Tracy L. McGaha

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Lupus, a multigenic autoimmune condition in which a breakdown of tolerance results in the development of autoantibodies, leads to a variety of pathologic outcomes. Despite the heterogeneity of factors influencing disease susceptibility, we demonstrate that the partial restoration of inhibitory Fc receptor (FcgRIIB) levels on B cells in lupus-prone mouse(More)
Loss of tolerance in systemic lupus erythematosus (SLE) leads to the generation of autoantibodies, which accumulate in end-organs where they induce disease. Here we show that immunoglobulin (Ig)G2a and 2b autoantibodies are the pathogenic isotypes by recruiting FcgammaRIV expressing macrophages. Class switching, but not development, of IgM anti-self B cells(More)
Environmental factors including drugs, mineral oils and heavy metals such as lead, gold and mercury are triggers of autoimmune diseases in animal models or even in occupationally exposed humans. After exposure to subtoxic levels of mercury (Hg), genetically susceptible strains of mice develop an autoimmune disease characterized by the production of highly(More)
The tumor microenvironment is profoundly immunosuppressive. We show that multiple tumor types create intratumoral immune suppression driven by a specialized form of regulatory T cell (Treg) activation dependent on the PTEN (phosphatase and tensin homolog) lipid phosphatase. PTEN acted to stabilize Tregs in tumors, preventing them from reprogramming into(More)
Red blood cells (RBCs) from a rhesus D (RhD)-positive fetus that reach the bloodstream of an RhD-negative pregnant woman during birth can induce a pathogenic antibody (Ab) response against the RhD-positive RBCs, leading to fetal hemolytic disease in subsequent pregnancies. To prevent a pathogenic immune reaction, the RhD-negative mother receives serum(More)
In higher organisms, innate scavenging cells maintain physiologic homeostasis by removal of the billions of apoptotic cells generated on a daily basis. Apoptotic cell removal requires efficient recognition and uptake by professional and non-professional phagocytic cells, which are governed by an array of soluble and apoptotic cell-integral signals resulting(More)
The tumor microenvironment is profoundly immuno-suppressive, but exactly how this is coordinated and maintained remains poorly understood. We show that multiple transplantable and autochthonous mouse tumors actively elicit a population of highly suppressive regulatory T cells (Tregs) expressing the lipid phospha-tase PTEN. These PTEN+ Tregs co-expressed(More)
Inflammation is a disruptive force in the tissue microenvironment driving extracellular matrix reorganization, production of noxious effector molecules (superoxide, nitric oxide, peroxynitrite, ect.), hypoxia, and active consumption of nutrients required for biosynthesis including amino acids. Indoleamine 2,3 dioxygenase 1 (IDO1) is an intracellular,(More)
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