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1.
Antib Ther ; 5(3): 177-191, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1992090

ABSTRACT

Additional COVID-19 vaccines that are safe and immunogenic are needed for global vaccine equity. Here, we developed a recombinant type 5 adenovirus vector encoding for the SARS-CoV-2 S1 subunit antigen and nucleocapsid as a fusion protein (Ad5.SARS-CoV-2-S1N). A single subcutaneous immunization with Ad5.SARS-CoV-2-S1N induced a similar humoral response, along with a significantly higher S1-specific cellular response, as a recombinant type 5 adenovirus vector encoding for S1 alone (Ad5.SARS-CoV-2-S1). Immunogenicity was improved by homologous prime-boost vaccination, and further improved through intramuscular heterologous prime-boost vaccination using subunit recombinant S1 protein. Priming with low dose (1 × 1010 v.p.) of Ad5.SARS-CoV-2-S1N and boosting with either wild-type recombinant rS1 or B.1.351 recombinant rS1 induced a robust neutralizing response, which was sustained against Beta and Gamma SARS-CoV-2 variants. This novel Ad5-vectored SARS-CoV-2 vaccine candidate showed promising immunogenicity in mice and supports the further development of COVID-19-based vaccines incorporating the nucleoprotein as a target antigen.

2.
Biomedicines ; 10(8):1993, 2022.
Article in English | MDPI | ID: covidwho-1987652

ABSTRACT

The use of micronutrients such as vitamin D could improve the response to viral vaccines, particularly in immunosuppressed and immunosenescent subjects. Here, we analysed the association between serum 25-hydroxyvitamin D (25OHD) levels and the immune response elicited by the BNT162b2 vaccine in a cohort of 101 healthcare workers naïve for SARS-CoV-2 infection. We observed no significant differences in anti-spike (S) IgG and T-cell responses according to the 25OHD status at baseline. However, significant correlations between the 25OHD concentration at baseline and (i) the anti-S response (p < 0.020) and (ii) the neutralizing antibody (NT) titre (p = 0.040) at six months after the second dose were detected. We concluded that adequate levels of vitamin D may improve the immune response to mRNA vaccines such as BNT162b2, and that further larger studies are warranted in order to confirm these preliminary observations.

4.
Diagnostics (Basel) ; 12(6)2022 Jun 20.
Article in English | MEDLINE | ID: covidwho-1969126

ABSTRACT

Since the identification of the new severe acute respiratory syndrome virus 2 (SARS-CoV-2), a huge effort in terms of diagnostic strategies has been deployed. To date, serological assays represent a valuable tool for the identification of recovered COVID-19 patients and for the monitoring of immune response elicited by vaccination. However, the role of T-cell response should be better clarified and simple and easy to perform assays should be routinely introduced. The main aim of this study was to compare a home-made assay for whole blood stimulation with a standardized ELISpot assay design in our laboratory for the assessment of spike-specific T-cell response in vaccinated subjects. Even if a good correlation between the assays was reported, a higher percentage of responder subjects was reported for immunocompromised subjects with ELISpot assay (56%) than home-made whole blood stimulation assay (33%). Additionally, three commercial assays were compared with our home-made assay, reporting a good agreement in terms of both positive and negative results.

5.
Knowl Based Syst ; 253: 109539, 2022 Oct 11.
Article in English | MEDLINE | ID: covidwho-1966919

ABSTRACT

Alongside the currently used nasal swab testing, the COVID-19 pandemic situation would gain noticeable advantages from low-cost tests that are available at any-time, anywhere, at a large-scale, and with real time answers. A novel approach for COVID-19 assessment is adopted here, discriminating negative subjects versus positive or recovered subjects. The scope is to identify potential discriminating features, highlight mid and short-term effects of COVID on the voice and compare two custom algorithms. A pool of 310 subjects took part in the study; recordings were collected in a low-noise, controlled setting employing three different vocal tasks. Binary classifications followed, using two different custom algorithms. The first was based on the coupling of boosting and bagging, with an AdaBoost classifier using Random Forest learners. A feature selection process was employed for the training, identifying a subset of features acting as clinically relevant biomarkers. The other approach was centered on two custom CNN architectures applied to mel-Spectrograms, with a custom knowledge-based data augmentation. Performances, evaluated on an independent test set, were comparable: Adaboost and CNN differentiated COVID-19 positive from negative with accuracies of 100% and 95% respectively, and recovered from negative individuals with accuracies of 86.1% and 75% respectively. This study highlights the possibility to identify COVID-19 positive subjects, foreseeing a tool for on-site screening, while also considering recovered subjects and the effects of COVID-19 on the voice. The two proposed novel architectures allow for the identification of biomarkers and demonstrate the ongoing relevance of traditional ML versus deep learning in speech analysis.

