It is well established that cells interact with their environment which could be mechanical, chemical or topographical cues. These are all factors that are important in vivo, thus it is of interest to understand the importance of these cues on cell response and tissue regeneration with the aim to harness the knowledge and apply that to medical devices.
Specifically for chemical and topographical patterning dimensions comparable to a cell or smaller are investigated which means from 10 microns to 10 nanometres. To help answering such questions we take an interdisciplinary approach of combining micro- and nanofabrication with polyomic approach.
The applicant profile for our activities span from engineers and physicists developing and fabricating pattern libraries, over chemists to develop new materials and chemical patterning to mathematicians and computer scientists for data analysis and model development.
Nanofabrication and mastering
We make use of nanofabrication techniques known from the semiconductor industry to make specific and precise patterns. Central to that approach is the use of electron beam lithography whereby features as small as 5 nm can be realised. This CAD-driven design process enables us to explore a large parameter space for feature sizes, geometries and densities with the aim to manufacture high-content libraries for analysis. For biological experiments we use a replication process whereby the nanofabrication master can be copied repeatedly in a polymeric substrate.
Cellular response and control
The fabricated polymeric substrates can then be used to explore the cellular response to the designs made. We know that different cells respond differently to similar patterns, thus the aim is to better understand this response in the hope that the knowledge can be applied to medical devices to achieve targeted responses. Cells include mammalian cell lines as well as human stem cells. More recently we have extended the studies to include bacteria too.
With the nanofabrication process it is possible to manufacture libraries of topographical and chemical patterns which can be addressed in a high-content approach. From these libraries numerous images are acquired by microscopy techniques which then needs to be analysed and paired with the underlying pattern. This high-content approach enables a screen of potentially relevant patterns for device applications.
The high-content analysis provides a rapid method of assessing cellular responses, it is also necessary to understand the cellular functions. Specific targets will be explored further using gene arrays and proteomic analysis. This will build a biochemical picture of the cellular activities on the patterns and structured investigated.
To collectively analysis and understand the data acquired, we apply a range of different bioinformatics tools. This spans from freely available high-content image analysis software to data mining of mass spectrometry data with the long term aim to establish models describing substrate design and cellular response.