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Background Cytomegalovirus (CMV) is the major and most common opportunistic infection complicating lung transplant (LTX). The aim of this study was to analyse the epidemiological aspects of CMV infection in lung transplant patients subject to a pre-emptive anti-CMV approach and to study the impact of this infection on lung transplant outcome, in terms of onset of chronic lung allograft dysfunction (CLAD). Methods This single-centre retrospective study enrolled 87 LTX patients (median age 55.81 years; 41 females, 23 single LTX, 64 bilateral LTX). All patients were managed with a pre-emptive anti-CMV approach. The incidences of the first episode of CMV infection, 1, 3, 6 and 12 months after LTX, were 12.64%, 44.26%, 50.77% and 56.14%. A median interval of 41 days elapsed between LTX and the first episode of CMV infection. The median blood load of CMV-DNA at diagnosis was 20,385 cp/ml; in 67.64% of cases, it was also the peak value. Patients who had at least one episode had shorter CLAD-free survival. Patients who had three or more episodes of CMV infection had the worst outcome. Results CMV infection was confirmed to be a common event in lung transplant patients, particularly in the first three months after transplant. It had a negative impact on transplant outcome, being a major risk factor for CLAD. The hypothesis that lower viral replication thresholds may increase the risk of CLAD is interesting and deserves further investigation., Author(s): David Bennett [sup.1], Laura Bergantini [sup.1] [sup.2], Pierluigi Ferrara [sup.1] [sup.2], Maria Grazia Cusi [sup.3] [sup.4], Sabino Scolletta [sup.2] [sup.5], Francesca Montagnani [sup.4] [sup.6], Piero Paladini [sup.2] [sup.7], Piersante [...]

Toscana virus (TOSV) is an arthropodborne virus, belonging to the genus Phlebovirus, that was first isolated in Monte Argentario in 1971 from the sand flies Phlebotomus perniciosus and P. perfiliewi [...]

The severe acute respiratory syndrome coronavirus 2 variant JN.1 recently emerged as the dominant variant despite having only one amino acid change on the spike (S) protein receptor binding domain (RBD) compared with the ancestral BA.2.86, which never represented more than 5% of global variants. To define at the molecular level the JN.1 ability to spread globally, we interrogated a panel of 899 neutralizing human monoclonal antibodies. Our data show that the single leucine-455–to–serine mutation in the JN.1 spike protein RBD unleashed the global spread of JN.1, likely occurring by elimination of more than 70% of the neutralizing antibodies mediated by IGHV3-53/3-66 germlines. However, the resilience of class 3 antibodies with low neutralization potency but strong Fc functions may explain the absence of JN.1 severe disease. Editor's summary: New variants of SARS-CoV-2 continue to emerge and enable viral immune evasion. Using a panel of 899 human monoclonal neutralizing antibodies (nAbs), Paciello et al. examined antibody neutralization activity and effector functions against the recently dominant JN.1 variant. Compared with the ancestral BA.2.86 strain, around two-thirds of nAbs lost neutralization activity against JN.1, including most derived from the immunoglobulin heavy chain V gene (IGHV) 3-53 and 3-66 germlines. The remaining nAbs were only detected in individuals with a history of multiple vaccinations and Omicron breakthrough infections. Among nAbs that could bind the JN.1 spike protein, Fc functions were largely retained and primarily driven by class 3 antibodies that bind outside of the ACE2 binding region, possibly explaining the absence of JN.1 severe disease despite strong evasion of class 1/2 nAbs. —Claire Olingy [ABSTRACT FROM AUTHOR]

