Therapy modulates the response to T cell epitopes over the spectrum of tuberculosis infection.

BACKGROUND: Identifying stage-specific antigens is essential for developing tuberculosis (TB) diagnostics and vaccines. In a low TB endemic country, we characterized, the Mycobacterium tuberculosis (Mtb)-specific immune response to a pool of Mtb-derived epitopes (ATB116), demonstrated as associated with TB disease. METHODS: In this prospective observational cross-sectional study, we enrolled healthy donors (HD), subjects with TB disease, and TB infection (TBI) at baseline and therapy completion. T-cell response after whole blood stimulation with the peptide pools was characterized by ELISA, flow cytometry, and multiplex assay. RESULTS: ATB116-specific IFN-γ response (by ELISA) significantly associates with Mtb regardless of infection/disease (p < 0.0001) and decreases during TB therapy (p = 0.0002). Flow cytometry confirms that ATB116-specific CD4+ T-cell response associated with Mtb regardless of infection/disease (p < 0.0001) and shows a significantly higher frequency of IFN-γ/IL-2 and central memory T-cells in TBI compared to TB (p = 0.016; p = 0.0242, respectively). CD4+ T cell-specific response decreases after TB therapy completion. The antigen-specific CD8+ T-cell response mirrors the CD4+ response. Finally, the multiplex assay analysis showed that ATB116 induces several immune factors in both TB and TBI. CONCLUSION: We characterized the immune response to Mtb peptide pools that is modulated by TB therapy. These results are important for our understanding of TB immunopathogenesis and vaccine design.

The Drug Susceptibility of Non-Tuberculous Mycobacteria (NTM) in a Referral Hospital in Rome from 2018 to 2023.

Background: The treatment of non-tuberculous mycobacterial (NTM) infections is challenging because of the difficulty in obtaining phenotypic (pDST) and/or molecular (mDST) drug susceptibility testing and the need of a multi-drug regimen. Objectives: The objective was to describe the in vitro susceptibility patterns of various NTM species through an analysis of susceptibility results obtained on isolates collected between 2018 and 2023. Methods: Species identification and mutations in rrs or rrl genes (mDST) were identified by a line probe assay, while the pDST was performed by broth microdilution and interpreted according to CLSI criteria. Results: We analysed 337 isolates of NTM belonging to 15 species/subspecies. The Mycobacterium avium complex (MAC) was the most common (62%); other species identified included M. gordonae (11%), M. kansasii (5%), the M. abscessus complex (8%), M. chelonae (6%), and M. fortuitum (2%). The results of pDST (claritromycin and amikacin) and mDST (rrl and rrs genes) on 66 NTM strains showed that while wild-type rrl and rrs occurred in 86.3% and 94% strains, respectively, the pDST showed 88% sensitivity for clarithromycin and 57.5% for amikacin. The main incongruity was observed for macrolides. Conclusions: Most NTM are likely to be susceptible to macrolides and aminoglycosides. The molecular identification of resistant genotypes is accurate and strongly recommended for optimal patient management.

Detection of Mycobacterium tuberculosis DNA in CD34+ peripheral blood mononuclear cells of adults with tuberculosis infection and disease.

OBJECTIVES: To investigate whether Mycobacterium tuberculosis (Mtb) DNA is detected in peripheral blood mononuclear cells (PBMC) of subjects with tuberculosis (TB) or TB infection (TBI) living in a low-burden country. METHODS: We prospectively enrolled 57 patients with TB, 41 subjects with TBI, and 39 controls in Rome, Italy. PBMC were isolated, cluster of differentiation (CD)34+ and CD34- cells were immunomagnetic separated, DNA was extracted, and digital polymerase chain reaction for IS6110 and rpoB sequences was used to detect Mtb DNA in PBMC subsets and unfractionated PBMC. RESULTS: We detected Mtb DNA at a low copy number in CD34+ cells in 4o f 30 (13%) patients with TB, 2 of 24 (8%) subjects with TBI, and 1 of 24 (4%) controls. Mtb DNA was detected in unfractionated PBMC in 3 of 51 (6%) patients with TB, 2 of 38 (5%) subjects with TBI, and 2 of 36 (6%) controls. In CD34- cells, only 1 of 31 (3%) subjects with TBI tested positive for Mtb DNA. CONCLUSIONS: Mtb DNA was detected at low frequencies and levels in the PBMC of subjects with TBI and donors with TB living in a low-burden country. In particular, Mtb DNA was detected more frequently in CD34+ cells, supporting the hypothesis that these cells may represent a Mtb niche. This finding informs biological understanding of Mtb pathogenesis and may support the development of a microbial blood biomarker for Mtb infection.

