Monocyte Signature Associated with Herpes Simplex Virus Reactivation and Neurological Recovery after Brain Injury.

Rationale: Brain injury induces systemic immunosuppression, increasing the risk of viral reactivations and altering neurological recovery. Objectives: To determine if systemic immune alterations and lung replication of herpesviridae are associated and can help predict outcomes after brain injury. Methods: We collected peripheral blood mononuclear cells in patients with severe brain injury requiring invasive mechanical ventilation. We systematically searched for respiratory herpes simplex virus (HSV) replications in tracheal aspirates. We also performed chromatin immunoprecipitation sequencing, RNA-sequencing, and in vitro functional assays of monocytes and CD4 T cells collected on Day 1 to characterize the immune response to severe acute brain injury. The primary outcome was the Glasgow Outcome Scale Extended at 6 months. Measurements and Main Results: In 344 patients with severe brain injury, lung HSV reactivations were observed in 39% of the 232 patients seropositive for HSV and independently associated with poor neurological recovery at 6 months (hazard ratio, 1.90; 95% confidence interval, 1.08-3.57). Weighted gene coexpression network analyses of the transcriptomic response of monocytes to brain injury defined a module of 721 genes, including PD-L1 and CD80, enriched for the binding DNA motif of the transcriptional factor Zeb2 and whose ontogenic analyses revealed decreased IFN-γ-mediated and antiviral response signaling pathways. This monocyte signature was preserved in a validation cohort and predicted the neurological outcome at 6 months with good accuracy (area under the curve, 0.786; 95% confidence interval, 0.593-0.978). Conclusions: A specific monocyte signature is associated with HSV reactivation and predicts poor recovery after brain injury. The alterations of the immune control of herpesviridae replication are understudied and represent a novel therapeutic target.

[Viral reactivations in intensive care unit: biomarkers of immune dysfunction or true pathogens?] / Réactivations virales en réanimation : biomarqueurs de dysfonctionnement immunitaire ou véritables pathogènes ?

Studies performed in patients considered as immunocompetent and hospitalized in intensive care unit (ICU) have revealed profound immune alterations leading to an increased risk of viral reactivations. In particular, Herpesviridae reactivations (HSV and CMV) have been associated with an increased morbidity and mortality in ICU patients. Early diagnosis of these reactivations is now recommended in ICU patients, but the indications of an antiviral therapy remain to be better defined. Advances in molecular biology now allow us to study the human virome in different biological compartments. Among the more frequent viruses detected in the virome, Torque Teno Virus (TTV) has been shown to be associated to the immunocompetence level of immunocompromised patients at risk of opportunistic viral infections. In organ transplant patients, the TTV proportion in blood increases with the degree of immunosuppression and the risk of secondary infections. It remains to be evaluated in other immune dysfunction settings, such as ICU patients. Human virome modulation, as measured by metagenomics, is a promising tool to investigate immune status in various clinical settings. It could be an innovative marker for personalized care, including the evaluation of immunomodulatory molecules use for the prevention and treatment of infectious complications in ICU patients.

Complete post-mortem data in a fatal case of COVID-19: clinical, radiological and pathological correlations.

A 75-year-old man presented to a French hospital with a 4-day fever after returning from a coronavirus disease-19 (COVID-19) cluster region. A reverse-transcription polymerase chain reaction test was positive for severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) using a nasopharyngeal swab sample. After he returned home and a telephone follow-up, he was found deceased 9 days after first showing symptoms. Whole-body, non-enhanced, post-mortem computed tomography (PMCT) and a forensic autopsy were performed approximately 48 h after death, with sanitary precautions. The PMCT showed bilateral and diffuse crazy-paving lung opacities, with bilateral pleural effusions. Post-mortem virology studies detected the presence of SARS-CoV-2 (B.1 lineage) in the nasopharynx, plasma, lung biopsies, pleural effusion and faeces confirming the persistence of viral ribonucleic acid 48 h after death. Microscopic examination showed that severe lung damage was responsible for his death. The main abnormality was diffuse alveolar damage, associated with different stages of inflammation and fibrosis. This case is one of the first to describe complete post-mortem data for a COVID-19 death and highlights the ability of PMCT to detect severe involvement of the lungs before autopsy in an apparently natural death. The present pathology results are concordant with previously reported findings and reinforce the disease pathogenesis hypothesis of combined viral replication with an inappropriate immune response.

