Stem Cell-Based Soft Tissue Grafts for Plastic and Reconstructive Surgeries

Abstract

Adipose tissue is often a key structure to restore in reconstructive and augmentative surgeries. Current materials for soft tissue reconstruction or augmentation suffer from shortcomings such as suboptimal volume retention, donor site morbidity, and poor biocompatibility. A series of experiments are presented here to describe our stem cell-based approach to engineering human adipose tissue with predefined shape and dimensions. These findings indicate the real possibility that biologically viable adipose tissue can be engineered by taking a teaspoon full of tissue fluid containing the patient's adult stem cells, expanding them, differentiating them into adipogenic cells, and encapsulating them into appropriate biocompatible polymer materials. The end result is anticipated to be minimal donor site trauma related to needle size, immune compatibility because the patient's own stem cells are used, and long-term volume maintenance because stem cells are capable of replenishing adipogenic cells to retain the predefined shape and dimensions of the engineered soft tissue. Upcoming challenges include long-term volume maintenance, tissue maturation, angiogenesis, scaling up, and host tissue integration. Conceptually, stem cell-derived soft tissue grafts are realizable in plastic and reconstructive surgical procedures.

Vascularized Adipose Tissue Grafts from Human Mesenchymal Stem Cells with Bioactive Cues and Microchannel Conduits

“…PEG hydrogel lacking both microchannels and bFGF showed no host tissue infiltration (data not shown), consistent with our previous reports showing a lack of host tissue infiltration into PEG hydrogel. 41,43,44 Given that no cells are delivered in PEG hydrogel with or without bFGF and/or microchannels in this experiment, any and all infiltrating tissue into PEG hydrogel must be host derived. Figure 2, over the observed 35 days in ex vivo culture.…”

Continuing differentiation of human mesenchymal stem cells and induced chondrogenic and osteogenic lineages in electrospun PLGA nanofiber scaffold

“…Engineered tissue phenotypes from MSCs include osteochondral grafts with both cartilage and bone [3,[5][6][7][8][9][10], adipose tissue [11,12], tendon and ligaments [13][14][15] and skeletal muscle [5]. Despite the pioneering effort on the use of MSCs in the engineering of several tissue phenotypes, the optimal scaffolds that are capable of influencing and accommodating the growth and differentiation of MSCs are yet to be identified and likely are specific for each application.…”

Materials-Directed Differentiation of Mesenchymal Stem Cells for Tissue Engineering and Regeneration

“…Like many other tissue repair strategies, autologous tissue grafts are the preferred tissue source for this application. 114 However, soft tissue or fat grafts suffer from erratic graft resorption in reconstructive surgery, occurring in up to 80% of patients, and loss of filler architecture over time in elective plastic surgery 114-115 . Injectable soft tissue fillers including collagen, HA, HAP, and PLLA are effective to restore tissue volume but exhibit only temporary effects.…”