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1.
Biosensors ; 13(1):43, 2023.
Article in English | MDPI | ID: covidwho-2166246

ABSTRACT

In this work, we report on the development of a simple electrochemical immunosensor for the detection of D-dimer protein in human plasma samples. The immunosensor is built by a simple drop-casting procedure of chitosan nanoparticles (CSNPs) as biocompatible support, Protein A (PrA), to facilitate the proper orientation of the antibody sites to epitopes as a capture biomolecule, and the D-dimer antibody onto a carboxyl functionalized multi-walled carbon nanotubes screen printed electrode (MWCNTs-SPE). The CSNPs have been morphologically characterized by Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS) techniques. Successively, the electrochemical properties of the screen-printed working electrode after each modification step have been characterized by differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The resulting MWCNTs-CSNPs-PrA-D-dimer Ab immunosensor displays an optimal and promising platform for antibody immobilization and specific D-dimer detection. DPV has been used to investigate the antigen/antibody interaction at different D-dimer concentrations. The proposed voltammetric immunosensor allowed a linear range from 2 to 500 μg L-1 with a LOD of 0.6 μg L-1 and a sensitivity of 1.3 μA L μg-1 cm-2. Good stability and a fast response time (5 s) have been reported. Lastly, the performance of the voltammetric immunosensor has been tested in human plasma samples, showing satisfactory results, thus attesting to the promising feasibility of the proposed platform for detecting D-dimer in physiological samples.

2.
Front Public Health ; 10: 1010130, 2022.
Article in English | MEDLINE | ID: covidwho-2142344

ABSTRACT

Background: To safely resume in-person activities during the COVID-19 pandemic, Sapienza University of Rome implemented rigorous infection prevention and control measures, a successful communication campaign and a free SARS-CoV-2 testing program. In this study, we describe the University's experience in carrying out such a program in the context of the COVID-19 response and identify risk factors for infection. Methods: Having identified resources, space, supplies and staff, from March to June 2021 Sapienza offered to all its enrollees a molecular test service (8.30 AM to 4 PM, Monday to Thursday). A test-negative case-control study was conducted within the program. Participants underwent structured interviews that investigated activity-related exposures in the 2 weeks before testing. Multivariable conditional logistic regression analyses were performed. Adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) were calculated. Results: A total of 8,959 tests were administered, of which 56 were positive. The detection trend followed regional tendencies. Among 40 cases and 80 controls, multivariable analysis showed that a known exposure to a COVID-19 case increased the likelihood of infection (aOR: 8.39, 95% CI: 2.38-29.54), while having a job decreased it (aOR: 0.23, 95% CI: 0.06-0.88). Of factors that almost reached statistical significance, participation in activities in the university tended to reduce the risk (aOR: 0.32, 95% CI: 0.09-1.06), while attendance at private gatherings showed an increasing risk trend (aOR: 3.48, 95% CI: 0.95-12.79). Age, gender, activities in the community, visiting bars or restaurants, and use of public transportation were not relevant risk factors. When those students regularly attending the university campus were excluded from the analysis, the results were comparable, except that attending activities in the community came close to having a statistically significant effect (aOR: 8.13, 95% CI: 0.91-72.84). Conclusions: The testing program helped create a safe university environment. Furthermore, promoting preventive behavior and implementing rigorous measures in public places, as was the case in the university setting, contributed to limit the virus transmission.


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , SARS-CoV-2 , Pandemics/prevention & control , COVID-19 Testing , Prevalence , Case-Control Studies
3.
Clin Exp Med ; 2022 Nov 16.
Article in English | MEDLINE | ID: covidwho-2117299

ABSTRACT

The immune response to the SARS-CoV-2 infection is crucial to the patient outcome. IL-18 is involved in the lymphocyte response to the disease and it is well established its important role in the complex developing of the host response to viral infection. This study aims at the analysis of the concentrations of IL-18, IL-18BP, INF-γ at the onset of the SARS-CoV-2 infection. The serum levels of measured interleukins were obtained through enzyme-linked immunosorbent assay. Furthermore, the free fraction of IL-18 was numerically evaluated. The enrolled patients were divided in two severity groups according to a threshold value of 300 for the ratio of arterial partial pressure of oxygen and fraction of inspired oxygen fraction and according to the parenchymal involvement as evaluated by computerized tomography at the admittance. In the group of patients with a more severe disease, a significant increase of the IL-18, INF-γ and IL-18BP levels have been observed, whereas the free IL-18 component values were almost constant. The results confirm that, at the onset of the disease, the host response keep the inflammatory cytokines in an equilibrium and support the hypothesis to adopt the IL-18BP modulation as a possible and effective therapeutic approach.

