Claudia Ghali

Scopus Publications

High glucose enhances inflammation-driven platelet adhesion to endothelial cells in vitro
Mariangela Scavone, Antonella Fioretti, Martina Molinaro, Claudia Ghali, Carla Martinelli, Tatiana Mencarini, Silvia Bozzi, Nadia Santo, Umberto Gianelli, Monica Miozzo, Marco Guazzi, Gian Marco Podda, Mario Cozzolino, Paola Ciceri
Scientific Reports, 2026
Endothelial and platelet dysfunction are central to vascular disease development. We established a simplified, reproducible 96-well plate model to assess platelet adhesion to endothelial cells under conditions mimicking in vitro endothelial dysfunction and platelet hyperactivation. Human aortic endothelial cells (HAEC) were treated with tumour necrosis factor-alpha (TNF-α, 20–50 ng/mL) and/or high glucose levels (30 mM) to replicate in vitro the states of inflammation and hyperglycaemia. Treated HAEC were then exposed to platelets from healthy volunteers. In some experiments, platelets were treated with tirofiban, a GP IIb/IIIa inhibitor, before HAEC exposure. Platelet adhesion was evaluated by fluorescence, transmission, and scanning electron microscopy. Conditions showing significant effects were subsequently confirmed using a microfluidic device under high shear conditions. TNF-α stimulation significantly increased platelet adhesion to HAEC. This was accompanied by morphological changes indicative of activation. High glucose alone had no significant effect but, when combined with TNF-α, it synergistically enhanced platelet adhesion under both static and dynamic flow conditions. Interestingly, adhesion was prevented by platelet pretreatment with tirofiban. This study demonstrates the utility of a straightforward experimental in vitro setup that allows for mechanistic studies regarding platelet-endothelial interaction. By combining simplicity with reproducibility, the model offers a valuable tool for investigating platelet-endothelium interactions. It also serves as a preclinical platform for evaluating therapeutic interventions aimed at reducing thrombotic risk in conditions of inflammation and hyperglycaemia.
Variables influencing the in vitro measurement of spontaneous aggregation of human platelets
Claudia Ghali, Antonella Fioretti, Mariangela Scavone, Elena Bossi, Bianca Clerici, Simone Birocchi, Evgeny Popov, Marco Centola, Gianmarco Podda, Marco Cattaneo
Haematologica, 2025
Not available.
Investigating the Interplay of SARS-CoV-2 RNAemia and Peripheral Inflammation in Platelet Dysfunction During Acute SARS-CoV-2 Infection
Mariangela Scavone, Roberta Rovito, Claudia Ghali, Antonella Fioretti, Bianca Clerici, Elena Bossi, Camilla Tincati, Andrea Santoro, Elisa Borghi, Gianmarco Podda, Giulia Marchetti
Pathogens and Immunity, 2025
Background: Circulating degranulated platelets have been described during acute SARS-CoV-2 infection and associated with COVID-19 complications. This study investigated the relationship between the presence of plasma SARS-CoV-2 RNA (ie, SARS-CoV-2 RNAemia), systemic inflammation, and platelet dysfunction in a group of patients with COVID-19. Unlike our previous publication, which focused on platelet characterization, this work explores potential determinants of platelet activation, based on a distinct subset of patients with available stored samples. Methods: Patients with COVID-19 were stratified by platelet δ-granule content using the luciferin/luciferase assay into 2 groups: normal (COVδ-norm) and low (COVδ-low). Plasma SARS-CoV-2 RNAemia (RT-qPCR), cytokines, and chemokines (Cytometric Bead Array) were quantified on plasma samples. Markers of platelet activation were measured by flow cytometry in whole blood. Results: A total of 75 patients with COVID-19 were enrolled; 57 presented normal levels of platelet δ-granule content (COVδ-norm) and 18 had low levels of platelet δ-granules (COVδ-low). Groups were comparable in terms of age, sex, comorbidities, and SARS-CoV-2 RNAemia levels. Patients in the COVδ-low group showed significantly higher chemokine and cytokine levels compared to those in the COVδ-norm group, with strong correlations between IL-6, as well as granulocyte-macrophage colony-stimulating factor (GM-CSF), with platelet degranulation parameters. A similar trend, albeit less pronounced, was observed when patients were stratified based on their platelet activation phenotype. Conclusions: These findings suggest that peripheral inflammation, rather than SARS-CoV-2 RNAemia, is associated with platelet dysfunction during acute SARS-CoV-2 infection.
