Immunogenicity and Safety of the BNT162b2 COVID-19 Vaccine in Patients with Cystic Fibrosis with or without Lung Transplantation.

Cystic fibrosis (CF) is characterized by a progressive decline in lung function, which may be further impaired by viral infections. CF is therefore considered a comorbidity of coronavirus disease 2019 (COVID-19), and SARS-CoV-2 vaccine prioritization has been proposed for patients with (pw)CF. Poor outcomes have been reported in lung transplant recipients (LTR) after SARS-CoV-2 infections. LTR have also displayed poor immunization against SARS-CoV-2 after mRNA-based BNT162b2 vaccination, especially in those undergoing immunosuppressive treatment, mostly those receiving mycophenolate mofetil (MMF) therapy. We aimed to determine here the immunogenicity and safety of the BNT162b2 vaccine in our cohort of 260 pwCF, including 18 LTR. Serum levels of neutralizing anti-SARS-CoV-2 IgG and IgA antibodies were quantified after the administration of two doses. PwCF displayed a vaccine-induced IgG and IgA antiviral response comparable with that seen in the general population. We also observed that the immunogenicity of the BNT162b2 vaccine was significantly impaired in the LTR subcohort, especially in patients undergoing MMF therapy. The BNT162b2 vaccine also caused minor adverse events as in the general population, mostly after administration of the second dose. Overall, our results justify the use of the BNT162b2 vaccine in pwCF and highlight the importance of a longitudinal assessment of the anti-SARS-CoV-2 IgG and IgA neutralizing antibody response to COVID-19 vaccination.

Plasma Bile Acid Profiling and Modulation of Secreted Mucin 5AC in Cholangiocarcinoma.

Studies investigating the potential role of circulating bile acids (BAs) as diagnostic biomarkers for cholangiocarcinoma (CCA) are sparse and existing data do not adjust for confounding variables. Furthermore, the mechanism by which BAs affect the expression of the oncogenic mucin 5AC (MUC5AC) has never been investigated. We performed a case-control study to characterise the profile of circulating BAs in patients with CCA (n = 68) and benign biliary disease (BBD, n = 48) with a validated liquid chromatography-tandem mass spectrometry technique. Odd ratios (OR) for CCA associations were calculated with multivariable logistic regression models based on a directed acyclic graph structure learning algorithm. The most promising BAs were then tested in an in vitro study to investigate their interplay in modulating MUC5AC expression. The total concentration of BAs was markedly higher in patients with CCA compared with BBD controls and accompanied by a shift in BAs profile toward a higher proportion of primary conjugated BAs (OR = 1.50, CI: 1.14 to 1.96, p = 0.003), especially taurochenodeoxycholic acid (TCDCA, OR = 42.29, CI: 3.54 to 504.63, p = 0.003) after multiple adjustments. Western blot analysis of secreted MUC5AC in human primary cholangiocytes treated with primary conjugated BAs or with TCDCA alone allowed us to identify a novel 230 kDa isoform, possibly representing a post-translationally modified MUC5AC specie.

Comprehensive assessment of humoral response after Pfizer BNT162b2 mRNA Covid-19 vaccination: a three-case series.

OBJECTIVES: Since universal vaccination is a pillar against coronavirus disease 2019 (COVID-19), monitoring anti-SARS-CoV-2 neutralizing antibodies is essential for deciphering post-vaccination immune response. METHODS: Three healthcare workers received 30 µg BNT162b2 mRNA Covid-19 Pfizer Vaccine, followed by a second identical dose, 21 days afterwards. Venous blood was drawn at baseline and at serial intervals, up to 63 days afterwards, for assessing total immunoglobulins (Ig) anti-RBD (receptor binding domain), anti-S1/S2 and anti-RBD IgG, anti-RBD and anti-N/S1 IgM, and anti-S1 IgA. RESULTS: All subjects were SARS-CoV-2 seronegative at baseline. Total Ig anti-RBD, anti-S1/S2 and anti-RBD IgG levels increased between 91 and 368 folds until 21 days after the first vaccine dose, then reached a plateau. The levels raised further after the second dose (by ∼30-, ∼8- and ∼8-fold, respectively), peaking at day 35, but then slightly declining and stabilizing ∼50 days after the first vaccine dose. Anti-S1 IgA levels increased between 7 and 11 days after the first dose, slightly declined before the second dose, after which levels augmented by ∼24-fold from baseline. The anti-RBD and anti-N/S1 IgM kinetics were similar to that of anti-S1 IgA, though displaying substantially weaker increases and modest peaks, only 4- to 7-fold higher than baseline. Highly significant inter-correlation was noted between total Ig anti-RBD, anti-S1/S2 and anti-RBD IgG (all r=0.99), whilst other anti-SARS-CoV-2 antibodies displayed lower, though still significant, correlations. Serum spike protein concentration was undetectable at all-time points. CONCLUSIONS: BNT162b2 mRNA vaccination generates a robust humoral immune response, especially involving anti-SARS-Cov-2 IgG and IgA, magnified by the second vaccine dose.

