Risk Factors for Infection and Health Impacts of the COVID-19 Pandemic in People with Autoimmune Diseases (preprint)

Background: People with autoimmune or inflammatory conditions who take immunomodulatory/suppressive medications may have a higher risk of novel coronavirus disease 2019 (COVID-19). Chronic disease care has also changed for many patients, with uncertain downstream consequences. Objective: Assess whether COVID-19 risk is higher among those on immunomodulating or suppressive agents and characterize pandemic-associated changes to care. Design: Longitudinal registry study Participants: 4666 individuals with autoimmune or inflammatory conditions followed by specialists in neurology, rheumatology, cardiology, pulmonology or gastroenterology at Johns Hopkins Measurements: Periodic surveys querying comorbidities, disease-modifying medications, exposures, COVID-19 testing and outcomes, social behaviors, and disruptions to healthcare Results: A total of 265 (5.6%) developed COVID-19 over 9 months of follow-up (April-December 2020). Patient characteristics (age, race, comorbidity, medication exposure) were associated with differences in social distancing behaviors during the pandemic. Glucocorticoid exposure was associated with higher odds of COVID-19 in multivariable models incorporating behavior and other potential confounders (OR: 1.43; 95%CI: 1.08, 1.89). Other medication classes were not associated with COVID-19 risk. Diabetes (OR: 1.72; 95%CI: 1.08, 2.73), cardiovascular disease (OR: 1.68; 95%CI: 1.24, 2.28), and chronic kidney disease (OR: 1.76; 95%CI: 1.04, 2.97) were each associated with higher odds of COVID-19. Pandemic-related disruption to care was common. Of the 2156 reporting pre-pandemic utilization of infusion, mental health or rehabilitative services, 975 (45.2%) reported disruptions. Individuals experiencing changes to employment or income were at highest odds of care disruption. Limitations: Results may not be generalizable to all patients with autoimmune or inflammatory conditions. Information was self-reported. Conclusions: Exposure to glucocorticoids may increase risk of COVID-19 in people with autoimmune or inflammatory conditions. Disruption to healthcare and related services was common. Those with pandemic-related reduced income may be most vulnerable to care disruptions.

Cerebrospinal fluid in COVID-19 neurological complications: no cytokine storm or neuroinflammation. (preprint)

BACKGROUND. Neurological complications occur in COVID-19. We aimed to examine cerebrospinal fluid (CSF) of COVID-19 subjects with neurological complications and determine presence of neuroinflammatory changes implicated in pathogenesis. METHODS. Cross-sectional study of CSF neuroinflammatory profiles from 18 COVID-19 subjects with neurological complications categorized by diagnosis (stroke, encephalopathy, headache) and illness severity (critical, severe, moderate, mild). COVID-19 CSF was compared with CSF from healthy, infectious and neuroinflammatory disorders and stroke controls (n=82). Cytokines (IL-6, TNF-alpha, IFN-gamma, IL-10, IL-12p70, IL-17A), inflammation and coagulation markers (high-sensitivity-C Reactive Protein [hsCRP], ferritin, fibrinogen, D-dimer, Factor VIII) and neurofilament light chain (NF-L), were quantified. SARS-CoV2 RNA and SARS-CoV2 IgG and IgA antibodies in CSF were tested with RT-PCR and ELISA. RESULTS. CSF from COVID-19 subjects showed a paucity of neuroinflammatory changes, absence of pleocytosis or specific increases in pro-inflammatory markers or cytokines (IL-6, ferritin, or D-dimer). Anti-SARS-CoV2 antibodies in CSF of COVID-19 subjects (77%) were observed despite no evidence of SARS-CoV2 viral RNA. A similar increase of pro-inflammatory cytokines (IL-6, TNF-alpha;, IL-12p70) and IL-10 in CSF of COVID-19 and non-COVID-19 stroke subjects was observed compared to controls. CSF-NF-L was elevated in subjects with stroke and critical COVID-19. CSF-hsCRP was present almost exclusively in COVID-19 cases. CONCLUSION. The paucity of neuroinflammatory changes in CSF of COVID-19 subjects and lack of SARS-CoV2 RNA do not support the presumed neurovirulence of SARS-CoV2 or neuroinflammation in pathogenesis of neurological complications in COVID-19. Elevated CSF-NF-L indicates neuroaxonal injury in COVID-19 cases. The role of CSF SARS-CoV2 IgG antibodies is still undetermined.

Inhibitor Binding Modulates Protonation States in the Active Site of SARS-CoV-2 Main Protease (preprint)

The main protease (3CL Mpro) from SARS-CoV-2, the virus that causes COVID-19, is an essential enzyme for viral replication with no human counterpart, making it an attractive drug target. Although drugs have been developed to inhibit the proteases from HIV, hepatitis C and other viruses, no such therapeutic is available to inhibit the main protease of SARS-CoV-2. To directly observe the protonation states in SARS-CoV-2 Mpro and to elucidate their importance in inhibitor binding, we determined the structure of the enzyme in complex with the -ketoamide inhibitor telaprevir using neutron protein crystallography at near-physiological temperature. We compared protonation states in the inhibitor complex with those determined for a ligand-free neutron structure of Mpro. This comparison revealed that three active-site histidine residues (His41, His163 and His164) adapt to ligand binding, altering their protonation states to accommodate binding of telaprevir. We suggest that binding of other -ketoamide inhibitors can lead to the same protonation state changes of the active site histidine residues. Thus, by studying the role of active site protonation changes induced by inhibitors we provide crucial insights to help guide rational drug design, allowing precise tailoring of inhibitors to manipulate the electrostatic environment of SARS-CoV-2 Mpro.