Mapping immunodominant sites on the MERS-CoV spike glycoprotein targeted by infection-elicited antibodies in humans.

Middle East respiratory syndrome coronavirus (MERS-CoV) first emerged in 2012 and causes human infections in endemic regions. Vaccines and therapeutics in development against MERS-CoV focus on the spike (S) glycoprotein to prevent viral entry into target cells. These efforts are limited by a poor understanding of antibody responses elicited by infection. Here, we analyze S-directed antibody responses in plasma collected from MERS-CoV-infected individuals. We observe that binding and neutralizing antibodies peak 1-6 weeks after symptom onset/hospitalization, persist for at least 6 months, and neutralize human and camel MERS-CoV strains. We show that the MERS-CoV S1 subunit is immunodominant and that antibodies targeting S1, particularly the receptor-binding domain (RBD), account for most plasma neutralizing activity. Antigenic site mapping reveals that plasma antibodies frequently target RBD epitopes, whereas targeting of S2 subunit epitopes is rare. Our data reveal the humoral immune responses elicited by MERS-CoV infection, which will guide vaccine and therapeutic design.

Mapping immunodominant sites on the MERS-CoV spike glycoprotein targeted by infection-elicited antibodies in humans.

Middle-East respiratory syndrome coronavirus (MERS-CoV) first emerged in 2012 and causes human infections in endemic regions. Most vaccines and therapeutics in development against MERS-CoV focus on the spike (S) glycoprotein to prevent viral entry into target cells. These efforts, however, are limited by a poor understanding of antibody responses elicited by infection along with their durability, fine specificity and contribution of distinct S antigenic sites to neutralization. To address this knowledge gap, we analyzed S-directed binding and neutralizing antibody titers in plasma collected from individuals infected with MERS-CoV in 2017-2019 (prior to the COVID-19 pandemic). We observed that binding and neutralizing antibodies peak 1 to 6 weeks after symptom onset/hospitalization, persist for at least 6 months, and broadly neutralize human and camel MERS-CoV strains. We show that the MERS-CoV S1 subunit is immunodominant and that antibodies targeting S1, particularly the RBD, account for most plasma neutralizing activity. Antigenic site mapping revealed that polyclonal plasma antibodies frequently target RBD epitopes, particularly a site exposed irrespective of the S trimer conformation, whereas targeting of S2 subunit epitopes is rare, similar to SARS-CoV-2. Our data reveal in unprecedented details the humoral immune responses elicited by MERS-CoV infection, which will guide vaccine and therapeutic design.

Type I interferon autoantibodies in hospitalized patients with Middle East respiratory syndrome and association with outcomes and treatment effect of interferon beta-1b in MIRACLE clinical trial.

Background: Type I interferons (IFNs) are essential antiviral cytokines induced upon respiratory exposure to coronaviruses. Defects in type I IFN signaling can result in severe disease upon exposure to respiratory viral infection and are associated with worse clinical outcomes. Neutralizing autoantibodies (auto-Abs) to type I IFNs were reported as a risk factor for life-threatening COVID-19, but their presence has not been evaluated in patients with severe Middle East respiratory syndrome (MERS). Methods: We evaluated the prevalence of type I IFN auto-Abs in a cohort of hospitalized patients with MERS who were enrolled in a placebo-controlled clinical trial for treatment with IFN-ß1b and lopinavir-ritonavir (MIRACLE trial). Samples were tested for type I IFN auto-Abs using a multiplex particle-based assay. Results: Among the 62 enrolled patients, 15 (24.2%) were positive for immunoglobulin G auto-Abs for at least one subtype of type I IFNs. Auto-Abs positive patients were not different from auto-Abs negative patients in age, sex, or comorbidities. However, the majority (93.3%) of patients who were auto-Abs positive were critically ill and admitted to the ICU at the time of enrollment compared to 66% in the auto-Abs negative patients. The effect of treatment with IFN-ß1b and lopinavir-ritonavir did not significantly differ between the two groups. Conclusion: This study demonstrates the presence of type I IFN auto-Abs in hospitalized patients with MERS.

Heterogeneity of treatment effect of interferon-ß1b and lopinavir-ritonavir in patients with Middle East respiratory syndrome by cytokine levels.

