Longitudinal characterisation of B and T-cell immune responses after the booster dose of COVID-19 mRNA-vaccine in people with multiple sclerosis using different disease-modifying therapies.

BACKGROUND: The decline of humoral response to COVID-19 vaccine led to authorise a booster dose. Here, we characterised the kinetics of B-cell and T-cell immune responses in patients with multiple sclerosis (PwMS) after the booster dose. METHODS: We enrolled 22 PwMS and 40 healthcare workers (HCWs) after 4-6 weeks from the booster dose (T3). Thirty HCWs and 19 PwMS were also recruited 6 months (T2) after the first dose. Antibody response was measured by anti-receptor-binding domain (RBD)-IgG detection, cell-mediated response by an interferon (IFN)-γ release assay (IGRA), Th1 cytokines and T-cell memory profile by flow cytometry. RESULTS: Booster dose increased anti-RBD-IgG titers in fingolimod-treated, cladribine-treated and IFN-ß-treated patients, but not in ocrelizumab-treated patients, although antibody titres were lower than HCWs. A higher number of fingolimod-treated patients seroconverted at T3. Differently, T-cell response evaluated by IGRA remained stable in PwMS independently of therapy. Spike-specific Th1-cytokine response was mainly CD4+ T-cell-mediated, and in PwMS was significantly reduced (p<0.0001) with impaired IL-2 production compared with HCWs at T3. In PwMS, total Th1 and IFN-γ CD4+ T-cell responders to spike protein were increased from T2 to T3.Compared with HCWs, PwMS presented a higher frequency of CD4+ and CD8+ terminally differentiated effector memory cells and of CD4+ effector memory (TEM) cells, independently of the stimulus suggesting the association of this phenotype with MS status. CD4+ and CD8+ TEM cell frequency was further increased at T3 compared with T2. CONCLUSIONS: COVID-19 vaccine booster strengthens humoral and Th1-cell responses and increases TEM cells in PwMS.

Dynamic Evolution of Humoral and T-Cell Specific Immune Response to COVID-19 mRNA Vaccine in Patients with Multiple Sclerosis Followed until the Booster Dose.

This study characterizes antibody and T-cell immune responses over time until the booster dose of COronaVIrus Disease 2019 (COVID-19) vaccines in patients with multiple sclerosis (PwMS) undergoing different disease-modifying treatments (DMTs). We prospectively enrolled 134 PwMS and 99 health care workers (HCWs) having completed the two-dose schedule of a COVID-19 mRNA vaccine within the last 2-4 weeks (T0) and followed them 24 weeks after the first dose (T1) and 4-6 weeks after the booster (T2). PwMS presented a significant reduction in the seroconversion rate and anti-receptor-binding domain (RBD)-Immunoglobulin (IgG) titers from T0 to T1 (p < 0.0001) and a significant increase from T1 to T2 (p < 0.0001). The booster dose in PwMS showed a good improvement in the serologic response, even greater than HCWs, as it promoted a significant five-fold increase of anti-RBD-IgG titers compared with T0 (p < 0.0001). Similarly, the T-cell response showed a significant 1.5- and 3.8-fold increase in PwMS at T2 compared with T0 (p = 0.013) and T1 (p < 0.0001), respectively, without significant modulation in the number of responders. Regardless of the time elapsed since vaccination, most ocrelizumab- (77.3%) and fingolimod-treated patients (93.3%) showed only a T-cell-specific or humoral-specific response, respectively. The booster dose reinforces humoral- and cell-mediated-specific immune responses and highlights specific DMT-induced immune frailties, suggesting the need for specifically tailored strategies for immune-compromised patients to provide primary prophylaxis, early SARS-CoV-2 detection and the timely management of COVID-19 antiviral treatments.

Multi-omics approach to COVID-19: a domain-based literature review.

