<< Back to the abstract archive
Fat graft retention in pedal fat grafting: association with CD34+ adipose stem cells and collagen
Wang S, James IB, DiBernardo G, Lannau B, Grybowski D, Zhang W, Gusenoff BR, Marra K, Gusenoff JA.
University of Pittsburgh, Department of Plastic Surgery
2017-02-15
Presenter: Sheri Wang
Affidavit:
This research has not been previously published.
Director Name: JPRubin
Author Category: Medical Student
Presentation Category: Basic Science Research
Abstract Category: General Reconstruction
INTRODUCTION: Fat grafting is an important and versatile procedure, but is limited by unpredictable volume retention. Hazen et al. has demonstrated in mice that high-density fat is associated with increased graft retention, higher progenitor concentration, and fewer collagen bands. Similarly, previous work by our group demonstrated that CD34+ adipose stem cells (ASCs) are predictive of fat graft retention in mice. We hypothesize that CD34+ ASCs are correlated with increased submetatarsal fat graft retention and lower collagen content in humans.
METHODS: Fat was harvested by manual liposuction and processed by standard Coleman technique from 24 patients undergoing fat grafting to the forefoot as part of a randomized cross-over clinical trial. Ultrasound-assessed submetatarsal tissue thickness was obtained at baseline, 6mo, & 12mo visits. Processed lipoaspirate was returned to the lab for SVF isolation, flow cytometry, and collagen assessment using Western blot.
RESULTS: Average age was 63.6+/-6.7, and average BMI was 26.1+/-4.6. No patients were diabetic. The proportion of CD34+ ASCs in the fat graft and viability of the SVF isolate were correlated with significantly improved retention of tissue thickness at 6mo (p=0.044, p=0.033 respectively) but not at 12mo. Fat grafts with lower collagen1 concentration were associated with significantly greater SVF viability and CD34+ ASC content (p=0.046, p=0.005 respectively).
CONCLUSIONS: Volume loss after fat grafting remains a perplexing problem. The inverse association between collagen vs ASC content and SVF viability merits further study, particularly given the fact that ASC content and SVF viability predicted retention of tissue thickness at 6mo in grafted feet.