Time-dependent in vitro variations of platelet count in samples from subjects with EDTA-induced pseudothrombocytopenia: A comparative analysis across different anticoagulants
Claudia Ghali, M. Scavone, Bianca Clerici, Elena Bossi, Antonella Fioretti, Chiara Pisetta, S. Birocchi, G. Vismara, Nadia Vozzo, Marco Cattaneo, G. Podda
British Journal of Haematology, 2024
For original data, please contact Gian Marco Podda ([email protected]). Table S1. Table S2. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Comprehensive investigation of platelet function in patients with cirrhosis
Anna Lecchi, Giulia Tosetti, Claudia Ghali, Silvia La Marca, Marigrazia Clerici, Lidia Padovan, Eti A. Femia, Massimo Primignani, Vincenzo La Mura, Pietro Lampertico, Flora Peyvandi, Armando Tripodi
Thrombosis Research, 2024
ReDIP, the Italian network for the diagnosis of congenital platelet function disorders
Marco Cattaneo, Claudia Ghali, Mariangela Scavone
Bleeding Thrombosis and Vascular Biology, 2024
Congenital platelet function disorders (cPFD) are associated with an increased risk of mucocutaneous bleeding of various levels of severity; they may be classified based on abnormalities of platelet components that share common characteristics: i) platelet receptors for adhesive proteins; ii) platelet receptors for soluble agonists; iii) platelet granules; iv) signal transduction pathways; v) procoagulant phospholipids; less well characterized PFD aregrouped in a sixth category of miscellaneous abnormalities [...].
A case of acquired transient bleeding diathesis associated with acquired platelet storage pool deficiency and defective thromboxane A2 production
Mariangela Scavone, Bianca Clerici, Eti Alessandra Femia, Claudia Ghali, Antonella Fioretti, Elena Bossi, Marco Cattaneo, Gian Marco Podda
Platelets, 2024
Acquired disorders of platelet function are an underdiagnosed cause of bleeding tendency. A 14-year-old girl developed moderate mucocutaneous bleeding two weeks after a Mycoplasma pneumoniae infection successfully treated with clarithromycin. The patient was referred to us 7 months later for laboratory investigation of the persisting bleeding diathesis. The patient's personal and family histories were negative for bleeding disorders. Complete blood count, von Willebrand Factor levels and coagulation tests were normal; platelet aggregation, ATP secretion, δ-granules content and serum thromboxane B2 levels were defective. At follow-up visits, laboratory parameters and the bleeding diathesis progressively normalized within 2 years. The patient's condition is compatible with a diagnosis of acquired Storage Pool Deficiency (SPD), associated with defective thromboxane A2 production. To our knowledge, this is the first case of acquired, transient SPD with spontaneous remission. The pathogenic role of Mycoplasma pneumoniae infection or clarithromycin is possible, albeit uncertain.
Impairment of platelet function in both mild and severe COVID-19 patients
Mariangela Scavone, Claudia Ghali, Mariagrazia Calogiuri, Matteo Sala, Elena Bossi, Tatiana Mencarini, Silvia Bozzi, Bianca Clerici, Simone Birocchi, Antonella Fioretti, Valeria Bono, Norma Maugeri, Giulia Marchetti, Marco Cattaneo, Gian Marco Podda
British Journal of Haematology, 2023
SummaryAbnormalities of platelet function were reported in patients with severe COVID‐19 (severe‐C), but few data are available in patients with mild COVID‐19 (mild‐C) and after COVID‐19 recovery. The aim of this study was to investigate platelet parameters in mild‐C patients (n = 51), with no evidence of pneumonia, and severe‐C patients (n = 49), during the acute phase and after recovery, compared to 43 healthy controls. Both mild‐C and severe‐C patients displayed increased circulating activated platelets, low δ‐granule content (ADP, serotonin), impaired platelet activation by collagen (light transmission aggregometry) and impaired platelet thrombus formation on collagen‐coated surfaces under controlled flow conditions (300/s shear rate). The observed abnormalities were more marked in severe‐C patients than in mild‐C patients. Overall, 61% (30/49) of mild‐C and 73% (33/45) of severe‐C patients displayed at least one abnormal platelet parameter. In a subgroup of just 13 patients who showed no persisting signs/symptoms of COVID‐19 and were re‐evaluated at least 1 month after recovery, 11 of the 13 subjects exhibited normalization of platelet parameters. In conclusion, mild abnormalities of platelet parameters were present not only in severe‐C but also, albeit to a lesser extent, in mild‐C patients during the acute phase of COVID‐19 and normalized in most tested patients after clinical recovery.