BACKGROUND: Omics data, driven by rapid advances in laboratory techniques, have been generated very quickly during the COVID-19 pandemic. Our aim is to use omics data to highlight the involvement of specific pathways, as well as that of cell types and organs, in the pathophysiology of COVID-19, and to highlight their links with clinical phenotypes of SARS-CoV-2 infection. METHODS: The analysis was based on the domain model, where for domain it is intended a conceptual repository, useful to summarize multiple biological pathways involved at different levels. The relevant domains considered in the analysis were: virus, pathways and phenotypes. An interdisciplinary expert working group was defined for each domain, to carry out an independent literature scoping review. RESULTS: The analysis revealed that dysregulated pathways of innate immune responses, (i.e., complement activation, inflammatory responses, neutrophil activation and degranulation, platelet degranulation) can affect COVID-19 progression and outcomes. These results are consistent with several clinical studies. CONCLUSIONS: Multi-omics approach may help to further investigate unknown aspects of the disease. However, the disease mechanisms are too complex to be explained by a single molecular signature and it is necessary to consider an integrated approach to identify hallmarks of severity.

Comparative Chemical Compositions of Fresh and Stored Vesuvian PDO "Pomodorino Del Piennolo" Tomato and the Ciliegino Variety.

The Vesuvian Piennolo cherry tomato (Lycopersicon esculentum Miller) (PdP) is an old and typical variety grown in the Campania region (Italy). PdP is referred to as a long-storage tomato due to its thick and coriaceous skin that allows long post-harvest storage and it has been granted Protected Designation of Origin (PDO) status since 2009. In this study, the chemical composition, focusing in particular on organic acids, antioxidant molecules and volatile compounds, were investigated in PdP and compared to another typical variety in Campania, the Ciliegino tomato (CIL). Chemical characterization was evaluated for both the CIL and PdP varieties during storage in the same environmental conditions until deterioration of 50% of the fruits; deterioration occurred in PdP after 6 months and in CIL tomatoes after 1 month. The results demonstrated variation in the chemical profiles of both varieties with storage length. Particularly, the PdP variety appears richer in antioxidants compounds (i.e., chlorogenic acids and lycopene) and organic acids (i.e., glutamic and malic acids) than does CIL. Additionally, both varieties display different profiles of volatile bioactive compounds and they are differently influenced by the storage time. The results indicate a typical chemical composition of this long-storage tomato closely linked to the geographic origin area.

Multiple antimicrobial and immune-modulating activities of cysteamine in infectious diseases.

Infectious diseases are a major threat to global health and cause millions of deaths every year, particularly in developing countries. The emergence of multidrug resistance challenges current antimicrobial treatments, inducing uncertainty in therapeutic protocols. New compounds are therefore necessary. A drug repurposing approach could play a critical role in developing new treatments used either alone or in combination with standard therapy regimens. Herein, we focused on cysteamine, an aminothiol endogenously synthesized by human cells during the degradation of coenzyme-A, which is a drug approved for the treatment of nephropathic cystinosis. Cysteamine influences many biological processes due to the presence of the highly reactive thiol group. This review provides an overview of cysteamine-mediated effects on different viruses, bacteria and parasites, with a particular focus on infections caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), Mycobacterium tuberculosis, non-tuberculous mycobacteria (NTM), and Pseudomonas aeruginosa. Evidences for a potential use of cysteamine as a direct antimicrobial agent and/or a host-directed therapy, either alone or in combination with other antimicrobial drugs, are described.

Anti-RBD Antibody Levels and IFN-γ-Specific T Cell Response Are Associated with a More Rapid Swab Reversion in Patients with Multiple Sclerosis after the Booster Dose of COVID-19 Vaccination.

