Biocompatibility of Subcutaneously Implanted Plant-Derived Cellulose Biomaterials

Abstract

There is intense interest in developing novel biomaterials which support the invasion and proliferation of living cells for potential applications in tissue engineering and regenerative medicine. Decellularization of existing tissues have formed the basis of one major approach to producing 3D scaffolds for such purposes. In this study, we utilize the native hypanthium tissue of apples and a simple preparation methodology to create implantable cellulose scaffolds. To examine biocompatibility, scaffolds were subcutaneously implanted in wild-type, immunocompetent mice (males and females; 6–9 weeks old). Following the implantation, the scaffolds were resected at 1, 4 and 8 weeks and processed for histological analysis (H&E, Masson’s Trichrome, anti-CD31 and anti-CD45 antibodies). Histological analysis revealed a characteristic foreign body response to the scaffold 1 week post-implantation. However, the immune response was observed to gradually disappear by 8 weeks post-implantation. By 8 weeks, there was no immune response in the surrounding dermis tissue and active fibroblast migration within the cellulose scaffold was observed. This was concomitant with the deposition of a new collagen extracellular matrix. Furthermore, active blood vessel formation within the scaffold was observed throughout the period of study indicating the pro-angiogenic properties of the native scaffolds. Finally, while the scaffolds retain much of their original shape they do undergo a slow deformation over the 8-week length of the study. Taken together, our results demonstrate that native cellulose scaffolds are biocompatible and exhibit promising potential as a surgical biomaterial.

Crossing kingdoms: Using decellularized plants as perfusable tissue engineering scaffolds

“…More recently, however, cellulose was isolated from decellularized apple hypanthium tissue and was used to support cellular attachment and proliferation in a 3D scaffold [22]. That material was found to be biocompatible when implanted subcutaneously in vivo [23]. Coupling the similarities seen between mammalian and plant vasculature with the apparent biocompatibility and regenerative properties of the plant tissue, we sought to cross kingdoms and study whether decellularized plants could serve as a perfusable scaffold for tissue engineering.…”

“…Decellularized cellulose is biocompatible and biodegradable [23], but it is unclear the in vivo response to whole decellularized plant tissue. Future investigation will need be made into the native immune response to more complex compositional plant scaffolds.…”

“…Cellulose is biocompatible and has been shown to promote wound healing [21]. Furthermore, cellulosic tissue engineering scaffolds derived from decellularized apple slices have shown the ability for mammalian cell attachment and proliferation [22] and were found to be biocompatible when implanted subcutaneously in vivo [23]. Pectin [24] and hemicellulose [25] have also been studied as biomaterials for bone tissue engineering and wound healing, respectively.…”

A novel surgical technique for a rat subcutaneous implantation of a tissue engineered scaffold

“…Although it is common to use different animals such as rabbits and mice for subcutaneous implantation; rat subcutaneous implants are one of the most studied because it enables the assessment of tissue compatibility such as possible sensitization, irritation, intracutanous reactivity, systemic toxicity, genotoxicity, implantation, chronic toxicity, carcinogenicity, biodegradation, and immune response (Modulevsky et al, 2016; Wang et al, 2017; Cunniffe et al, 2015; Ripamonti, 1996). Despite time and costs, it is crucial to have a reliable method for implantation.…”

“…Despite time and costs, it is crucial to have a reliable method for implantation. Subcutaneous implantation allows for the observation of an inflammatory response, cellularization of the extracellular matrix, and angiogenesis validation (Modulevsky et al, 2016; Guarnieri et al, 2014; Stapleton et al, 2010; Meagher et al, 2016; Mazza et al, 2015). …”