Monoclonal antibodies (mAbs) are one of the most important classes of biologics with high therapeutic and diagnostic value, but traditional methods for mAbs generation, such as hybridoma screening and phage display, have limitations, including low efficiency and loss of natural chain pairing. To overcome these challenges, novel single B cell antibody technologies have emerged, but they also have limitations such as in vitro differentiation of memory B cells and expensive cell sorters. In this study, we present a rapid and efficient workflow for obtaining human recombinant monoclonal antibodies directly from single antigen-specific antibody secreting cells (ASCs) in the peripheral blood of convalescent COVID-19 patients using ferrofluid technology. This process allows the identification and expression of recombinant antigen-specific mAbs in less than 10 days, using RT-PCR to generate linear Ig heavy and light chain gene expression cassettes, called "minigenes", for rapid expression of recombinant antibodies without cloning procedures. This approach has several advantages. First, it saves time and resources by eliminating the need for in vitro differentiation. It also allows individual antigen-specific ASCs to be screened for effector function prior to recombinant antibody cloning, enabling the selection of mAbs with desired characteristics and functional activity. In addition, the method allows comprehensive analysis of variable region repertoires in combination with functional assays to evaluate the specificity and function of the generated antigenspecific antibodies. Our approach, which rapidly generates recombinant monoclonal antibodies from single antigen-specific ASCs, could help to identify functional antibodies and deepen our understanding of antibody dynamics in the immune response through combined antibody repertoire sequence analysis and functional reactivity testing. [ABSTRACT FROM AUTHOR]

Fluoroquinolones (FQs) represent an class of antibiotics of medical importance, but their use has been restricted due to their ecologic impact and associated side effects. The reduction of FQs use is an important goal of antimicrobial stewardship programs (ASP). This work describes an ASP focused on overall antibiotics and FQs consumption reduction. From January 2021, an ASP was implemented in a 700-bed teaching hospital. The ASP was based on: (i) antibiotics consumption monitoring system (DDD/100 bed days); (ii) mandatory antibiotic prescription-motivation (using a dedicated informatic format) with the goal of >75% of motivated prescriptions; and (iii) data feedback and training on FQs use indications. We evaluated the impact of the intervention on overall systemic antibiotics and FQs consumption according to the objectives posed by Italian PNCAR (National Action Plan on Antimicrobial Resistance). A decrease of 6.6% in antibiotic use was observed (2019 vs. 2021). Notably, the FQs consumption fell by 48.3% from 7.1 DDD/100 bd in 2019 to 3.7 DDD/100 bd in 2021 (p < 0.001). After six months of mandatory antibiotic prescription-indication, all units achieved the target set. The study suggests that a simple, bundled ASP intervention can be rapidly effective obtaining the objectives of PNCAR on the reduction of overall antibiotics and FQs consumption. [ABSTRACT FROM AUTHOR]

Peripheral immune-checkpoint blockade with mAbs to programmed cell death receptor-1 (PD-1) (either nivolumab or pembrolizumab) or PD-Ligand-1 (PDL1) (atezolizumab, durvalumab, or avelumab) alone or in combination with doublet chemotherapy represents an expanding treatment strategy for metastatic non-small cell lung cancer (mNSCLC) patients. This strategy lays on the capability of these mAbs to rescue tumor-specific cytotoxic T lymphocytes (CTLs) inactivated throughout PD-1 binding to PD-L1/2 in the tumor sites. This inhibitory interactive pathway is a physiological mechanism of prevention against dangerous overreactions and autoimmunity in case of prolonged and/or repeated CTL response to the same antigen peptides. Therefore, we have carried out a retrospective bioinformatics analysis by single-cell flow cytometry to evaluate if PD-1/PD-L1-blocking mAbs modulate the expression of specific peripheral immune cell subsets, potentially correlated with autoimmunity triggering in 28 mNSCLC patients. We recorded a treatment-related decline in CD4+ T-cell and B-cell subsets and in the neutrophil-to-lymphocyte ratio coupled with an increase in natural killer T (NKT), CD8+PD1+ T cells, and eosinophils. Treatment-related increase in autoantibodies [mainly antinuclear antibodies (ANAs) and extractable nuclear antigen (ENA) antibodies] as well as the frequency of immune-related adverse events were associated with the deregulation of specific immune subpopulations (e.g., NKT cells). Correlative biological/clinical studies with deep immune monitoring are badly needed for a better characterization of the effects produced by PD-1/PD-L1 immune-checkpoint blockade. [ABSTRACT FROM AUTHOR]