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Serreze, D. V.

Publications and source records attributed to Serreze, D. V..

3 recordsLinked to original sources

Mapping the genetic landscape establishing a tumor immune microenvironment favorable for anti-PD-1 response in mice and humans

Identifying host genetic factors modulating immune checkpoint inhibitor (ICI) efficacy has been experimentally challenging because of variations in both host and tumor genomes, differences in the microbiome, and patient life exposures. Utilizing the Collaborative Cross (CC) multi-parent mouse genetic resource population, we developed an approach that fixes the tumor genomic configuration while varying host genetics. With this approach, we discovered that response to anti-PD-1 (aPD1) immunotherapy was significantly heritable in four distinct murine tumor models (H2 between 0.18-0.40). For the MC38 colorectal carcinoma system (H2 = 0.40), we mapped four significant ICI response quantitative trait loci (QTL) localized to mouse chromosomes (mChr) 5, 9, 15 and 17, and identified significant epistatic interactions between specific QTL pairs. Differentially expressed genes within these QTL were highly enriched for immune genes and pathways mediating allograft rejection and graft vs host disease. Using a cross species analytical approach, we found a core network of 48 genes within the four QTLs that showed significant prognostic value for overall survival in aPD1 treated human cohorts that outperformed all other existing validated immunotherapy biomarkers, especially in human tumors of the previously defined immune subtype 4. Functional blockade of two top candidate immune targets within the 48 gene network, GM-CSF and high affinity IL-2/IL-15 signaling, completely abrogated the MC38 tumor transcriptional response to aPD1 therapy in vivo. Thus, we have established a powerful cross species in vivo platform capable of uncovering host genetic factors that establish the tumor immune microenvironment configuration propitious for ICI response.

cancer biology↗

Human CD8+ T-cells Require Glycolysis to Elicit Effector Function

Targeting human T-cell metabolism for modulating immune function requires an understanding of macronutrient utilization. Using metabolic inhibition during activation of human naive CD8+ T-cells, we demonstrate blocking glycolysis or mitochondrial respiration prevents T-cell proliferation. However, after activation and differentiation, the metabolic program changes. Inhibition of glycolysis abolished cytotoxic T-lymphocyte (CTL) activity, whereas mitochondrial inhibition had no effect on CTL lytic function. Studies with uniformly labeled 13C-glucose confirmed CTL convert the majority of glucose to lactate. The role of glycolysis in CTL function was assessed using NOD models of Type 1 diabetes (T1D). Treatment of NOD models with a glycolysis inhibitor resulted in reduced and delayed T1D incidence and significantly preserved {beta}-cell mass. We conclude glycolysis and mitochondrial ATP production are essential for efficient T-cell activation, but only glycolysis is essential for CTL lytic function. These data suggest targeting glycolysis in CTLs is a promising pathway to prevent T-cell-mediated autoimmunity.

immunology↗

A hypermorphic Nfkbid allele represents an Idd7 locus gene contributing to impaired thymic deletion of autoreactive diabetogenic CD8+ T-cells in NOD mice.

In both NOD mice and humans, the development of type 1 diabetes (T1D) is dependent in part on autoreactive CD8+ T-cells recognizing pancreatic {beta}-cell peptides presented by often quite common MHC class I variants. Studies in NOD mice previously revealed the common H2-Kd and/or H2-Db class I molecules expressed by this strain acquire an aberrant ability to mediate pathogenic CD8+ T-cell responses through interactions with T1D susceptibility (Idd) genes outside the MHC. A gene(s) mapping to the Idd7 locus on proximal Chromosome 7 was previously shown to be an important contributor to the failure of the common class I molecules expressed by NOD mice to mediate the normal thymic negative selection of diabetogenic CD8+ T-cells. Using an inducible model of thymic negative selection and mRNA transcript analyses we initially identified an elevated Nfkbid expression variant is likely an NOD Idd7 region gene contributing to impaired thymic deletion of diabetogenic CD8+ T-cells. CRISPR/Cas9-mediated genetic attenuation of Nfkbid expression in NOD mice resulted in improved negative selection of autoreactive diabetogenic AI4 and NY8.3 CD8+ T-cells. These results indicated allelic variants of Nfkbid represent an Idd7 gene contributing to the efficiency of intrathymic deletion of diabetogenic CD8+ T-cells. However, while enhancing thymic deletion of pathogenic CD8+ T-cells, ablation of Nfkbid expression surprisingly accelerated T1D onset in NOD mice likely at least in part by numerically decreasing regulatory T- and B-lymphocytes (Tregs/Bregs), thereby reducing their peripheral immunosuppressive effects.

immunology↗