In 1990 Pellegrini established the first urethral stem cell cultures for humans, which could be used to regenerate the urethra in patients with posterior hypospadias.

[11] For the following two years, Pellegrini and De Luca observed initial stem cell patients, when it became obvious that they could scale the technology.

[12] In 2008 Pellegrini and De Luca co-founded the Holostem Terapie Avanzate, a biotechnology spin-out that develops advanced therapy producets that use epithelial stem cell cultures.

[13] They developed a culture system that creates limbal stem cell for the regeneration of corneas, which can restore vision to patients ocular burns who are deemed incurable.

[18] In 2020 Graziella Pellegrini and Michele De Luca, shared the Louis-Jeantet Prize for Medicine for the development of epithelial stem cell-based regenerative therapy in patients with severe eye and skin disease.