T-Cell 303 (Human Immune System) I take part in an informal, weekly "PsyPhi" (Psychology and Philosophy) discussion group and through it I met Fredrik Trulsson, a member of the Center for Scientific Computing (sciCORE) of the University of Basel. Almost by chance I asked him "Do you have any cool data you'd like to visualize?" and he said: "Actually... yes!" That data resulted in this visualization of an actual T-Cell of the human immune system. The team Fredrik is part of takes a collection of cells, freezes them in time by encasing them in a transparent resin block a few millimeter per side and out of it carefully creates hundreds of slices 40 nanometer thick with a microtome machine. The slices are then scanned with an electron scanning microscope resulting in hundreds of beautiful and insightful greyscale images that are used for further analysis. Nobody however had ever put the slices back together to create a three-dimensional object out of them, which is where I come in. Fredrik and his department kindly provided the data for one T-Cell in the form of folders containing hundreds of CSV files, one per slice, each in turn containing a two-dimensional array of the density values measured by the electron scanning microscope. Each folder contained only one type of component of the cell, for example only the Mitochondria, only the Plasma Membrane and so on, which was instrumental to assign different colors to each. In Houdini I wrote a little python snippet to ingest the data into volumetric objects with a resolution of approximately 1000x1000x200 voxels. Initially I used Redshift's volume shader to render all the components of the cell, but eventually I left only the Plasma Membrane (in dark yellow) and the Nucleus (in blue) as volumetric renderings. The other organelles, i.e. the orange Mitochondria, were converted from volumes to isosurfaces to polygonal surfaces and rendered with the standard Redshift shader. Besides the components already mentioned in this animation one can observe in bright yellow the Golgi Complex, in bright green the Endoplasmatic Reticulum Sheets, in semi-transparent green (reflecting their lower densities) the Endoplasmatic Reticulum Tubules and in red the Multivescicular Bodies. A Lipid Droplet, in magenta, is visible in right hemisphere of the cell. I loved working on this task, figuring out how to ingest this type of data and then finding ways to process it and visualize it effectively, displaying it with clarity without loosing its wonderful visual complexity. I am particularly struck by the intricacy of this cell in comparison to the typical illustrations of cells we see in school books. I'm glad Fredrik and his colleagues gave me this opportunity and I thank them for their support, enthusiasm and encouragement for the duration of the project.