Publications by authors named "T Hatziioannou"

Therapeutic monoclonal antibodies (mAbs) against SARS-CoV-2 become obsolete as spike substitutions reduce antibody binding. To induce antibodies against conserved receptor-binding domain (RBD) regions for protection against SARS-CoV-2 variants of concern and zoonotic sarbecoviruses, we developed mosaic-8b RBD-nanoparticles presenting eight sarbecovirus RBDs arranged randomly on a 60-mer nanoparticle. Mosaic-8b immunizations protected animals from challenges from viruses whose RBDs were matched or mismatched to those on nanoparticles.

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The presence of abundant tumor stroma is a prominent characteristic of pancreatic ductal adenocarcinomas (PDAC) that potentially influences disease progression and therapy response. This study aims to investigate immune cell infiltration and epigenetic profiles in tumor cell enriched ("Tumor") and stroma cell enriched ("Stroma") regions within human PDAC tissue samples. By comparing those regions, we identified 25,410 differentially methylated positions (DMPs) distributed across 6,963 unique genes.

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Background: DNA methylation profiles have emerged as potential predictors of therapeutic response in various solid tumors.

Objective: This study aimed to analyze the DNA methylation profiles of patients with stage IV metastatic melanoma undergoing first-line immune checkpoint inhibitor treatment and evaluate their correlation with a radiological response according to immune-related Response Evaluation Criteria in Solid Tumors (iRECIST).

Methods: A total of 81 tissue samples from 71 patients with metastatic melanoma (27 female, 44 male) were included in this study.

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The glycosylation of viral envelope proteins can play important roles in virus biology and immune evasion. The spike (S) glycoprotein of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) includes 22 N-linked glycosylation sequons and 17 O-linked glycosites. We investigated the effect of individual glycosylation sites on SARS-CoV-2 S function in pseudotyped virus infection assays and on sensitivity to monoclonal and polyclonal neutralizing antibodies.

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Article Synopsis
  • The emergence of SARS-CoV-2 variants with reduced vaccine effectiveness shows the need for new vaccine designs that provide wider protection.
  • This study evaluates the antibody response from a novel vaccine, the Spike Ferritin Nanoparticle (SpFN), in non-human primates, particularly focusing on the antibodies that target different regions of the virus's Spike protein.
  • Six potent neutralizing antibodies were identified, demonstrating broad effectiveness against various sarbecovirus variants, including Delta and Omicron, with one antibody showing strong protection in murine studies.
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