Laser Printing of Single Cells: Statistical Analysis, Cell Viability, and Stress

Abstract

Methods to print patterns of mammalian cells to various substrates with high resolution offer unique possibilities to contribute to a wide range of fields including tissue engineering, cell separation, and functional genomics. This manuscript details experiments demonstrating that BioLP Biological Laser Printing, can be used to rapidly and accurately print patterns of single cells in a noncontact manner. Human osteosarcoma cells were deposited into a biopolymer matrix, and after 6 days of incubation, the printed cells are shown to be 100% viable. Printing low numbers of cells per spot by BioLP is shown to follow a Poisson distribution, indicating that the reproducibility for the number of cells per spot is therefore determined not by the variance in printed volume per drop but by random sampling statistics. Potential cell damage during the laser printing process is also investigated via immunocytochemical studies that demonstrate minimal expression of heat shock proteins by printed cells. Overall, we find that BioLP is able to print patterns of osteosarcoma cells with high viability, little to no heat or shear damage to the cells, and at the ultimate single cell resolution.

Biofabrication: an overview of the approaches used for printing of living cells

“…At the same time, this group developed the improved BioLP™ approach in an attempt to limit direct interaction between the laser and sensitive biomaterials (Barron et al 2004a). This technique also proved capable of depositing highly viable human osteosarcoma cells (Barron et al 2005) and olfactory ensheating cells (Othon et al 2008) onto Matrigel™ substrates.…”

Depth-controlled laser-induced jet injection for direct three-dimensional liquid delivery

“…Previous studies on LIFT systems used either solid receiver substrates when patterning non-sensitive material [21], or receiver slides coated with a thin layer of damping material such as Matrigel or gelatin to increase cell viability for bioprinting applications [23][24][25]. Here, to investigate direct three-dimensional liquid delivery, the receiver substrate consists of a 300 μm thick soft gelatin substrate.…”

“…As shown in Fig. 4, fitting the experimental bead distributions by Poisson distributions [23] reveals that an average 1.15 ± 0.06 and 2.35 ± 0.14 beads per dose are, respectively, delivered for 2.4 ± 0.2 and 6.3 ± 0.5 J cm −2 laser fluences, whereas combining the measured dose volume (see blue squares in Fig. 3b) with the 10 7 beads/mL concentration indicates that 0.75 ± 0.15 and 1.4 ± 0.22 bead per dose would, respectively, be expected.…”

Scaffolds in Regenerative Endodontics: A Review.

“…In theory, an ink-jet-like device is used to dispense layers of cells suspended in a hydrogel [106] to recreate the structure of the tooth pulp tissue. The three-dimensional cell printing technique can be used to precisely position cells [107] , and this method has the potential to create tissue constructs that mimic the natural tooth pulp tissue structure. The ideal positioning of cells in a tissue engineering construct would include placing odontoblastoid cells around the periphery to maintain and repair dentin, with fibroblasts in the pulp core supporting a network of vascular and nerve cells.…”