, biogenic amines, phospho- and sphingolipids and hexoses in the medium were measured by targeted metabolomics. The viability of MNC subpopulations was assayed by Annexin V (AnV) and JC-1 staining.
  
  
  RESULTS
  Glucose depletion and a significant change of the acylcarnitine profile are early events within the first 24 h of storage. In contrast, for most amino acids, the maximum increase was observed at 48 h of storage as mirrored by an increase in the amino acid levels by a mean factor of 1·2 (1·3, 2·0) after 6 h (24 h, 48 h, respectively). This was except for the concentrations of glutamine and lysine, which did not change significantly. The taurine concentration showed a twofold increase within the first 24 h and remained constant thereafter. The steepest increase in AnV+and 7-AAD+CD4+T cells was found between 24 and 48 h.
  
  
  CONCLUSIONS
  The time-course of apoptosis and metabolic patterns in the MNC products demonstrate that 24 h of storage is a decisive time-point, as afterwards key metabolic pathways showed nonlinear detrimental changes. Optimization of storage by supplementation of specific substrates demands therefore an early intervention.
authors.affiliation: Department of Transfusion Medicine and Haemostaseology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: P A
authors.initials: PA
authors.lastname: Steininger
authors.affiliation: Department of Transfusion Medicine and Haemostaseology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: E F
authors.initials: EF
authors.lastname: Strasser
authors.affiliation: Department of Transfusion Medicine and Haemostaseology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Ziehe
authors.affiliation: Department of Transfusion Medicine and Haemostaseology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Eckstein
authors.affiliation: Department of Paediatrics and Adolescent Medicine, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Rauh
mesh_terms: D000588:Amines / Q000032:analysis; D000596:Amino Acids / Q000032:analysis; D017209:Apoptosis; D001793:Blood Preservation; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000378:metabolism; D002331:Carnitine / Q000031:analogs & derivatives / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007937:Leukapheresis; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000378:metabolism*; D055432:Metabolomics; D010743:Phospholipids / Q000032:analysis; D013107:Sphingolipids / Q000032:analysis; D053719:Tandem Mass Spectrometry; D013997:Time Factors
chemical_list: D000588:Amines; D000596:Amino Acids; D010743:Phospholipids; D013107:Sphingolipids; C116917:acylcarnitine; D005947:Glucose; D002331:Carnitine
keywords: apoptosis; cellular therapy; metabolomics; mononuclear cell apheresis; short-term storage