This study investigated the incidence and severity of SARS-CoV-2 breakthrough infections (BIs) and the time to swab reversion in patients with multiple sclerosis (PwMS) after the booster dose of COVID-19 mRNA vaccines. We enrolled 64 PwMS who had completed the three-dose mRNA vaccine schedule and had never experienced COVID-19 before. Among the 64 PwMS, 43.8% had BIs with a median time since the third vaccine dose of 155 days. BIs occurred more frequently in ocrelizumab-treated patients (64.7%). Patients with a relapsing-remitting MS course showed a reduced incidence of BIs compared with those with a primary-progressive disease (p = 0.002). Having anti-receptor-binding domain (RBD) antibodies represented a protective factor reducing the incidence of BIs by 60% (p = 0.042). The majority of BIs were mild, and the only severe COVID-19 cases were reported in patients with a high Expanded Disability Status Scale score (EDSS > 6). The median time for a negative swab was 11 days. Notably, fingolimod-treated patients take longer for a swab-negativization (p = 0.002). Conversely, having anti-RBD antibodies ≥ 809 BAU/mL and an IFN-γ-specific T cell response ≥ 16 pg/mL were associated with a shorter time to swab-negativization (p = 0.051 and p = 0.018, respectively). In conclusion, the immunological protection from SARS-CoV-2 infection may differ among PwMS according to DMTs.

Initial immune response after exposure to Mycobacterium tuberculosis or to SARS-COV-2: similarities and differences.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb) and Coronavirus disease-2019 (COVID-19), whose etiologic agent is severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), are currently the two deadliest infectious diseases in humans, which together have caused about more than 11 million deaths worldwide in the past 3 years. TB and COVID-19 share several aspects including the droplet- and aerosol-borne transmissibility, the lungs as primary target, some symptoms, and diagnostic tools. However, these two infectious diseases differ in other aspects as their incubation period, immune cells involved, persistence and the immunopathological response. In this review, we highlight the similarities and differences between TB and COVID-19 focusing on the innate and adaptive immune response induced after the exposure to Mtb and SARS-CoV-2 and the pathological pathways linking the two infections. Moreover, we provide a brief overview of the immune response in case of TB-COVID-19 co-infection highlighting the similarities and differences of each individual infection. A comprehensive understanding of the immune response involved in TB and COVID-19 is of utmost importance for the design of effective therapeutic strategies and vaccines for both diseases.

Characterization of the immune impairment of patients with tuberculosis and COVID-19 coinfection.

OBJECTIVES: To characterize the plasma immune profile of patients with tuberculosis (TB)-COVID-19 compared with COVID-19, TB, or healthy controls and to evaluate in vitro the specific responses to SARS-CoV-2 and Mycobacterium tuberculosis (Mtb)-antigens. METHODS: We enrolled 119 subjects: 14 TB-COVID-19, 47 COVID-19, 38 TB, and 20 controls. The plasmatic levels of 27 immune factors were measured at baseline using a multiplex assay. The specific response to SARS-CoV-2 and Mtb antigens was evaluated using a home-made whole blood platform and QuantiFERON-Plus tubes, respectively. RESULTS: We found an immune signature (tumor necrosis factor [TNF]-α, macrophage inflammatory protein-1ß, and interleukin [IL]-9) associated with TB-COVID-19 coinfection compared with COVID-19 (P <0.05), and TNF-α showed the highest discriminant power. We also found another signature (TNF-α, IL-1ß, IL-17A, IL-5, fibroblast growth factor-basic, and granulocyte macrophage colony-stimulating factor [GM-CSF]) in coinfected patients compared with patients with TB (P <0.05), and among them, TNF-α and granulocyte macrophage colony-stimulating factor showed a non-negligible discriminating ability. Moreover, coinfected patients showed a significantly reduced SARS-CoV-2-specific response compared with COVID-19 for several pro-inflammatory cytokines/chemokines, anti-inflammatory cytokines, and growth factors (P ≤0.05). Furthermore, coinfection negatively affected the Mtb-specific response (P ≤0.05). CONCLUSION: We found immune signatures associated with TB-COVID-19 coinfection and observed a major impairment of SARS-CoV-2-specific and, to a lesser extent, the Mtb-specific immune responses. These findings further advance our knowledge of the immunopathology of TB-COVID-19 coinfection.

