Figure 3.

Microbioprinting of vasculature and skin models. A) Rendering of the microvasculature model developed by Pataky et al. B–D) Slices of the model and confocal images according to the slicing planes labeled in (A). E) Composite image showing perfusion of the alginate microchannel with fluorescent beads flowing at 0 and 2 s. The scale bars in (B)–(E) represent 200 μm. A–E) Adapted with permission.^[58] Copyright 2012, Wiley-VCH. F) Schematic of the FRESH process developed by Feinberg and co-workers, where a hydrogel (green) is extruded and cross-linked in a gelatin slurry (yellow). Upon completion, the system is heated to 37 °C to melt the gelatin and release the scaffold. G) Example of arterial trees printed in fluorescent alginate (green) via the FRESH method, H) where a stable lumen was formed with and defined vessel wall <1 mm thick. Scale bars are 2.5 and 1 mm in (G) and (H), respectively. F–H) Adapted with permission.^[62] Copyright 2015, American Association for the Advancement of Science. I) Schematic of the microbioprinting setup used by Koch et al. (left), where the pressure of a laser-induced vapor bubble propels a cell-laden hydrogel and yields a micropatterned grid structure (right) of fibroblasts (green) and keratinocytes (red). J) Histology image showing seven alternating layers of red and green keratinocytes, where each colored layer consists of four microbioprinted sublayers. Scale bar is 500 μm in (I)–(K). I–K) Adapted with permission.^[22] Copyright 2012, Wiley-VCH.