6.
Bastard, Paul, Vazquez, Sara, Liu, Jamin, Laurie, Matthew T.; Wang, Chung Yu, Gervais, Adrian, Le Voyer, Tom, Bizien, Lucy, Zamecnik, Colin, Philippot, Quentin, Rosain, Jérémie, Catherinot, Emilie, Willmore, Andrew, Mitchell, Anthea M.; Bair, Rebecca, Garçon, Pierre, Kenney, Heather, Fekkar, Arnaud, Salagianni, Maria, Poulakou, Garyphallia, Siouti, Eleni, Sahanic, Sabina, Tancevski, Ivan, Weiss, Günter, Nagl, Laurenz, Manry, Jérémy, Duvlis, Sotirija, Arroyo-Sánchez, Daniel, Paz Artal, Estela, Rubio, Luis, Perani, Cristiano, Bezzi, Michela, Sottini, Alessandra, Quaresima, Virginia, Roussel, Lucie, Vinh, Donald C.; Reyes, Luis Felipe, Garzaro, Margaux, Hatipoglu, Nevin, Boutboul, David, Tandjaoui-Lambiotte, Yacine, Borghesi, Alessandro, Aliberti, Anna, Cassaniti, Irene, Venet, Fabienne, Monneret, Guillaume, Halwani, Rabih, Sharif-Askari, Narjes Saheb, Danielson, Jeffrey, Burrel, Sonia, Morbieu, Caroline, Stepanovskyy, Yurii, Bondarenko, Anastasia, Volokha, Alla, Boyarchuk, Oksana, Gagro, Alenka, Neuville, Mathilde, Neven, Bénédicte, Keles, Sevgi, Hernu, Romain, Bal, Antonin, Novelli, Antonio, Novelli, Giuseppe, Saker, Kahina, Ailioaie, Oana, Antolí, Arnau, Jeziorski, Eric, Rocamora-Blanch, Gemma, Teixeira, Carla, Delaunay, Clarisse, Lhuillier, Marine, Le Turnier, Paul, Zhang, Yu, Mahevas, Matthieu, Pan-Hammarström, Qiang, Abolhassani, Hassan, Bompoil, Thierry, Dorgham, Karim, consortium, Covid Hge, French, Covid study group, consortium, Comet, Gorochov, Guy, Laouenan, Cédric, Rodríguez-Gallego, Carlos, Ng, Lisa F. P.; Renia, Laurent, Pujol, Aurora, Belot, Alexandre, Raffi, François, Allende, Luis M.; Martinez-Picado, Javier, Ozcelik, Tayfun, Keles, Sevgi, Imberti, Luisa, Notarangelo, Luigi D.; Troya, Jesus, Solanich, Xavier, Zhang, Shen-Ying, Puel, Anne, Wilson, Michael R.; Trouillet-Assant, Sophie, Abel, Laurent, Jouanguy, Emmanuelle, Ye, Chun Jimmie, Cobat, Aurélie, Thompson, Leslie M.; Andreakos, Evangelos, Zhang, Qian, Anderson, Mark S.; Casanova, Jean-Laurent, DeRisi, Joseph L..
Science immunology ; 2022.
Article in English | EuropePMC | ID: covidwho-1918542

