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Picornaviruses are small RNA viruses that hijack host cell machinery to promote their replication. During infection, these viruses express two proteases, 2Apro and 3Cpro, which process viral proteins. They also subvert a number of host functions, including innate immune responses, host protein synthesis, and intracellular transport, by utilizing poorly understood mechanisms for rapidly and specifically targeting critical host proteins. Here, we used proteomic tools to characterize 2Apro interacting partners, functions, and targeting mechanisms. Our data indicate that, initially, 2Apro primarily targets just two cellular proteins: eukaryotic translation initiation factor eIF4G (a critical component of the protein synthesis machinery) and Nup98 (an essential component of the nuclear pore complex, responsible for nucleocytoplasmic transport). The protease appears to employ two different cleavage mechanisms; it likely interacts with eIF3L, utilizing the eIF3 complex to proteolytically access the eIF4G protein but also directly binds and degrades Nup98. This Nup98 cleavage results in only a marginal effect on nuclear import of proteins, while nuclear export of proteins and mRNAs were more strongly affected. Collectively, our data indicate that 2Apro selectively inhibits protein translation, key nuclear export pathways, and cellular mRNA localization early in infection to benefit viral replication at the expense of particular cell functions.

In an international cohort of 112 children hospitalized for moderate to critical COVID-19 pneumonia, we identified 12 children with one of four known recessive inborn errors of type I interferon immunity: X-linked TLR7 and autosomal IFNAR1, STAT2, and TYK2 deficiencies. Recessive or dominant inborn errors of type I interferon (IFN) immunity can underlie critical COVID-19 pneumonia in unvaccinated adults. The risk of COVID-19 pneumonia in unvaccinated children, which is much lower than in unvaccinated adults, remains unexplained. In an international cohort of 112 children (<16 yr old) hospitalized for COVID-19 pneumonia, we report 12 children (10.7%) aged 1.5-13 yr with critical (7 children), severe (3), and moderate (2) pneumonia and 4 of the 15 known clinically recessive and biochemically complete inborn errors of type I IFN immunity: X-linked recessive TLR7 deficiency (7 children) and autosomal recessive IFNAR1 (1), STAT2 (1), or TYK2 (3) deficiencies. Fibroblasts deficient for IFNAR1, STAT2, or TYK2 are highly vulnerable to SARS-CoV-2. These 15 deficiencies were not found in 1,224 children and adults with benign SARS-CoV-2 infection without pneumonia (P = 1.2 x 10(-11)) and with overlapping age, sex, consanguinity, and ethnicity characteristics. Recessive complete deficiencies of type I IFN immunity may underlie similar to 10% of hospitalizations for COVID-19 pneumonia in children.

Backgrounds: While many studies agree that consanguinity increases the rate of congenital heart disease (CHD), few genome analyses have been conducted with consanguineous CHD cohorts. Methods: We recruited 73 CHD probands from consanguineous families in Turkey and used whole-exome sequencing (WES) to identify genetic lesions in these patients. Results: On average, each patient had 6.95 rare damaging homozygous variants, 0.68 of which are loss-of-function (LoF) variants. Seven patients (9.6%) carried damaging homozygous variants in five causal CHD genes. Six of those patients exhibited laterality defects (six HTX and one D-TGA). Three additional patients (4.1%) harbored other types of CHD-associated genomic alterations, which overall explained 13.7% (10/73) of the cohort. The contribution from recessive variants in our cohort is higher than 1.8% reported from a cohort of 2871 CHD subjects where 5.6% of subjects met the criteria for consanguinity. Conclusions: Our WES screen of a Turkish consanguineous population with structural CHD revealed its unique genetic architecture. Six of seven damaging homozygous variants in CHD causal genes occur in the setting of laterality defects implies a strong contribution from consanguinity to these defects specifically. Our study thus provided valuable information about the genetic landscape of CHD in consanguineous families in Turkey.

Despite the central role of the placenta in supporting a pregnancy, relatively little is known about transcriptomic and immune-cell changes that occur across gestation. To generate a reference gene expression map of first (T1), second (T2) and third (T3) trimester human placenta, and assess differences in transcriptome in maternal versus fetal side tissues sections of full-term placenta, we performed RNA-Seq analysis on 64 biopsy samples from 18 placentas across all three gestations. We identified 1120 differentially expressed genes in placenta tissues from T1 and T3 samples using a generalized linear model within DESeq2. In total, 411 and 709 genes were positively associated with T1 and T3 placenta, respectively. Comparison of the top 200 differentially expressed genes in the T1 placenta with T3 showed that most of the top enriched biological processes were related to cell division and proliferation. T1 and T2 tissues shared expression of fibroblast-specific COL6A2, HGF, and SPP1 genes. In T3 samples, the expression of genes relating to vasculature development and regulation were highly enriched. Monocytes and NK cell population increased in T3 compared to T1 and T2, whereas Hofbauer cell proportion expanded significantly in T2 and then decreased in T3 samples. There were no significant gene expression dif-ferences in the maternal vs. fetal side in T3 placentas. Gene expression patterns shift temporally across trimesters but not spatially across the placenta, at least at the resolution of the biopsy samples. The genes and gene set we identified here represent a valuable resource for studying pathology in pregnancy-related disorders.

