On March 16, 2024, a Mass General Brigham team performed the first xenotransplantation of a gene-edited pig kidney into a patient. A new study, published in Nature Medicine, reports on the patient’s immune response against the pig kidney. 

Leonardo V. Riella, MD, PhD

The research team, led by Thiago J. Borges, PhD, and Leonardo V. Riella, MD, PhD, found that the transplanted kidney initially functioned well. However, despite the use of strong drugs to suppress the immune system, the patient experienced a type of rejection caused by T cells within the first week, likely due to residual immune cells in the lymph nodes. 

The rejection episode was successfully treated, and the study found no evidence of antibody mediated rejection, the most common cause of graft failure in transplantation.

However, ongoing immune responses persisted, highlighting a key unresolved challenge in xenotransplantation.

Thiago J. Borges, PhD

These findings suggest that improving xenotransplantation outcomes will require not only suppression of adaptive immunity, but also better control of innate immune pathways through targeted drug therapies or additional donor genetic modifications.

The study also suggests that circulating pig donor DNA in the bloodstream could act as a promising, non-invasive biomarker for the early detection of injury in transplanted organs.  

Paper Cited:

Ribas, G. T., Cunha, A. F., Avila, J. P., Giarraputo, A., Morena, L., Lima, K., Gassen, R. B., Chen, J. Y., Lin, J. R., Santagata, S., Avillach, C. T., Ryback, B. A., Lindner, M. S., Bercovici, S., Rosales, I. A., Kawai, T., Nakaya, H. I., Colvin, R. B., Borges, T. J., & Riella, L. V. (2026). Immune profiling in a living human recipient of a gene-edited pig kidney. Nature medicine, 32(1), 270–280. https://doi.org/10.1038/s41591-025-04053-36 | Read the paper 

Summary reviewed by: 

Thiago J. Borges, PhD, and Leonardo V. Riella, MD, PhD