The first aim of the project was the achievement of a functional DNA machinery in the presence of in vitro cell cultures. To do this, we relied on enzyme-based DNA program. A compromise between the standard cell culture medium and the DNA machinery medium was developed to full-fill the desires of both without being deleterious for neither of them. With this new “cell-DNA buffer”, we could achieve the viability of both the cells and the DNA machinery for at least 48h. We observed that cells would internalize DNA with relatively easiness. We decided to mark the DNA with a fluorescent molecule, which made cells fluorescent upon its internalization (image 1 attached). With this approach, although simple, it satisfied the initial objective of having an interaction between the extracellular DNA machinery and the living cells. Once we had the interacting extracellular active medium, we were able to change the program of the DNA machinery so that it would respond in a temporal and spatial manner. For the spatial experiments, we had to come up with a rectangular device which allowed us to create a two-band pattern, such as a polish flag. In one side of the rectangular device, the fluorescence DNA was released and internalized by the cells, while on the other side there were no release, and hence no modification of the cells. We thus demonstrated that a synthetic extracellular program can transfer positional information to living cells, emulating an archetypal mechanism of pattern formation in embryo development. To our knowledge, this has not been accomplished without the use of microfluidics (and hence the introduction of shear stress). With these pioneer results, we foresee that active extracellular media could be advantageously applied to in vitro biomolecular tracking, tissue engineering or smart bandages.
These findings have been submitted for publication at a high impact factor journal. The first version of manuscript can be found in the open access repository biorxiv. Together with a member of the host group a side project reported on another golden access publication. To further exploit this work, the researcher has attended 3 congress, one of which has been invited by the organizers to give an oral contribution, to disseminate its work within the scientific community.
To help disseminate science, the researcher has been an organizer of the Paris Biological Physics Community Day 2019, where the idea is to promote divulgation by young scientist. At a more general public dissemination, the researcher achieved to encourage and establish the active participation of the host department into the “fête de la science”, a scientific demonstration for the general public with the idea of transmitting and encouraging the French young community into the scientific world. Furthermore, during the duration of the grant, several students from different schools and grades have attended the lab (and the host department) for traineeships of different durations, with the objective of transmitting them how the scientific community works and motivate them. In addition, the researcher was trusted with the supervision of a bachelor and a Master student. As a non-standard out-reach activity, two divulging videos explaining the basic mechanism of the DNA programs used in this project have been developed (YouTube).