ABSTRACT

Life-threatening ‘breakthrough’ cases of critical COVID-19 are attributed to poor or waning antibody response to the SARS-CoV-2 vaccine in individuals already at risk. Pre-existing autoantibodies (auto-Abs) neutralizing type I IFNs underlie at least 15% of critical COVID-19 pneumonia cases in unvaccinated individuals;however, their contribution to hypoxemic breakthrough cases in vaccinated people remains unknown. Here, we studied a cohort of 48 individuals (age 20-86 years) who received 2 doses of an mRNA vaccine and developed a breakthrough infection with hypoxemic COVID-19 pneumonia 2 weeks to 4 months later. Antibody levels to the vaccine, neutralization of the virus, and auto-Abs to type I IFNs were measured in the plasma. Forty-two individuals had no known deficiency of B cell immunity and a normal antibody response to the vaccine. Among them, ten (24%) had auto-Abs neutralizing type I IFNs (aged 43-86 years). Eight of these ten patients had auto-Abs neutralizing both IFN-α2 and IFN-ω, while two neutralized IFN-ω only. No patient neutralized IFN-β. Seven neutralized 10 ng/mL of type I IFNs, and three 100 pg/mL only. Seven patients neutralized SARS-CoV-2 D614G and the Delta variant (B.1.617.2) efficiently, while one patient neutralized Delta slightly less efficiently. Two of the three patients neutralizing only 100 pg/mL of type I IFNs neutralized both D61G and Delta less efficiently. Despite two mRNA vaccine inoculations and the presence of circulating antibodies capable of neutralizing SARS-CoV-2, auto-Abs neutralizing type I IFNs may underlie a significant proportion of hypoxemic COVID-19 pneumonia cases, highlighting the importance of this particularly vulnerable population. Type I IFN auto-Abs are found in 20% of hypoxemic, mRNA vaccinated COVID-19 patients despite SARS-CoV-2 neutralizing antibodies. Description

7.
Int J Infect Dis ; 2022 Jul 05.
Article in English | MEDLINE | ID: covidwho-1914483

ABSTRACT

BACKGROUND: Vaccination is the best strategy to contrast coronavirus disease 2019 (COVID-19).We aimed to determine antibodies against SARS-CoV-2 in breastmilk and serum of mothers vaccinated with mRNA vaccine. METHODS: this prospective study included 18 lactating women vaccinated with BNT162b2 vaccine. Serum and breastmilk were collected before the first dose (T0), at second dose (T1), 3 weeks (T2) and 6 months later (T3). Serum anti-SARS-CoV-2 Spike (S) IgG and IgA were measured by a semi-quantitative ELISA, secretory antibody (s) IgG and IgA in breastmilk by a quantitative analysis. RESULTS: we detected serum anti-S IgG and IgA in all women after vaccination. Specific IgG and IgA were higher at T1, T2 and T3 compared to T0 (p<0.0001). Higher antibody levels were observed at T2, lower values were observed at T3 vs T2 (p=0.007). After six months, all patients had serum IgG but 3 out of 18 (16%) had serum IgA. In breastmilk, sIgA were present at T1 and T2 and decreased after six months at T3 (p=0.002). Breastmilk sIgG levels increased at T1 and T2 and peaked at T3 (p=0.008). CONCLUSION: secretory antibodies were transmitted through breastmilk until 6 months after anti COVID-19 mRNA vaccination. Protection of the newborn through breastfeeding need to be addressed.

