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Suryawanshi H, Max K, Bogardus KA, Sopeyin A, Chang MS, Morozov P, Castano PM, Tuschl T, Williams Z
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Dynamic genome-wide gene expression and immune cell composition in the developing human placenta

JOURNAL OF REPRODUCTIVE IMMUNOLOGY 2022 JUN; 151(?):? Article 103624
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.
Readnour BM, Ayinuola YA, Russo BT, Liang Z, Lee SW, Ploplis VA, Fischetti VA, Castellino FJ
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Evolution of Streptococcus pyogenes has maximized the efficiency of the Sortase A cleavage motif for cell wall transpeptidation

JOURNAL OF BIOLOGICAL CHEMISTRY 2022 JUN; 298(6):? Article 101940
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.
D'Angelo SP, Richards AL, Conley AP, Woo HJ, Dickson MA, Gounder M, Kelly C, Keohan ML, Movva S, Thornton K, Rosenbaum E, Chi P, Nacev B, Chan JE, Slotkin EK, Kiesler H, Adamson T, Ling LL, Rao P, Patel S, Livingston JA, Singer S, Agaram NP, Antonescu CR, Koff A, Erinjeri JP, Hwang SC, Qin LX, Donoghue MTA, Tap WD
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Pilot study of bempegaldesleukin in combination with nivolumab in patients with metastatic sarcoma

NATURE COMMUNICATIONS 2022 JUN 16; 13(1):? Article 3477
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.
Brodin P, Casari G, Townsend L, O'Farrelly C, Tancevski I, Loffler-Ragg J, Mogensen TH, Casanova JL
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Studying severe long COVID to understand post-infectious disorders beyond COVID-19

NATURE MEDICINE 2022 MAY; 28(5):879-882
Paccoud O, Vignier N, Boui M, Migaud M, Vironneau P, Kania R, Mechai F, Brun S, Alanio A, Tauziede-Espariat A, Adle-Biassette H, Ouedraogo E, Bustamante J, Bouchaud O, Casanova JL, Puel A, Lanternier F
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Invasive Rhinosinusitis Caused by Alternaria infectoria in a Patient with Autosomal Recessive CARD9 Deficiency and a Review of the Literature

JOURNAL OF FUNGI 2022 MAY; 8(5):? Article 446
Phaeohyphomycoses comprise a heterogeneous group of fungal infections caused by dematiaceous fungi and have primarily been reported in patients with underlying acquired immunodeficiencies, such as hematological malignancies or solid-organ transplants. Over the past decade, a growing number of patients with phaeohyphomycosis but otherwise healthy were reported with autosomal recessive (AR) CARD9 deficiency. We report a 28-year-old woman who presented with invasive rhinosinusitis caused by Alternaria infectoria. Following a candidate gene sequencing approach, we identified a biallelic loss-of-function mutation of CARD9, thereby further broadening the spectrum of invasive fungal diseases found in patients with inherited CARD9 deficiency. In addition, we reviewed 17 other cases of phaeohyphomycosis associated with AR CARD9 deficiency. Physicians should maintain a high degree of suspicion for inborn errors of immunity, namely CARD9 deficiency, when caring for previously healthy patients with phaeohyphomycosis, regardless of age at first presentation.
Chen ZL, Singh PK, Horn K, Strickland S, Norris EH
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Anti-HK antibody reveals critical roles of a 20-residue HK region for A?-induced plasma contact system activation

BLOOD ADVANCES 2022 MAY 24; 6(10):3090-3101
Alzheimer's disease (AD) is a neurodegenerative disorder and the leading cause of dementia. Vascular abnormalities and neuroinflammation play roles in AD pathogenesis. Plasma contact activation, which leads to fibrin clot formation and bradykinin release, is elevated in many AD patients, likely due to the ability of AD's pathogenic peptide beta-amyloid (A13) to induce its activation. Since overactivation of this system may be deleterious to AD patients, the development of inhibitors could be beneficial. Here, we show that 3E8, an antibody against a 20-amino acid region in domain 6 of high molecular weight kininogen (HK), inhibits A beta-induced intrinsic coagulation. Mechanistically, 3E8 inhibits contact system activation by blocking the binding of prekallikrein (PK) and factor XI (FXI) to HK, thereby preventing their activation and the continued activation of factor XII (FXII). The 3E8 antibody can also disassemble HK/PK and HK/FXI complexes in normal human plasma in the absence of a contact system activator due to its strong binding affinity for HK, indicating its prophylactic ability. Furthermore, the binding of A beta to both FXII and HK is critical for A beta-mediated contact system activation. These results suggest that a 20-amino acid region in domain 6 of HK plays a critical role in A beta-induced contact system activation, and this region may provide an effective strategy to inhibit or prevent contact system activation in related disorders.
Moy RH, Nguyen A, Loo JM, Yamaguchi N, Kajba CM, Santhanam B, Ostendorf BN, Wu YG, Tavazoie S, Tavazoie SF
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Functional genetic screen identifies ITPR3/calcium/RELB axis as a driver of colorectal cancer metastatic liver colonization

