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Mesenchymal stem cells (MSCs) are multipotent cells that can be readily harvested from animal body tissues and grown in culture. MSC cultures contain fat stem cells (pre-adipocytes) in addition to other mesenchymal progenitor cell types. Farm animal MSCs provide a cell source of choice for cultivated fat production, an important sector within the wider cultivated meat industry. However, MSCs are highly heterogenous by nature, containing only a fraction of bona-fide progenitor cells capable of differentiating selectively into adipocytes thus limiting the potential for industrial cultivated fat applications. Elucidating the molecular signatures of pre-adipocytes from farm animal species would facilitate selective enrichment of MSCs to enable efficient scale-up culture of fat. Here we describe bulk RNA sequencing datasets from clonal cell populations obtained by single-cell fluorescence activated sorting of porcine MSCs, and classified as having either high (H) or low (L) fat-forming (adipogenic) capacity in culture, as determined by chemically-induced differentiation followed by staining with the lipid dye, Oil Red O. We present raw file and results of bioinformatics analyses of sequencing data. PCA plots showed partial overlapping of gene expression profiles from H and L cell populations. Differential gene expression analyses revealed 30 upregulated transcripts and 67 downregulated transcripts in H relative to L clones, with upregulated transcripts including several known adipogenic genes such as PPARG and FABP4. These datasets are publicly available for use in workflows, and could provide novel information on pre-adipocyte biology in livestock in turn helping improve the sustainability of both traditional and cultivated meat production.

Cultivated meat promises to address some of the pressing challenges associated with large-scale production of animals for food. An important limitation to realising such promise is the lack of readily available cell lines that can be expanded robustly for scale-up culture while maintaining the capacity to differentiate into tissues of interest, namely fat and muscle. Here, we report a porcine mesenchymal stem cell line (FaTTy) which, uniquely, upon spontaneously immortalisation acquired enhanced adipogenic efficiency, close to 100%, that has now been maintained for over 200 population doublings. FaTTy is able to differentiate with high efficiency in both 2D and 3D contexts and produces mature adipocytes upon prolonged differentiation. Moreover, FaTTy adipocytes display fatty acid profiles largely similar to native pig fat but with higher monounsaturated-to-saturated ratios. FaTTy displays minor aneuploidy, characterised by lack of Y chromosome, and lacks typical genetic or functional properties of tumorigenic cells. These highly distinctive characteristics, together with its non-genetically modified nature, make FaTTy a very attractive, potentially game-changing resource for food manufacturing, and particularly cultivated meat.

Culture of muscle cells from livestock species has typically involved laborious enzyme-based approaches that yield heterogeneous populations with limited proliferative and myogenic differentiation capacity, thus limiting their use in physiologically-meaningful studies. This study reports the use of a simple explant culture technique to derive progenitor cell populations from porcine muscle that could be maintained and differentiated long-term in culture. Fragments of semitendinosus muscle from 4 to 8 week-old piglets (n = 4) were seeded on matrigel coated culture dishes to stimulate migration of muscle-derived progenitor cells (MDPCs). Cell outgrowths appeared within a few days and were serially passaged and characterised using RT-qPCR, immunostaining and flow cytometry. MDPCs had an initial mean doubling time of 1.4 days which increased to 2.5 days by passage 14. MDPC populations displayed steady levels of the lineage-specific markers, PAX7 and MYOD, up until at least passage 2 (positive immunostaining in about 40% cells for each gene), after which the expression of myogenic markers decreased gradually. Remarkably, MDPCs were able to readily generate myotubes in culture up until passage 8. Moreover, a decrease in myogenic capacity during serial passaging was concomitant with a gradual increase in the expression of the pre-adipocyte markers, CD105 and PDGFRA, and an increase in the ability of MDPCs to differentiate into adipocytes. In conclusion, explant culture provided a simple and efficient method to harvest enriched myogenic progenitors from pig skeletal muscle which could be maintained long-term and differentiated in vitro, thus providing a suitable system for studies on porcine muscle biology and applications in the expanding field of cultured meat.