The Third Dose of BNT162b2 COVID-19 Vaccine Does Not "Boost" Disease Flares and Adverse Events in Patients with Rheumatoid Arthritis.

Data on the risk of adverse events (AEs) and disease flares in autoimmune rheumatic diseases (ARDs) after the third dose of COVID-19 vaccine are scarce. The aim of this multicenter, prospective study is to analyze the clinical and immunological safety of BNT162b2 vaccine in a cohort of rheumatoid arthritis (RA) patients followed-up from the first vaccine cycle to the third dose. The vaccine showed an overall good safety profile with no patient reporting serious AEs, and a low percentage of total AEs at both doses (40/78 (51.3%) and 13/47 (27.7%) patients after the second and third dose, respectively (p < 0.002). Flares were observed in 10.3% of patients after the end of the vaccination cycle and 12.8% after the third dose. Being vaccinated for influenza was inversely associated with the onset of AEs after the second dose, at both univariable (p = 0.013) and multivariable analysis (p = 0.027). This result could allow identification of a predictive factor of vaccine tolerance, if confirmed in larger patient populations. A higher disease activity at baseline was not associated with a higher incidence of AEs or disease flares. Effectiveness was excellent after the second dose, with only 1/78 (1.3%) mild breakthrough infection (BI) and worsened after the third dose, with 9/47 (19.2%) BI (p < 0.002), as a probable expression of the higher capacity of the Omicron variants to escape vaccine recognition.

Older Age, a High Titre of Neutralising Antibodies and Therapy with Conventional DMARDs Are Associated with Protection from Breakthrough Infection in Rheumatoid Arthritis Patients after the Booster Dose of Anti-SARS-CoV-2 Vaccine.

Objectives: We aimed to analyse the incidence and severity of breakthrough infections (BIs) in rheumatoid arthritis (RA) patients after a COronaVIrus Disease 2019 (COVID-19) vaccination booster dose. Methods: We enrolled 194 RA patients and 1002 healthcare workers (HCWs) as controls. Clinical, lifestyle and demographic factors were collected at the time of the third dose, and immunogenicity analyses were carried out in a subgroup of patients at 4-6 weeks after the third dose. Results: BIs were experienced by 42% patients (82/194) with a median time since the last vaccination of 176 days. Older age (>50 years; aHR 0.38, 95% CI: 0.20-0.74), receiving conventional synthetic disease modifying antirheumatic drugs (csDMARDs) (aHR 0.52, 95%CI: 0.30-0.90) and having a titre of neutralising antibodies >20 (aHR 0.36, 95% CI: 0.12-1.07) were identified as protective factors. Conversely, anti-IL6R treatment and anti-CD20 therapy increased BI probability. BIs were mostly pauci-symptomatic, but the hospitalisation incidence was significantly higher than in HCWs (8.5% vs. 0.19%); the main risk factor was anti-CD20 therapy. Conclusions: Being older than 50 years and receiving csDMARDs were shown to be protective factors for BI, whereas anti-IL6R or anti-CD20 therapy increased the risk. Higher neutralising antibody titres were associated with a lower probability of BI. If confirmed in a larger population, the identification of a protective cut-off would allow a personalised risk-benefit therapeutic management of RA patients.

Effect of fatty acid composition of vegetable oils on crystallization and gelation kinetics of oleogels based on natural wax.

This study aimed to understand the effect of fatty acid composition and viscosity of vegetable oils on network formation mechanism and physical properties of oleogels. To this purpose, 12 oleogels were prepared, by choosing 6 seed oils and two waxes, at a fixed oleogelator concentration (6%). The modified Avrami model correctly describes the crystallization profile (R2 > 0.98) and the oil type did not affect the Avrami index that ranged from 1.00 to 1.43. Independently from oleogelator, rice and hemp seed oils followed a 3-D network formation mechanism, while almond oil a 2-D mechanism. The strength and yield stress of carnauba wax oleogels increased with increasing saturated fatty acid amount, while in beeswax-based oleogels a more interconnected structure was associated with the length of the saturated fatty acid chain. Thus, the oleogels formation mechanism was closely related to the chemical composition of the solvent, even in highly monounsaturated or polyunsaturated oils.