Animal and human data indicate variable effects of interferons in treating coronavirus infections according to inflammatory status and timing of therapy. In this sub-study of the MIRACLE trial (MERS-CoV Infection Treated with a Combination of Lopinavir-Ritonavir and Interferon ß-1b), we evaluated the heterogeneity of treatment effect of interferon-ß1b and lopinavir-ritonavir versus placebo among hospitalized patients with MERS on 90-day mortality, according to cytokine levels and timing of therapy. We measured plasma levels of 17 cytokines at enrollment and tested the treatment effect on 90-day mortality according to cytokine levels (higher versus lower levels using the upper tertile (67%) as a cutoff point) and time to treatment (≤ 7 days versus > 7 days of symptom onset) using interaction tests. Among 70 included patients, 32 received interferon-ß1b and lopinavir-ritonavir and 38 received placebo. Interferon-ß1b and lopinavir-ritonavir reduced mortality in patients with lower IL-2, IL-8 and IL-13 plasma concentrations but not in patients with higher levels (p-value for interaction = 0.09, 0.07, and 0.05, respectively) and with early but not late therapy (p = 0.002). There was no statistically significant heterogeneity of treatment effect according to other cytokine levels. Further work is needed to evaluate whether the assessment of inflammatory status can help in identifying patients with MERS who may benefit from interferon-ß1b and lopinavir-ritonavir. Trial registration: This is a sub-study of the MIRACLE trial (ClinicalTrials.gov number, NCT02845843).

Alterations in the Plasma Proteome Induced by SARS-CoV-2 and MERS-CoV Reveal Biomarkers for Disease Outcomes for COVID-19 Patients.

PURPOSE: This study aimed to understand the pathophysiology of host responses to infections caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)/(COVID-19) and Middle East respiratory syndrome coronavirus (MERS-CoV) and to identify proteins for patient stratification with different grades of illness severity. PATIENTS AND METHODS: Peripheral blood samples from 43 patients with different grades of COVID-19, 7 MERS-CoV patients admitted to the ICU, and 10 healthy subjects were analyzed using label-free quantitative liquid chromatography-mass spectrometry (LC-MS). RESULTS: We identified 193 and 91 proteins that differed significantly between COVID-19 and MERS-CoV sample groups, respectively, and 49 overlapped between datasets. Only 10 proteins are diagnostic of asymptomatic cases, 12 are prognostic of recovery from severe illness, and 28 are prognostic of a fatal outcome of COVID-19. These proteins are implicated in virus-specific/related signaling networks. Notable among the top canonical pathways are humoral immunity, inflammation, acute-phase response signaling, liver X receptor/retinoid X receptor (LXR/RXR) activation, coagulation, and the complement system. Furthermore, we confirmed positive viral shedding in 11.76% of 51 additional peripheral blood samples, indicating that caution should be taken to avoid the possible risk of transfusion of infected blood products. CONCLUSION: We identified COVID-19 and MERS-CoV protein panels that have potential as biomarkers and might assist in the prognosis of SARS-CoV-2 infection. The identified markers further our understanding of COVID-19 disease pathophysiology and may have prognostic or therapeutic potential in predicting or managing host cell responses to human COVID-19 and MERS-CoV infections.

Beyond Frontiers: Feasibility and Outcomes of Prolonged Veno-Venous Extracorporeal Membrane Oxygenation in Severe Acute Respiratory Distress Syndrome.

Extracorporeal membrane oxygenation (ECMO) use in acute respiratory failure is increasing. We aim to compare characteristics and outcomes of patients with prolonged (≥21 days) veno-venous (VV) ECMO runs (pECMO), to patients with short (<21 days) VV ECMO runs (sECMO). The observational retrospective single-center study compared patients who received VV ECMO from January 2018 to June 2019 at Prince Mohamed Bin Abdulaziz Center in Riyadh, Saudi Arabia. Forty-three patients were supported with VV ECMO during the study period, of whom 37 are included as six patients were still receiving ECMO at time of data collection: 24 sECMO and 13 pECMO patients. Baseline characteristics and comorbidities were similar except pECMO patients were older and had a lower P/F ratio (61 [58-68] vs. 71[58-85.5], p = 0.05). Survival to hospital discharge (69% vs. 83%, p = 0.32; pECMO vs. sECMO) and 90 day survival (62% vs. 75%, p = 0.413; pECMO vs. sECMO) were similar among groups. At 1 year follow-up, all patients were still alive and independently functioning except for one patient in the pECMO group who required a walking aid related to trauma. In this single-center study, patients requiring pECMO had similar short- and long-term survival to those requiring sECMO duration.

