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SoRelle, J. A.

Publications and source records attributed to SoRelle, J. A..

3 recordsLinked to original sources

DPP9-mediated inflammasome repression protects against checkpoint inhibitor lung toxicity

Over one million patients receive cancer immunotherapy annually, yet the mechanisms underlying life-threatening immune-mediated toxicities remain poorly understood. Checkpoint inhibitor pneumonitis (CIP) is the leading cause of immunotherapy-related mortality, with a case fatality rate approaching 10%, and no genetic risk factors have been described to date. We identified Dipeptidyl-peptidase 9 (DPP9) as the first genetic susceptibility gene for CIP in a clinico-genomics cohort of 4,397 patients treated with immune checkpoint inhibitors. Mechanistically, DPP9 suppresses CARD8 inflammasome activation and IL-18 secretion in human monocytes, a pathway which is engaged prior to CIP onset, with IL-18 selectively elevated in the plasma of patients who subsequently develop CIP. Myeloid-restricted ablation of Dpp8 and Dpp9 in mice recapitulated the pulmonary histopathological and immunological hallmarks of CIP, including granuloma formation, accumulation of IFN{gamma}-producing T cells and monocyte-derived macrophages. Each of these phenotypes were driven by excessive IL-18 secretion. Together, these findings establish DPP9 as a genetic determinant of CIP and nominate IL-18 blockade as a mechanistically rational therapeutic strategy.

immunology↗

PPa1 insufficiency drives lysosomal storage disease and inflammatory macrophage expansion in the bone marrow.

Inorganic pyrophosphatase-1 (PPa1) is an essential enzyme proposed to limit accumulation of the ubiquitous metabolic byproduct inorganic pyrophosphate, yet its role beyond a general housekeeping function remains poorly understood. We generated viable hypomorphic alleles of PPa1 through random mutagenesis in mice and unexpectedly found that PPa1 insufficiency causes a lysosomal storage disease of the bone marrow. Mutant mice developed impaired hematopoiesis and defective skeletal mineralization in a hematopoietic-intrinsic manner. The bone marrow was infiltrated by glycolipid-laden macrophages that were marked by high Spp1 and CD14 expression, blunted lysosomal acidification, metabolic stress, and a distinct inflammatory transcriptional program. Consistent with a lysosomal storage defect, PPa1-deficient bone marrow accumulated elevated levels of long-chain glucosyl-sphingolipids and sphingosine. These findings identify PPa1 as a previously unrecognized regulator of lysosomal function in myeloid cells that restrains inflammatory macrophage expansion and prevents bone marrow lysosomal storage pathology.

immunology↗

Differences in systemic immune parameters in individuals with lung cancer according to race

IntroductionRacial and ethnic disparities in the presentation and outcomes of lung cancer are widely known. To evaluate potential factors contributing to these observations, we measured systemic immune parameters in Black and White patients with lung cancer. MethodsPatients scheduled to receive cancer immunotherapy were enrolled in a multi-institutional prospective biospecimen collection registry. Clinical and demographic information were obtained from electronic medical records. Pre-treatment peripheral blood samples were collected and analyzed for cytokines using a multiplex panel and for immune cell populations using mass cytometry. Differences between Black and White patients were determined and corrected for multiple comparisons. ResultsA total of 187 patients with non-small cell lung cancer (Black, 19; White, 168) were included in the analysis. There were no significant differences in baseline characteristics between Black and White patients. Compared to White patients, Black patients had significantly lower levels of CCL23 and CCL27, and significantly higher levels of CCL8, CXCL1, CCL26, CCL25, CCL1, IL-1 b, CXCL16, and IFN-{gamma} (all P<0.05, FDR<0.1). Black patients also exhibited greater populations of non-classical CD16+ monocytes, NKT-like cells, CD4+ cells, CD38+ monocytes, and CD57+ gamma delta T cells (all P<0.05). ConclusionsBlack and White patients with lung cancer exhibit several differences in immune parameters, with Black patients exhibiting greater levels of numerous pro-inflammatory cytokines and cell populations. The etiology and clinical significance of these differences warrant further evaluation.

cancer biology↗