Implementation of Whole Genome Sequencing of Tuberculosis Isolates in a Referral Center in Rome: Six Years' Experience in Characterizing Drug-Resistant TB and Disease Transmission.

Over the past years, Tuberculosis (TB) control strategies have been effective in reducing drug-resistant (DR) TB globally; however, a wider implementation of new diagnostic strategies, such as Whole genome sequencing (WGS), would be critical for further improvement. The aim of this study, based on WGS of Mycobacterium tuberculosis (MTB) strains isolated in a TB referral center over 6 years, was to evaluate the efficacy of this methodology in improving therapy guidance for clinicians and in improving the understanding of the epidemiology of TB transmission. WGS was performed in addition to pDST on 1001 strains consecutively isolated between January 2016 and December 2021; the results allowed us to improve the quality of data on resistance and to identify possible clusters of transmission. Prediction of rifampicin-resistant (RR) or multi-drug-resistant TB strains (MDR-TB, defined as resistance to at least rifampicin and isoniazid) was obtained for 50 strains (5%). Mutations predictive of an MDR isolate were further characterized, and Ser450Leu and Ser315Thr were found to be the most frequent mutations in rpoB and katG genes, respectively. Discordances between WGS and phenotypic drug susceptibility testing (pDST) were found in few strains, and their impact on clinical decisions and outcome was addressed. The introduction of WGS in our Institute improved our diagnostic routine, allowing accurate patient management, and was a valid instrument for epidemiological investigations and infection control.

Alternative biomarkers of tuberculosis infection in patients with immune-mediated inflammatory diseases.

Introduction: IFN-γ release assays (IGRAs) are one of the referral tests for diagnosing tuberculosis infection (TBI). To improve IGRAs accuracy, several markers have been investigated. Patients with immune-mediated inflammatory diseases (IMID), taking biological drugs, have a higher risk to progress to TB-disease compared to the general population. In several guidelines, annual TBI screening is recommended for patients undergoing biological therapy. Aim of this study was to investigate, within the QuantiFERON-TB-Plus (QFT-Plus) platform, if beside IFN-γ, alternative biomarkers help to diagnose TBI-IMID patients. Methods: We enrolled 146 subjects: 46 with TB disease, 20 HD, 35 with TBI and 45 with TBI and IMID. Thirteen IMID subjects with a QFT-Plus negative result were diagnosed as TBI based on radiological evidence of TBI. We evaluated the IP-10 level in response to TB1 and TB2 peptides of QFT-Plus assay and we compared these results with the standardized assay based on IFN-γ. Multiplex immune assay was performed on plasma from TB1 and TB2 tubes and results were analyzed by a gradient boosting machine (GBM) as learning technique. Results: TBI-IMID showed a significant decreased IP-10 level in response to TB1 and TB2 stimulation compared to TBI-NO IMID (p < 0.0001 and p = 0.0002). The TBI-IMID showed a moderate agreement between the IP-10-based assay and QFT-Plus scores. In TBI-IMID, QFT-Plus showed 70% sensitivity for TBI detection whereas the IP-10-based assay reached 61%. Tests combination increased the sensitivity for TBI diagnosis up to 77%. By a GBM, we explored alternative biomarkers for diagnosing TBI in IMID population reaching 89% sensitivity. In particular, the signature based on IL-2, IP-10, and IL-9 detection was associated with TB status (infection/disease). However, by applying the cut-off identified by ROC analysis, comparing TB and TBI with the HD group, within the IMID population, we did not improve the accuracy for TBI-diagnosis. Similarly, this signature did not improve TBI diagnosis in IMID with radiological evidence of TBI but negative QFT-Plus score. Discussion: To develop alternative strategies for TBI immune-diagnosis, future studies are needed to evaluate the memory response of TBI defined by radiological tools. These results may help in tuberculosis management of patients taking lifelong immune-suppressive drugs.