Prevalence of anti-platelet factor 4 antibodies in healthy vaccinees with adenoviral vector vaccines—A systematic review and meta-analysis
Bianca Clerici, Mariangela Scavone, Simone Birocchi, Chiara Aloise, Benedetta Peroni, Alessandra Negrini, Claudia Ghali, Giovanni Casazza, Gian Marco Podda
British Journal of Haematology, 2023
Cases of thrombocytopenia and thrombosis have been reported following vaccination with COVID-19 adenoviral vector vaccines, Ad26.COV.2 and ChAdOx1 nCoV-19.1-3 The condition, termed vaccine-induced immune thrombotic thrombocytopenia (VITT),4 is caused by antibodies against platelet factor 4 (PF4) bound to platelets.5 VITT strongly mimics auto-immune heparin-induced thrombocytopenia (aHIT).6 Thus, the HIT diagnostic algorithm, based on anti-PF4 enzyme-linked immunosorbent assays (ELISAs) as screening tests and on platelet activation assays (PAAs) as confirmation tests, has been applied to VITT.1, 2, 4 PF4-ELISAs are enzyme immunoassays designed to detect serum immunoglobulin G (IgG) or IgG/A/M anti-PF4 antibodies. PAAs can ascertain whether detected anti-PF4 antibodies display platelet-activating properties by exploring the capacity of patient serum to induce platelet aggregation.7 Since the very first descriptions of VITT, it has been proposed to optimize PAAs by adding exogenous PF4 (PF4-PAAs).1 Anti-PF4 antibodies have been reported in as many as 6.6% of healthy blood donors8 and in up to 50% of inpatients exposed to heparin.9-11 Whether the prevalence of anti-PF4 antibodies in healthy subjects with adenoviral vector vaccines is comparable to that of unvaccinated individuals is currently unknown. Here we report the results of a systematic review and meta-analysis of the prevalence of anti-PF4 antibodies in these subjects. PubMed and Embase were searched by Chiara Aloise and Benedetta Peroni with a pre-defined research string (see Data S1). Our research was restricted to articles written in English and published from 1 January 2020, until 31 July 2022. We evaluated: (i) VITT case reports and case series providing details on performed laboratory tests; (ii) studies investigating anti-PF4 antibodies in vaccinees with an adenoviral vector vaccine with no signs or symptoms of VITT; and (iii) laboratory studies investigating novel diagnostic tests and/or comparing different available diagnostic tests. We included only studies on vaccinees and laboratory studies that included vaccinees, and excluded studies or single patients of eligible studies if: (i) details on test methods were absent, scarce or unclear; or (ii) test results were unclear. Eligibility assessment was performed at title and/or abstract level by Chiara Aloise and Benedetta Peroni, who independently assessed each study. Disagreements were solved by consensus or by a third reviewer (Simone Birocchi). Performed diagnostic tests were categorized according to brand (PF4-ELISAs) and type (PAAs and PF4-PAAs). We only recorded results of diagnostic tests performed at least five times. For each study, we calculated the prevalence of anti-PF4 antibodies with their 95% confidence intervals (CI) using the exact binomial method. Further details on statistical analysis can be found in Data S1. We retrieved 2157 citations. After the exclusion of duplicates (n = 886) and ineligible studies (n = 1264), seven studies were included (Figure S1, full references in Data S1). Six out of seven eligible studies were observational clinical studies designed to determine the frequency of anti-PF4 antibodies in healthy vaccinees. Healthy vaccinees served as controls in a VITT case series by Althaus et al.12 The diagnostic tests performed in each study are shown in Table S1. The seven retrieved studies provided results of 3149 PF4-ELISAs, 22 PAAs and 16 PF4-PAAs, performed on a total of 3149 healthy vaccinees. Anti-PF4 antibodies were assayed with a PF4-ELISA in all eligible studies. In five out of seven eligible studies, PAAs and/or PF4-PAAs followed positive PF4-ELISAs. Table 1 shows PF4-ELISA results. Overall, the prevalence of anti-PF4 antibodies with PF4-ELISAs was relatively low (3.7%, 95% CI 2.1%–5.6%), and the optical densities (ODs) of all but one positive result were below 2.0. Table 2 shows PAA and PF4-PAA results. The prevalence of platelet-activating anti-PF4 antibodies detected by PAAs was 