Researchers at Nanjing Agricultural University have developed a new method for producing cultured meat that addresses some of the key challenges facing the industry. The team, led by Shijie Ding, Chunbao Li, and Guanghong Zhou, published their findings in Food Materials Research on June 25, 2025 (DOI: 10.48130/fmr-0025-0006).
Cultured meat production relies on growing animal stem cells into edible tissues. Muscle stem cells, known as satellite cells, are particularly important because they can regenerate and form muscle fibers. Traditionally, these cells are grown using fetal bovine serum (FBS), which provides nutrients and growth factors. However, FBS is costly, its composition varies between batches, and it raises ethical and safety concerns.
To overcome these obstacles, the researchers designed a serum-free medium to support both the proliferation and differentiation of porcine satellite cells. They used an iterative optimization strategy starting with a basic DMEM/F12 medium supplemented with essential components like ITS-X, BSA, Y-27632, and several growth factors. Through stepwise improvements—adding lipids, non-essential amino acids, antioxidants, hydrocortisone, forskolin, HGF, dexamethasone, and LPA—they created Formula 3 that improved short-term cell proliferation.
After further refining concentrations of each component to create Formula 4 (named A19), they achieved robust proliferation rates (>90% viability) across multiple cell passages while maintaining high levels of myogenic regulators such as PAX7, MYOD, and MYOG compared to serum-based controls.
The team also addressed cellular senescence by applying CRISPR/Cas9 gene editing to remove CDKN2A from satellite cell lines. These modified CDKN2A−/− lines showed enhanced long-term proliferation over 18 passages without losing their ability to differentiate into mature muscle fibers at early stages.
"By eliminating the need for animal-derived serum," said the research team in their publication,"the approach enhances food safety, ethical acceptance,and consistency in manufacturing." They also noted that "the CRISPR-based CDKN2A knockout cells provide a renewable source of muscle progenitors,reducing dependence on repeated animal biopsies."
For differentiation into edible tissue structures,the researchers developed a Version 4.0 medium enabling formation of elongated,myosin heavy chain-positive myotubes from long-term cultured CDKN2A−/− cells.Seeding these engineered cells onto plant-based three-dimensional edible scaffolds produced meat-like constructs with improved texture parameters,such as chewiness and gumminess.
This dual approach—using serum-free media alongside genetically engineered immortalized cell lines—offers solutions for reducing costs,increasing scalability,and improving consistency in cultured meat production.The study's methods may be adaptable for other livestock species beyond pork.