4.
Frontiers in public health ; 10, 2022.
Article in English | EuropePMC | ID: covidwho-2101589

ABSTRACT

Background To safely resume in-person activities during the COVID-19 pandemic, Sapienza University of Rome implemented rigorous infection prevention and control measures, a successful communication campaign and a free SARS-CoV-2 testing program. In this study, we describe the University's experience in carrying out such a program in the context of the COVID-19 response and identify risk factors for infection. Methods Having identified resources, space, supplies and staff, from March to June 2021 Sapienza offered to all its enrollees a molecular test service (8.30 AM to 4 PM, Monday to Thursday). A test-negative case-control study was conducted within the program. Participants underwent structured interviews that investigated activity-related exposures in the 2 weeks before testing. Multivariable conditional logistic regression analyses were performed. Adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) were calculated. Results A total of 8,959 tests were administered, of which 56 were positive. The detection trend followed regional tendencies. Among 40 cases and 80 controls, multivariable analysis showed that a known exposure to a COVID-19 case increased the likelihood of infection (aOR: 8.39, 95% CI: 2.38–29.54), while having a job decreased it (aOR: 0.23, 95% CI: 0.06–0.88). Of factors that almost reached statistical significance, participation in activities in the university tended to reduce the risk (aOR: 0.32, 95% CI: 0.09–1.06), while attendance at private gatherings showed an increasing risk trend (aOR: 3.48, 95% CI: 0.95–12.79). Age, gender, activities in the community, visiting bars or restaurants, and use of public transportation were not relevant risk factors. When those students regularly attending the university campus were excluded from the analysis, the results were comparable, except that attending activities in the community came close to having a statistically significant effect (aOR: 8.13, 95% CI: 0.91–72.84). Conclusions The testing program helped create a safe university environment. Furthermore, promoting preventive behavior and implementing rigorous measures in public places, as was the case in the university setting, contributed to limit the virus transmission.

5.
Biomedicines ; 10(10)2022 Sep 29.
Article in English | MEDLINE | ID: covidwho-2065695

ABSTRACT

The waning effectiveness of the primary vaccination for SARS-CoV-2 led to administration of an additional booster dose (BD). The efficacy of the BD in stimulating humoral systemic immune response is well established, but its effectiveness on inducing mucosal immune reaction has not yet been reported. To address this issue, we evaluated SARS-CoV-2-specific antibody responses in the serum, saliva, and tears after BNT162b2 (Pfizer/BioNTech, New York, NY, USA) vaccination and BD, as well as after SARS-CoV-2 infection. After two doses of BNT162b2 vaccine, we observed specific serum IgG in 100% and IgA in 97.2% of subjects, associated with mucosal response in both salivary samples (sIgA in 97.2% and IgG(S) in 58.8%) and in tears (sIgA in 77.8% and IgG(S) in 67.7%). BD induced a recovery of the systemic humoral response and of tear sIgA when compared to 6 months of follow-up titers (p < 0.001; p = 0.012). However, sIgA levels in both tears and saliva were significantly lower following BD when compared to patients with prior SARS-CoV-2 infection (p = 0.001 and p = 0.005, respectively). Our results demonstrated that administration of BD restored high serum levels of both IgG and IgA but had a poor effect in stimulating mucosal immunity when compared to prior SARS-CoV-2 infection.

6.
Electroanalysis ; 2022 Sep 29.
Article in English | MEDLINE | ID: covidwho-2047543

ABSTRACT

Here, a novel biosensing platform for the detection of SARS-CoV-2 usable both at voltammetric and impedimetric mode is reported. The platform was constructed on a multi-walled carbon nanotubes (MWCNTs) screen-printed electrode (SPE) functionalized by methylene blue (MB), antibodies against SARS-CoV-2 spike protein (SP), a bioactive layer of chitosan (CS) and protein A (PrA). The voltammetric sensor showed superior performances both in phosphate buffer solution (PBS) and spiked-saliva samples, with LOD values of 5.0±0.1 and 30±2.1 ng/mL, compared to 20±1.8 and 50±2.5 ng/mL for the impedimetric sensor. Moreover, the voltammetric immunosensor was tested in real saliva, showing promising results.