Trafficking of M-protein (Mprt) from the cytosol of Group A Streptococcus pyogenes (GAS) occurs via Sec translocase membrane channels that associate with Sortase A (SrtA), an enzyme that catalyzes cleavage of Mprt at the proximal C-terminal [-LPST(355*)GEAA-] motif and subsequent transpeptidation of the Mprt-containing product to the cell wall (CW). These steps facilitate stable exposure of the N-terminus of Mprt to the extracellular milieu where it interacts with ligands. Previously, we found that inactivation of SrtA in GAS cells eliminated Mprt CW transpeptidation but effected little reduction in its cell surface exposure, indicating that the C-terminus of Mprt retained in the cytoplasmic membrane (CM) extends its N-terminus to the cell surface. Herein, we assessed the effects of mutating the Thr(355) residue in the WT SrtA consensus sequence (LPST(355*)GEAA-) in a specific Mprt, PAM. In vitro, we found that synthetic peptides with mutations (LPSX(355)GEAA) in the SrtA cleavage site displayed slower cleavage activities with rSrtA than the WT peptide. Aromatic residues at X had the lowest activities. Nonetheless, PAM/[Y(355)G] still transpeptidated the CW in vivo. However, when using isolated CMs from srtA-inactivated GAS cells, rapid cleavage of PAM/[LPSY(355)GEAA] occurred at E-357* but transpeptidation did not take place. These results show that another CM-resident enzyme nonproductively cleaved PAM/[LPSYGE(357*)AA]. However, SrtA associated with the translocon channel in vivo cleaved and transpeptidated PAM/ [LPSX(355*)GEAA] variants. These CM features allow diverse cleavage site variants to covalently attach to the CW despite the presence of other potent nonproductive CM proteases.

PD-1 blockade (nivolumab) efficacy remains modest for metastatic sarcoma. In this paper, we present an open-label, non-randomized, non-comparative pilot study of bempegaldesleukin, a CD122-preferential interleukin-2 pathway agonist, with nivolumab in refractory sarcoma at Memorial Sloan Kettering/MD Anderson Cancer Centers (NCT03282344). We report on the primary outcome of objective response rate (ORR) and secondary endpoints of toxicity, clinical benefit, progression-free survival, overall survival, and durations of response/treatment. In 84 patients in 9 histotype cohorts, all patients experienced >= 1 adverse event and treatment-related adverse event; 1 death was possibly treatment-related. ORR was highest in angiosarcoma (3/8) and undifferentiated pleomorphic sarcoma (2/10), meeting predefined endpoints. Results of our exploratory investigation of predictive biomarkers show: CD8 + T cell infiltrates and PD-1 expression correlate with improved ORR; upregulation of immune-related pathways correlate with improved efficacy; Hedgehog pathway expression correlate with resistance. Exploration of this combination in selected sarcomas, and of Hedgehog signaling as a predictive biomarker, warrants further study in larger cohorts. The activity of PD-1 blockade in patients with sarcoma has been modest so far. Here, the authors report the results of a pilot clinical trial to assess the efficacy and safety of bempegaldesleukin, a CD122-preferential interleukin-2 (IL-2) pathway agonist, in combination with the PD1 blockade (nivolumab) in patients with locally advanced or metastatic high-grade sarcoma.

Microbiome data have several specific characteristics (sparsity and compositionality) that introduce challenges in data analysis. The integration of prior information regarding the data structure, such as phylogenetic structure and repeated-measure study designs, into analysis, is an effective approach for revealing robust patterns in microbiome data. Past methods have addressed some but not all of these challenges and features: for example, robust principal-component analysis (RPCA) addresses sparsity and compositionality; compositional tensor factorization (CIF) addresses sparsity, compositionality, and repeated measure study designs; and UniFrac incorporates phylogenetic information. Here we introduce a strategy of incorporating phylogenetic information into RPCA and CTF. The resulting methods, phylo-RPCA, and phylo-CTF, provide substantial improvements over state-of-the-art methods in terms of discriminatory power of underlying clustering ranging from the mode of delivery to adult human lifestyle. We demonstrate quantitatively that the addition of phylogenetic information improves effect size and classification accuracy in both data-driven simulated data and real microbiome data. IMPORTANCE Microbiome data analysis can be difficult because of particular data features, some unavoidable and some due to technical limitations of DNA sequencing instruments. The first step in many analyses that ultimately reveals patterns of similarities and differences among sets of samples (e.g., separating samples from sick and healthy people or samples from seawater versus soil) is calculating the difference between each pair of samples. We introduce two new methods to calculate these differences that combine features of past methods, specifically being able to take into account the principles that most types of microbes are not in most samples (sparsity), that abundances are relative rather than absolute (compositionality), and that all microbes have a shared evolutionary history (phylogeny). We show using simulated and real data that our new methods provide improved classification accuracy of ordinal sample clusters and increased effect size between sample groups on beta-diversity distances.

