Lipotransfer (Fat Grafting) (Fat Transfer)
What is Fat Transfer?
Fat grafting, fat transfer, alos referred fat injections, is the surgical process by which the movement of fat cells (adipocytes) from one part of the body (the donor area) to another (the recipient area). The surgical goal is to improve or augment the area where the fat is injected.
The technique of grafting a tissue involves removing it by liposuction from its blood supply entirely, then processing the fat, & then re-injecting purified fat into the area needing improvement relying on the in-growth of a new capillary network to support the transferred cells once they are at the recipient site. It is the establishment of this new blood supply that is crucial to the survival of the transferred tissue. If this fails, it will result in graft loss; in the case of adipocytes, necrosis of the cells, with resorption of their lipid content (and loss of volume at the recipient site). As the capillaries in-growth takes a few days following graft placement, the fat cells to survive must rely on diffusion of nourishes to the block of tissue from surrounding recipient tissue. If the fat particles are very small and have a large surface-to-volume ratio (microlipofilling technique) then, the whole particle will survive. Large particle size, mean inner surface will not achieve re-establishment of blood flow in time to prevent cellular death. Therefore, small particle grafting (micro-lipofilling) is essential and will have better rate of graft take.
Since the 1990’s Plastic Surgeons have reliably used fat grafting as a way to improve & enhance the cosmetic appearance of the face, breast, hands, feet, hips, and buttocks. However, more recently, clinicians have documented the therapeutic benefits of fat grafting in the healing of wounds and scars, as well as fat’s ability to repair damage to breast tissue following radiation treatment.
History of Fat Transfer & ADSCs
- The first ‘fat grafting’ procedure dates back to the late 19th century, 1893, when a German Plastic Surgeon, Gustav Neuber (1850-1932) transferred fat from the arm to the orbital (eye) region to correct scars formed from osteomyelitis (bone infection).
Only two years later, 1895, Dr. Viktor Czerny (1842-1916) transferred a lipoma to the breast to establish symmetry following a unilateral partial mastectomy.
The the first reports of fat injection to the face & breast in the human body to re-established contour deformities was carried out by Eugene Hollander in 1909
- In the 1950s, because of its tendency to reabsorb and form oily cysts, fat grafting to the face fell from favour, becoming an almost obsolete procedure.
- With the advent of liposuction, fat injection was rediscovered, but the reabsorption rate was still high.
- In the 1990s, Sydney Colman systematized the technique for harvesting, purification, and placement of fat, so as to reduce the resorption rate.
- In 2001, Zuk & colleagues demonstrated that adipose tissue is the greatest source of adult mesenchymal stem cells, adipose-derived stem cells, capable of differentiating into other types of tissues.
- Stromal vascular fraction (SVF), a source of ADSCs, endothelial (progenitor) cells, T cells, B cells, mast cells, and adipose tissue macrophages was identified.
- In 2007, Gino Rigotti (Italy) applied the regenerative properties of ADSCs in a human patient. He successfully managed radiation tissue damages, with complete restitution of the affected tissues. This was one of the first example of regenerative therapies.
Development of Lipofilling Procedures
Transfer of adipose tissue or lipofilling, is recognized as a promising & 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 & humans. The first case of fat transfer in literature dates from 1893. As soon as liposuction was further developed in the mid-1980s, also interest developed of re-using the lipoaspirated subcutaneous adipose tissue. Liposuction pioneers such as Illouz and co-workers (Illouz,1983) developed the first clinical applications and methods for lipofilling to restore or gain volume. The real break-through in lipofilling came with fat harvesting, subsequent processing and subcutaneous administration as described by Coleman (2002), which allowed better survival of the fat transfer.
In the 1990’s, Dr. Sydney Coleman, a New York City Plastic Surgeon, began publishing papers describing standardized techniques for fat extraction, processing, and injection. Since that point in time, the procedure’s popularity has only increased along with a wider variety of clinical applications.He 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 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 (fat transfer), other than just volume adjustment Rigotti et al., (2007). This novel idea to use lipofilling for treatment of fibrosis result from tissue damage has led to the use of lipofilling to treat burn scars (Klinger et al., 2008) and even to alleviate scar-associated pain as occurring for example after mastectomy Caviggioli et al., (2011).
Zuk et al., (2001) demonstrated that adipose tissue had a source of endogenous mesenchymal stem cells (MSC), 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.
Battle Against Fat Reabsorption
The grafted fatty tissue is placed under ischaemia (low oxygen with low nutrition) & is temporarily nourished only by plasmatic diffusion from the surrounding host tissue for a few days until direct capillary supply is formed. Adipocytes, known to be very sensitive to hypoxia, can die within 24 hours. ADSCs are likely to be as resistant to ischemia up to 72 hours under severe ischemia Early cell death likely results in volume loss and histologic fibrosis and cyst formation. Model of fat graft behavior following implantation have defined three zones, with a peripheral, regenerating zone, and intermediate, inflammatory zone, and a central, necrotic zone. Diffusion of nutrients to the central zone is insufficient, resulting in necrosis & ultimate graft resorption.