7.
J Pers Med ; 12(6)2022 Jun 18.
Article in English | MEDLINE | ID: covidwho-1987865

ABSTRACT

Vaccine-induced immunity is a key strategy in the long-term control of the COVID-19 pandemic. The aim of our study was to explore the relationship between mRNA vaccine-induced antibodies and gender-sensitive variables among healthcare workers. Two thousand-sixty-five volunteers who received the BNT162b2 vaccine were enrolled in the study and followed up. Demographic, clinical, and social variables (educational level, marital status, occupation, childcare) were evaluated through a self-administered questionnaire. Anti-Spike (S) IgG were measured at 1 month (T1) and at 5 months (T2) after the second vaccine dose. At T1, median anti-S IgG values were 693 [394->800] AU/mL (1 AU = 2.6 BAU). Values > 800 AU/mL (2080 BAU/mL) were directly associated with a previous COVID-19 (p < 0.001) infection and inversely with age (p < 0.001), smoking habit (p < 0.001), and autoimmune diseases (p < 0.001). At T2, a significant decreasing in anti-S IgG values was observed (187 [81-262] AU/mL), with a median decrease of 72 [60-82]%. On multivariate data analysis, a reduction of more than 82% was directly associated with male sex (p < 0.021), age (p < 0.001), smoking (p = 0.038), hypertension (p = 0.042), and, inversely, with previous COVID-19 infection (p < 0.001) and being "cohabiting" (p = 0.005). Our findings suggest that demographic, clinical, and social variables play a role in anti-S IgG values decreasing in long-term follow up and should be considered to find personalized vaccine schedules.

8.
Eur J Immunol ; 52(7): 1120-1128, 2022 07.
Article in English | MEDLINE | ID: covidwho-1929799

ABSTRACT

A significant number of COVID-19 patients were shown to have neutralizing antibodies (NAB) against IFN; however, NAB specificity, fluctuation over time, associations with biochemical and hematological parameters, and IFN gene expression are not well characterized. Binding antibodies (BAB) to IFN-α/-ß were screened in COVID-19 patients' serum. All BAB positive sera, and a subset of respiratory samples, were tested for NAB against IFN-α/-ß/-ω, using an antiviral bioassay. Transcript levels of IFN-α/-ß/-ω and IFN-stimulated genes (ISGs) were quantified. Anti-IFN-I BAB were found in 61 out of 360 (17%) of patients. Among BAB positive sera, 21.3% had a high NAB titer against IFN-α. A total of 69.2% of anti-IFN-α NAB sera displayed cross-reactivity to IFN-ω. Anti-IFN-I NAB persisted in all patients. NAB to IFN-α were also detected in 3 out of 17 (17.6%) of respiratory samples. Anti-IFN-I NAB were higher in males (p = 0.0017), patients admitted to the ICU (p < 0.0001), and patients with a fatal outcome (p < 0.0001). NAB were associated with higher levels of CRP, LDH, d-Dimer, and higher counts of hematological parameters. ISG-mRNAs were reduced in patients with persistently NAB titer. NAB are detected in a significant proportion of severe COVID-19. NAB positive patients presented a defective IFN response and increased levels of laboratory biomarkers of disease severity.


Subject(s)
Antibodies, Neutralizing , COVID-19 , Biomarkers , Down-Regulation , Humans , Interferon-alpha , Interferon-beta , Male , Severity of Illness Index
9.
Radiol Med ; 127(7): 725-732, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1888998

ABSTRACT

PURPOSE: To correlate in COVID-19 pneumonia CT-based semi-quantitative score of pulmonary involvement with high serum levels of KL-6, a biomarker of disease severity. METHODS: Between March 28 to May 21, 2020, 196 patients with strong suspicion of SARS-CoV-2 were evaluated with RT-PCR for SARS-CoV-2, chest CT scan and blood test, including KL-6 serum protein, in our Emergency Unit. The final population included only patients who underwent blood sampling for KL-6 within 5 days from CT scan (n = 63), including n = 37 COVID-19-positive patients and n = 26 with negative RT-PCR testing for SARS-CoV-2 (control group). A semi-quantitative CT score was calculated based on the extent of lobar involvement (0:0%; 1, < 5%; 2:5-25%; 3:26-50%; 4:51-75%; 5, > 75%; range 0-5; global score 0-25). RESULTS: CT score was significantly correlated with serum value of KL-6 (r = 27, p = 0.035). This correlation was also present in COVID-19 positive patients (r = 0.423, p = 0.009) and CT score median value was significantly higher in patients with high KL-6 value (> 400 U/mL; 12.00, IQR 5.00-18.00, p-value 0.027). In control group, no statistically significant correlation was found between CT score and KL-6 value and CT score was higher in patients with high KL-6, although this difference was not statistically significant (5.00, IQR:1.75-8.00 versus 3.50, IQR:2.00-6.50). "Crazy paving" at the right upper (n = 8; 61.5%) and middle lobe (n = 4; 30.8%) and "consolidation" at the middle lobe (n=5; 38.5%) were observed in COVID-19 group with a significant difference between patients with high KL-6 value. CONCLUSION: CT score is highly correlated with KL-6 value in COVID-19 patients and might be beneficial to speed-up diagnostic workflow in symptomatic cases.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnostic imaging , Humans , Lung , Prognosis , Tomography, X-Ray Computed
11.
Microbes Infect ; 24(6-7): 104976, 2022 09.
Article in English | MEDLINE | ID: covidwho-1773645