Diagnostic Accuracy of a Rapid SARS-CoV-2 Antigen Test Among People Experiencing Homelessness: A Prospective Cohort and Implementation Study.

INTRODUCTION: Detection strategies in vulnerable populations such as people experiencing homelessness (PEH) need to be explored to promptly recognize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks. This study investigated the diagnostic accuracy of a rapid SARS-CoV-2 Ag test in PEH during two pandemic waves compared with gold standard real-time multiplex reverse transcription polymerase chain reaction (rtRT-PCR). METHODS: All PEH ≥ 18 years requesting residence at the available shelters in Verona, Italy, across two cold-weather emergency periods (November 2020-May 2021 and December 2021-April 2022) were prospectively screened for SARS-CoV-2 infection by means of a naso-pharyingeal swab. A lateral flow immunochromatographic assay (Biocredit® COVID-19 Ag) was used as antigen-detecting rapid diagnostic test (Ag-RDT). The rtRT-PCR was performed with Allplex™ SARS-CoV-2 assay kit (Seegene). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated as measures for diagnostic accuracy. RESULTS: Overall, 503 participants were enrolled during the two intervention periods for a total of 732 paired swabs collected: 541 swabs in the first period and 191 in the second. No significant differences in demographic and infection-related characteristics were observed in tested subjects in the study periods, except for the rate of previous infection (0.8% versus 8%; p < 0.001) and vaccination (6% versus 73%; p < 0.001). The prevalence of SARS-CoV-2 in the cohort was 8% (58/732 swabs positive with rtRT-PCR). Seventeen swabs were collected from symptomatic patients (7%). Among them, the concordance between rtRT-PCR and Ag-RDT was 100%, 7 (41.2%) positive and 10 negative pairs. The overall sensitivity of Ag-RDT was 63.8% (95% CI 60.3-67.3) and specificity was 99.8% (95% CI 99.6-100). PPV and NPV were 97.5% and 96.8%, respectively. Sensitivity and specificity did not change substantially across the two periods (65.1% and 99.8% in 2020-2021 vs. 60% and 100% in 2021-2022). CONCLUSIONS: A periodic Ag-RDT-based screening approach for PEH at point of care could guide preventive measures, including prompt isolation, without referral to hospital-based laboratories for molecular test confirmation in case of positive detection even in individuals asymptomatic for COVID-19. This could help reduce the risk of outbreaks in shelter facilities.

Host immunological responses facilitate development of SARS-CoV-2 mutations in patients receiving monoclonal antibody treatments.

BackgroundThe role of host immunity in emergence of evasive SARS-CoV-2 Spike mutations under therapeutic monoclonal antibody (mAb) pressure remains to be explored.MethodsIn a prospective, observational, monocentric ORCHESTRA cohort study, conducted between March 2021 and November 2022, mild-to-moderately ill COVID-19 patients (n = 204) receiving bamlanivimab, bamlanivimab/etesevimab, casirivimab/imdevimab, or sotrovimab were longitudinally studied over 28 days for viral loads, de novo Spike mutations, mAb kinetics, seroneutralization against infecting variants of concern, and T cell immunity. Additionally, a machine learning-based circulating immune-related biomarker (CIB) profile predictive of evasive Spike mutations was constructed and confirmed in an independent data set (n = 19) that included patients receiving sotrovimab or tixagevimab/cilgavimab.ResultsPatients treated with various mAbs developed evasive Spike mutations with remarkable speed and high specificity to the targeted mAb-binding sites. Immunocompromised patients receiving mAb therapy not only continued to display significantly higher viral loads, but also showed higher likelihood of developing de novo Spike mutations. Development of escape mutants also strongly correlated with neutralizing capacity of the therapeutic mAbs and T cell immunity, suggesting immune pressure as an important driver of escape mutations. Lastly, we showed that an antiinflammatory and healing-promoting host milieu facilitates Spike mutations, where 4 CIBs identified patients at high risk of developing escape mutations against therapeutic mAbs with high accuracy.ConclusionsOur data demonstrate that host-driven immune and nonimmune responses are essential for development of mutant SARS-CoV-2. These data also support point-of-care decision making in reducing the risk of mAb treatment failure and improving mitigation strategies for possible dissemination of escape SARS-CoV-2 mutants.FundingThe ORCHESTRA project/European Union's Horizon 2020 research and innovation program.