Utility of Liver Biopsy in the Diagnosis and Management of Possible Drug-Induced Liver Injury in Patients Receiving Antituberculosis Therapy: A Retrospective Study.

BACKGROUND: Drug-induced liver injury (DILI) secondary to ATT treatment (TB-DILI) is reported in 2-28% of patients. We present here a series of clinical cases of suspected DILI arising during antituberculosis treatment, studied with the aid of liver biopsy. METHODS: this was a retrospective descriptive study including 10 tuberculosis patients who underwent liver biopsy for suspected TB-DILI at the "Lazzaro Spallanzani" Institute from 2017 to 2022. RESULTS: Ten patients who underwent LB were extracted from the database and included in the retrospective study cohort. According to the clinical classification, eight patients had hepatocellular liver injury, one patient had cholestatic injury, and another had mixed-type injury. Histopathological diagnosis revealed liver damage due to DILI in 5/10 (50%) cases. In one case, liver biopsy showed necrotizing granulomatous hepatitis. CONCLUSIONS: Severe and persistent elevation of hepatic transaminases, hepatic cholestasis despite discontinuation of therapy, and other suspected hepatic conditions are indications for liver biopsy, which remains a valuable tool in the evaluation of selected tuberculosis patients with suspected DILI for many reasons. However, the decision to perform a liver biopsy should be based on clinical judgment, considering the benefits and risks of the procedure.

Diagnosis of Tuberculosis in a Case of Chronic Urticaria following Omalizumab Therapy.

In Italy, tuberculosis (TB) incidence in the last decade has remained constant at under 10 cases/100,000 inhabitants. In the Philippines, TB annual incidence is greater than 500 cases/100,000 inhabitants. Omalizumab is a humanized anti-IgE monoclonal antibody approved for the treatment of chronic spontaneous urticaria. We report the case of a 32-year-old Filipino woman who suffered from chronic urticaria, treated with topic steroids since June 2022 and systemic steroids for 2 weeks. In November 2022, she started omalizumab therapy at a monthly dose of 300 mg; she was not screened for TB infection. In the same month, a left laterocervical lymphadenopathy arose, which worsened in February 2023 (diameter: 3 cm). The patient recovered in April 2023 in INMI "Lazzaro Spallanzani" in Rome for suspected TB. Chest CT showed a "tree in bud" pattern at the upper-right pulmonary lobe. The patient tested positive for lymph node biopsy molecular tuberculosis. The patient started standard antituberculosis therapy. She discontinued omalizumab. To our knowledge, this is the second diagnosed TB case during omalizumab treatment, which suggests that attention should be paid to the known risk of TB during biotechnological treatments. Even if current guidelines do not recommend screening for TB before starting anti-IgE therapy, further data should be sought to assess the relationship between omalizumab treatment and active TB. Our experience suggests that screening for TB should be carried out in patients from highly tuberculosis-endemic countries before starting omalizumab therapy.

Identification of circulating monocytes as producers of tuberculosis disease biomarker C1q.

Tuberculosis (TB) is a prevalent disease causing an estimated 1.6 million deaths and 10.6 million new cases annually. Discriminating TB disease from differential diagnoses can be complex, particularly in the field. Increased levels of complement component C1q in serum have been identified as a specific and accessible biomarker for TB disease but the source of C1q in circulation has not been identified. Here, data and samples previously collected from human cohorts, a clinical trial and a non-human primate study were used to identify cells producing C1q in circulation. Cell subset frequencies were correlated with serum C1q levels and combined with single cell RNA sequencing and flow cytometry analyses. This identified monocytes as C1q producers in circulation, with a pronounced expression of C1q in classical and intermediate monocytes and variable expression in non-classical monocytes.

