Nanofat Cell Aggregates: A Nearly Constitutive Stromal Cell Inoculum for Regenerative Site-Specific Therapies.

BACKGROUND: Recent technology developed by Tulip Medical Products allows clinicians to mechanically disaggregate fat tissue into small fat particles known as nanofat. The present study aimed to evaluate the cell yield obtained from nanofat generation in comparison to traditional methods involving enzymatic dissociation (stromal vascular fraction). METHODS: Nanofat preparations were characterized by cell content and viability, based on DNA quantification and image cytometry, respectively. DNA analysis was also used to determine the cell content in unprocessed dry lipoaspirate and native adipose tissue (excised adipose tissue). To evaluate cell yield, the authors compared the number of cells recovered from 1 g of lipoaspirate between stromal vascular fraction and nanofat preparations, and subsequently determined the final cell inoculum obtained following their respective protocols. RESULTS: The data showed that nanofat samples presented a cell burden of 7.3 million cells/g, close to 80 percent of unprocessed dry lipoaspirate, and 70 percent of native excised adipose tissue. Moreover, cell viability was not altered by mechanical disaggregation in nanofat samples compared to unprocessed dry lipoaspirate. Nanofat samples exhibited a cell yield of 6.63 million cells/g lipoaspirate, whereas stromal vascular fraction preparations resulted in only 0.68 million cells/g lipoaspirate. The final cell inoculum obtained from stromal vascular fraction isolation was 120 million cells and it required 200 to 250 cc of raw lipoaspirate as starting material, whereas nanofat preparation resulted in 125 million cells with only 20 cc of raw lipoaspirate. CONCLUSION: Mechanical disaggregation offers a better cell inoculum than conventional enzymatic dissociation methods by using 10 times less fat tissue as starting material and delivering a higher cell yield.

Reproducible Volume Restoration and Efficient Long-term Volume Retention after Point-of-care Standardized Cell-enhanced Fat Grafting in Breast Surgery.

UNLABELLED: Lipoaspirated fat grafts are used to reconstruct volume defects in breast surgery. Although intraoperative treatment decisions are influenced by volume changes observed immediately after grafting, clinical effect and patient satisfaction are dependent on volume retention over time. The study objectives were to determine how immediate breast volume changes correlate to implanted graft volumes, to understand long-term adipose graft volume changes, and to study the "dose" effect of adding autologous stromal vascular fraction (SVF) cells to fat grafts on long-term volume retention. METHODS: A total of 74 patients underwent 77 cell-enhanced fat grafting procedures to restore breast volume deficits associated with cosmetic and reconstructive indications. Although all procedures used standardized fat grafts, 21 of the fat grafts were enriched with a low dose of SVF cells and 56 were enriched with a high SVF cell dose. Three-dimensional imaging was used to quantify volume retention over time. RESULTS: For each milliliter of injected fat graft, immediate changes in breast volume were shown to be lower than the actual volume implanted for all methods and clinical indications treated. Long-term breast volume changes stabilize by 90-120 days after grafting. Final volume retention in the long-term was higher with high cell-enhanced fat grafts. CONCLUSIONS: Intraoperative immediate breast volume changes do not correspond with implanted fat graft volumes. In the early postoperative period (7-21 days), breast volume increases more than the implanted volume and then rapidly decreases in the subsequent 30-60 days. High-dose cell-enhanced fat grafts decrease early postsurgical breast edema and significantly improve long-term volume retention.