DEVELOPMENTAL CELL 2022 MAY 9; 57(9):1146-+
Metastatic colonization is the primary cause of death from colorectal cancer (CRC). We employed genomescale in vivo short hairpin RNA (shRNA) screening and validation to identify 26 promoters of CRC liver colonization. Among these genes, we identified a cluster that contains multiple targetable genes, including ITPR3, which promoted liver-metastatic colonization and elicited similar downstream gene expression programs. ITPR3 is a caffeine-sensitive inositol 1,4,5-triphosphate (IP3) receptor that releases calcium from the endoplasmic reticulum and enhanced metastatic colonization by inducing expression of RELB, a transcription factor that is associated with non-canonical NF-KB signaling. Genetic, cell biological, pharmacologic, and clinical association studies revealed that ITPR3 and RELB drive CRC colony formation by promoting cell survival upon substratum detachment or hypoxic exposure. RELB was sufficient to drive colonization downstream of ITPR3. Our findings implicate the ITPR3/calcium/RELB axis in CRC metastatic colony formation and uncover multiple clinico-pathologically associated targetable proteins as drivers of CRC metastatic colonization.
Leicher R, Osunsade A, Chua GNL, Faulkner SC, Latham AP, Watters JW, Nguyen T, Beckwitt EC, Christodoulou-Rubalcava S, Young PG, Zhang B, David Y, Liu SX
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Single-stranded nucleic acid binding and coacervation by linker histone H1

NATURE STRUCTURAL & MOLECULAR BIOLOGY 2022 MAY; 29(5):463-+
The H1 linker histone family is the most abundant group of eukaryotic chromatin-binding proteins. However, their contribution to chromosome structure and function remains incompletely understood. Here we use single-molecule fluorescence and force microscopy to directly visualize the behavior of H1 on various nucleic acid and nucleosome substrates. We observe that H1 coalesces around single-stranded DNA generated from tension-induced DNA duplex melting. Using a droplet fusion assay controlled by optical tweezers, we find that single-stranded nucleic acids mediate the formation of gel-like H1 droplets, whereas H1-double-stranded DNA and H1-nucleosome droplets are more liquid-like. Molecular dynamics simulations reveal that multivalent and transient engagement of H1 with unpaired DNA strands drives their enhanced phase separation. Using eGFP-tagged H1, we demonstrate that inducing single-stranded DNA accumulation in cells causes an increase in H1 puncta that are able to fuse. We further show that H1 and Replication Protein A occupy separate nuclear regions, but that H1 colocalizes with the replication factor Proliferating Cell Nuclear Antigen, particularly after DNA damage. Overall, our results provide a refined perspective on the diverse roles of H1 in genome organization and maintenance, and indicate its involvement at stalled replication forks. Using single-molecule imaging and manipulation, the authors show linker histone H1 preferentially forms phase-separated droplets with single-stranded nucleic acids over double-stranded DNA and nucleosomes, suggesting a noncanonical nuclear function.
Wisanpitayakorn P, Mickolajczyk KJ, Hancock WO, Vidali L, Tuzel E
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Measurement of the persistence length of cytoskeletal filaments using curvature distributions

BIOPHYSICAL JOURNAL 2022 MAY 17; 121(10):1813-1822
Cytoskeletal filaments, such as microtubules and actin filaments, play important roles in the mechanical integrity of cells and the ability of cells to respond to their environment. Measuring the mechanical properties of cytoskeletal structures is crucial for gaining insight into intracellular mechanical stresses and their role in regulating cellular processes. One of the ways to characterize these mechanical properties is by measuring their persistence length, the average length over which filaments stay straight. There are several approaches in the literature for measuring filament deformations, such as Fourier analysis of images obtained using fluorescence microscopy. Here, we show how curvature distributions can be used as an alternative tool to quantify biofilament deformations, and investigate how the apparent stiffness of filaments depends on the resolution and noise of the imaging system. We present analytical calculations of the scaling curvature distributions as a function of filament discretization, and test our predictions by comparing Monte Carlo simulations with results from existing techniques. We also apply our approach to microtubules and actin filaments obtained from in vitro gliding assay experiments with high densities of nonfunctional motors, and calculate the persistence length of these filaments. The presented curvature analysis is significantly more accurate compared with existing approaches for small data sets, and can be readily applied to both in vitro and in vivo filament data through the use of the open-source codes we provide.
Troya J, Bastard P, Casanova JL, Abel L, Pujol A
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Low Lymphocytes and IFN-Neutralizing Autoantibodies as Biomarkers of COVID-19 Mortality

JOURNAL OF CLINICAL IMMUNOLOGY 2022 MAY; 42(4):738-741