FIG. 6.

Fabrication of a scaffold based on 3D reconstruction of COLIV images from a postnatal day 2 ventricle and illustration of the theoretical application of the ECM developmental blueprint to the fabrication of ECM-based biomaterials for cardiac regeneration. (A) A single section, from a data set of 20 serial sections, showing COLIV immunolabel in a postnatal day 2 ventricle. This is the fourth section in the series. The stack of images was used to create a 3D virtual reconstruction of the 20 anti-COLIV-labeled serial sections and a solid sterolithographic rendering was generated from the stack of serial sections. Multiphoton excitation-based fabrication was then used to create a 3D physical reconstruction using trimethylolpropanetriacrylate. Rose Bengal, used as the photoactivator, provides the fluorescence for the image shown. Construct was imaged as a z-stack using multiphoton microscopy and reconstructed using Imaris. Scale bar=50 μm. V indicates blood vessel; *Identifies representative structural mimics. (B) To understand the environment required to support the proliferation and differentiation of cardiomyocytes, we examined the distribution and relative amounts of four ECM components in the ventricles of developing mouse hearts using complementary methods of analysis, including SHG imaging of intact ventricles, antibody labeling of left ventricles, and qPCR of both ventricles. These data can be quantified to generate profiles of changes in the ECM composition during heart development. This ECM developmental profile can guide to select a desired cell behavior such as rapid cellular proliferation, encouraged differentiation or limit migration. The appropriate ECM blueprint could serve as a template to build a matrix supportive of the desired cell behaviors. The stage-optimized matrix could be probed to understand cell–matrix interactions better or directly delivered to the site of injury for therapeutic intervention. Color images available online at www.liebertpub.com/tea