Impact of the Different Preparation Methods to Obtain Human Adipose-Derived Stromal Vascular Fraction Cells (AD-SVFs) and Human Adipose-Derived Mesenchymal Stem Cells (AD-MSCs): Enzymatic Digestion Versus Mechanical Centrifugation

Abstract

Autologous therapies using adipose-derived stromal vascular fraction (AD-SVFs) and adult adipose-derived mesenchymal stem cells (AD-MSCs) warrant careful preparation of the harvested adipose tissue. Currently, no standardized technique for this preparation exists. Processing quantitative standards (PQSs) define manufacturing quantitative variables (such as time, volume, and pressure). Processing qualitative standards (PQLSs) define the quality of the materials and methods in manufacturing. The purpose of the review was to use PQSs and PQLSs to report the in vivo and in vitro results obtained by different processing kits that use different procedures (enzymatic vs. non-enzymatic) to isolate human AD-SVFs/AD-MSCs. PQSs included the volume of fat tissue harvested and reagents used, the time/gravity of centrifugation, and the time, temperature, and tilt level/speed of incubation and/or centrifugation. PQLSs included the use of a collagenase, a processing time of 30 min, kit weight, transparency of the kit components, the maintenance of a closed sterile processing environment, and the use of a small centrifuge and incubating rocker. Using a kit with the PQSs and PQLSs described in this study enables the isolation of AD-MSCs that meet the consensus quality criteria. As the discovery of new critical quality attributes (CQAs) of AD-MSCs evolve with respect to purity and potency, adjustments to these benchmark PQSs and PQLs will hopefully isolate AD-MSCs of various CQAs with greater reproducibility, quality, and safety. Confirmatory studies will no doubt need to be completed.

Adipose-derived stromal stem cells (ASCs) as a new regenerative immediate therapy combating coronavirus (COVID-19)-induced pneumonia

“…It is possible to report many different fields of human MSCs application as in the immune-mediated inflammatory diseases (graft-versus-host disease and systemic lupus erythematosus) [27,28] and also in lower extremity ulcers [29], calvarial defects [30], craniofacial microsomia [31], breast reconstruction [32][33][34][35][36][37][38], outcomes of burns and scars [39]. These ASCs can be further isolated using minimal manipulation based on mechanical filtration and centrifugation or using enzymatic digestion as previously published many times [21,[34][35][36][37][38][39], and in particular, as described recently [40].…”

“…Both for autologous that allogeneic use, the ASCs and the SVFs in which they are contained (1 mL of fat tissue offers 100.000 SVFs of which 1%-3% are ASCs = 1.000/3.000), can be harvested by 100 mL of fat tissue, obtained by a very simple, fast, and safe gently liposuction, performed also in local anesthesia, from the abdomen, flank, and thigh regions [5,[34][35][36]39]. The 100 mL of fat may be processed via three different possibilities as previously published many times [5,[34][35][36]39,40]:…”

“…(1) The minimal manipulation is based on mechanical centrifugation and filtration of adipose tissue harvested with liposuction [35,39,40]. (2) The enzymatic digestion is based on the use of human collagenase [21,34,36,40] and may be divided into two types (automatic and manual).…”

“…(1) The minimal manipulation is based on mechanical centrifugation and filtration of adipose tissue harvested with liposuction [35,39,40]. (2) The enzymatic digestion is based on the use of human collagenase [21,34,36,40] and may be divided into two types (automatic and manual). Automatic enzymatic digestion can be performed by a closed specific machine, using human trypsin as collagenases, while manual enzymatic digestion would be performed by an expert biologist in this field during the surgical procedure [21,34,36,40].…”

“…Additionally, it is possible to involve a biologist expert in this field of fat digestion when manual enzymatic digestion is required. All these procedures of fat tissue manipulation, aimed to obtain an SVFs pellet containing ASCs, are regulated by the European rules (1394/2007 EC) and EMA/CAT recommendations (20 June 2014 EMA/CAT/600,280/2010 Rev 1) [21,[34][35][36]39,40].…”