8.
Rheumatology (Oxford) ; 2022 Jun 23.
Article in English | MEDLINE | ID: covidwho-1901234

ABSTRACT

OBJECTIVES: To analyse humoral and cellular immune response to messenger RNA (mRNA) COVID-19 vaccines in patients with giant cell arteritis (GCA). METHODS: Consecutive patients with a diagnosis of GCA receiving two doses of BNT162b2 vaccine were assessed at baseline and three weeks from the second vaccine dose. Healthy subjects (n = 51) were included as controls (HC). Humoral response was assessed with Spike-specific IgG antibody response (S-IgG) and neutralising antibodies (NtAb). Specific T cell response was assessed by Enzyme linked immunospot (ELISpot). RESULTS: Of 56 included patients with GCA, 44 were eligible after exclusion of previous evidence of COVID-19 and incomplete follow-up. A significant proportion of patients with GCA (91%) demonstrated antibody (S-IgG) response, however this was significantly lower than HC (100%); p< 0.0001. Neutralising activity was not detected in 16% of patients with GCA. Antibody titres (S-IgG and NtAb) were significantly lower compared with HC. Humoral response (S-IgG and NtAb) was significantly hampered by treatment with methotrexate (MTX). Cellular response was lacking in 30% of patients with GCA (vs 0% in HC); p< 0.0001. Cellular response was significantly influenced by the levels of baseline peripheral T-lymphocytes and by glucocorticoid treatment. Treatment with tocilizumab did not affect any level of the immune response elicited by vaccination. CONCLUSIONS: Although patients with GCA apparently achieve a robust antibody seroconversion, there is a significant impairment of the neutralising activity. MTX significantly reduced all levels of the humoral response. Up to one third of patients do not develop a cellular immune protection in response to COVID-19 vaccination.

9.
Microorganisms ; 10(6):1250, 2022.
Article in English | MDPI | ID: covidwho-1894334

ABSTRACT

We compared the development and persistence of antibody and T-cell responses elicited by the mRNA BNT162b2 vaccine or SARS-CoV-2 infection. We analysed 37 post-COVID-19 patients (15 with pneumonia and 22 with mild symptoms) and 20 vaccinated subjects. Anti-Spike IgG and neutralising antibodies were higher in vaccinated subjects and in patients with pneumonia than in patients with mild COVID-19, and persisted at higher levels in patients with pneumonia while declining in vaccinated subjects. However, the booster dose restored the initial antibody levels. The proliferative CD4+ T-cell response was similar in vaccinated subjects and patients with pneumonia, but was lower in mild COVID-19 patients and persisted in both vaccinated subjects and post-COVID patients. Instead, the proliferative CD8+ T-cell response was lower in vaccinated subjects than in patients with pneumonia, decreased six months after vaccination, and was not restored after the booster dose. The cytokine profile was mainly TH1 in both vaccinated subjects and post-COVID-19 patients. The mRNA BNT162b2 vaccine elicited higher levels of antibody and CD4+ T-cell responses than those observed in mild COVID-19 patients. While the antibody response declined after six months and required a booster dose to be restored at the initial levels, the proliferative CD4+ T-cell response persisted over time.

10.
Diagnostics ; 12(6):1509, 2022.
Article in English | MDPI | ID: covidwho-1893866

ABSTRACT

Since the identification of the new severe acute respiratory syndrome virus 2 (SARS-CoV-2), a huge effort in terms of diagnostic strategies has been deployed. To date, serological assays represent a valuable tool for the identification of recovered COVID-19 patients and for the monitoring of immune response elicited by vaccination. However, the role of T-cell response should be better clarified and simple and easy to perform assays should be routinely introduced. The main aim of this study was to compare a home-made assay for whole blood stimulation with a standardized ELISpot assay design in our laboratory for the assessment of spike-specific T-cell response in vaccinated subjects. Even if a good correlation between the assays was reported, a higher percentage of responder subjects was reported for immunocompromised subjects with ELISpot assay (56%) than home-made whole blood stimulation assay (33%). Additionally, three commercial assays were compared with our home-made assay, reporting a good agreement in terms of both positive and negative results.

11.
Immunotherapy ; 14(12): 915-925, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-1892545

ABSTRACT

Patients with cancer have a higher risk of severe COVID-19, and expert consensus advocates for COVID-19 vaccination in this population. Some cases of autoimmune hepatitis have been described after the administration of COVID-19 vaccine in the people in apparently good health. Immune checkpoint inhibitors (ICIs) are responsible for a wide spectrum of immune-related adverse events (irAEs). This article reports a case of hepatitis and colitis in a 52-year-old woman who was undergoing immunotherapy and was HBV positive 10 days after receiving the first Pfizer-BioNTech COVID-19 vaccine dose. Because both ICIs and the COVID-19 vaccines stimulate the immune response, the authors hypothesize that these vaccines may increase the incidence of irAEs during ICI treatment. There is a complex interplay between the immune-mediated reaction triggered by the vaccination and PD-L1 co-administration.


