title: Effects of intersyringe processing on adipose tissue and its cellular components: implications in autologous fat grafting.
abstract: BACKGROUND
  Autologous fat grafting is a popular technique in plastic surgery. A mechanical processing method is used to facilitate fat injection. No study has investigated whether this process affects cell quality and preservation of biological functionality. This study analyzed the influence of quick mechanical processing through two interconnected small-diameter syringes ("shuffling") on both structure and viability of fat tissue, and on viability, clonogenicity, and differentiation of the freshly isolated stromal vascular fraction.
  
  
  METHODS
  Lipoaspiration was performed in six healthy donors, followed by shuffling the fat either zero, five, or 30 times between two 10-cc syringes. Thereafter, fat was applied through a 1.5-mm cannula as in a clinical setting for autologous fat grafting. Analysis of different treatment conditions was conducted. Immunofluorescent staining allowed assessment of morphology, viability, composition, and damage of the tissue. The stromal vascular fraction was examined for isolation yield, viability, clonogenicity, and differentiation capacity.
  
  
  RESULTS
  The process of shuffling changed the macroscopic but not the microscopic structure of the lipoaspirated fat. No difference in cell number, viability, number of lipid droplets, vascular architecture, or ratio of cell composition was found. Analysis of the stromal vascular fraction, apart from large interdonor variability, did not show a significant change in isolation yield, viability, clonogenicity, or adipogenic differentiation capacity of the expanded cells.
  
  
  CONCLUSIONS
  The mechanical procedure of shuffling lipoaspirated fat does not alter its tissue viability or its microscopic structure. The absence of impact on the stromal vascular fraction in the assessed parameters suggests that shuffling can be executed according to surgical needs.
authors.affiliation: Basel, Switzerland From the Division of Plastic, Reconstructive, Aesthetic and Hand Surgery, Department of Surgery, and Tissue Engineering, Institute for Surgical Research and Hospital Management, Department of Surgery, University Hospital of Basel.
authors.forename: Rik
authors.initials: R
authors.lastname: Osinga
authors.forename: Nadia R
authors.initials: NR
authors.lastname: Menzi
authors.forename: Laurent A H
authors.initials: LAH
authors.lastname: Tchang
authors.forename: Daniel
authors.initials: D
authors.lastname: Caviezel
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Kalbermatten
authors.forename: Ivan
authors.initials: I
authors.lastname: Martin
authors.forename: Dirk J
authors.initials: DJ
authors.lastname: Schaefer
authors.forename: Arnaud
authors.initials: A
authors.lastname: Scherberich
authors.forename: Rene D
authors.initials: RD
authors.lastname: Largo
mesh_terms: D017667:Adipocytes / Q000637:transplantation*; D000273:Adipose Tissue / Q000637:transplantation*; D000368:Aged; D000704:Analysis of Variance; D002470:Cell Survival; D005260:Female; D006085:Graft Survival; D064368:Healthy Volunteers; D006801:Humans; D015187:Lipectomy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D017154:Stromal Cells / Q000166:cytology / Q000502:physiology; D013518:Surgery, Plastic / Q000379:methods; D016378:Tissue Transplantation / Q000379:methods; D020858:Tissue and Organ Harvesting / Q000379:methods*; D014182:Transplantation, Autologous