ABSTRACT
Natalija Subotincic drinks from the well of Surrealism, in her case suffused with in-depth drawing research into Sigmund Freud's consulting room and study and the precise placement of objects within them. This has led her to draw with objects in space as she constructs her own ‘museum’ cabinet of curiosities. Emeritus Professor of Architectural History and Theory Alberto Pérez-Gómez takes us on a fascinating journey of discovery through her world. Copyright © 2022 John Wiley & Sons, Ltd.
ABSTRACT
Background: SARS-CoV-2 specific T-cell response has been associated with disease severity, immune memory and heterologous response to endemic coronaviruses (HCoV). However, an integrative approach combining a comprehensive analysis of the quality of SARS-CoV-2 specific T-cell response and antibody levels is needed. Methods: We assayed SARS-CoV-2 specific T-cell response in 103 participants. Thirty-seven (18 mild and 19 severe) were hospitalized during acute COVID-19 and 33 were recruited seven months after SARS-CoV-2 infection (19 previously hospitalized (H) and 14 non-hospitalized (NH) during acute infection). Pre-COVID-19 healthy donors (HD, n=33) were included. PBMCs were stimulated with Spike (S) and Nucleocapside (N) SARS-CoV-2 peptide pools. Likewise, an optimized peptide pool of HCoV S protein was used in HD. T-cell polyfunctionality by intracellular cytokine staining (IFN-γ, IL-2, TNF-α, CD107a and perforin (PRF)) was assayed by multiparametric flow cytometry together with measurements of T cell subsets, activation, exhaustion and senescence. Anti-S SARS-CoV-2 and HCoV IgG titers and pro-inflammatory markers were measured in plasma. Non-parametric statistic was used for the analysis. Results: Mild disease was associated with high T-cell polyfunctionality biased to IL-2 production and inversely correlated with anti-S IgG levels (eg, N-specific EM CD4+ IL-2+ T-cell, r=-0.594, p=0.004). However, only IFN-γ combinations without PRF production was mostly observed for severe disease (eg, S-specific TEMRA CD4+ CD107a-IFN-γ+IL-2-PRF-TNF-α-T-cells, p=0.008). Moreover, this response was long-lasting seven months after SARS-CoV-2 infection. Both NH and H individuals presented robust anti-S IgG levels and SARS-CoV-2 specific T-cell response. In addition, only H individuals showed a T-cell exhaustion profile (eg, TEMRA CD4+ TIGIT+ T cells, p=0.0004). Combinations including IL-2, but not IFN-γ, in response to HCoV S protein, were associated with SARS-CoV-2 S-specific T-cell response in HD (eg, S-specific CM CD8+ CD107a-IFN-γ-IL-2+PRF-TNF-α-T-cells, r=5414, p=0.001). Conclusion: T-cell polyfunctionality features were associated with disease severity. Moreover, T-cell response was robust seven months after infection, although previously hospitalized patients showed signs of exhaustion. SARS-CoV-2 and HCoV immune cross-reactivity have implications for protective immunity against SARS-CoV-2 to design new prototypes of vaccines in order to achieve of broader long-lasting protection against COVID-19.
