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Appendices for STTAR Bioresource COVID-19 Biobanking study. The primary objective of this study is to build a biobank, to understand the clinical characteristics and natural history of COVID-19 infection with the long-term goal of research into improved disease understanding, diagnostic tests and treatments. These appendices include the case report form, informed consent form and online convalescent visit report form related to this study&nbsp

Viruses use a spectrum of immune evasion strategies that enable infection and replication. The acute phase of hepatitis C virus (HCV) infection is characterized by nonspecific and often mild clinical symptoms, suggesting an immunosuppressive mechanism that, unless symptomatic liver disease presents, allows the virus to remain largely undetected. We previously reported that HCV induced the regulatory protein suppressor of cytokine signaling (SOCS)3, which inhibited TNF-α-mediated inflammatory responses. However, the mechanism by which HCV up-regulates SOCS3 remains unknown. Here we show that the HCV protein, p7, enhances both SOCS3 mRNA and protein expression. A p7 inhibitor reduced SOCS3 induction, indicating that p7's ion channel activity was required for optimal up-regulation of SOCS3. Short hairpin RNA and chemical inhibition revealed that both the Janus kinase-signal transducer and activator of transcription (JAK-STAT) and MAPK pathways were required for p7-mediated induction of SOCS3. HCV-p7 expression suppressed TNF-α-mediated IκB-α degradation and subsequent NF-κB promoter activity, revealing a new and functional, anti-inflammatory effect of p7. Together, these findings identify a molecular mechanism by which HCV-p7 induces SOCS3 through STAT3 and ERK activation and demonstrate that p7 suppresses proinflammatory responses to TNF-α, possibly explaining the lack of inflammatory symptoms observed during early HCV infection.-Convery, O., Gargan, S., Kickham, M., Schroder, M., O'Farrelly, C., Stevenson, N. J. The hepatitis C virus (HCV) protein, p7, suppresses inflammatory responses to tumor necrosis factor (TNF)-α via signal transducer and activator of transcription (STAT)3 and extracellular signal-regulated kinase (ERK)-mediated induction of suppressor of cytokine signaling (SOCS)3.

Toll-like Receptors (TLR)s are an essential class of Pattern Recognition Receptors (PRR)s used by the innate immune system to recognise conserved microbial motifs which are characteristic of invading pathogens. Activation of TLRs initiates signalling cascades resulting in the activation of transcription factors such as NF-κB and members of the interferon regulatory factor (IRF) family which regulate gene expression and mediate an immune response to the pathogen. Dysregulation of TLR-signalling can result in inflammatory and autoimmune diseases and for this reason they are subject to tight regulation. This study demonstrates Cactin to be a novel negative regulator of TLR-signalling pathways. Overexpression of Cactin inhibits activation of NF-κB whilst suppressed expression of Cactin leads to stronger and more prolonged activation of NF-κB in response to LPS. The expression of Cactin is regulated by NF-κB, thus representing a novel negative feedback mechanism for suppression of the inflammatory response. Cactin protein is stabilised due to phosphorylation in cells treated with the pro-inflammatory cytokine IL-1β. Similarly, the stabilisation of Cactin was observed in response to the TLR ligands LPS and Poly(I:C). Cactin also negatively regulates the activation of IRF3 and IRF7 and suppression of endogenous Cactin augments Poly(I:C)-mediated IFNβ induction. Cactin localises to the nucleus by virtue of two nuclear localisation sequences (NLS)s and its nuclear expression is essential for manifesting its inhibitory effects. Within the nucleus Cactin inhibits the DNA-binding activity of the NF-κB subunit p65. Suppression of endogenous Cactin leads to increased binding of IRF3 to the IFNβ promoter, though Cactin had no effect on IRF3 phosphorylation or translocation. This indicates that Cactin also targets IRF3 at the level of DNA binding. Furthermore, Cactin negatively regulates IRF7-mediated IFNα induction and affects the protein stability of IRF7. Notably, these inhibitory effects are transcription factor specific as Cactin positively regulates the activation of AP-1 subunit c-Jun, demonstrating that Cactin can differentially regulate transcription factor activation. A number of Cactin-interacting proteins were also identified in this study. Interestingly Cactin interacts with a nuclear member of the IκB family, IκBL. Cactin and IκBL show very similar nuclear expression patterns and exhibit similar negative regulatory effects on NF-κB, IRF3 and IRF7. However, these two proteins function independently to inhibit the activation of these transcription factors. In summary this study highlights Cactin as a novel regulator of TLR signalling pathways by regulating the ability of specific transcription factors to bind to their cognate DNA sequences and induce transcription.