Stem Cell Enriched Fat Transfer

Abstract

Recently, medical techniques have been proposed for tissue regeneration using autologous adult fat stem cells obtained with liposuction to restore the regular volumes of adipose tissue in the body and especially in the face. The regeneration of the face adipose tissue follows the outline of a technique already in use: the lipofilling. This process is based on fat cells obtained with low-pressure suction and further centrifugation to separate fat cells from the stroma-vascular connective tissue.. The aim is to infiltrate only intact cells, able to survive in their new home [1]. For the technique of regeneration we basically do not use only normal fat cells but mainly fat stem cells. These are sown in small amounts to stimulate the formation of new adipose tissue (liposowing) [2] The fat is rich of stem cells [3]. An average rate of fat stem cells in adipose tissue is one of every 50 normal fat cells (compared to bone marrow that contains 1 for 10000). Today there is a huge discussion about the use of stem cells present in adipose tissue. [4] The large numbers of stem cells in adipose tissue means that clinically relevant stem cell numbers could be extracted from the tissue, potentially eliminating the need for in vitro expansion. To utilize these characteristics of adipose tissue fully, Cytori Therapeutics Inc. has developed a closed system called Celution to isolate and concentrate stem cells and regenerative cells automatically from adipose tissue. [5] J. Victor Garcia and Maurizio Ceccarelli have developed a simple technique to enrich stem cells in the area of collection for Liposowing. This technique has been presented for the first time at BioBridge Event of 2008 in Geneva Palais des Nations and you can find references about it on www.ijcs.org and on www.aephymed.org. [49] [2] The explanation of why fat is so rich in adult stem cells, can be sought in the biological function of this tissue: the energy storage. The adipocyte is able to significantly increase its volume to collect energy in the triglycerides form. [6] But when its volume is very high (higher than 170% of normal volume) the adipocyte stimulates the formation of new adipose tissue by activating the differentiation of stem cells in the stroma-vascular connective tissue. [7] The liposintetic stimulus leads to adipocyte hypertrophy that, at a certain volume, stimulates perivascular stem cell propagation and differentiation. The stimulus for preadipocytes mitosis and differentiation, follows mainly the increase of the insulin rate for the receptor down regulation and the liberation IGF-1 in the hypertrophic adipocyte. [8]