These images are stills from a blood vessel animation. Maya omni emitters were instanced with models of blood components, given random-rotational attributes. The translucent blobby shape is a white blood cell rolling along the side of the vessel. It is emitting purple Y-shaped antibodies.
The shaders used for the red blood cells and the velvety outer surface of the vessel came from Gael McGill's Villus Capillary tutorial at Molecular Movies