Preparing and Processing Complex Tissue Constructs Composed of Cellular Spheroids for Histological Examination

Abstract

Using cellular spheroids to build tissues and organs is a rapidly emerging technology that will have great impact on the biomedical industry. As tissues are fabricated in vitro, it will be critical to histologically examine tissue composition, function and organization for comparison with native tissues. Conventional automated histologically methods are not recommended for fixation and processing of tissues composed of spheroids due to their delicate nature and the need to preserve tissue morphology. Given this, there is a need to develop a manual method to prepare and process tissues composed of cellular spheroids for histological sectioning and examination. Here, we report a manual processing technique developed for preparing larger tissues composed of spheroids for histological examination based on our lab's work using magnetic forces to pattern and assemble tissues composed of Janus Magnetic Cellular Spheroids for tissue engineering applications. The results presented here contribute to understanding the organization of cells, studying extracellular matrix content, analyzing phenotypic expression and localizing iron oxide magnetic nanoparticles in tissues composed of Janus Magnetic Cellular Spheroids.