Human Recombinant Type I Collagen Produced in Plants

Abstract

As a central element of the extracellular matrix, collagen is intimately involved in tissue development, remodeling, and repair and confers high tensile strength to tissues. Numerous medical applications, particularly, wound healing, cell therapy, bone reconstruction, and cosmetic technologies, rely on its supportive and healing qualities. Its synthesis and assembly require a multitude of genes and post-translational modifications, where even minor deviations can be deleterious or even fatal. Historically, collagen was always extracted from animal and human cadaver sources, but bare risk of contamination and allergenicity and was subjected to harsh purification conditions resulting in irreversible modifications impeding its biofunctionality. In parallel, the highly complex and stringent post-translational processing of collagen, prerequisite of its viability and proper functioning, sets significant limitations on recombinant expression systems. A tobacco plant expression platform has been recruited to effectively express human collagen, along with three modifying enzymes, critical to collagen maturation. The plant extracted recombinant human collagen type I forms thermally stable helical structures, fibrillates, and demonstrates bioactivity resembling that of native collagen. Deployment of the highly versatile plant-based biofactory can be leveraged toward mass, rapid, and low-cost production of a wide variety of recombinant proteins. As in the case of collagen, proper planning can bypass plant-related limitations, to yield products structurally and functionally identical to their native counterparts.

Preparation and characterization of monomers to tetramers of a collagen-like domain fromStreptococcus pyogenes

“…7 However, the yields obtained may not be sufficient for widespread commercial use, although recent production of mammalian collagens in plants looks more promising as a commercial production direction. 8 More recently, the collagen like (CL) domain Scl2 from Streptococcus pyogenes has been proposed as a potential biomedical material 9 that is non-cytotoxic and non-immunogenic. 10 This protein can be readily prepared in good yields, up to around 19 g/L in 2 L fermentation studies 11 and can be purified using a simple precipitation and proteolysis approach.…”

Measuring the Osmotic Water Permeability Coefficient (P_f) of Spherical Cells: Isolated Plant Protoplasts as an Example

“…It is worthwhile to check whether this system is a viable alternative to oocytes for assaying AQPs even from animal sources (that functional animal proteins can be expressed in plant cells has been already demonstrated 17 ).…”

Bioengineered collagens

“…Notable progress has been made on commercial, recombinant production of human collagens. 7,[10][11][12][13][14][15][16][17] However, the rapidly emerging technologies that have characterized and produced recombinant non-animal (bacterial) collagens in E. coli [23][24][25]27,28 have introduced an exciting new collagen option that can be readily customized for specific biomedical applications. 28,33 These customized collagens will pave the way for more diverse applications in medical devices, implantable materials and potentially as scaffolds for stem cells, to name but a few examples of uses for these recombinant bacterial collagens.…”

“…Most recently, heterotrimeric collagen has been produced with P4H also present, giving excellent protein yields, which can be commercialized. 17 There may be further advantages of recombinant systems that possibly work only at a laboratory level. For example a range of constructs have been made for type II collagen, where specific "D-period" repeats, about 234 amino acids each, have been removed or substituted into the structure, allowing a better understanding of collagen structure and function.…”