Basil (Ocimum basilicum L.) Leaves as a Source of Bioactive Compounds.

Basil (Ocimum basilicum L.) is an annual spicy plant generally utilized as a flavouring agent for food. Basil leaves also have pharmaceutical properties due to the presence of polyphenols, phenolic acids, and flavonoids. In this work, carbon dioxide was employed to extract bioactive compounds from basil leaves. Extraction with supercritical CO2 (p = 30 MPa; T = 50 °C) for 2 h using 10% ethanol as a cosolvent was the most efficient method, with a yield similar to that of the control (100% ethanol) and was applied to two basil cultivars: "Italiano Classico" and "Genovese". Antioxidant activity, phenolic acid content, and volatile organic compounds were determined in the extracts obtained by this method. In both cultivars, the supercritical CO2 extracts showed antiradical activity (ABTS●+ assay), caffeic acid (1.69-1.92 mg/g), linalool (35-27%), and bergamotene (11-14%) contents significantly higher than those of the control. The polyphenol content and antiradical activity measured by the three assays were higher in the "Genovese" cultivar than in the "Italiano Classico" cultivar, while the linalool content was higher (35.08%) in the "Italiano Classico" cultivar. Supercritical CO2 not only allowed us to obtain extracts rich in bioactive compounds in an environmentally friendly way but also reduced ethanol consumption.

Cysteamine exerts in vitro antiviral activity against the SARS-CoV-2 Delta and Omicron variants.

The novel SARS-CoV-2 variants of concern (VOC) represent a considerable global alarm because their mutations are known to affect transmissibility and cause immune escape. While preventing severe disease and deaths, the available vaccines do not avoid infection; therefore, COVID-19 disease management still requires effective therapies. We have recently reported that the aminothiol cysteamine, a drug already applied to humans, exerts direct antiviral activity against SARS-CoV-2 and has in vitro immunomodulatory effect. To evaluate whether this compound exerts antiviral effects also against SARS-CoV-2 variants, we performed different infected cell-based assays using Wild type, Delta, or Omicron VOC. We found that cysteamine significantly reduces the cytopathic effect induced by SARS-CoV-2 Wild type strain and Delta variant in Vero E6 cells. On the other hand, cysteamine had no effects on the survival of cells infected with the Omicron variant, due to the lack of cytotoxicity on Vero E6 cells, at least when infected at MOI = 0.001 for 72 h. Moreover, cysteamine significantly reduced the production of Wild type, Delta, and Omicron variants as measured by the virus released in the culture media (Vero E6 and Calu-3 cells) and by transmission electron microscopy analysis (Vero E6 cells). Notably, cysteamine is more effective in inhibiting the Omicron rather than Delta or Wild type viruses, with an 80% inhibition of Omicron production compared to 40% of Wild type and Delta variant. Overall, our findings demonstrate that cysteamine exerts direct antiviral actions against SARS-CoV-2 Delta and Omicron variants, in addition to the Wild type virus. Our data further demonstrate that cysteamine is a good candidate as repurposing drug for the treatment of SARS-CoV-2 infection for the present and, likely, the future VOC and, therefore, it would be important to investigate its clinical relevance in randomized clinical trials.

Deep-frying purple potato Purple Majesty using sunflower oil: effect on the polyphenols, anthocyanins and antioxidant activity.

