The Combination of Mechanically Isolated Stromal Vascular Fraction and Fibrin Hydrogel: A Processing Protocol

Summary

Mechanically isolated stromal vascular fraction (SVF) in combination with a fibrin hydrogel offers an easy and efficient carrier for viable adipose-derived stromal cells for various indications, including tissue engineering and or wound healing purposes. Here, we present the preparation of a mechanical SVF (mSVF)-fibrin hydrogel construct for translational research and clinical application.

Abstract

The regenerative potential of adipose-derived stromal cells (ASCs) has gained significant attention in regenerative and translational research. In the past, the extraction of these cells from adipose tissue required a multistep enzyme-based process, resulting in a heterogenous cell mix consisting of ACSs and other cells, which are jointly termed the stromal vascular fraction (SVF). More recently introduced mechanical SVF (mSVF) isolation protocols are less time-consuming and bypass regulatory concerns. We recently proposed a protocol that generates mSVF rich in stromal cells based on a combination of emulsification and centrifugation. One current issue in mSVF application for wound therapy application is the lack of a scaffold providing protection from mechanical manipulation and desiccation. Fibrin hydrogels have been shown to be a useful adjunct in cell transfer for wound healing purposes in the past. In the work herein, we delineate the preparation steps of an mSVF-fibrin hydrogel construct as a novel approach for translational research and clinical application.

Introduction

Over the past few years, regenerative plastic surgery has emerged as an additional pillar of plastic surgery¹. Regenerative plastic surgery aims to restore damaged tissue by transferring soluble factors, cells, and tissue harvested from the patient to promote tissue restoration in a minimally invasive manner². Adipose-derived stem cells (ASCs) have gained attention due to their ability to differentiate into multiple mesenchymal lineages, making them a promising candidate for regenerative medicine research³. Their cytokine profile displays angiogenic, immunosuppressive, and an....

Protocol

This study was performed in accordance with the Declaration of Helsinki. All adult donors provided written informed consent to allow further use of the collected tissue samples. The protocol follows the guidelines of our institution's human research ethics committee.

1. Harvest of adipose tissue

1. Harvest the adipose tissue by performing a standard liposuction in a conventional fat-harvesting technique described in previous publications²⁶<.......

Discussion

The mechanical isolation of SVF provides an elegant alternative to the traditional enzymatic approach and offers broad access for clinical application²⁹. In fact, mSVF, as proposed in the present manuscript, is already in clinical use for soft tissue treatment of scars or as an adjunct for cosmetic procedures³⁰. The protocol presented here provides a simple method for efficient topical delivery of viable mSVF cells. While the positive control with only mSVF cells showed a t.......

Materials

Name	Company	Catalog Number	Comments
12-Wellplate	Sarstedt	83.3921
4′,6-diamidino-2-phenylindole (DAPI)	Biochemica	A1001.0010
50 mL-Falcon	Falcon	352070
Absorbent Towels, Two Pack	Halyard	89701
Alamar blue 25 mL	Invitrogen	DAL1025
Albumin, Bovine (BSA)	VWR	0332-500G
Biotek Cytation 5	Agilent		Cell Imaging Multimode Microplate Reader
CaCl2	Sigma-Aldrich	C5670-500G
Cryostat	Microtome
DMEM with 4,5 g/L glucose,with L-Glutamine, with sodium pyruvate	VWR	392-0416
DPBS	Gibco	14190-144
Epinephrin	Sigma-Aldrich	E4250
Fetal Bovine Serum	Biowest	S181H-500
Fibrinogen Human Plasma 100 mg	Sigma-Aldrich	341576-100MG
Formalin	Fisher Scientific	SF100-4
Formalin 4%	Formafix	1308069
FSC 22-Einbettmedium, blau	Biosystems	3801481S
Hematoxylin & Eosin Solution	Sigma-Aldrich	H3136 / HT110132
Lactated Ringer’s Solution 1000 mL	B Braun	R5410-01
Mercedes Cannula 4mm	MicroAire	PAL-R404LL
NaCl 0.9%	Bbraun	570160
OCT Embedding Matrix 125 mL	CellPath	KMA-0100-00A
Paraformaldehyde	Fisher Scientific	10342243
PBS 1%	Sigma-Aldrich	P4474
PenStrep	Sigma-Aldrich	P4333-100ML
Petridish 150mm	Sarstedt	83.1803
Phalloidin-iFluor 488 Reagent	Abcam	ab176753
Sterile Syringe 20 mL Luer	HENKE-JECT	5200-000V0
Sterile Syringe 30 mL Luer-Lock	BD	10521
Thrombin from Human Plasma	Sigma-Aldrich	T6884-100UN
Tranexamic acid	Orpha Swiss	6837093
Tulipfilter 1.2	Lencion Surgical	ATLLLL
Tulipfilter 1.4	Lencion Surgical	ATLLLL