Antiretroviral therapy is highly effective in suppressing human immunodeficiency virus (HIV)(1). However, eradication of the virus in individuals with HIV has not been possible to date(2). Given that HIV suppression requires life-long antiretroviral therapy, predominantly on a daily basis, there is a need to develop clinically effective alternatives that use long-acting antiviral agents to inhibit viral replication(3). Here we report the results of a two-component clinical trial involving the passive transfer of two HIV-specific broadly neutralizing monoclonal antibodies, 3BNC117 and 10-1074. The first component was a randomized, double-blind, placebo-controlled trial that enrolled participants who initiated antiretroviral therapy during the acute/early phase of HIV infection. The second component was an open-label single-arm trial that enrolled individuals with viraemic control who were naive to antiretroviral therapy. Up to 8 infusions of 3BNC117 and 10-1074, administered over a period of 24 weeks, were well tolerated without any serious adverse events related to the infusions. Compared with the placebo, the combination broadly neutralizing monoclonal antibodies maintained complete suppression of plasma viraemia (for up to 43 weeks) after analytical treatment interruption, provided that no antibody-resistant HIV was detected at the baseline in the study participants. Similarly, potent HIV suppression was seen in the antiretroviral-therapy-naive study participants with viraemia carrying sensitive virus at the baseline. Our data demonstrate that combination therapy with broadly neutralizing monoclonal antibodies can provide long-term virological suppression without antiretroviral therapy in individuals with HIV, and our experience offers guidance for future clinical trials involving next-generation antibodies with long half-lives.

Subacute sclerosing panencephalitis, a late complication of measles, is still present during epidemics of this disease due to insufficient vaccination. After a historical review, the importance of the diagnostic criteria and the pathophysiology of SSEP are discussed. Numerous studies on the parameters of innate immunity and interferon responses tend to show a decrease in the activity of cellular immunity. Several hypotheses are formulated based on the publications of the different forms of the disease: Congenital, perinatal, forms with short incubation similar to acute inclusion encephalitis (AIE), rapidly evolving forms, forms of the immunocompromised, or even adults. Familial forms have been identified, suggesting a genetic cause. Based on the duration of the latency period, two groups have been individualized, prompting a retrospective and prospective analysis of the exomes of these patients. The knowledge of the genes involved should be useful for the understanding of the pathophysiology of SSPE and other late neurological RNA virus infections.

Background: Psoriasis, a chronic inflammatory disease dependent on the IL-23/T(H)17 pathway, is initiated through plasmacytoid dendritic cell activation and type I IFN induction in the skin. Deucravacitinib, a selective tyrosine kinase 2 (TYK2) inhibitor, blocks IL-23, IL-12, and type I IFN signaling in cellular assays. Objective: We investigated changes in IL-23/T(H)17 and type I IFN pathway biomarkers and gene responses as well as measures of selectivity for TYK2 over Janus kinases (JAKs) 1-3 in patients with moderate to severe psoriasis receiving deucravacitinib. Methods: Deucravacitinib was evaluated in a randomized, placebo-controlled, dose-ranging trial. Biopsy samples from nonlesional (day 1) and lesional skin (days 1, 15, and 85) were assessed for changes in IL-23/IL-12 and type I IFN pathway biomarkers by quantitative reverse-transcription polymerase chain reaction, RNA sequencing, and immunohistochemistry. Laboratory markers were measured in blood. Percentage change from baseline in Psoriasis Area and Severity Index (PASI) score was assessed. Results: IL-23 pathway biomarkers in lesional skin returned toward nonlesional levels dose-dependently with deucravacitinib. IFN and IL-12 pathway genes were normalized. Markers of keratinocyte dysregulation, keratin-16, and beta-defensin genes approached nonlesional levels with effective doses. Select laboratory parameters affected by JAK1-3 inhibition were not affected by deucravacitinib. Greater improvements in PASI scores, correlated with biomarker changes, were seen with the highest doses of deucravacitinib versus lower doses or placebo. Conclusion: Robust clinical efficacy with deucravacitinib treatment was associated with decreases in IL-23/TH17 and IFN pathway biomarkers. The lack of effect seen on biomarkers specific to JAK1-3 inhibition supports selectivity of deucravacitinib for TYK2; larger confirmatory studies are needed.