Single-Cell Phenotyping of Complex Heterogeneous Tissue
The intervertebral disc (IVD) is a focus of regenerative medicine, with many ongoing clinical trials exploring disc regeneration through injection of stem cells. Anatomically a simple organ, the IVD is primarily comprised of two major tissue types: the annulus fibrosus (AF), which encapsulates the nucleus pulposus (NP). However, cellular composition and signaling cascades resulting in the different cell types present in the mature IVD are still a field of investigation and remain to be fully elucidated. The adult bovine IVD is a suitable model system that anatomically and histologically reflects the situation in human. We have repeatedly isolated primary cell lineages from the AF and NP tissues of bovine IVDs. Cells isolated from AF or NP tissue are typically heterogeneous in culture. Some cells exhibit several features of stem or progenitor cells and have been subjected to physiological and transcriptome-based phenotyping methods with single-cell resolution, which will be described here.
KeywordsIntervertebral disc Annulus fibrosus Nucleus pulposus PISH Single-cell gene expression Single-cell velocity Single-cell proliferation Bos taurus
This work was supported by the Bayard and Virginia Clarkson Endowment Fund granted to Thomas Lufkin.
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