Patients with cancer have a higher risk of severe COVID-19, and expert consensus advocates for COVID-19 vaccination in this population. Some reports have described autoimmune hepatitis after the administration of COVID-19 vaccine. It is difficult, however, to establish a causal relationship between COVID-19 vaccination and autoimmune hepatitis. This article reports a case of hepatitis and colitis in a 52-year-old woman with lung cancer who was undergoing immunotherapy and was was found to be HBV positive 10 days after her first Pfizer-BioNTech COVID-19 vaccine dose. Because both immunotherapy and COVID-19 vaccines stimulate the immune response, the authors hypothesize that these vaccines may increase the incidence of immune-related side effects.


Subject(s)
Antineoplastic Agents, Immunological , COVID-19 Vaccines , COVID-19 , Hepatitis , Neoplasms , Antineoplastic Agents, Immunological/therapeutic use , BNT162 Vaccine , COVID-19/therapy , COVID-19 Vaccines/adverse effects , Female , Hepatitis/etiology , Humans , Immunologic Factors/therapeutic use , Immunotherapy/adverse effects , Middle Aged , SARS-CoV-2 , Vaccination/adverse effects
12.
Vaccines (Basel) ; 10(6)2022 Jun 09.
Article in English | MEDLINE | ID: covidwho-1884445

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has severely impacted on public health, mainly on immunosuppressed patients, including solid organ transplant recipients. Vaccination represents a valuable tool for the prevention of severe SARS-CoV-2 infection, and the immunogenicity of mRNA vaccines has been evaluated in transplanted patients. In this study, we investigated the role of a third dose of the BNT162b2 vaccine in a cohort of kidney transplant recipients, analyzing both humoral and cell-mediated responses. We observed an increased immune response after the third dose of the vaccine, especially in terms of Spike-specific T cell response. The level of seroconversion remained lower than 50% even after the administration of the third dose. Mycophenolate treatment, steroid administration and age seemed to be associated with a poor immune response. In our cohort, 11/45 patients experienced a SARS-CoV-2 infection after the third vaccine dose. HLA antibodies appearance was recorded in 7 out 45 (15.5%) patients, but none of the patients developed acute renal rejection. Further studies for the evaluation of long-term immune responses are still ongoing, and the impact of a fourth dose of the vaccine will be evaluated.

13.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-338324

ABSTRACT

Additional COVID-19 vaccines that are safe, easy to manufacture, and immunogenic are needed for global vaccine equity. Here, we developed a recombinant type 5 adenovirus vector encoding for the SARS-CoV-2-S1 subunit antigen and nucleocapsid as a fusion protein (Ad5.SARS-CoV-2-S1N) delivered to BALB/c mice through multiple vaccine administration routes. A single subcutaneous (S.C.) immunization with Ad5.SARS-CoV-2-S1N induced a similar humoral response, along with a significantly higher S1-specific cellular response, as a recombinant type 5 adenovirus vector encoding for S1 alone (Ad5.SARS-CoV-2-S1). Immunogenicity was improved by homologous prime boost strategies, using either S.C. or intranasal (I.N.) delivery of Ad5.SARS-CoV-2-S1N, and further improved through heterologous prime boost, with traditional intramuscular (I.M.) injection, using subunit recombinant S1 protein. Priming with low dose (1×10 10 v.p.) of Ad5.SARS-CoV-2-S1N and boosting with either wildtype recombinant rS1 or B.1.351 recombinant rS1 induced a robust neutralizing response, that was sustained against immune evasive Beta and Gamma SARS-CoV-2 variants, along with a long-lived plasma cell response in the bone marrow 29 weeks post vaccination. This novel Ad5-vectored SARS-CoV-2 vaccine candidate showed promising immunogenicity in mice and supports the further development of COVID-19 based vaccines incorporating the nucleoprotein as a target antigen.

