Juan Carlos Izpisua Belmonte

At a glance

• Juan Carlos Izpisua Belmonte is a Spanish biochemist and developmental biologist. A professor at the Salk Institute in La Jolla, California, since 1993, he is now a founding scientist and institute director at Altos Labs.
• He is best known for work on partial reprogramming: briefly exposing cells to the ‘Yamanaka factors’ so they regain features of younger cells without losing their identity.
• In a widely cited study (Cell, 2016), his team gave these factors in short cycles to mice with a premature-ageing disease; the animals lived longer and their tissues repaired better.
• His lab also works on tissue regeneration and embryology. Experiments with human–animal chimeras sparked a broad ethical debate.
• Altos Labs, founded in 2022 with very large investments, aims to understand disease and ageing better through this kind of ‘cell rejuvenation’.
• For longevity, his work shows that the biological age of cells can be partly reversed in the lab. There are no applications in humans yet.
• Takeaway: follow this field with interest, but be critical of products that already promise ‘reprogramming’ or ‘cell rejuvenation’.