The potato is a root vegetable native to the Americas; it consists of the starchy tuber of the plant Solanum tuberosum. There are many varieties, and the flesh can have different colour ranging from yellow to red and purple. Coloured varieties have a denser texture and slightly nuttier, earthier flavour than other potatoes. The desirable quality characteristics of potatoes depends on the intended use, and the acceptability of raw potatoes is determined by size, shape, colour, and the quality of can be evaluated in terms of colour, flavour, and texture. Deep-frying is the century-old and it is among the most common cooking processes, still being used to prepare a variety of food products on both industrial and domestic scales. Frying the potatoes is among the tastiest and appreciated way to cook this vegetable. Purple fleshed potatoes are widely considered one of the best-tasting purple potatoes varieties, they have a nice taste and add colour to a meal. They are a source of beneficial health compounds which makes them interesting as functional food. The anthocyanins present in the Purple Majesty variety are interesting for their health promoting abilities, anti-oxidative activity, and even other health beneficial effects, e.g. anti-influenza virus activity, and anti-stomach cancer activity. The aim of this study has been to assess the effect of deep-frying of purple potato Purple Majesty using sunflower oil on the polyphenols, anthocyanins and to evaluate the antioxidant activity of the cooked matrix compared to the fresh one. The results seem to suggest that the healthy characteristics of this functional food are retained after the cooking by frying.

Humoral and cellular responses to spike of δ SARS-CoV-2 variant in vaccinated patients with immune-mediated inflammatory diseases.

OBJECTIVES: We assessed vaccination-induced antibody and cellular responses against spike from the ancestral strain and from the delta (δ) SARS-CoV-2 variant in patients with immune-mediated inflammatory diseases (IMIDs) on immunosuppressive therapy in comparison with immunocompetent subjects. METHODS: We enrolled patients with IMID and immunocompetent subjects who completed the vaccination schedule within 4-6 months from the first dose. The interferon (IFN)-γ-response to spike peptides that were derived from the ancestral and the δ SARS-CoV-2 were measured by ELISA. Anti-Receptor Binding Domain IgG antibodies were also evaluated. RESULTS: We enrolled 43 patients with IMID and nine immunocompetent subjects. No significant differences were found after comparing the specific immune response (IFN-γ) between patients with IMID and immunocompetent subjects to the ancestral (p = 0.36) or δ peptide pool (p = 0.51). Nevertheless, IFN-γ-specific responses to the ancestral or to the δ pools were reduced in subjects taking CTLA4-IgG or TNF-α inhibitors compared with subjects treated with IL-6 inhibitors or Disease Modifying Anti-Rheumatic Drugs. Regarding the antibody response, no significant differences were observed between patients with IMID and immunocompetent individuals. CONCLUSIONS: Cellular responses to δ SARS-CoV-2 variant remain largely intact in patients with IMID. However, the magnitude of these responses is dependent on the specific IMID immunosuppressive regimen. Serological response was also similar between the IMID and control groups.

Development of a High Oleic Cardoon Cell Culture Platform by SAD Overexpression and RNAi-Mediated FAD2.2 Silencing.

The development of effective tools for the sustainable supply of phyto-ingredients and natural substances with reduced environmental footprints can help mitigate the dramatic scenario of climate change. Plant cell cultures-based biorefineries can be a technological advancement to face this challenge and offer a potentially unlimited availability of natural substances, in a standardized composition and devoid of the seasonal variability of cultivated plants. Monounsaturated (MUFA) fatty acids are attracting considerable attention as supplements for biodegradable plastics, bio-additives for the cosmetic industry, and bio-lubricants. Cardoon (Cynara cardunculus L. var. altilis) callus cultures accumulate fatty acids and polyphenols and are therefore suitable for large-scale production of biochemicals and valuable compounds, as well as biofuel precursors. With the aim of boosting their potential uses, we designed a biotechnological approach to increase oleic acid content through Agrobacterium tumefaciens-mediated metabolic engineering. Bioinformatic data mining in the C. cardunculus transcriptome allowed the selection and molecular characterization of SAD (stearic acid desaturase) and FAD2.2 (fatty acid desaturase) genes, coding for key enzymes in oleic and linoleic acid formation, as targets for metabolic engineering. A total of 22 and 27 fast-growing independent CcSAD overexpressing (OE) and CcFAD2.2 RNAi knocked out (KO) transgenic lines were obtained. Further characterization of five independent transgenic lines for each construct demonstrated that, successfully, SAD overexpression increased linoleic acid content, e.g., to 42.5%, of the relative fatty acid content, in the CcSADOE6 line compared with 30.4% in the wild type (WT), whereas FAD2.2 silencing reduced linoleic acid in favor of the accumulation of its precursor, oleic acid, e.g., to almost 57% of the relative fatty acid content in the CcFAD2.2KO2 line with respect to 17.7% in the WT. Moreover, CcSADOE6 and CcFAD2.2KO2 were also characterized by a significant increase in total polyphenolic content up to about 4.7 and 4.1 mg/g DW as compared with 2.7 mg/g DW in the WT, mainly due to the accumulation of dicaffeoyl quinic and feruloyl quinic acids. These results pose the basis for the effective creation of an engineered cardoon cells-based biorefinery accumulating high levels of valuable compounds from primary and specialized metabolism to meet the industrial demand for renewable and sustainable sources of innovative bioproducts.