New mechanisms of resistance in virological failure to protease inhibitors: selection of non-described protease, Gag and Gp41 mutations.

OBJECTIVES: To further characterize HIV-1 viruses of patients experiencing unexplained virological failure (VF) on PI-containing regimens, ultradeep sequencing was performed on protease, gag and gp41 genes in patients failing a first-line treatment. METHODS: All naive patients initiating an antiretroviral treatment based on boosted darunavir, atazanavir or lopinavir and experiencing VF without any transmitted drug resistance mutation detected by Sanger sequencing on protease and reverse transcriptase genes were selected. Ultradeep sequencing (IlluminaTM Nextera®) was performed on protease, gag and gp41 genes in plasma before initiation of treatment and at VF to identify emergent mutations. RESULTS: Among the 32 patients included in the study, emergent and previously undescribed mutations in the viral protease gene were identified in five patients at VF: 64M (1 CRF02_AG), 64M/70R with mutation 15V (2 CRF02_AG), 79A (1 CRF06_cpx) and 79A with mutation 15V (1 CRF02_AG). Two patients showed the emergence of R286K in the gag region, outside of cleavage sites (2 CRF02_AG). In the gp41 region, the V321I mutation emerged inside the cytoplasmic tail (1 subtype A and 1 subtype B). All these patients were treated with a darunavir/ritonavir-based regimen. CONCLUSIONS: In some cases of VF to PIs, we observed the emergence of protease, Gag or Gp41 mutations that had not previously been associated with VF or PI resistance. These mutations should be further studied, in particular the 15V/64M/70R pattern in the protease gene identified among CRF02_AG viruses.

HIV-1 protease, Gag and gp41 baseline substitutions associated with virological response to a PI-based regimen.

OBJECTIVES: To assess, at ART initiation, the impact of baseline substitutions in protease, Gag and gp41 regions on the virological response to a first-line PI-based regimen. PATIENTS AND METHODS: One hundred and fifty-four HIV-infected ART-naive patients initiating a PI-based regimen including darunavir (n = 129) or atazanavir (n = 25) were assessed, including 36 experiencing virological failure (VF). Whole pol, gag and gp41 genes were sequenced at ART baseline by ultra-deep sequencing (UDS) using Illumina® technology. Supervised data-mining analyses were performed to identify mutations associated with virological response. Structural analyses were performed to assess the impact of mutations on protease conformation. RESULTS: UDS was successful in 127, 138 and 134 samples for protease, Gag and gp41, respectively (31% subtype B and 38% CRF02_AG). Overall, T4A and S37T mutations in protease were identified as being associated with VF (P = 0.02 and P = 0.005, respectively). Among CRF02_AG sequences, I72M and E21D mutations were associated with VF (P = 0.03 for both). They all induced some conformational changes of some protease side-chain residues located near mutated residues. In Gag, mutations associated with VF were G62D, N315H and Y441S (P = 0.005, P = 0.007 and P = 0.0003, respectively). All were localized outside Gag cleavage sites (G62D, matrix; N315H, capsid; and Y441S, p1). In gp41, the I270T mutation, localized in the cytoplasmic tail, was associated with VF (P = 0.003), and the I4L mutation, in the fusion peptide, was associated with virological success (P = 0.004). CONCLUSIONS: In this study, new baseline substitutions in Gag, protease and g41, potentially impacting PI-based regimen outcome, were evidenced. Phenotypic analyses are required to confirm their role in the PI-resistance mechanism.