ABSTRACT

One of the most urgent needs worldwide is to vaccinate against SARS-CoV-2 as many people as possible. We evaluated humoral response to Comirnaty vaccine in Thalassemia Major patients (TM). We measured SARS-CoV-2-specific antibodies against Spike protein in 57 TM patients and 58 healthy blood donors (HBD). TM and HBD subjects revealed a homogeneous serological response to the Comirnaty (Mean ± SD; TM = 1917,21 ± 1384,49; HBD = 2039,81 ± 1064,44; p = 0,5884). No statistically significant differences were observed among two groups. Interestingly, we observed in 73.3% of asplenic patients Ab-S titres above 800 BAU, whereas only in 26% of non splenectomized patients showed Ab-S titres above 800 BAU). This differences were statistically significant p < 0.039. Further measurement on other Ab types was needed for better understanding humoral response to Comirnaty.


Subject(s)
COVID-19 , Viral Vaccines , beta-Thalassemia , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , Humans , Immunity, Humoral , RNA, Viral , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Vaccination , Vaccines, Synthetic , mRNA Vaccines
12.
Vaccines (Basel) ; 10(1)2022 Jan 05.
Article in English | MEDLINE | ID: covidwho-1614029

ABSTRACT

Obesity is associated with a poor COVID-19 prognosis, and it seems associated with reduced humoral response to vaccination. Public health campaigns have advocated for weight loss in subjects with obesity, hoping to eliminate this risk. However, no evidence proves that weight loss leads to a better prognosis or a stronger immune response to vaccination. We aimed to investigate the impact of rapid weight loss on the adaptive immune response in subjects with morbid obesity. Twenty-one patients followed a hypocaloric, very-low-carbohydrate diet one week before to one week after the two mRNA vaccine doses. The diet's safety and efficacy were assessed, and the adaptive humoral (anti-SARS CoV-2 S antibodies, Abs) and cell-mediated responses (IFNγ secretion on stimulation with two different SARS CoV-2 peptide mixes, IFNγ-1 and IFNγ-2) were evaluated. The patients lost ~10% of their body weight with metabolic improvement. A high baseline BMI correlated with a poor immune response (R -0.558, p = 0.013 for IFNγ-1; R -0.581, p = 0.009 for IFNγ-2; R -0.512, p = 0.018 for Abs). Furthermore, there was a correlation between weight loss and higher IFNγ-2 (R 0.471, p = 0.042), and between blood glucose reduction and higher IFNγ-1 (R 0.534, p = 0.019), maintained after weight loss and waist circumference reduction adjustment. Urate reduction correlated with higher Abs (R 0.552, p = 0.033). In conclusion, obesity is associated with a reduced adaptive response to a COVID-19 mRNA vaccine, and weight loss and metabolic improvement may reverse the effect.

13.
Int J Environ Res Public Health ; 18(13)2021 06 24.
Article in English | MEDLINE | ID: covidwho-1389368

ABSTRACT

We read with great interest the paper by Gaudio and colleagues on vitamin D and on the state of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the time of admission [...].


Subject(s)
COVID-19 , SARS-CoV-2 , Hospitals , Humans , Public Health , Vitamin D
14.
Life (Basel) ; 11(7)2021 Jul 06.
Article in English | MEDLINE | ID: covidwho-1302363

ABSTRACT

Background. Health and social management of the SARS-CoV-2 epidemic, responsible for the COVID-19 disease, requires both screening tools and diagnostic procedures. Reliable screening tests aim at identifying (truely) infectious individuals that can spread the viral infection and therefore are essential for tracing and harnessing the epidemic diffusion. Instead, diagnostic tests should supplement clinical and radiological findings, thus helping in establishing the diagnosis. Several analytical assays, mostly using RT-PCR-based technologies, have become commercially available for healthcare workers and clinical laboratories. However, such tests showed some critical limitations, given that a relevant number of both false-positive and false-negative cases have been so far reported. Moreover, those analytical techniques demonstrated to be significantly influenced by pre-analytical biases, while the sensitivity showed a dramatic time dependency. Aim. Herein, we critically investigate limits and perspectives of currently available RT-PCR techniques, especially when referring to the required performances in providing reliable epidemiological and clinical information. Key Concepts. Current data cast doubt on the use of RT-PCR swabs as a screening procedure for tracing the evolution of the current SARS-COV-2 pandemic. Indeed, the huge number of both false-positive and false-negative results deprives the trustworthiness of decision making based on those data. Therefore, we should refine current available analytical tests to quickly identify individuals able to really transmit the virus, with the aim to control and prevent large outbreaks.

16.
Clin Case Rep ; 8(12): 3139-3142, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-796097

ABSTRACT

We think that thalassemia is not necessarily a cause of aggravation of the clinical course in COVID-19; however, certain key factors must be considered, such as the anemic condition, the likely pathogenic role of the virus on hemoglobin, and the hypercoagulable state to prevent any complications.

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