Plasma Bile Acid Profile in Patients with and without Type 2 Diabetes.

A paucity of information currently exists on plasma bile acid (BA) profiles in patients with and without type 2 diabetes mellitus (T2DM). We assayed 14 plasma BA species in 224 patients with T2DM and in 102 nondiabetic individuals with metabolic syndrome. Plasma BA levels were measured with ultra-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) technique. Multivariable linear regression analyses were undertaken to assess associations between measured plasma BA species and T2DM status after adjustment for confounding factors. The presence of T2DM was significantly associated with higher plasma concentrations of both primary BAs (adjusted-standardized ß coefficient: 0.279, p = 0.005) and secondary BAs (standardized ß coefficient: 0.508, p < 0.001) after adjustment for age, sex, adiposity measures, serum alanine aminotransferase and use of statins or metformin. More specifically, the presence of T2DM was significantly associated with higher levels of plasma taurochenodeoxycholic acid, taurodeoxycholic acid, glycochenodeoxycholic acid, hyodeoxycholic acid, glycodeoxycholic acid, glycolithocholic acid, deoxycholic acid, taurochenodeoxycholic acid, taurodeoxycholic acid, glycochenodeoxycholic acid and glycodeoxycholic acid (adjusted-standardized ß coefficients ranging from 0.315 to 0.600; p < 0.01 or less), as well as with lower plasma levels of cholic acid (adjusted-standardized ß coefficient: -0.250, p = 0.013) and taurocholic acid (adjusted-standardized ß coefficient: -0.309, p = 0.001). This study shows that there are marked differences in plasma BA profiles between patients with and without T2DM. Further research will be needed to better understand how these differences in plasma BA profiles may interplay with the pathophysiology of T2DM.

Comparison of five commercial anti-SARS-CoV-2 total antibodies and IgG immunoassays after vaccination with BNT162b2 mRNA.

BACKGROUND: Since universal vaccinations represents the most effective strategy to mitigate coronavirus disease 2019 (COVID-19), baseline assessment and post-vaccine monitoring of anti-SARS-CoV-2 neutralizing antibodies are essential to vaccination programs. Therefore, this study aimed to compare data of five commercial anti-SARS-CoV2 immunoassays after administration of an mRNA vaccine. METHODS: Venous blood was collected from three healthcare workers, receiving a double (30 g) dose of BNT162b2 mRNA Covid-19 vaccine (Comirnaty, Pfizer), on the day of the first vaccine dose and then at fixed intervals for the following 2 months. Anti-SARS-CoV-2 neutralizing antibody response was assayed with Roche Total Ig anti-RBD (receptor binding domain), DiaSorin TrimericS IgG (spike trimer), Beckman Coulter IgG anti-RBD, SNIBE IgG anti-RBD and Technogenetics IgG anti-N/S1. RESULTS: A total number of 45 samples were drawn at the end of the 2-month study period. The Spearman's correlations of absolute anti-SARS-CoV-2 antibodies were always excellent (all p<0.001), comprised between 0.967-0.994. Satisfactory results were also observed when absolute antiSARS-CoV-2 antibodies values of the five methods were compared with the mean consensus value, with correlations always higher than 0.979 (all p<0.001). The agreement of anti-SARS-CoV-2 antibodies positivity versus the consensus median positivity ranged between 0.764 and 1.000 (always p<0.001), but become always >0.900 after readjustment of one assay cutoff. CONCLUSIONS: All the immunoassays evaluated in this study appear suitable for monitoring anti-SARS-CoV-2 neutralizing antibodies response in subjects undergoing mRNA COVID-19 vaccination.

