Adipose Component Transplantation: An Advanced Fat-Grafting Strategy for Facial Rejuvenation.

BACKGROUND: Autologous fat grafting is frequently used for volume augmentation and tissue regeneration. The uniform physical and biological characteristics of fat grafts, however, limit their optimal effects in various situations. Subjecting fat tissue to different mechanical processes results in adipose-derived products with distinct biological components and physical features. The present study describes a novel facial fat-grafting strategy, adipose component transplantation (ACT), that yields different adipose products that can be applied to specific injection sites. METHODS: All patients who underwent ACT were evaluated retrospectively. Fat tissue samples were fractionated into high-density fat, adipose matrix complex, stromal vascular fraction gel, and adipose collagen fragment, as described. Each of these fractions was processed and injected into indicated recipient sites. Additional SVF gel was cryopreserved and, if necessary, injected during the following 3 months. Patients were followed up after 1, 2, 3, and 6 months, and annually thereafter. RESULTS: From March of 2020 to September of 2021, 78 patients underwent whole face fat grafting using the ACT strategy. All operations and secondary injections of cryopreserved SVF gel were uneventful. There were no major complications, and final aesthetic results were satisfactory in 91% of patients. CONCLUSIONS: The ACT strategy allows specific adipose products to be applied to specific injection sites, as warranted. Adipose matrix complex is indicated for sufficient rigid support, high-density fat when large volumes are required, SVF gel for precise injection and cryopreservation, and ACF as mesotherapy for skin rejuvenation. The ACT strategy optimizes the biological functions and physical features of different adipose-derived products. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Long-acting microneedle patch loaded with adipose collagen fragment for preventing the skin photoaging in mice.

Skin photoaging is one of the most serious public health problems in the 21st century that may lead to thin, saggy, and structurally weakened skin. Adipokine therapy toward skin photoaging is always associated with poor permeability, biologic stability and the short in vivo release duration. Our laboratory previously extracted an extracellular matrix component of adipose tissue by purely physical methods, namely "adipose collagen fragment (ACF)", which holds promise for preventing skin photoaging. However, the injection treatment of ACF requires repeated preparation processes and injection procedures, which may be time-consuming and painful. Therefore, we describe the fabrication and assessment of a detachable ACF-microneedle (ACF-MN) patch that creates minimally invasive dermal microtrauma upon application. And we evaluated the morphology characterization, mechanical properties and puncture performance in vitro. The delivery efficiency of ACF from the patches was estimated in vitro and vivo. Then, the therapeutic efficacy was identified through applying ACF-MN patches into the dermis of UVA-induced photoaging mice and the related detection of skin photoaging was estimated. Our results demonstrated that ACF-MN exhibited well skin puncture performance and could release ACF component slowly. Meanwhile, this microneedle device loaded with ACF exhibited the treatment efficiency on skin photoaging in a mouse model. Therefore, implantation of the microtrauma-mediated, long-acting ACF-MN system can be utilized as a potential candidate for preventing skin photoaging in the clinic.

Biocompatible Interface-Modified Tissue Engineering Chamber Reduces Capsular Contracture and Enlarges Regenerated Adipose Tissue.

Adipose flap expansion using a tissue engineering chamber (TEC) presents a promising candidate for soft tissue regeneration by activating in situ adipose tissue regeneration. However, foreign body reaction (FBR) and capsular contracture caused by a silicone chamber limit large tissue reconstruction. Here, a hydrophilic and biodegradable film made of poly(ethylene glycol) diacrylate (PEG-da) with methacrylated gelatin (gelatin-MA) was presented between the host tissue and silicone chamber to tune the local wound and to prevent initiation of FBR. After a 60 day investigation, 6.1-fold-regenerated fat tissue was obtained from the PEG-gelatin group, whereas only 3-fold tissue was harvested from a silicone group. Histological staining demonstrated that the structure of the neo-formed adipose tissue in both groups was similar to mature adipose tissue. Noticeably, a more distinct and denser fibrous capsule was observed in the silicone group compared to the PEG-gelatin group. Immunohistochemistry of CD206 and TGF-ß expression indicated less M2 macrophage infiltration and a minor inflammation reaction with PEG-gelatin assistance. Less collagen deposition and myofibroblast activation in the PEG-gelatin group were demonstrated via α-SMA and type I collagen staining. All these demonstrated that a biocompatible membrane supplement can attenuate capsule formation and contracture leading to a larger tissue regeneration through the TEC technique, which could lead to new perspectives to the relationship between materials-mattered FBR and tissue regeneration.