Recovery from Triple Infection with SARS-CoV-2, RSV and Influenza virus: A case report.

The overall probability of infection with RSV, influenza virus, or SARS-CoV-2 in the general population is assessed as high by the ECDC. A high level of respiratory virus circulation increases hospitalizations and places significant pressure on healthcare systems. Here we describe the case of a 52-year-old woman who recovered from pneumonia with a triple infection with SARS-CoV-2, RSV, and Influenza virus. We suggest searching for antigenic or molecular detection of VSR and influenza viruses, together with SARS-CoV-2, in patients with respiratory symptoms during this epidemic period, whereas all three viruses are present right now.

Evolution of SARS-CoV-2 variants of concern over a period of Delta and Omicron cocirculation, among patients hospitalized for COVID-19 in an Italian reference hospital: Impact on clinical outcomes.

Despite the higher transmissibility of Omicron Variant of Concern (VOC), several reports have suggested lower risk for hospitalization and severe outcomes compared to previous variants of SARS-CoV-2. This study, enrolling all COVID-19 adults admitted to a reference hospital who underwent both the S-gene-target-failure test and VOC identification by Sanger sequencing, aimed to describe the evolving prevalence of Delta and Omicron variants and to compare the main in-hospital outcomes of severity, during a trimester (December 2021 to March 2022) of VOCs' cocirculation. Factors associated with clinical progression to noninvasive ventilation (NIV)/mechanical ventilation (MV)/death within 10 days and to MV/admission to intensive care unit (ICU)/death within 28 days, were investigated through multivariable logistic regressions. Overall, VOCs were: Delta n = 130/428, Omicron n = 298/428 (sublineages BA.1 n = 275 and BA.2 n = 23). Until mid-February, Delta predominance shifted to BA.1, which was gradually displaced by BA.2 until mid-March. Participants with Omicron VOC were more likely to be older, fully vaccinated, with multiple comorbidities and to have a shorter time from symptoms' onset, and less likely to have systemic symptoms and respiratory complications. Although the need of NIV within 10 days and MV within 28 days from hospitalization and the admission to ICU were less frequent for patients with Omicron compared to those with Delta infections, mortality was similar between the two VOCs. In the adjusted analysis, multiple comorbidities and a longer time from symptoms' onset predicted 10-day clinical progression, while complete vaccination halved the risk. Multimorbidity was the only risk factor associated with 28-day clinical progression. In our population, in the first trimester of 2022, Omicron rapidly displaced Delta in COVID-19 hospitalized adults. Clinical profile and presentation differed between the two VOCs and, although Omicron infections showed a less severe clinical picture, no substantial differences for clinical progression were found. This finding suggests that any hospitalization, especially in more vulnerable individuals, may be at risk for severe progression, which is more related to the underlying frailty of patients than to the intrinsic severity of the viral variant.

The role of integrated psychological support in breast cancer patients: a randomized monocentric prospective study evaluating the Fil-Rouge Integrated Psycho-Oncological Support (FRIPOS) program.

PURPOSE: This study examined the effects of Fil-Rouge Integrated Psycho-Oncological Support (FRIPOS) in a group of women with breast cancer compared with a group receiving treatment as usual (TAU). METHODS: The research design was a randomized, monocentric, prospective study with three time points of data collection: after the preoperative phase (T0), in the initial phase of treatments (T1), and 3 months after the start of treatments (T2). The FRIPOS group (N = 103) and the TAU group (N = 79) completed a sociodemographic questionnaire, the Symptom Checklist-90-R (SCL-90-R) at T0; the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ) C30 and EORTC QLQ-BR23 at T1; and SCL-90-R, EORTC QLQ-C30, and EORTC QLQ-BR23 at T2. RESULTS: A series of independent and paired t tests showed that patients in the FRIPOS group performed better on all scales related to symptomatic manifestations and on some quality of life scales (fatigue, dyspnea, and sleep disturbances) at T2. In addition, a series of ten multiple regressions were performed to predict each SCL subscale at T2 from the SCL score at T0 and the EORTC QLQ-C30 scores at T2. In nine of ten regression models (all except somatization), both FRIPOS group membership and QoL subscale contributed significantly to prediction. CONCLUSIONS: This study suggests that patients in the FRIPOS group have more benefits in emotional, psychological, and collateral symptoms than patients in the TAU group and that these improvements are due to integrated psycho-oncology care.