ABSTRACT
Background: The number of cases of SARS-CoV-2 infection after BNT162b2 mRNA vaccination is significantly higher in elderly people, which has been associated to lower frequencies of SARS-CoV-2 neutralizing antibodies. Our objective was to investigate the differences in the cellular response in old and young people after the SARS-CoV-2 vaccination. Methods: Young (24-53 years, n=20) and old (70-76 years, n=20) healthy subjects vaccinated with BNT162b2 SARS-CoV-2 mRNA vaccine were studied before vaccination, two weeks after the first dose and two months after the second dose. SARS-CoV-2 (spike) specific T cell response, TLR-4 dependent monocyte response and TLR-3 dependent myeloid dendritic cell (DC) response and DC, monocyte and T-cell immunophenotype, were studied by multiparametric flow cytometry. TLR-9 dependent interferon-α (IFNα) production by PBMCs was measured by ELISA and thymic function assayed by sj/β TREC ratio using droplet digital PCR. Results: The SARS-CoV-2 specific T cell response was lower and less polyfunctional in old people. Most of the differences in CD4+ and CD8+ T cell subsets were found in degranulation (CD107a), cytokine (IFN-γ) and cytotoxic (perforin) profile (eg, Memory CD8+ perforin+;p=0.0016). The lower SARS-CoV-2 specific T cell response was associated with lower thymic function levels (eg, Memory CD4+ perforin+, r=0.631;p=0.0001). The vaccination induced a higher activation and proliferation (eg, CM CD4 HLA-DR+ p=0.002, Ki67+ p=0.019) of T cells in young people than in old ones, in addition to a higher level of homing makers to different tissues and inflammatory sites (eg, CD1c mDC integrin β7+ p=0.001, intermediate monocytes CCR2+ p=0.0003) in DCs and monocytes. Moreover, after the vaccination, old subjects showed a higher production of proinflammatory cytokines by monocytes in response to LPS (eg, IL6+;p=0.015), while young people showed a higher production of IFNα by plasmacytoid DCs after CpG-A stimulation (p=0.0009). Conclusion: The magnitude and polyfunctionality of SARS-CoV-2 specific T cell response is lower in old people, associated to a lower thymic function. In old people, the vaccination induced less immune activation and homing and the myeloid TLR-dependent response is directed towards a proinflammatory response, while in young people prevails IFNα production, related to a more effective antiviral response. These results support the additional boosting strategies in this vulnerable population.
ABSTRACT
Background: COVID-19 is a severe respiratory disease caused by the SARS-CoV-2 that manifests severely in a high number of patients, leading to hospitalization of many of them and in the worst case to death. Recent studies have shown a high incidence of thrombotic complications in these patients, especially in those with poor prognosis, and confer special interest to D-dimer as an indicator of poor prognosis. However, the diagnostic value of D-dimer is limited by the long analysis times and that it only reflects the final part of the physiological process of hemostasis. Therefore, the identification of other parameters is needed to allow a rapid and reliable characterization of the hemostatic status of the patient. Viscoelastic testing allows a global analysis of coagulation and have already proven their usefulness in the study of other infectious diseases. The application of viscoelastic tests in COVID-19 patients would therefore be very useful to quickly determine the hemostatic status of patients and thus identify predictors of poor prognosis. Aims: To characterize the hemostatic status of COVID-19 patients with standard and viscoelastic testings, and identification of poor prognosis variables. Methods: Prospective, observational, single-centre study. A total of 50 patients requiring hospitalization were included in the study. The next-generation viscoelastic testing "Quantra Hemostasis Analyzer" (HemoSonics) was used to determine the coagulation profile of patients. Blood samples at the time of hospitalization were taken to determine the parameters reported by Quantra (QStat and QPlus cartridges). Correlation study using a heat map of our Spearman partial correlation matrix with a confidence interval of 95%. Results: As described, a high percentage of COVID-19 patients admitted to hospital showed increased levels of fibrinogen (81.6%), D-dimer (61.9%), IL-6 (70.3%) and increased clot stiffness measured by CS, FCS and PCS parameters (63.6%), while clotting times were normal in almost 100% of patients. Age (>65 years), together with elevated levels of D-dimer, LDH and clot firmness were associated with the presence of an adverse event during admission, including the need for mechanical ventilation, ICU admission or death (p=0.007/0.030/0.010/0.002). Increased D-dimer levels were significantly recurrent in patients >65 years (p=0.031). A significant difference was observed between the median of these parameters between patients who experienced an adverse event and those who did not: fibrinogen (750 vs 532, p=0.010), D-dimer (779 vs 560, p=0.005), LDH (309 vs 227, p=0.027), CTH (131.5 vs 123, p=0.042), CS (38.15 vs 25, p=0.042), PCS (30.85 vs 20.7, p=0.042) and FCS (7.45 vs 3.9, p=0.027). Multiple correlation study using HeatMap representation revealed independence between clot firmness, age, LDH and D-dimer levels. Summary/Conclusion: The study of global hemostatic status using Quantra can be a powerful tool for the analysis of COVID-19 patients at admission and thereby predict risk by identifying markers of poor prognosis. Increased levels of parameters measuring clot stiffness are associated with the presence of an adverse event in patients and can be considered as new independent prognostic markers.