14.
Vaccines (Basel) ; 10(5)2022 Apr 29.
Article in English | MEDLINE | ID: covidwho-1820440

ABSTRACT

SARS-CoV-2 still represents a global health burden, causing more than six million deaths worldwide. Moreover, the emergence of new variants has posed new issues in terms of vaccine efficacy and immunogenicity. In this study, we aimed to evaluate the neutralizing antibody response against SARS-CoV-2 variants in different cohorts of vaccinated and unvaccinated subjects. Four-fold diluted sera from SARS-CoV-2 naïve and recovered subjects vaccinated with two or three doses of the BNT162b2 vaccine were challenged against 14 SARS-CoV-2 variants, and the SARS-CoV-2 neutralizing antibody titer was measured. Results were compared with those obtained from unvaccinated COVID-19 recovered patients. Overall, a better SARS-CoV-2 NT Abs response was observed in recovered vaccinated subjects after three doses of the vaccine when compared to unvaccinated patients and vaccinated subjects with only two doses. Additionally, the lowest level of response was observed against the Omicron variant. In conclusion, third doses of BNT162b2 vaccine seems to elicit a sustained response against the large majority of variants.

15.
BMC Med ; 20(1): 102, 2022 03 03.
Article in English | MEDLINE | ID: covidwho-1724486

ABSTRACT

BACKGROUND: The COVID-19 pandemic is caused by the betacoronavirus SARS-CoV-2. In November 2021, the Omicron variant was discovered and immediately classified as a variant of concern (VOC), since it shows substantially more mutations in the spike protein than any previous variant, especially in the receptor-binding domain (RBD). We analyzed the binding of the Omicron RBD to the human angiotensin-converting enzyme-2 receptor (ACE2) and the ability of human sera from COVID-19 patients or vaccinees in comparison to Wuhan, Beta, or Delta RBD variants. METHODS: All RBDs were produced in insect cells. RBD binding to ACE2 was analyzed by ELISA and microscale thermophoresis (MST). Similarly, sera from 27 COVID-19 patients, 81 vaccinated individuals, and 34 booster recipients were titrated by ELISA on RBDs from the original Wuhan strain, Beta, Delta, and Omicron VOCs. In addition, the neutralization efficacy of authentic SARS-CoV-2 wild type (D614G), Delta, and Omicron by sera from 2× or 3× BNT162b2-vaccinated persons was analyzed. RESULTS: Surprisingly, the Omicron RBD showed a somewhat weaker binding to ACE2 compared to Beta and Delta, arguing that improved ACE2 binding is not a likely driver of Omicron evolution. Serum antibody titers were significantly lower against Omicron RBD compared to the original Wuhan strain. A 2.6× reduction in Omicron RBD binding was observed for serum of 2× BNT162b2-vaccinated persons. Neutralization of Omicron SARS-CoV-2 was completely diminished in our setup. CONCLUSION: These results indicate an immune escape focused on neutralizing antibodies. Nevertheless, a boost vaccination increased the level of anti-RBD antibodies against Omicron, and neutralization of authentic Omicron SARS-CoV-2 was at least partially restored. This study adds evidence that current vaccination protocols may be less efficient against the Omicron variant.


Subject(s)
COVID-19 , COVID-19/prevention & control , Humans , Pandemics , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics
17.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-315452

ABSTRACT

BNT162b2 vaccine was introduced in Italy on 27th December 2020 and healthcare workers were rapidly vaccinated. In this study, we demonstrated that one vaccine dose was sufficient for eliciting a sustained humoral and cell-mediated response in SARS-CoV-2 experienced healthcare workers but had a lower effect in SARS-CoV-2 naïve subjects. However, 98% naïve subjects developed both neutralizing antibodies and Spike-specific T-cells after the second dose. Moreover, the antibody and T-cell responses were effective against viral variants since a partial reduction in antibody response was observed only against the South-African variant in SARS-CoV-2 naïve individuals, while the T-cell response was less affected.