Humoral and Cellular Response to Spike of Delta SARS-CoV-2 Variant in Vaccinated Patients With Multiple Sclerosis.

Objectives: We assessed vaccination-induced antibody and cellular response against spike from the ancestral strain and from the Delta Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2) variant in patients with Multiple Sclerosis (MS) treated with disease modifying treatments. Methods: We enrolled 47 patients with MS and nine controls ("no MS") having completed the vaccination schedule within 4-6 months from the first dose. The Interferon (IFN)-γ-response to spike peptides derived from the ancestral and the Delta SARS-CoV-2 was measured by enzyme-linked immunoassay (ELISA). Anti-Receptor Binding Domain (RBD) IgG were also evaluated. Results: No significant differences were found comparing the IFN-γ-specific immune response between MS and "no MS" subjects to the ancestral (P = 0.62) or Delta peptide pools (P = 0.68). Nevertheless, a reduced IFN-γ-specific response to the ancestral or to the Delta pools was observed in subjects taking fingolimod or cladribine compared to subjects treated with ocrelizumab or IFN-ß. The antibody response was significantly reduced in patients with MS compared to "no MS" subjects (P = 0.0452) mainly in patients taking ocrelizumab or fingolimod. Conclusions: Cellular responses to Delta SARS-CoV-2 variant remain largely intact in patients with MS. However, the magnitude of these responses depends on the specific therapy.

Accuracy of QuantiFERON SARS-CoV-2 research use only assay and characterization of the CD4+ and CD8+ T cell-SARS-CoV-2 response: comparison with a homemade interferon-γ release assay.

OBJECTIVES: In this study, we aimed to characterize the SARS-CoV-2-specific T cell response detected by the QuantiFERON SARS-CoV-2 research use only assay in terms of accuracy and T cell subsets involved compared with a homemade interferon (IFN)-γ release assay (IGRA). METHODS: We evaluated T cell response by the standardized QuantiFERON SARS-CoV-2 tubes (antigen [Ag]1 and Ag2) and a homemade IGRA quantifying IFN-γ response to SARS-CoV-2 spike peptides (homemade-IGRA-SPIKE test). We evaluated the T cell subsets mediating the specific response using flow cytometry. RESULTS: We prospectively enrolled 66 individuals: COVID-19 or post-COVID-19 subjects and NO-COVID-19-vaccinated subjects, including healthy donors and immunocompromised subjects. The standardized kit detected 62.1% (41/66) of T cell responders. Ag2 tube showed a higher IFN-γ quantitative and qualitative response. Ag1 tube response was mainly mediated by CD4+ T cells; Ag2 tube response was mediated by CD4+ and CD8+ T cells. The homemade-IGRA-SPIKE test detected a higher number of responders (52/66, 78.8%) than the QuantiFERON SARS-CoV-2 assay (P = 0.056). The response was found in both T cell subsets, although a higher magnitude and response rate was observed in the CD4+ T cell subset. CONCLUSION: The QuantiFERON SARS-CoV-2 response is mediated by CD4+ and CD8+ T cells. A lower number of responders is found compared with the homemade-IGRA-SPIKE test, likely because of the different peptide composition.