0% (95% CI, 0%–15.4%), with wide confidence intervals reflecting the paucity of tested subjects (n = 22). The prevalence of platelet-activating anti-PF4 antibodies detected by PF4-PAAs [n = 16, all tested with heparin-induced platelet activation (HIPA)] was 0% (95% CI, 0%–20.6%). Our systematic review and meta-analysis shows that the prevalence estimates of anti-PF4 antibodies detected by PF4-ELISA in healthy vaccinees (3.7%, 95% CI 2.1%–5.6%) is low and comparable to the reported frequency in healthy blood donors (6.6%, 95% CI 5.8%–7.4%).8 The positivity of potentially pathogenic auto-antibodies is a common finding in healthy subjects. In the setting of VITT, PAAs can help identify pathogenic anti-PF4 antibodies. In our systematic review, none of the anti-PF4 antibodies detected by ELISA displayed platelet-activating properties. In addition, whereas most VITT cases have PF4-ELISA ODs >2.0,4 ODs in healthy vaccinees were below 2.0 in 91 out of 92 positive results (99.0%). Despite the low number of tested subjects, our results point towards high PAA and PF4-PAA specificity, which supports their use as confirmation tests, where feasible. It is likely that PF4-ELISA positive results merely represent the consequence of seroconversion following vaccination or, perhaps more likely, reflect a pre-existing condition, considering that their prevalence is similar to that of blood donors.8 The calculated prevalence was lower than that in acutely ill patients exposed to heparin in whom HIT had been ruled out, which reaches 16.9% in patients with sepsis11 and 50% during or after cardiac surgery.9 Our findings are important in light of the uncertain duration of the COVID-19 pandemic, with many developing countries using mainly adenoviral vector vaccines due to their favourable storage profile,13 and of the prospective employment of this vaccine technology for communicable diseases other than COVID-19. Laboratory test results from healthy vaccinees point to a high specificity of VITT diagnostic tests and might be useful for the future implementation of evidence-based surveillance programs. This study has some limitations. Firstly, due to the small rate of seroconversion in healthy vaccinees, few PAAs and PF4-PAAs were performed, resulting in wide estimate CIs. In addition, the possibility of false negatives results obtained with PAAs and PF4-PAAs cannot be excluded. Moreover, in observational studies designed to determine the frequency of anti-PF4 antibodies in healthy vaccinees there was no declared clinicopathologic definition for the identification of VITT cases with the exception of the study by Uzun et al.14 In conclusion, our results show that the prevalence of anti-PF4 antibodies detected by PF4-ELISAs in healthy vaccinees is low and comparable to that of the general unvaccinated population; detected anti-PF4 antibodies did not activate platelets. Thus, our data support current VITT diagnostic strategies. Gian Marco Podda and Simone Birocchi designed the study, supervised data collection and analysis and critically revised the manuscript. Bianca Clerici wrote the manuscript and participated in study design, data extraction and analysis. Mariangela Scavone contributed to manuscript writing, data extraction and analysis and critically reviewed the intellectual content. Benedetta Peroni and Chiara Aloise performed the literature search under the supervision of Simone Birocchi. Benedetta Peroni, Chiara Aloise, Claudia Ghali and Alessandra Negrini performed data extraction and contributed to data analysis. Tables and Figures were prepared by Bianca Clerici, Mariangela Scavone, Benedetta Peroni, Chiara Aloise and Alessandra Negrini. Giovanni Casazza supervised the statistical approach and critically reviewed the manuscript. We thank professor Marco Cattaneo for critically reviewing the manuscript. This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Nothing to declare. Figure S1. Table S1. Data S1. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Platelet activation and modulation in thrombosis with thrombocytopenia syndrome associated with ChAdOx1 nCov-19 vaccine
Mariangela Scavone, Bianca Clerici, Simone Birocchi, Tatiana Mencarini, Mariagrazia Calogiuri, Claudia Ghali, Daniele Prati, Silvia Bozzi, Paolo Villa, Marco Cattaneo, Gian Marco Podda
Haematologica, 2021
Not available.