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Altan-Bonnet, G. Y.

Publications and source records attributed to Altan-Bonnet, G. Y..

2 recordsLinked to original sources

The 1000+ mouse project: large-scale spatiotemporal parametrization and modeling of preclinical cancer immunotherapies

Preclinical studies of chimeric antigen receptor (CAR)-T cell immunotherapies are often based on monitoring bioluminescent tumors implanted in mice to assess anti-tumor cytotoxicity. Here, we introduce maRQup (murine automatic Radiance Quantification and parametrization), an easy-to-use method that automatically processes bioluminescent tumor images for quantitative analysis. We demonstrate the ability of maRQup to analyze CAR-T cell treatments over >1,000 tumor-bearing mice. We compare CD19-targeting CAR-T cells comprising either a CD28 or a 4-1BB costimulatory domain, and found the former controlled the tumor burden better initially, while the latter reduced the frequency of tumor relapse. We also applied maRQup to demonstrate faster tumor growth during the initial growth phase as compared to the relapse phase and to spatiotemporally analyze the high variability in immunotherapeutic control of tumors, based on their anatomical location. maRQup provides quantitative and statistically-robust insights on preclinical experiments that will contribute to the optimization of immunotherapies.

immunology↗

β-Coronaviruses use lysosomal organelles for cellular egress.

{beta}-Coronaviruses are a family of positive-strand enveloped RNA viruses that include the severe acute respiratory syndrome-CoV2 (SARS-CoV2). While much is known regarding their cellular entry and replication pathways, their mode of egress remains uncertain; however, this is assumed to be via the biosynthetic secretory pathway by analogy to other enveloped viruses. Using imaging methodologies in combination with virus-specific reporters, we demonstrate that {beta}-Coronaviruses utilize lysosomal trafficking for egress from cells. This pathway is regulated by the Arf-like small GTPase Arl8b; thus, virus egress is insensitive to inhibitors of the biosynthetic secretory pathway. Coronavirus infection results in lysosome deacidification, inactivation of lysosomal degradation and disruption of antigen presentation pathways. This coronavirus-induced exploitation of lysosomes provides insights into the cellular and immunological abnormalities observed in patients and suggests new therapeutic modalities.

microbiology↗