Isolation, Proliferation and Differentiation of Rhesus Macaque Adipose-Derived Stem Cells

Summary

In this article, we describe isolation of rhesus macaque derived adipose-derived stem cells (ADSCs) using an enzymatic tissue digestion protocol. Next, we describe ADSC proliferation which includes cell detachment, counting and plating. Lastly, ADSC differentiation is described using specific adipogenic inducing agents. Additionally, we describe staining techniques to confirm differentiation.

Abstract

Adipose tissue provides a rich and accessible source of multipotent stem cells, which are able to self-renew. These adipose-derived stem cells (ADSCs) provide a consistent ex vivo cellular system that are functionally like that of in vivo adipocytes. Use of ADSCs in biomedical research allows for cellular investigation of adipose tissue metabolic regulation and function. ADSC differentiation is necessary for adequate adipocyte expansion, and suboptimal differentiation is a major mechanism of adipose dysfunction. Understanding changes in ADSC differentiation is crucial to understanding the development of metabolic dysfunction and disease. The protocols described in this manuscript, when followed, will yield mature adipocytes that can be used for several in vitro functional tests to assess ADSC metabolic function, including but not limited to assays measuring glucose uptake, lipolysis, lipogenesis, and secretion. Rhesus macaques (Macaca mulatta) are physiologically, anatomically, and evolutionarily similar to humans and as such, their tissues and cells have been used extensively in biomedical research and for development of treatments. Here, we describe ADSC isolation using fresh subcutaneous and omental adipose tissue obtained from 4–9-year old rhesus macaques. Adipose tissue samples are enzymatically digested in collagenase followed by filtration and centrifugation to isolate ADSCs from the stromal vascular fraction. Isolated ADSCs are proliferated in stromal media followed by approximately 14–21 days of differentiation using a cocktail of 0.5 μg/mL dexamethasone, 0.5 mM isobutyl methylxanthine, and 50 μM indomethacin in stromal media. Mature adipocytes are observed at approximately 14 days of differentiation. In this manuscript, we describe protocols for ADSC isolation, proliferation, and differentiation in vitro. Although, we have focused on ADSCs from rhesus macaque adipose tissue, these protocols can be utilized for adipose tissue obtained from other animals with minimal adjustments.

Introduction

Adipose tissue is comprised of a heterogeneous mixture of cells, predominantly mature adipocytes and a stromal vascular fraction including fibroblasts, immune cells and adipose-derived stem cells (ADSCs)^1,2,3. Primary ADSCs can be isolated directly from white adipose tissue and stimulated to differentiate into adipocytes, cartilage or bone cells⁴. ADSCs exhibit classical stem cell characteristics such as maintenance of multipotency in vitro and self-renewal; and are adherent to plastic in culture^5,6<....

Protocol

All obtained tissues and procedures were approved by the Institutional Animal Care and Use Committee at the Louisiana State University Health Sciences Center and were performed in accordance with the guidelines of the National Institute of Health (NIH publication No. 85-12, revised 1996).

1. Preparation of buffers and solutions

1. Prepare sterile 5-phosphate-buffered saline wash buffer (5-PBS) solution by adding 5% penicillin/streptomycin (pen/strep) and 0.25 μg/mL of fungal inhibitor to 1x PBS. Prepare sterile 2-PBS wash buffer (2-PBS) solution by adding 2% pen/strep and 0.25 μg/mL of fungal inhibitor in 1x PBS. Wash buf....

Results

The ADSCs isolated from rhesus macaque adipose tissue samples were seeded on culture plates and is shown in Figure 1. On the day of plating, cells are non-adherent and float in the culture dish as shown in Figure 1A. Within 72 h, ADSCs will become 80% confluent and are ready for adipocyte differentiation (Figure 1B). ADSCs exhibit strong adipogenic characteristics after chemical induction. After 14 days of differentiation, mature ad.......

Discussion

ADSC isolation, proliferation and differentiation protocols are straight-forward and reproducible, but they require careful technique to ensure adequate isolation, healthy expansion, and efficient differentiation. A sterile working environment is critical for all cell culture experiments. Bacteria or fungi may be introduced into cell cultures through contaminated tools, media or work environment. Fungal contamination is indicated by spore growth in the culture, while bacterial contamination is indicated by the presence o.......

Materials

Name	Company	Catalog Number	Comments
0.4 % trypan blue	Thermo-Fisher	15250061
1.5-ml microcentrifuge tube	Dot Scientific	707-FTG
100 % isopropanol	Sigma-Aldrich	PX1838-P
100-mm cell culture dish	Corning	430167
3-Isobutyl-1-methylxanthine	Sigma-Aldrich	I7018
50-mL plastic conical tube	Fisher Scientific	50-465-232
70-µm cell strainer	Corning	CLS431751
a-MEM	Thermo-Fisher	12561056
Aluminum foil	Reynolds Wrap
BODIPY	Thermo-Fisher	D3922
Bovine serum albumin (BSA)	Sigma-Aldrich	05470
Centrifuge	Eppendorf	5810 R
Collagenase, Type I	Thermo-Fisher	17100017
Dexamethasone-Water Soluble	Sigma-Aldrich	D2915
Dimethyl sulfoxide, DMSO	Sigma-Aldrich	D2650
Distilled water	Thermo-Fisher	15230162
Fetal Bovine Serum, USDA-approved	Sigma-Aldrich	F0926
Fungizone/Amphotericin B (250 ug/mL)	Thermo-Fisher	15290018
Hanks' Balanced Salt Solution (HBSS)	Thermo-Fisher	14175095
Hemacytometer with cover slip	Sigma-Aldrich	Z359629
Indomethacin	Sigma-Aldrich	I7378
Inverted light microscope	Nikon	DIAPHOT-TMD
L-glutamine (200 mM)	Thermo-Fisher	25030081
Laboratory rocker, 0.5 to 1.0 Hz	Reliable Scientific	Model 55 Rocking
Neutral buffered formalin (10 %)	Pharmco	8BUFF-FORM
Oil Red O	Sigma-Aldrich	O0625
Paraformeldehyde	Sigma-Aldrich	P6148
Penicillin-Streptomycin (10,000 U/mL)	Thermo-Fisher	15140122
Phosphate buffered saline (PBS), pH 7.4	Thermo-Fisher	10010023
Red blood cell (RBC) lysis buffer	Qiagen	158904
Serological pipettes, 2 to 25 mL	Costar Stripettes
Standard humidified cell culture incubator, 37 °C, 5 % CO2	Sanyo	MCO-17AIC
Trypsin-EDTA (0.25%)	Thermo-Fisher	25200056