The Krummey Lab is a part of the Department of Pathology at the Johns Hopkins School of Medicine.

Our research prioritizes understanding the cellular mechanisms of alloimmunity, with a concentration on manipulating various cosignaling receptors and antigen recognition pathways to restrain the key lymphocytes principally involved in graft rejection. With the use of MHC tetramers, transgenic mouse models, and high-dimensional flow cytometry, we focus on mouse- and human-graft specific CD8+ T cells, CD4+ T cells, and B cells.

Transplantation is a life-saving procedure against a variety of diseases. Despite technical advances vastly improving early outcomes after transplant, long-term survival of transplanted organs has remained stagnant for the better part of three decades. A major cause of graft loss is immune-mediated rejection, which traditionally has be classified as acute or chronic based on its occurrence early or late after transplantation. Recently, this consensus has shifted to defining a graft rejection by its immunologic characteristics, either antibody-mediated or T cell-mediated (cellular rejection). This is because modern discoveries have identified the true major contributor to graft failures that occur many years after transplantation: not chronic rejection, but rather the cumulative impact of T cell-mediated acute rejection as a risk factor for later graft loss. Thus, original approaches to specifically prohibit and/or treat T cell-mediated acute rejection are of major significance for improving post-transplant outcomes.

HLA compatibility has also proven to be paramount for graft rejection. Originally, this was believed to be at the cellular level, then the single HLA protein level, and now at the epitope or molecular mismatch level. Specifically, HLA class II epitope-level mismatch has been identified as a risk factor for graft rejection, and multiple studies have identified specific epitopes within HLA class II peptides that are thought to be highly pathogenic. Few techniques directly measure antibody responses against specific regions of HLA proteins, but such measurements could provide both new information about the strength and character of alloimmunity and serve as an important new tool to study allogeneic B cells and antibody-secreting cells.

Lauren Jantzie, professor of pediatrics and vice chair of research for the Department of Pediatrics, received her Ph.D. in neurochemistry from the University of Alberta in 2008. In 2013 she completed her postdoctoral fellowship in the Department of Neurology at Boston Children's Hospital & Harvard Medical School and became faculty at the University of New Mexico. Dr. Jantzie then joined the faculty Departments of Pediatrics (Neonatal-Perinatal Medicine) and Neurology at Johns Hopkins University and the Kennedy Krieger Institute in January 2019.

The Jantzie lab investigates the pathophysiology of encephalopathy of prematurity, and pediatric brain injury common to infants and toddlers. Dr. Jantzie is dedicated to understanding disease processes in the developing brain as a means to identifying new therapeutic strategies and treatment targets for perinatal brain injury. Her lab studies neural substrates of cognition and executive function, inhibitory circuit formation, the role of an abnormal intrauterine environment on brain development, mechanisms of neurorepair and microglial activation and polarization.

Using a diverse array of clinically relevant techniques such as MRI, cognitive assessment, and biomarker discovery, combined with traditional molecular and cellular biology, the Jantzie lab is on the front lines of translational pediatric neuroscience.

The Stivers Lab is broadly interested in the biology of the RNA base uracil when it is present in DNA. Our work involves structural and biophysical studies of uracil recognition by DNA repair enzymes, the central role of uracil in adapative and innate immunity, and the function of uracil in antifolate and fluoropyrimidine chemotherapy. We use a wide breadth of structural, chemical, genetic and biophysical approaches that provide a fundamental understanding of molecular function. Our long-range goal is to use this understanding to design novel small molecules that alter biological pathways within a cellular environment. One approach we are developing is the high-throughput synthesis and screening of small molecule libraries directed at important targets in cancer and HIV-1 pathogenesis.