title: Serum-free non-toxic freezing solution for cryopreservation of human adipose tissue-derived mesenchymal stem cells.
abstract: OBJECTIVE
  To develop a cost-effective, non-toxic and xeno-free freezing solution for the preservation of adipose tissue-derived stem cells (hADSC) with a long shelf-life.
  
  
  RESULTS
  The potential of various hydrocolloids and organic osmolytes as cryoprotectants and individual components of phosphate buffered saline (PBS) as carrier media were evaluated to formulate a freezing solution for the cryopreservation of hADSCs. Among the hydrocolloids, the highest viability, 55 %, was achieved with post-thawed (after 48 h storage at -80 °C) hADSCs cryopreserved in 10 % (v/v) polyvinylpyrrolidone (PVP) using PBS as carrier media. 0.9 % NaCl was a superior carrier medium resulting an enhanced cell viability (70 %) when used in 10 % PVP than other components of PBS. A higher cell viability (81 %) was achieved when 10 % PVP/0.9 % NaCl was supplemented with 60 mM ectoin. The cryopreserved cells retained normal cytoskeletal distribution pattern and adipogenic and osteogenic differentiation ability during 14 and 21 days of incubation.
  
  
  CONCLUSIONS
  A serum-free and non-toxic 10 % PVP/0.9 % NaCl/60 mM ectoin freezing solution was developed for cryopreservation of hADSC for application in tissue engineering and regenerative medicine.
authors.affiliation: Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, 769008, India.
authors.forename: Sirsendu Sekhar
authors.initials: SS
authors.lastname: Ray
authors.affiliation: Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, 769008, India. kpr@nitrkl.ac.in.
authors.forename: Krishna
authors.initials: K
authors.lastname: Pramanik
authors.affiliation: Department of Mechanical Engineering, National Institute of Technology, Rourkela, 769008, India.
authors.forename: Sunil Kumar
authors.initials: SK
authors.lastname: Sarangi
authors.affiliation: Jeevan Memorial Hospital, Raipur, India.
authors.forename: Nirved
authors.initials: N
authors.lastname: Jain
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D015925:Cryopreservation / Q000379:methods*; D005615:Freezing; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology*
keywords: Adipose-derived stem cells; Cryopreservation; Freezing solution; Hydrocolloids; Organic osmolytes; Serum-free