Sarilumab plus standard of care vs standard of care for the treatment of severe COVID-19: a phase 3, randomized, open-labeled, multi-center study (ESCAPE study).

Background: Among interleukin-6 inhibitors suggested for use in COVID-19, there are few robust evidences for the efficacy of sarilumab. Herein, we evaluated the efficacy and safety of sarilumab in severe COVID-19. Methods: In this phase 3, open-labeled, randomized clinical trial, conducted at 5 Italian hospitals, adults with severe COVID-19 pneumonia (excluding mechanically ventilated) were randomized 2:1 to receive intravenous sarilumab (400 mg, repeatable after 12 h) plus standard of care (SOC) (arm A) or to continue SOC (arm B). Randomization was web-based. As post-hoc analyses, the participants were stratified according to baseline inflammatory parameters. The primary endpoint was analysed on the modified Intention-To-Treat population, including all the randomized patients who received any study treatment (sarilumab or SOC). It was time to clinical improvement of 2 points on a 7-points ordinal scale, from baseline to day 30. We used Kaplan Meier method and log-rank test to compare the primary outcome between two arms, and Cox regression stratified by clinical center and adjusted for severity of illness, to estimate the hazard ratio (HR). The trial was registered with EudraCT (2020-001390-76). Findings: Between May 2020 and May 2021, 191 patients were assessed for eligibility, of whom, excluding nine dropouts, 176 were assigned to arm A (121) and B (55). At day 30, no significant differences in the primary endpoint were found (88% [95% CI 81-94] in arm A vs 85% [74-93], HR 1.07 [0.8-1.5] in arm B; log-rank p = 0.50). After stratifying for inflammatory parameters, arm A showed higher probability of improvement than B without statistical significance in the strata with C reactive protein (CRP) < 7 mg/dL (88% [77-96] vs 79% [63-91], HR 1.55 [0.9-2.6]; log-rank p = 0.049) and in the strata with lymphocytes <870/mmc (90% [79-96]) vs (73% [55-89], HR 1.53 [0.9-2.7]; log-rank p = 0.058). Overall, 39/121 (32%) AEs were reported in arm A and 14/55 (23%) in B (p = 0.195), while serious AEs were 22/121 (18%) and 7/55 (11%), respectively (p = 0.244). There were no treatment-related deaths. Interpretation: The efficacy of sarilumab in severe COVID-19 was not demonstrated both in the overall and in the stratified for severity analysis population. Exploratory analyses suggested that subsets of patients with lower CRP values or lower lymphocyte counts might have had benefit with sarilumab treatment, but this finding would require replication in other studies. The relatively low rate of concomitant corticosteroid use, could partially explain our results. Funding: This study was supported by INMI "Lazzaro Spallanzani" Ricerca Corrente Linea 1 on emerging and reemerging infections, funded by Italian Ministry of Health.

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.

Update of drug-resistant tuberculosis treatment guidelines: A turning point.

In December 2022 World Health Organization released a new treatment for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) guideline. The main novelty of this update is two new recommendations (i) a 6-month treatment regimen composed of bedaquiline, pretomanid, linezolid (600 mg), and moxifloxacin (BPaLM) is recommended in place of the 9-month or longer (18-month) regimens in MDR/RR-TB patients, now including extensive pulmonary TB and extrapulmonary TB (except TB involving central nervous system, miliary TB and osteoarticular TB); (ii) the use of the 9-month all-oral regimen rather than longer (18-months) regimen is suggested in patients with MDR/RR-TB and in whom resistance to fluoroquinolones has been excluded. Longer (18-month) treatments remain a valid option in all cases in which shorter regimens cannot be implemented due to intolerance, drug-drug interactions, extensively drug-resistant tuberculosis, extensive forms of extrapulmonary TB, or previous failure. The new guidelines represent a milestone in MDR/RR-TB treatment landscape, setting the basis for a shorter, all-oral, more acceptable, equitable, and patient-centered model for MDR/RR-TB management. However, some challenges remain to be addressed to allow full implementation of the new recommendations.

