Biospray techniques, allow the direct jet-processing of living cells with biopolymers and other biomaterials for controlled deposition to a pre-orientated architecture. These techniques facilitate the direct formation of composite three-dimensional living architecture’s mimicking native tissues/organs. Such structures are most useful for fundamental cell and molecular biology studies to those of a more clinical application relevant to our health sciences for our well-being. In fact these techniques are soon becoming platform biotechnologies having a plethora of applications.
In a laboratory setting the ability to develop three-dimensional architectures with pin-point precision could be used for modeling both functional and disease tissue. This has several implications for investigating basic cellular behavior ranging from cell adhesion, migration to other functions such as differentiation when studying stem cells. This approach is useful as custom tissues could be formed in a number of desired three-dimensional patterns for understanding cellular features, which could then be explored for studying random cellular microenvironments as those found in native tissue. In addition biospray techniques (such as bio-electrosprays, cell electrospinning and aerodynamically assisted bio-jets/threads) allow large scale processing and enable high through-put tissue fabrication. This is most useful for example from screening, drug discovery and development to the significant reduction in the use of model organisms for large scale studies. Hence implying the development of a humane approach for carrying out biomedical research.
Clinically these direct cell handling approaches have implications for repairing, replacing and rejuvenating damaged or ageing tissues. At present these techniques have undergone rigorous testing which have seen them been put through both intensive in vitro and in vivo studies. These studies have demonstrated the complete inertness of these approaches for handling a wide range of cells spanning immortalized, primary and stem cells (Including iPs) to those model organisms at very early stages of development. An interesting application that has resulted for our work, addresses both utility in the laboratory and the clinic. This has risen as a direct result of our investigations into aerodynamically assisted bio-jets (AABJ). This technology has previously been investigated in another manifestation (in co-flow fluidic systems) for focusing streams of liquid.
Briefly, AABJ is a technology which exploits a pressure differential over an exit orifice for drawing a media jet from a needle holding a fluid flow. Previous investigations have seen this technology used for aerosol based research, in our hands this technology has undergone exploration for its handling of living biological materials spanning from cells to embryos. Our investigations have elucidated the technology having no negative effects on the handled biological materials. Therefore we are pursuing the utility of this technology for development as a sheathless flow cell most useful in cytometry. At present all flow cells explore a varied quantity of sheathflow for driving a stream of single cells past a laser system for analyzing the cell’s physio-chemical nature. Although these flow cells in their many manifestations have greatly contributed to flow cytometry, they have limitations. AABJ as a flow cell makes redundant sheath flow and yet possess the ability to jet very high viscosity cell suspensions, making this technology unique.
Thus the development of this multifaceted technology as a flow cell has several implications not only to cytometry but also to the controlled distribution of cells and embryos in three-dimensions, which would be useful for fabricating tailored tissues and more. Therefore contributing to regenerative biology and medicine, and having implications for utility in the real world.
Suwan Jayasinghe
Suwan N. Jayasinghe is a researcher at University College London, and a member of the Materials Today Editorial Board.