Joris van Dongen

149 The power of fat and ASCs for scar treatment: a review DEVELOPMENT OF LIPOFILLING PROCEDURES Transfer of adipose tissue, also known as fat grafting, lipografting or lipofilling is recognized as a promising and novel technique for correction of volume deficiency, skin rejuvenation and as treatment for scars. This is strongly supported by evidence- based clinical trials as well as fundamental studies in animals and in vitro . The first case of lipofilling in literature dates from 1893, when Gustav Neuber described the first free fat transfer for a scar which had left a young man with a soft tissue defect of the face 1 . As soon as liposuction was further developed in the mid 1980’s, also interest developed of re-using the lipoaspirated subcutaneous adipose tissue. Liposuction pioneers such as Illouz and co-workers 2 developed the first clinical applications and methods for lipofilling to restore or gain volume. The real breakthrough in lipofilling came with fat harvesting, subsequent processing and subcutaneous administration as described by Coleman 3 , which allowed better survival of the lipograft. Centrifugation was the first successful attempt to improve fat graft survival by removing oil, fluid and dead cells from the harvested fat tissue. This method also inspired clinical trials to assess volumetric augmentation of the breast and buttocks 4,5 . Initially, introduced by Coleman in the early nineties, the use of small liposuction and lipofilling cannulas also opened the door for lipofilling of the face and hands for both reconstructive and aesthetic purposes. Especially in these applications with rather superficial lipofilling, effects described as ‘more than volume alone’ were often observed 3,6 . This included an improved appearance and quality of the skin and has subsequently been described in many case reports. Yet a mechanistic underpinning was still lacking. These clinical observations initiated a wide range of clinical applications for lipofilling other than just volume adjustment 7 . This novel idea to use lipofilling for treatment of (the consequences of ) tissue damage, has led to the use of lipofilling to treat burn scars 8 and even to alleviate scar-associated pain as occurring e.g. after mastectomy 9 . In 2001, Zuk and colleagues 10 demonstrated that adipose tissue had a source of endogenous mesenchymal stem cells, which were named adipose-derived stem or stromal cells (ADSC). This discovery significantly advanced the use of lipofilling as a regenerative therapy, as it had been shown that at least one of the components of adipose tissue had therapeutic potential. Since then, many of the beneficial effects observed after lipofilling have been attributed to ADSC.