Dr. Greenland is a Professor of Medicine at UCSF and Staff Physician at the San Francisco VA Health Care System. He received his undergraduate degree from Stanford and completed his PhD through the Harvard graduate program in Virology. He received an MD from the Harvard-MIT Division of Health Science and Technology.

He serves as an attending physician in the intensive care unit, pulmonary consult service, and outpatient pulmonary clinic at the SF VAHCS. He is an Associate Editor for the American Journal of Transplantation and served on the programming committee for the International Society for Heart and Lung Transplantation.

His research is focused on improving outcomes following lung transplantation. His group demonstrated that airway brush gene expression patterns can identify lung transplant recipients who at risk for graft failure or death. This novel diagnostic tool has substantial advantages over standard of care approaches and may accelerate clinical trials and personalize therapies to preserve the transplanted lung. His work has also uncovered novel patterns of rejection, including epithelial cell reprogramming, dysbiosis, and activation of T and Natural Killer cells in the airways of transplant recipients.

This research leverages a large bio-repository for cellular immunology, genomic, epigenetic, and bulk and single cell transcriptomic techniques, as well as mouse models to understand airway infections, acute and chronic lung transplant rejection, with a goal of improving outcomes following lung transplantation.