SARS-CoV-2 Infection in Health Workers: Analysis from Verona SIEROEPID Study during the Pre-Vaccination Era.

BACKGROUND: To report the baseline phase of the SIEROEPID study on SARS-CoV-2 infection seroprevalence among health workers at the University Hospital of Verona, Italy, between spring and fall 2020; to compare performances of several laboratory tests for SARS-CoV-2 antibody detection. METHODS: 5299 voluntary health workers were enrolled from 28 April 2020 to 28 July 2020 to assess immunological response to SARS-CoV-2 infection throughout IgM, IgG and IgA serum levels titration by four laboratory tests. Association of antibody titre with several demographic variables, swab tests and performance tests (sensitivity, specificity, and agreement) were statistically analyzed. RESULTS: The overall seroprevalence was 6%, considering either IgG and IgM, and 4.8% considering IgG. Working in COVID-19 Units was not associated with a statistically significant increase in the number of infected workers. Cohen's kappa of agreement between MaglumiTM and VivaDiagTM was quite good when considering IgG only (Cohen's kappa = 78.1%, 95% CI 74.0-82.0%), but was lower considering IgM (Cohen's kappa = 13.3%, 95% CI 7.8-18.7%). CONCLUSION: The large sample size with high participation (84.7%), the biobank and the longitudinal design were significant achievements, offering a baseline dataset as the benchmark for risk assessment, health surveillance and management of SARS-CoV-2 infection for the hospital workforce, especially considering the ongoing vaccination campaign. Study results support the national regulator guidelines on using swabs for SARS-CoV-2 screening with health workers and using the serological tests to contribute to the epidemiological assessment of the spread of the virus.

Ezetimibe Prevents Ischemia/Reperfusion-Induced Oxidative Stress and Up-Regulates Nrf2/ARE and UPR Signaling Pathways.

BACKGROUND: While reperfusion is crucial for survival after an episode of ischemia, it also causes oxidative stress. Nuclear factor-E2-related factor 2 (Nrf2) and unfolded protein response (UPR) are protective against oxidative stress and endoplasmic reticulum (ER) stress. Ezetimibe, a cholesterol absorption inhibitor, has been shown to activate the AMP-activated protein kinase (AMPK)/Nrf2 pathway. In this study we evaluated whether Ezetimibe affects oxidative stress and Nrf2 and UPR gene expression in cellular models of ischemia-reperfusion (IR). METHODS: Cultured cells were subjected to simulated IR with or without Ezetimibe. RESULTS: IR significantly increased reactive oxygen species (ROS) production and the percentage of apoptotic cells without the up-regulation of Nrf2, of the related antioxidant response element (ARE) gene expression or of the pro-survival UPR activating transcription factor 6 (ATF6) gene, whereas it significantly increased the pro-apoptotic CCAAT-enhancer-binding protein homologous protein (CHOP). Ezetimibe significantly decreased the cellular ROS formation and apoptosis induced by IR. These effects were paralleled by the up-regulation of Nrf2/ARE and ATF6 gene expression and by a down-regulation of CHOP. We also found that Nrf2 activation was dependent on AMPK, since Compound C, a pan inhibitor of p-AMPK, blunted the activation of Nrf2. CONCLUSIONS: Ezetimibe counteracts IR-induced oxidative stress and induces Nrf2 and UPR pathway activation.

Physical Exercise Reduces Cytotoxicity and Up-Regulates Nrf2 and UPR Expression in Circulating Cells of Peripheral Artery Disease Patients: An Hypoxic Adaptation?

AIM: Ischemia-reperfusion (I-R) produces reactive oxygen species (ROS) that damage cells and favour cytotoxicity and apoptosis in peripheral artery disease (PAD) patients. Since brief episodes of I-R (ischemic conditioning) protect cells against ischemic harms, we evaluated whether a short-course of supervised treadmill training, characterized by repeated episodes of I-R, makes peripheral blood mononuclear cells (PBMCs) from PAD patients with intermittent claudication more resistant to I-R injuries by reducing oxidative stress and by inducing an adaptative response of unfolded protein response (UPR) and nuclear factor-E2-related factor (Nrf2) pathway expression. METHODS: 24 PAD patients underwent 21 sessions of treadmill training and a treadmill test as indicator of acute response to I-R. RESULTS: Maximal and pain free walking distance improved (p＜0.01), whereas LDH leakage and apoptosis of PBMCs decreased (p＜0.01); plasma malondialdehyde and ROS generation in PBMCs declined, while plasma glutathione augmented (p＜0.01). Moreover we demonstrated an up-regulation of UPR and Nrf2 expression in PBMCs (p＜0.01). To understand whether treadmill training may act as a trigger of ischemic conditioning, we examined the effect of repeated episodes of I-R on adaptative response in PBMCs derived from the patients. We showed an up-regulation of UPR and Nrf2 gene expression (p＜0.01), while oxidative stress and cytotoxicity, after an initial increase, declined (p＜0.01). This positive effect on cytotoxicity was reduced after inhibition of UPR and Nrf2 pathways. CONCLUSIONS: Treadmill training in PAD patients through UPR and Nrf2 up-regulation may trigger hypoxic adaptation similar to conditioning, thus modifying cell survival.