Proteomic analysis identifies a signature of disease severity in the plasma of COVID-19 pneumonia patients associated to neutrophil, platelet and complement activation.

Most patients infected with SARS-CoV-2 display mild symptoms with good prognosis, while 20% of patients suffer from severe viral pneumonia and up to 5% may require intensive care unit (ICU) admission due to severe acute respiratory syndrome, which could be accompanied by multiorgan failure.Plasma proteomics provide valuable and unbiased information about disease progression and therapeutic candidates. Recent proteomic studies have identified molecular changes in plasma of COVID-19 patients that implied significant dysregulation of several aspects of the inflammatory response accompanied by a general metabolic suppression. However, which of these plasma alterations are associated with disease severity remains only partly characterized.A known limitation of proteomic studies of plasma samples is the large difference in the macromolecule abundance, with concentration spanning at least 10 orders of magnitude. To improve the coverage of plasma contents, we performed a deep proteomic analysis of plasma from 10 COVID-19 patients with severe/fatal pneumonia compared to 10 COVID-19 patients with pneumonia who did not require ICU admission (non-ICU). To this aim, plasma samples were first depleted of the most abundant proteins, trypsin digested and peptides subjected to a high pH reversed-phase peptide fractionation before LC-MS analysis.These results highlighted an increase of proteins involved in neutrophil and platelet activity and acute phase response, which is significantly higher in severe/fatal COVID-19 patients when compared to non-ICU ones. Importantly, these changes are associated with a selective induction of complement cascade factors in severe/fatal COVID-19 patients. Data are available via ProteomeXchange with identifier PXD036491. Among these alterations, we confirmed by ELISA that higher levels of the neutrophil granule proteins DEFA3 and LCN2 are present in COVID-19 patients requiring ICU admission when compared to non-ICU and healthy donors.Altogether, our study provided an in-depth view of plasma proteome changes that occur in COVID-19 patients in relation to disease severity, which can be helpful to identify therapeutic strategies to improve the disease outcome.

Evaluation of the immunomodulatory effects of interleukin-10 on peripheral blood immune cells of COVID-19 patients: Implication for COVID-19 therapy.

Objective: Several therapies with immune-modulatory functions have been proposed to reduce the overwhelmed inflammation associated with COVID-19. Here we investigated the impact of IL-10 in COVID-19, through the ex-vivo assessment of the effects of exogenous IL-10 on SARS-CoV-2-specific-response using a whole-blood platform. Methods: Two cohorts were evaluated: in "study population A", plasma levels of 27 immune factors were measured by a multiplex (Luminex) assay in 39 hospitalized "COVID-19 patients" and 29 "NO COVID-19 controls" all unvaccinated. In "study population B", 29 COVID-19 patients and 30 NO COVID-19-Vaccinated Controls (NO COVID-19-VCs) were prospectively enrolled for the IL-10 study. Whole-blood was stimulated overnight with SARS-COV-2 antigens and then treated with IL-10. Plasma was collected and used for ELISA and multiplex assay. In parallel, whole-blood was stimulated and used for flow cytometry analysis. Results: Baseline levels of several immune factors, including IL-10, were significantly elevated in COVID-19 patients compared with NO COVID-19 subjects in "study population A". Among them, IL-2, FGF, IFN-γ, and MCP-1 reached their highest levels within the second week of infection and then decreased. To note that, MCP-1 levels remained significantly elevated compared with controls. IL-10, GM-CSF, and IL-6 increased later and showed an increasing trend over time. Moreover, exogenous addition of IL-10 significantly downregulated IFN-γ response and several other immune factors in both COVID-19 patients and NO COVID-19-VCs evaluated by ELISA and a multiplex analysis (Luminex) in "study population B". Importantly, IL-10 did not affect cell survival, but decreased the frequencies of T-cells producing IFN-γ, TNF-α, and IL-2 (p<0.05) and down-modulated HLA-DR expression on CD8+ and NK cells. Conclusion: This study provides important insights into immune modulating effects of IL-10 in COVID-19 and may provide valuable information regarding the further in vivo investigations.

