Synthetic biology tools have been used to develop switches, logic gates, timers, time-delay circuits, counters and oscillators to perform bio-computation in bacterial cells. Much of these are not as well characterized in multicellular populations of mammalian cells due to the prescence of cell-cell interactions which enable cell populations to communicate during development, adapt to the environment and to form or recognize patterns. Quorum sensing, a phenomenon of bacterial colonies wherein gene-expression is dependent on the population density, is a well-studied application of cell-cell communication in cell populations.
In this work by Bacchus et. al., published in Nature Biotechnology last year, scientists show how synthetic biology tools can enable mammalian cells to communicate one-to-one, just as people do in a telephonic conversation. For a one way call, the sender and receiver modules were engineered in different human embryonic kidney (HEK-293) cells and the signal strength varied linearly with the population of the receiver cells. In case of a cross-talk, both the sender and the receiver modules were engineered in the same cell, termed sender/receiver cells. Another cell was engineered to become processor cells which processed the signal generated into the signal to be received. The signal strength varied linearly with the population of sender/receiver cells.
Here is a presentation on the paper which I had to prepare for my animal tissue culture tutorial.
For a further proof-of-principle, the team were able to promote vasculogenesis by timed expression of vascular embryonic growth factor (VEGF) and angiopoietin-1 (Ang1) by modifiying the communication machinery in the previous case. The team hopes that
such bidirectional and multistep communication devices, inspired by naturally occurring fundamental processes, are key to the design and construction of next-generation synthetic mammalian networks that will likely comprise populations of specialized cells interconnected by orthogonal communication devices to fulfill complex computational operations.
Read the full article here:
Bacchus W, Lang M, El-Baba MD, Weber W, Stelling J & Fussenegger; Synthetic two-way communication between mammalian cells; Nature Biotechnology, Published online 16/9/12