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Biology subjects

Deshayes, S.

Publications and source records attributed to Deshayes, S..

3 recordsLinked to original sources

A novel microporous biomaterial vaccine platform for long-lasting antibody mediated immunity against viral infection.

Current antigen delivery platforms, such as alum and nanoparticles, are not readily tunable, thus may not generate optimal adaptive immune responses. We created an antigen delivery platform by loading lyophilized Microporous Annealed Particle (MAP) with aqueous solution containing target antigens. Upon administration of antigen loaded MAP (VaxMAP), the biomaterial reconstitution forms an instant antigen-loaded porous scaffold area with a sustained release profile to maximize humoral immunity. VaxMAP induced CD4+ T follicular helper (Tfh) cells and germinal center (GC) B cell responses in the lymph nodes similar to Alum. VaxMAP loaded with SARS-CoV-2 spike protein improved the magnitude and duration of anti-receptor binding domain antibodies compared to Alum and mRNA-vaccinated mice. A single injection of Influenza specific HA1-loaded-VaxMAP enhanced neutralizing antibodies and elicited greater protection against influenza virus challenge than HA1-loaded-Alum. Thus, VaxMAP is a platform that can be used to promote adaptive immune cell responses to generate more robust neutralizing antibodies, and better protection upon pathogen challenge.

immunology↗

Identification of an A20 critical region harboring missense variations that lead to autoinflammation

A20 haploinsufficiency (HA20) is an autoinflammatory disease caused by heterozygous loss-of-function variations in TNFAIP3, the gene encoding the A20 protein. Diagnosis of HA20 is challenging due to its heterogeneous clinical presentation and the lack of pathognomonic symptoms. While the pathogenic effect of TNFAIP3 truncating variations is clearly established, that of missense variations is difficult to determine. Herein, we identified a novel TNFAIP3 variation, p.(Leu236Pro), located in the A20 Ovarian Tumor (OTU) domain and demonstrated its pathogenicity. In the patients primary cells, we observed reduced A20 levels explained by enhanced degradation. We showed a disrupted ability of A20_Leu236Pro to inhibit the NF-{kappa}B pathway. Review of previously reported TNFAIP3 missense variations revealed that only 3/7 are pathogenic. Through structural modeling we showed that the residues involved in OTU pathogenic missense variations establish common interactions. Interpretation of newly identified missense variations is challenging, requiring, as illustrated here, functional demonstration of their pathogenicity. Together with functional studies, in-silico structure analysis is a valuable approach that allowed us to unveil a region within the OTU domain critical for A20 function.

genetics↗

KRAS signalling in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) arises from mesothelial cells lining the pleural cavity of asbestos-exposed individuals and rapidly leads to the development of pleural effusion and death. MPM harbours loss-of-function mutations in genes like BAP1, NF2, CDKN2A, and TP53, but isolated deletion of these genes alone in mice does not cause MPM and mouse models of the disease are sparse. Here we show that a significant proportion of human MPM harbour point mutations and copy number alterations in the KRAS proto-oncogene. These mutations are likely pathogenic, since ectopic expression of mutant KRASG12D in the pleural mesothelium of conditional mice causes MPM. Murine MPM cell lines derived from these tumours carry the initiating KRASG12D lesions, secondary Bap1 alterations, and human MPM-like gene expression profiles. Moreover, they are transplantable and actionable by KRAS inhibition. Our results indicate that KRAS mutations likely play an important and underestimated role in MPM, which warrants further exploration.

physiology↗