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Novelli, A.

Publications and source records attributed to Novelli, A..

4 recordsLinked to original sources

Systemic-to-mucosal trafficking of memory B cells contributes to humoral immunity in the upper respiratory tract

Systemic vaccination induces serum antibodies and circulating memory B cells, protects from severe disease, but does not ensure sterilizing immunity in the upper respiratory tract, where many respiratory pathogens initiate infection. How systemic memory B cells contribute to mucosal immunity remains unclear. Using multiparametric flow cytometry, single-cell RNA and V(D)J sequencing, and functional analyses of paired blood and nasal/oropharyngeal samples, we characterized human B cells across systemic and mucosal compartments. Swab-derived B cells transcriptionally overlap with circulating activated memory B cells while exhibiting distinct features of activation, tissue retention, and spontaneous IgA/IgG secretion. Approximately 6% of mucosal B-cell clones were shared with blood, indicating systemic-mucosal connectivity. Both infection and vaccination expanded two circulating antigen-specific activated memory B cells subsets, whereas antigen-specific B cells accumulated in the upper respiratory tract only following local inflammation. The finding that B-cell recruitment is reactive rather than preemptive may explain the limited efficacy of parenteral vaccines and provides a rationale for developing integrated systemic-mucosal vaccination strategies.

immunology↗

Investigating mitochondrial gene expression patterns in Drosophila melanogaster using network analysis to understand aging mechanisms

The process of aging is a complex phenomenon that involves a progressive decline in physiological functions required for survival and fertility. To better understand the mechanisms underlying this process, the scientific community has utilized several tools. Among them, mitochondrial DNA has emerged as a crucial factor in biological aging, given that mitochondrial dysfunction is thought to significantly contribute to this phenomenon. Additionally, Drosophila melanogaster has proven to be a valuable model organism for studying aging due to its low cost, capacity to generate large populations, and ease of genetic manipulation and tissue dissection. Moreover, graph theory has been employed to understand the dynamic changes in gene expression patterns associated with aging and to investigate the interactions between aging and aging-related diseases. In this study, we have integrated these approaches to examine the patterns of gene co-expression in Drosophila melanogaster at various stages of development. By applying graph-theory techniques, we have identified modules of co-expressing genes, highlighting those that contain a significantly high number of mitochondrial genes. We found important mitochondrial genes involved in aging and age-related diseases in Drosophila melanogaster, including UQCR-C1, ND-B17.2, ND-20, and Pdhb. Our findings shed light on the role of mitochondrial genes in the aging process and demonstrate the utility of Drosophila melanogaster as a model organism and graph theory in aging research.

bioinformatics↗

Episignatures stratifying ADNP syndrome show modest correlation with phenotype

ADNP syndrome, also known as Helsmoortel-van Der Aa syndrome, is a neurodevelopmental condition associated with intellectual disability/developmental delay, autism spectrum disorder, and multiple medical comorbidities. ADNP syndrome is caused by mutations in the activity-dependent neuroprotective protein (ADNP). A recent study identified genome-wide DNA methylation changes in 22 individuals with ADNP syndrome, adding to the group of neurodevelopmental disorders with an epigenetic signature. This methylation signature segregated those with ADNP syndrome into two groups, based on the location of the mutations. Here, we conducted an independent study on 24 individuals with ADNP syndrome and replicated the existence of the two, mutation-dependent ADNP episignatures. To probe whether the two distinct episignatures correlate with clinical outcomes, we used deep behavioral and neurobiological data from two prospective cohorts of individuals with a genetic diagnosis of ADNP syndrome. We found limited phenotypic differences between the two ADNP groups, and no evidence that individuals with more widespread methylation changes are more severely affected. Also, in spite of the methylation changes, we observed no profound alterations in the blood transcriptome of individuals with ADNP syndrome. Our data warrant caution in harnessing methylation signatures in ADNP syndrome as a tool for clinical stratification, at least with regards to behavioral phenotypes.

developmental biology↗

Ceftolozane-tazobactam pharmacokinetics during extracorporeal membrane oxygenation in a lung transplant recipient

Ceftolozane-tazobactam pharmacokinetics during extracorporeal membrane oxygenation (ECMO) has not been previously studied. In this work we report on the ceftolozane and tazobactam plasmatic levels in a lung transplant recipient during ECMO, treated with ceftolozane-tazobactam (2g/1g, intravenously every 8 h, 1 h infusion) for a Pseudomonas aeruginosa pulmonary infection. Ceftolozane Cmax and Cmin, monitored during 96 hrs, remained above 60 and 20 g/mL, respectively, with optimal drug exposure (100% %TMIC). Tazobactam levels were above 1.9 g/mL.

pharmacology and toxicology↗