Biology subjects

Romanelli, A.

Publications and source records attributed to Romanelli, A..

6 recordsLinked to original sources

bioRxiv2026

Identification of ICAM-1-targeting DNA aptamers as a host-directed strategy to inhibit Human Rhinovirus infection

Exacerbations of respiratory viral infections significantly contribute to morbidity and healthcare burden. Among these viruses, Human Rhinoviruses (HRVs) are the most frequent causative agents of upper respiratory tract infections. To date, over 150 HRV serotypes have been identified, classified into three species: HRV-A, HRV-B, and HRV-C. No antiviral therapies are currently available against this viral family, largely due to the high serotype diversity and limited cross-protection. The major group of HRVs relies on the Intercellular Adhesion Molecule-1 (ICAM-1) receptor to infect airway epithelial cells, making ICAM-1 an attractive target for broad-spectrum therapeutic interventions. Here, we report the development of nucleic acid-based aptamers designed to disrupt ICAM-1-HRV binding and thereby prevent viral infection. Aptamers are single-stranded DNA molecules that fold into precise three-dimensional structures, enabling highly specific protein recognition. Using a Systematic Evolution of Ligands by EXponential Enrichment (SELEX) approach guided by a minimal peptide mimicking the ICAM-1 viral binding interface, a library of >1024 random single-stranded DNA sequences was screened. Through iterative rounds of selection, we identified eight candidate 77-nt DNA aptamers, which were subsequently evaluated for their potential using in silico and in vitro assays, as well as functional assays in human epithelial cells. From this strategy, two lead aptamers were selected that effectively inhibited HRV-A16 replication in a concentration-dependent manner, as measured by viral titers (TCID assay) and viral RNA quantification by RT-PCR. These findings demonstrate the potential of ICAM-1-targeting aptamers as antiviral agents capable of preventing HRV entry. By targeting a host receptor and creating a protective barrier at the cell surface, this approach may offer a broadly applicable strategy against multiple HRV serotypes, paving the way for the development of novel antiviral interventions. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=131 SRC="FIGDIR/small/717810v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@130d8org.highwire.dtl.DTLVardef@2dd09borg.highwire.dtl.DTLVardef@1da744eorg.highwire.dtl.DTLVardef@109ea5b_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

bioRxiv2025

Amphibian-derived peptide analog TB_KKG6K: A powerful drug candidate against Candida albicans with anti-biofilm efficacy

Candida albicans, a commensal and opportunistic fungal pathogen, is a major clinical concern due to its ability to cause infections ranging from mild mucosal conditions to life-threatening systemic diseases, particularly in immunocompromised patients. Its capacity to form biofilms on medical devices further complicates treatment by enhancing antifungal resistance and immune evasion. In the search for novel therapeutic strategies, the lysine-enriched amphibian-derived temporin B analog, TB_KKG6K, has emerged as a promising antifungal agent. This study demonstrates that TB_KKG6K exhibits potent activity against planktonic C. albicans cells, with a low potential to induce adaptation or resistance, even after prolonged exposure. TB_KKG6K has no adverse impact on the anti-Candida efficacy of standard antifungal drugs like amphotericin B, caspofungin, fluconazole or 5-flucytosine, when applied in combination. Additionally, TB_KKG6K effectively reduces biofilm maturation on silicone elastomers, a material commonly used in medical devices, further highlighting its therapeutic potential. These data together with our previous documentation of minimal cytotoxicity and irritation potential in human cells, makes TB_KKG6K a strong candidate for combating both planktonic and biofilm-associated C. albicans infections. These findings underscore the dual efficacy of TB_KKG6K and its potential to address the challenges posed by C. albicans in clinical settings.

microbiology↗

bioRxiv2022

The membrane activity of the amphibian Temporin B peptide analog TB_KKG6K sheds light on the mechanism that kills Candida albicans

Temporin B (TB) is a 13 amino acid long, cationic peptide secreted by the granular glands of the European frog Rana temporaria. We could recently show that the modified TB peptide analog TB_KKG6K rapidly killed planktonic and sessile Candida albicans at low {micro}M concentrations and was neither hemolytic nor cytotoxic to mammalian cells in vitro. The present study aimed to shed light into its mechanism of action, with a focus on its fungal cell membrane activity. We utilized different fluorescent dyes to prove that it rapidly induces membrane depolarization and permeabilization. Studies on model membrane systems revealed that the TB analog undergoes hydrophobic and electrostatic membrane interactions showing a preference for anionic lipids and identified phosphatidylinositol and cardiolipin as possible peptide targets. Fluorescence microscopy using FITC-labelled TB_KKG6K in the presence of the lipophilic dye FM4-64 indicated that the peptide compromises membrane integrity and rapidly enters C. albicans cells in an energy independent manner. Peptide treated cells analyzed by cryo-based electron microscopy exhibited no signs of cell lysis; however, subcellular structures were disintegrated, suggesting that intracellular activity may form part of the killing mechanism of the peptide. Taken together, this study proved that the TB_KKG6K compromises C. albicans membrane function, which explains the previously observed rapid, fungicidal mode of action and promises its great potential as a future anti-Candida therapeutic. ImportanceFungal infections with the opportunistic human pathogen C. albicans are associated with high moratility rates in immunocompromised patients. This is partly due to the yeasts ability to rapidly develop resistance towards currently available antifungals. Small, cationic, membrane-active peptides are promising compounds to fight against resistance development as many of them effectuate rapid fungal cell death. This fast killing is believed to hamper the development of resistance, as the fungi do not have sufficient time to adapt to the antifungal compound. We prevously reported that the synthetic variant of the amphibian Temporin B peptide, TB_KKG6K, rapidly kills C. albicans. In the current study, the mechanism of action of the TB analog was investigated. We show that this TB analog is membrane-active and impairs cell membrane function, highlighting its potential to be developed as an attractive alternative anti-C. albicans therapeutic, which may hinder the development of resistance.