Ratiometric sweat secretion optical test in cystic fibrosis, carriers and healthy subjects.

We have simplified the published procedure (5) for measuring sweat rates in individual human sweat glands. Sweat secretion rates were obtained from sweat drops secreted on the forearm by multiple individual glands. We computed a ratio between CFTR-dependent (by intradermal microinjection of a ß adrenergic cocktail) and CFTR-independent (by methacoline as cholinergic stimulus) sweat secretion rates. We obtained a reproducible, approximately linear readout of CFTR function with measurements performed by two different independent teams. We considered three groups (CF subjects, CF carriers and non-CF controls, n=22 in each group); their mean ratios was respectively 0.000, 0.104 and 0.205 The average ratio of CF subjects was consistent with diagnosis in 3 additional cases clinically resembling CF. All groups were clearly discriminated, with sensibility and specificity ranging from 82% to 100%. A software was developed for detecting sweat droplets. This bioassay is suitabile for multicentre studies focusing on CFTR targeted therapies, controversial diagnosis and functional relevance of rare CFTR mutations.

Generation of mesenchymal stromal cells from cord blood: evaluation of in vitro quality parameters prior to clinical use.

BACKGROUND: Increasing evidence suggests the safety and efficacy of mesenchymal stromal cells (MSC) as advanced therapy medicinal products because of their immunomodulatory properties and supportive role in hematopoiesis. Although bone marrow remains the most common source for obtaining off-the-shelf MSC, cord blood (CB) represents an alternative source, which can be collected noninvasively and without major ethical concerns. However, the low estimated frequency and inconsistency of successful isolation represent open challenges for the use of CB-derived MSC in clinical trials. This study explores whether CB may represent a suitable source of MSC for clinical use and analyzes several in vitro parameters useful to better define the quality of CB-derived MSC prior to clinical application. METHODS: CB units (n = 50) selected according to quality criteria (CB volume ≥ 20 ml, time from collection ≤ 24 h) were cultured using a standardized procedure for CB-MSC generation. MSC were analyzed for their growth potential and secondary colony-forming capacity. Immunophenotype and multilineage differentiation potential of culture-expanded CB-MSC were assessed to verify MSC identity. The immunomodulatory activity at resting conditions and after inflammatory priming (IFN-γ-1b and TNF-α for 48 hours) was explored to assess the in vitro potency of CB-MSC prior to clinical application. Molecular karyotyping was used to assess the genetic stability after prolonged MSC expansion. RESULTS: We were able to isolate MSC colonies from 44% of the processed units. Our results do not support a role of CB volume in determining the outcome of the cultures, in terms of both isolation and proliferative capacity of CB-MSC. Particularly, we have confirmed the existence of two different CB-MSC populations named short- and long-living (SL- and LL-) CBMSC, clearly diverging in their growth capacity and secondary colony-forming efficiency. Only LL-CBMSC were able to expand consistently and to survive for longer periods in vitro, while preserving genetic stability. Therefore, they may represent interesting candidates for therapeutic applications. We have also observed that LL-CBMSC were not equally immunosuppressive, particularly after inflammatory priming and despite upregulating priming-inducible markers. CONCLUSIONS: This work supports the use of CB as a potential MSC source for clinical applications, remaining more readily available compared to conventional sources. We have provided evidence that not all LL-CBMSC are equally immunosuppressive in an inflammatory environment, suggesting the need to include the assessment of potency among the release criteria for each CB-MSC batch intended for clinical use, at least for the treatment of immune disorders as GvHD.