# Exploration of Preservation Methods for Utilizing Porcine Fetal-Organ-Derived Cells in Regenerative Medicine Research

## TL;DR

This study explores how to best preserve porcine fetal organs to use their cells in regenerative medicine and xenotransplantation research.

## Contribution

The study identifies optimal preservation methods for porcine fetal kidney, heart, and liver cells to enhance their viability for regenerative applications.

## Key findings

- Kidney cells dissociated and aggregated after whole-organ vitrification differentiated into glomeruli and tubules in vivo.
- Heart cells frozen after dissociation retained pulsating muscle cells similar to non-frozen samples.
- A direct tissue perfusion technique successfully obtained viable liver parenchymal cells.

## Abstract

Human pluripotent stem cells have been employed in generating organoids, yet their immaturity compared to fetal organs and the limited induction of all constituent cell types remain challenges. Porcine fetal progenitor cells have emerged as promising candidates for co-culturing with human progenitor cells in regeneration and xenotransplantation research. This study focused on identifying proper preservation methods for porcine fetal kidneys, hearts, and livers, aiming to optimize their potential as cell sources. Extracted from fetal microminiature pigs, these organs were dissociated before and after cryopreservation–thawing, with subsequent cell quality evaluations. Kidney cells, dissociated and aggregated after vitrification in a whole-organ form, were successfully differentiated into glomeruli and tubules in vivo. In contrast, freezing hearts and livers before dissociation yielded suboptimal results. Heart cells, frozen after dissociation, exhibited pulsating heart muscle cells similar to non-frozen hearts. As for liver cells, we developed a direct tissue perfusion technique and successfully obtained highly viable liver parenchymal cells. Freezing dissociated liver cells, although inferior to their non-frozen counterparts, maintained the ability for colony formation. The findings of this study provide valuable insights into suitable preservation methods for porcine fetal cells from kidneys, hearts, and livers, contributing to the advancement of regeneration and xenotransplantation research.