Two Methods for Decellularization of Plant Tissues for Tissue Engineering Applications

Summary

Here we present, and contrast two protocols used to decellularize plant tissues: a detergent-based approach and a detergent-free approach. Both methods leave behind the extracellular matrix of the plant tissues used, which can then be utilized as scaffolds for tissue engineering applications.

Abstract

The autologous, synthetic, and animal-derived grafts currently used as scaffolds for tissue replacement have limitations due to low availability, poor biocompatibility, and cost. Plant tissues have favorable characteristics that make them uniquely suited for use as scaffolds, such as high surface area, excellent water transport and retention, interconnected porosity, preexisting vascular networks, and a wide range of mechanical properties. Two successful methods of plant decellularization for tissue engineering applications are described here. The first method is based on detergent baths to remove cellular matter, which is similar to previously established methods used to clear mammalian tissues. The second is a detergent-free method adapted from a protocol that isolates leaf vasculature and involves the use of a heated bleach and salt bath to clear the leaves and stems. Both methods yield scaffolds with comparable mechanical properties and low cellular metabolic impact, thus allowing the user to select the protocol which better suits their intended application.

Introduction

Tissue engineering emerged in the 1980s to create living tissue substitutes, and potentially address significant organ and tissue shortages¹. One strategy has used scaffolds to stimulate and guide the body to regenerate missing tissues or organs. Although advanced manufacturing approaches such as 3-D printing have produced scaffolds with unique physical properties, the ability to manufacture scaffolds with a diverse range of achievable physical and biological properties remains a challenge^2,3. Moreover, due to a lack of a functional vascular network, these techniques have been limited i....

Protocol

1. Decellularization of Plant Tissue Using the Detergent-based Approach

1. Use fresh or frozen F. hispida, leaf samples. Freeze unused fresh samples in a -20 °C freezer and store for future use (up to a year).
   NOTE: Use stem or leaf tissue of nearly any desired plant. Extended storage times can cause damage to the tissues.
   1. Determine the size and shape of samples to be processed on the basis of the sample’s intended use (i.e. samples cut into strips are well suited for mechanical testing applications, meanwhile 8 mm disc samples are useful in multi-well culturing applications). Cut the leaf into ....

Results

Both methods yielded scaffolds that were suitable for cell culture and tissue engineering applications. Figure 1 shows the general workflow of the decellularization process using an intact leaf for the detergent-based method and cut samples (8 mm diameter) for the detergent-free method. Successful decellularization of Ficus hispida tissues following both methods yielded clear and intact samples (Figure 1A and 1B<.......

Discussion

Herein, two methods to decellularize plant tissues are described. The results presented here, coupled with the results of prior studies²⁵, suggest that the protocols put forth are likely applicable to a wide spectrum of plant species and can be performed on both stems and leaves. These procedures are simple and do not require specialized equipment, so plant decellularization can be carried out in most laboratories. It is noteworthy that after decellularization, the scaffolds must be functionalized.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Sodium dodecyl sulfate	Sigma Life Science	75746-1KG
Triton X-100	MP Biomedicals, LLC	807426	Non-ionic surfactant referenced in paper. Very viscous reagent, can help to cut end of pipette tip when drawing it up.
Concentrated bleach (8.25% sodium hypochlorite)	Clorox	Item #: 31009	Standard concentrated bleach.
Sodium bicarbonate	Acros Organics	217120010	Can be substituted with sodium hydroxide or sodium carbonate.
8 mm Biopunch	HealthLink	15111-80	Cuts samples that fit well in 24 well plate
Belly Dancer-Shake table	Stovall Life Sciences	BDRAA115S	Use low speeds to not damage tissues. Can use any model/brand of shake table.
Isotemp hot/stir plate	Fisher Scientific		Can use any style/brand of hot/stir plate.
Beaker	Any		Can use any size beaker as long as it will fit your samples and not overcrowd them.
Tris Hydrochloride	Fisher Scientific	BP153-500
DMEM	Corning	MT50003PC
Quant-iT Picogreen dsDNA assay	Life Technologies	P11496	Can use any dsDNA quantification mehtod on hand.