Coordinated innate and T-cell immune responses in mild COVID-19 patients from household contacts of COVID-19 cases during the first pandemic wave.

Objective: To better define the immunopathogenesis of COVID-19, the present study aims to characterize the early immune responses to SARS-CoV-2 infection in household contacts of COVID-19 cases. In particular, innate, T- and B-cell specific responses were evaluated over time. Methods: Household contacts of COVID-19 cases screened for SARS-CoV-2 infection by nasopharyngeal swab for surveillance purposes were enrolled (T0, n=42). Of these, 28 subjects returned for a follow-up test (T1). The innate response was assessed by detecting a panel of soluble factors by multiplex-technology in plasma samples. Cell-mediated response was evaluated by measuring interferon (IFN)-γ levels by ELISA in plasma harvested from whole-blood stimulated with SARS-CoV-2 peptide pools, including spike (S), nucleocapsid (N) and membrane (M) proteins. The serological response was assessed by quantifying anti-Receptor-Binding-Domain (RBD), anti-Nucleocapsid (N), whole virus indirect immunofluorescence, and neutralizing antibodies. Results: At T0, higher levels of plasmatic IFN-α, IL-1ra, MCP-1 and IP-10, and lower levels of IL-1ß, IL-9, MIP-1ß and RANTES were observed in subjects with positive swab compared to individuals with a negative one (p<0.05). Plasmatic IFN-α was the only cytokine detectable in subjects with positive SARS-CoV-2 swabs with high accuracy for swab score positivity (0.93, p<0.0001). Among subjects with positive swabs, significant negative correlations were found among the RT-PCR cycle threshold values reported for genes S and N and IFN-α or IP-10 levels. At T0, the IFN-γ T-cell specific response was detected in 50% (5/10) of subjects with positive swab, while anti-RBD/anti-N antibodies showed a positivity rate of 10% (1/10). At T1, the IFN-γ T-cell specific response was detected in most of the confirmed-infection subjects (77.8%, 7/9), whereas the serological response was still observed in a minority of them (44.4%, 4/9). Overall, the swab test showed a moderate concordance with the T-cell response (78.6%, k=0.467), and a scarce concordance with the serological one (72.9%, k=0.194). Conclusions: Plasmatic IFN-α and the IFN-γ T-cell specific response appear early even in the absence of seroconversion, and show a greater positivity rate than the serological response in household contacts with positive swab.

Persistent Spike-specific T cell immunity despite antibody reduction after 3 months from SARS-CoV-2 BNT162b2-mRNA vaccine.

Vaccine is the main public health measure to reduce SARS-CoV-2 transmission and hospitalization, and a massive scientific effort worldwide resulted in the rapid development of effective vaccines. This work aimed to define the dynamics and persistence of humoral and cell-mediated immune response in Health Care Workers who received a two-dose BNT162b2-mRNA vaccination. Serological response was evaluated by quantifying anti-RBD and neutralizing antibodies while cell-mediated response was performed by a whole blood test quantifying Th1 cytokines (IFN-γ, TNF-α, IL-2) produced in response to Spike peptides. BNT162b2-mRNA vaccine induced both humoral and cell-mediated immune response against Spike in all HCW early after the second dose. After 12 weeks from vaccination, the titer of anti-RBD antibodies as well as their neutralization function decreased while the Spike-specific T-cells persisted at the same level as soon after vaccine boost. Of note, a correlation between cellular and humoral response persevered, suggesting the persistence of a coordinated immune response. The long lasting cell-mediated immune response after 3 months from vaccination highlight its importance in the maintaining of specific immunity able to expand again to fight eventual new antigen encountering.