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Svensson Akusjarvi, S.

Publications and source records attributed to Svensson Akusjarvi, S..

3 recordsLinked to original sources

Distinct lipid profile, low-level inflammation and increased antioxidant defense as a signature in HIV-1 elite control status

HIV-1 elite controllers (EC) are a rare but heterogeneous group of HIV-1-infected individuals who are able to suppress viral replication in the absence of antiretroviral therapy. The mechanisms of how EC achieve undetectable viral loads remain unclear. This study aimed to investigate host plasma metabolomics and targeted plasma proteomics in a Swedish HIV-1 cohort including EC and treatment-naive viremic progressors (VP) as well as HIV-negative individuals (HC) to get insights into mechanisms governing EC status. Metabolites belonging to antioxidant defense had higher levels in EC relative to VP while inflammation markers were increased in VP compared to EC. Only four plasma proteins (CCL4, CCL7, CCL20, and NOS3) were increased in EC compared to HC and CCL20/CCR6 axis can play important role. Our study suggests that low-level inflammation and oxidative stress at physiological levels could be important factors contributing to control of viral replication. One Sentence SummaryHIV-1 elite controllers had a distinct lipid profile, reduced inflammation, and increased antioxidant defense that might contribute to elite control status.

microbiology↗

Dysregulation in mTOR/HIF-1 signaling identified by proteo-transcriptomics of SARS-CoV-2 infected cells

How Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infections engage cellular host pathways and innate immunity in infected cells remain largely elusive. We performed an integrative proteo-transcriptomics analysis in SARS-CoV-2 infected HuH7 cells to map the cellular response to the invading virus over time. We identified four pathways, ErbB, HIF-1, mTOR and TNF signaling, among others that were markedly modulated during the course of the SARS-CoV-2 infection in vitro. Western blot validation of the downstream effector molecules of these pathways revealed a significant reduction in activated S6K1 and 4E-BP1 at 72 hours post infection. Unlike other human respiratory viruses, we found a significant inhibition of HIF-1 through the entire time course of the infection, suggesting a crosstalk between the SARS-CoV-2 and the mTOR/HIF-1 signaling. Further investigations are required to better understand the molecular sequelae in order to guide potential therapy in the management of severe COVID-19 patients.

microbiology↗

Chromatin maturation of the HIV-1 provirus in primary resting CD4+ T cells

Human immunodeficiency virus type 1 (HIV-1) infection is a chronic condition, where viral DNA integrates into the genome. Latently infected cells form a persistent, heterogeneous reservoir. The reservoir that reinstates an active replication comprises only cells with intact provirus that can be reactivated. We confirmed that latently infected cells from patients exhibited active transcription throughout the provirus. To find transcriptional determinants, we characterized the establishment and maintenance of viral latency during proviral chromatin maturation in cultures of primary CD4+ T-cells for four months after ex vivo HIV-1 infection. As heterochromatin (marked with H3K9me3 or H3K27me3) gradually stabilized, the provirus became less accessible with reduced activation potential. In a subset of infected cells, active marks (i.e., H3K27ac) remained detectable, even after prolonged proviral silencing. After T-cell activation, the proviral activation occurred uniquely in cells with H3K27ac-marked proviruses. Our observations suggested that, after transient proviral activation, cells were actively returned to latency.

microbiology↗