Interferon Beta-1b and Lopinavir-Ritonavir for Middle East Respiratory Syndrome.

BACKGROUND: Whether combined treatment with recombinant interferon beta-1b and lopinavir-ritonavir reduces mortality among patients hospitalized with Middle East respiratory syndrome (MERS) is unclear. METHODS: We conducted a randomized, adaptive, double-blind, placebo-controlled trial that enrolled patients at nine sites in Saudi Arabia. Hospitalized adults with laboratory-confirmed MERS were randomly assigned to receive recombinant interferon beta-1b plus lopinavir-ritonavir (intervention) or placebo for 14 days. The primary outcome was 90-day all-cause mortality, with a one-sided P-value threshold of 0.025. Prespecified subgroup analyses and safety analyses were conducted. Because of the pandemic of coronavirus disease 2019, the data and safety monitoring board requested an unplanned interim analysis and subsequently recommended the termination of enrollment and the reporting of the results. RESULTS: A total of 95 patients were enrolled; 43 patients were assigned to the intervention group and 52 to the placebo group. A total of 12 patients (28%) in the intervention group and 23 (44%) in the placebo group died by day 90. The analysis of the primary outcome, with accounting for the adaptive design, yielded a risk difference of -19 percentage points (upper boundary of the 97.5% confidence interval [CI], -3; one-sided P = 0.024). In a prespecified subgroup analysis, treatment within 7 days after symptom onset led to lower 90-day mortality than use of placebo (relative risk, 0.19; 95% CI, 0.05 to 0.75), whereas later treatment did not. Serious adverse events occurred in 4 patients (9%) in the intervention group and in 10 (19%) in the placebo group. CONCLUSIONS: A combination of recombinant interferon beta-1b and lopinavir-ritonavir led to lower mortality than placebo among patients who had been hospitalized with laboratory-confirmed MERS. The effect was greatest when treatment was started within 7 days after symptom onset. (Funded by the King Abdullah International Medical Research Center; MIRACLE ClinicalTrials.gov number, NCT02845843.).

Left inferior epigastric artery injury in COVID-19 patient. Case report and literature review.

INTRODUCTION: Management of COVID-19 pneumonia cases is a medical challenge. However, the situation becomes worse if the patient has coexisting morbidities or newly developed complications. The study is about managing rectus sheath haematoma (RSH) in a patient with COVID-19 pneumonia. PRESENTATION OF CASE: The patient was a 75-year-old male, presenting with bilateral COVID-19 pneumonia, with pulmonary embolism complications. Therapeutic anticoagulation by subcutaneous Clexane injection was administered. A left rectus haematoma was observed, and the patient fell and underwent haemorrhagic shock. Laparotomy was done for the evacuation of the haematoma. DISCUSSION: Contrast-enhanced computed tomography (CECT) is an essential tool for diagnosing RSH, identifying the source of bleeding, type of haematoma, and compression of the urinary system. CONCLUSION: Surgical management of RSH in COVID-19 patients is superior to interventional radiology during the rush pandemic period.

Treatment of Middle East respiratory syndrome with a combination of lopinavir/ritonavir and interferon-ß1b (MIRACLE trial): statistical analysis plan for a recursive two-stage group sequential randomized controlled trial.

The MIRACLE trial (MERS-CoV Infection tReated with A Combination of Lopinavir/ritonavir and intErferon-ß1b) investigates the efficacy of a combination therapy of lopinavir/ritonavir and recombinant interferon-ß1b provided with standard supportive care, compared to placebo provided with standard supportive care, in hospitalized patients with laboratory-confirmed MERS. The MIRACLE trial is designed as a recursive, two-stage, group sequential, multicenter, placebo-controlled, double-blind randomized controlled trial. The aim of this article is to describe the statistical analysis plan for the MIRACLE trial. The primary outcome is 90-day mortality. The primary analysis will follow the intention-to-treat principle. The MIRACLE trial is the first randomized controlled trial for MERS treatment. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02845843. Registered on 27 July 2016.