In the 1990s, Dr. Riddell and colleagues performed studies designed to block life-threatening reactivation of cytomegalovirus after allogeneic hematopoietic stem cell transplantation (HCT). They provided the first proof-of-principle that antigen-specific T cells can be used to boost T cell immunity to a virus. Subsequent work focused on developing techniques to express genes in T cells that regulated their survival and redirected their specificity to cancer cells.
Dr. Riddell led the first human trial of adoptively transferred T cell clones to prevent cytomegalovirus infection after allogeneic HCT, and developed four subsequent trials of T cell therapy, including the first efforts to treat relapsed leukemia post-HCT and to use synthetic chimeric antigen receptor (CAR)-modified T cells of defined subset composition.
The Riddell Laboratory continues to focus on:
Dr. Riddell’s team has developed new techniques for isolation, expansion, genetic modification and reinfusion of T cells, and for monitoring safety, persistence, migration and function after transfer. Many of these innovative methods are now widely used. Demonstrations that naïve and memory T cell subsets can have superior persistence and efficacy after adoptive transfer informed new methods to rapidly isolate defined cell populations for clinical trials using T cells modified with specific CARs or T cell receptors (TCRs).