microbiology↗

bioRxiv2022

Combination of the Systemin peptide with the beneficial fungus Trichoderma afroharzianum T22 improves plant defense responses against pests and diseases

Trichoderma spp. are among the most widely used plant beneficial fungi in agriculture. A novel approach to enhance their effectiveness in plant defense is to use the fungi in combination with bioactive molecules including plant-derived compounds. Here, we show that plant treatment with Trichoderma afroharzianum (strain T22) and Systemin (Sys), a tomato plant peptide active in triggering plant defense, confers protection against the fungal pathogens Fusarium oxysporum, Botrytis cinerea and the insect pest Tuta absoluta. The observed defensive response was associated with increased accumulation of metabolites and transcripts involved in the Jasmonic acid (JA) pathway. Our findings suggest that the innovative combination of T. afroharzianum T22 and Sys can result in a more effective and robust control of different biotic stress agents.

genetics↗

bioRxiv2018

Effect of fosfomycin, Cynara scolymus extract, deoxynivalenol and their combinations on intestinal health of weaned piglets

Intestinal health of weaning piglets was studied after oral treatments with fosfomycin (FOS), Cynara scolymus extract (CSE), deoxynivalenol (DON) and their combinations. Piglets were divided in groups and received different treatments during 15 days, namely DON (1mg/kg of feed), FOS administered into the drinking water (30 mg/kg b.w.), CSE (300 g/ton of feed) and all possible combinations including a control group that received clean balanced diet. At day 15, three piglets from each group were euthanized and gastrointestinal tract samples were immediately taken to evaluate pH, bacteriology (enterobacteria and lactic acid bacteria), volatile fatty acids concentration (VFAs), disaccharidases activity (lactase, sucrase and maltase), histology (intestinal absorptive area [IAA] and goblet cells count) and adherence of bacteria to intestinal mucus. Animals receiving FOS and CSE treatments exhibited evident beneficial intestinal effects compared to animals receiving diets free from these compounds. This was revealed by a lower enterobacteria population together with a lower E/L, an enhanced production of butyric acid, an increased enzymatic activity (particularly maltase), and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal mucus. Interactions between both treatments resulted in similar beneficial effects as their individual administration. On the contrary, DON produced detrimental effects on intestinal health as a decrease was observed on volatile fatty acids production, enzymatic activity and goblet cells count in animals receiving diets containing sub- toxic concentrations of this mycotoxin. The knowledge of the intestinal effects of these compounds contributes to understand the physiological and pathological gut changes and their potential productive consequences.

systems biology↗

bioRxiv2017

Highly efficient DNA-free gene disruption in the agricultural pest Ceratitis capitata by CRISPR-Cas9 RNPs

The Mediterranean fruitfly Ceratitis capitata (medfly) is an invasive agricultural pest of high economical impact and has become an emerging model for developing new genetic control strategies as alternative to insecticides. Here, we report the successful adaptation of CRISPR-Cas9-based gene disruption in the medfly by injecting in vitro pre-assembled, solubilized Cas9 ribonucleoprotein complexes (RNPs) loaded with gene-specific sgRNAs into early embryos. When targeting the eye pigmentation gene white eye (we), we observed a high rate of somatic mosaicism in surviving G0 adults. Germline transmission of mutated we alleles by G0 animals was on average above 70%, with individual cases achieving a transmission rate of nearly 100%. We further recovered large deletions in the we gene when two sites were simultaneously targeted by two sgRNAs. CRISPR-Cas9 targeting of the Ceratitis ortholog of the Drosophila segmentation paired gene (Ccprd) caused segmental malformations in late embryos and in hatched larvae. Mutant phenotypes correlate with repair by non-homologous end joining (NHEJ) lesions in the two targeted genes. This simple and highly effective Cas9 RNP-based gene editing to introduce mutations in Ceratitis capitata will significantly advance the design and development of new effective strategies for pest control management.

genetics↗