Brandon Triplett, MD

Since the first bone marrow transplant was performed at St. Jude in 1982, transformative scientific discoveries have expanded the indications for use, increased efficacy and improved the safety profile for this treatment modality. My research has primarily focused on integrating basic and translational research discoveries into cellular immune therapies that can be used to treat children with high-risk malignancies.   

Ideally, transplantation elicits a graft-versus-leukemia (GVL) effect, allowing donor natural killer (NK) cells and T cells to eradicate residual cancer cells without attacking healthy tissue and causing graft-versus-host-disease (GvHD). We aim to understand how to bolster early immune reconstitution to improve therapeutic outcomes, specifically for children receiving haploidentical donor cells.  

Haploidentical donor cells are genetically half identical to a patient’s cells. The HLAs present on donor cells are therefore partially mismatched to patient cells, which can lead to complications such as severe GvHD. Our work focuses on graft manipulation and combination immunotherapies within HLA-mismatched transplantation to improve efficacy and lower risks. 

Our studies have explored various ways to optimize donor cell sources to increase chances of transplantation success. Recently, we developed transplant protocol which uses sequential infusion of haploidentical CD34-enriched and CD45RA-depleted grafts followed by the infusion of NK cells from alloreactive donors. This protocol elicited a more rapid immune cell reconstitution and increased the GVL effect. By developing and optimizing graft design, our work stands to decrease the likelihood of relapse and increase the survival rates of children with high-risk disease. 

Certain high-risk hematological malignancies may also be treated with cellular therapies such as chimeric antigen receptor (CAR) T-cell therapy. A great deal of my clinical research has focused on conducting early phase clinical trials which utilize CAR T-cell therapy to treat children with relapsed or refractory blood cancers. We aim to make this treatment more inclusive, decrease the risks associated with it and better understand the long-term impact of this therapy on long-term survivors.  

Dr. Triplett is a physician scientist who received his medical degree from Saint Louis University (SLU) School of Medicine. He then completed a residency program in pediatrics at SLU before moving to Memphis, TN, where he completed a fellowship in pediatric hematology-oncology at St. Jude. Currently serving as Deputy Clinical Director and Member of the St. Jude faculty in the Department of Bone Marrow Transplantation and Cellular Therapy (BMTCT), Dr. Triplett has substantially expanded the donor pool for hematopoietic cell transplantation (HCT), developing and implementing several unique clinical trials aimed at treating children with very high-risk hematologic malignancies. Specifically, he is interested in HLA-mismatched related donor transplantation. Understanding the importance of training the next generation of physician scientists, Dr. Triplett is also dedicated to mentoring junior faculty members and BMTCT fellows at St. Jude.

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