18.
Transfus Apher Sci ; : 103398, 2022 Feb 16.
Article in English | MEDLINE | ID: covidwho-1683633

ABSTRACT

BACKGROUND: Test the ability of Mirasol Pathogen Reduction Technology (PRT, Terumo BCT, Lakewood Co, USA) treatment with riboflavin and ultraviolet light (R + UV) in reducing SARS-CoV-2 infectivity while maintaining blood product quality. MATERIAL AND METHODS: SARS-CoV-2 strains were isolated and titrated to prepare cell free virus for plasma units infection. The units were then under treatment with Mirasol PRT. The infectious titers were determined before and after treatment with an in house microtitration assay on Vero E6 cells. Thirty-six plasma pool bags underwent PRT treatment. RESULTS: In all the experiments, the measured titer following riboflavin and UV treatment was below the limit of detection of microtitration assay for all the different SARS-CoV-2 strains. Despite the high copies number detected by RT-PCR for each viral strain after treatment, viruses were completely inactivated and not able to infect VERO E6 cells. CONCLUSION: Riboflavin and UV light treatment effectively reduced the virus titers of human plasma to the limit of detection in tissue culture, regardless of the strain. These data suggest that pathogen reduction in blood products highlight the safety of CP therapy procedures for critically ill COVID-19 patients, while maintaining blood product quality.

19.
iScience ; 25(2): 103743, 2022 Feb 18.
Article in English | MEDLINE | ID: covidwho-1611783

ABSTRACT

Information concerning the longevity of immunity to SARS-CoV-2 following natural infection may have considerable implications for durability of immunity induced by vaccines. Here, we monitored the SARS-CoV-2 specific immune response in COVID-19 patients followed up to 15 months after symptoms onset. Following a peak at day 15-28 postinfection, the IgG antibody response and plasma neutralizing titers gradually decreased over time but stabilized after 6 months. Compared to G614, plasma neutralizing titers were more than 8-fold lower against variants Beta, Gamma, and Delta. SARS-CoV-2-specific memory B and T cells persisted in the majority of patients up to 15 months although a significant decrease in specific T cells, but not B cells, was observed between 6 and 15 months. Antiviral specific immunity, especially memory B cells in COVID-19 convalescent patients, is long-lasting, but some variants of concern may at least partially escape the neutralizing activity of plasma antibodies.

20.
J Voice ; 2021 Nov 26.
Article in English | MEDLINE | ID: covidwho-1607509

ABSTRACT

Many virological tests have been implemented during the Coronavirus Disease 2019 (COVID-19) pandemic for diagnostic purposes, but they appear unsuitable for screening purposes. Furthermore, current screening strategies are not accurate enough to effectively curb the spread of the disease. Therefore, the present study was conducted within a controlled clinical environment to determine eventual detectable variations in the voice of COVID-19 patients, recovered and healthy subjects, and also to determine whether machine learning-based voice assessment (MLVA) can accurately discriminate between them, thus potentially serving as a more effective mass-screening tool. Three different subpopulations were consecutively recruited: positive COVID-19 patients, recovered COVID-19 patients and healthy individuals as controls. Positive patients were recruited within 10 days from nasal swab positivity. Recovery from COVID-19 was established clinically, virologically and radiologically. Healthy individuals reported no COVID-19 symptoms and yielded negative results at serological testing. All study participants provided three trials for multiple vocal tasks (sustained vowel phonation, speech, cough). All recordings were initially divided into three different binary classifications with a feature selection, ranking and cross-validated RBF-SVM pipeline. This brough a mean accuracy of 90.24%, a mean sensitivity of 91.15%, a mean specificity of 89.13% and a mean AUC of 0.94 across all tasks and all comparisons, and outlined the sustained vowel as the most effective vocal task for COVID discrimination. Moreover, a three-way classification was carried out on an external test set comprised of 30 subjects, 10 per class, with a mean accuracy of 80% and an accuracy of 100% for the detection of positive subjects. Within this assessment, recovered individuals proved to be the most difficult class to identify, and all the misclassified subjects were declared positive; this might be related to mid and short-term vocal traces of COVID-19, even after the clinical resolution of the infection. In conclusion, MLVA may accurately discriminate between positive COVID-19 patients, recovered COVID-19 patients and healthy individuals. Further studies should test MLVA among larger populations and asymptomatic positive COVID-19 patients to validate this novel screening technology and test its potential application as a potentially more effective surveillance strategy for COVID-19.

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