In response to injury & cell death, many growth factors & proteinases are released from damaged tissue & activated platelets. Inflammatory cells are infiltrated & inflammatory cytokines such as interleukins are secreted.
Adipose grafting induces injury in the recipient tissue; bleeding from the host tissue activates platelets, which release various soluble factors activating sleeping stem cells. At the same time transplanted adipose tissue is temporarily placed under severe ischaemia; factors released from injured donor site & one released from dying cells stimulates adipose-derived stem cells (ADSCs) to release hepatocyte growth factor HGF, which promote angiogenesis and inhibits fibrogenesis. Most of the differentiated cells in graft die, but graft-resident stem cells are activated. the dead cells are partly replaced with next generation.
Read More & References:
- Carmen GY, Victor SM. 2006; Signalling mechanisms regulating lipolysis. Cell Signal 18(4): 401–408. Click Here for PDF
- Cawthorn WP, Scheller EL, MacDougald OA. 2012; Adipose tissue stem cells meet preadipocyte commitment: going back to the future. J Lipid Res 53(2): 227–246. Click Here for PDF
- Crisan M, Yap S, Casteilla L et al. 2008; A perivascular origin for mesenchymal stem cells in multiple human organs. Cell Stem Cell 3(3): 301–313. Click Here for PDF
- Dong Z, Peng Z, Chang Q, Lu F. 2013; The survival condition and immunoregulatory function of adipose stromal vascular fraction (SVF) in the early stage of non-vascularized adipose transplantation. PLoS One 8(11): e80364. Click Here for PDF
- Eto H, Kato H, Suga H et al. 2012; The fate of adipocytes after non-vascularized fat grafting: evidence of early death and replacement of adipocytes. Plast Reconstr Surg 129(5): 1081–1092. Click Here for PDF
- Eto H, Suga H, Matsumoto D et al. 2009; Characterization of structure and cellular components of aspirated and excised adipose tissue. Plast Reconstr Surg 124(4): 1087–1097. Click Here for PDF
- Fisher C, Grahovac TL, Schafer ME, Shippert RD, Marra KG, Rubin JP. 2013; Comparison of harvest and processing techniques for fat grafting and adipose stem cell isolation. Plast Reconstr Surg 132(2): 351–361. Click Here for PDF
- Hivernaud V, Lefourn B, Guicheux J et al. 2015; Autologous fat grafting in the breast: critical points and technique improvements. Aesthetic Plast Surg 39(4): 547–561. Click Here for PDF
- Ibatici A, Caviggioli F, Valeriano Vet al. 2014; Comparison of cell number, viability, phenotypic profile, clonogenic, and proliferative potential of adipose-derived stem cell populations between centrifuged and non-centrifuged fat. Aesthetic Plast Surg 38(5): 985–993. Click Here for PDF
- Kato H, Mineda K, Eto H et al. 2014; Degeneration, regeneration, and cicatrisation after fat grafting: dynamic total tissue remodelling during the first 3 months. Plast Reconstr Surg 133(3): 303e–313e. Click Here for PDF
- Lin G, Garcia M, Ning H et al. 2008; Defining stem and progenitor cells within adipose tissue. Stem Cells Dev 17(6):1053–1063. Click Here for PDF
- Mahoney, C. M., et al. (2018). “Current Therapeutic Strategies for Adipose Tissue Defects/Repair Using Engineered Biomaterials and Biomolecule Formulations.” Frontiers in Pharmacology 9(507).
- Pu LL, Coleman SR, Cui X, Ferguson Jr RE, Vasconez HC. 2008; Autologous fat grafts harvested and refined by the Coleman technique: a comparative study. Plast Reconstr Surg 122(3): 932–937. Click Here for PDF
- Suga H, Eto H, Aoi N et al. 2010; Adipose tissue remodelling under ischemia: death of adipocytes and activation of stem/progenitor cells. Plast Reconstr Surg 126(6):1911–1923. Click Here for PDF
- Tang W, Zeve D, Suh JM et al. 2008; White fat progenitor cells reside in the adipose vasculature. Science 322(5901): 583–586. Click Here for PDF
- Traktuev DO, Merfeld-Clauss S, Li J et al. 2008; A population of multipotent CD34-positive adipose stromal cells share pericyte and mesenchymal surface markers, reside in a peri endothelial location, and stabilize endothelial networks. Circ Res 102(1): 77–85. Click Here for PDF
- Tuin AJ, Domerchie PN, Schepers RH et al. 2016; What is the current optimal fat grafting processing technique? A systematic review. J Cranio-maxillofac Surg 44(1): 45–55.Click Here for PDF