Page 37 - SaxoCell Annual Report22/23

Reg. ZellTWund
Med.

The ZellTWund project focuses on the generation and utilization of purified pro-regenerative cells
from human skin, in particular fibroblast subpopulations, for the purpose of skin regeneration in
chronic, non-healing wounds, involving degradable biopolymers.

Project lead: Jan-Christoph Simon & Sandra Franz

Partners: University Hospital Leipzig, University of Leipzig, Helmholtz Center Munich

Fibroblasts are a diverse population of cells with different functions that adapt to environmental
signals. Several fibroblast subtypes have been identified in mouse studies, some of which are
associated with regenerative processes in development and wound healing.

To identify pro-regenerative fibroblasts in human skin, existing single cell sequencing data from
human skin were analyzed and compared with known data from mouse studies. This resulted in
three fibroblast clusters that differed between fetal and adult cells. Assignment of marker genes
from mouse studies demonstrated that certain fetal subclusters resembled mouse fibroblast
populations. Pro-regenerative marker genes identified in reindeer antler fibroblasts were also
included in the analysis and found in fibroblast subclusters of human fetal skin. Furthermore,
different expression profiles were identified in fibroblast subclusters of adult human skin,
indicating possible different functions.

In addition, skin culture models were developed to test the tolerability, integration and efficacy of
a pro-regenerative wound dressing. This includes a new ex-vivo wound healing model from human
skin samples that includes all three layers of the skin and can be maintained in long-term culture
by special media. The ex-vivo wound healing model using human skin will be used for preclinical
testing of the wound dressing. We entered into a new industry collaboration with HAN Biomedical,
who is already providing us with clinically used biomaterials for the incorporation of the pro-
regenerative fibroblasts. As a result of this collaboration, HAN established a European research
office in Leipzig. Further studies are needed to characterize the fibroblast clusters and confirm the
integration of the cells into the skin tissue.

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