Identification of HLA-E Binding Mycobacterium tuberculosis-Derived Epitopes through Improved Prediction Models.

Tuberculosis (TB) remains one of the deadliest infectious diseases worldwide, posing great social and economic burden to affected countries. Novel vaccine approaches are needed to increase protective immunity against the causative agent Mycobacterium tuberculosis (Mtb) and to reduce the development of active TB disease in latently infected individuals. Donor-unrestricted T cell responses represent such novel potential vaccine targets. HLA-E-restricted T cell responses have been shown to play an important role in protection against TB and other infections, and recent studies have demonstrated that these cells can be primed in vitro. However, the identification of novel pathogen-derived HLA-E binding peptides presented by infected target cells has been limited by the lack of accurate prediction algorithms for HLA-E binding. In this study, we developed an improved HLA-E binding peptide prediction algorithm and implemented it to identify (to our knowledge) novel Mtb-derived peptides with capacity to induce CD8+ T cell activation and that were recognized by specific HLA-E-restricted T cells in Mycobacterium-exposed humans. Altogether, we present a novel algorithm for the identification of pathogen- or self-derived HLA-E-presented peptides.

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.

Timing and Outcomes of Noninvasive Ventilation in 307 ARDS COVID-19 Patients: An Observational Study in an Italian Third Level COVID-19 Hospital.

Background and Objectives: Background: Coronavirus disease 2019 (COVID-19) is a novel cause of Acute Respiratory Distress Syndrome (ARDS). Noninvasive ventilation (NIV) is widely used in patients with ARDS across several etiologies. Indeed, with the increase of ARDS cases due to the COVID-19 pandemic, its use has grown significantly in hospital wards. However, there is a lack of evidence to support the efficacy of NIV in patients with COVID-19 ARDS. Materials and Methods: We conducted an observational cohort study including adult ARDS COVID-19 patients admitted in a third level COVID-center in Rome, Italy. The study analyzed the rate of NIV failure defined by the occurrence of orotracheal intubation and/or death within 28 days from starting NIV, its effectiveness, and the associated relative risk of death. The factors associated with the outcomes were identified through logistic regression analysis. Results: During the study period, a total of 942 COVID-19 patients were admitted to our hospital, of which 307 (32.5%) presented with ARDS at hospitalization. During hospitalization 224 (23.8%) were treated with NIV. NIV failure occurred in 84 (37.5%) patients. At 28 days from starting NIV, moderate and severe ARDS had five-fold and twenty-fold independent increased risk of NIV failure (adjusted odds ratio, aOR = 5.01, 95% CI 2.08−12.09, and 19.95, 95% CI 5.31−74.94), respectively, compared to patients with mild ARDS. A total of 128 patients (13.5%) were admitted to the Intensive Care Unit (ICU). At 28-day from ICU admission, intubated COVID-19 patients treated with early NIV had 40% lower mortality (aOR 0.60, 95% CI 0.25−1.46, p = 0.010) compared with patients that underwent orotracheal intubation without prior NIV. Conclusions: These findings show that NIV failure was independently correlated with the severity category of COVID-19 ARDS. The start of NIV in COVID-19 patients with mild ARDS (P/F > 200 mmHg) appears to increase NIV effectiveness and reduce the risk of orotracheal intubation and/or death. Moreover, early NIV (P/F > 200 mmHg) treatment seems to reduce the risk of ICU mortality at 28 days from ICU admission.