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Biology subjects

Hultquist, J.

Publications and source records attributed to Hultquist, J..

2 recordsLinked to original sources

Global siRNA Screen Reveals Critical Human Host Factors of SARS-CoV-2 Multicycle Replication

Defining the subset of cellular factors governing SARS-CoV-2 replication can provide critical insights into viral pathogenesis and identify targets for host-directed antiviral therapies. While a number of genetic screens have previously reported SARS-CoV-2 host dependency factors, these approaches relied on utilizing pooled genome-scale CRISPR libraries, which are biased towards the discovery of host proteins impacting early stages of viral replication. To identify host factors involved throughout the SARS-CoV-2 infectious cycle, we conducted an arrayed genome-scale siRNA screen. Resulting data were integrated with published datasets to reveal pathways supported by orthogonal datasets, including transcriptional regulation, epigenetic modifications, and MAPK signalling. The identified proviral host factors were mapped into the SARS-CoV-2 infectious cycle, including 27 proteins that were determined to impact assembly and release. Additionally, a subset of proteins were tested across other coronaviruses revealing 17 potential pan-coronavirus targets. Further studies illuminated a role for the heparan sulfate proteoglycan perlecan in SARS-CoV-2 viral entry, and found that inhibition of the non-canonical NF-kB pathway through targeting of BIRC2 restricts SARS-CoV-2 replication both in vitro and in vivo. These studies provide critical insight into the landscape of virus-host interactions driving SARS-CoV-2 replication as well as valuable targets for host-directed antivirals.

systems biology↗

IL-10 driven memory T cell survival and Tfh differentiation promote HIV persistence

Mechanisms regulating HIV persistence are complex and not well understood. Increased IL-10 levels were positively associated with HIV reservoir in blood and lymph nodes (LN) of treated HIV aviremic individuals. In LNs, B cells, regulatory T cells, follicular T helper cells (Tfh), monocytes and macrophages contributed to the frequencies of IL10+ cells. Cells with HIV DNA in LNs were in close proximity to IL-10+ cells and/or had the active form of STAT3, the transcription downstream of IL-10. Gene signatures and proteins associated to cell survival, Co-inhibitory receptors expression, maintenance of memory T cells, immune metabolism and Tfh frequencies were all modulated by IL-10 and associated with HIV reservoir persistence. In vitro, STAT3 knockout or neutralization of IL-10, reverted all the aforementioned pathways and resulted in 10-fold decay in HIV reservoir. Collectively, these results provide strong evidence for a pivotal role of IL-10 in HIV persistence, and a potential therapeutic strategy for HIV cure.

immunology↗