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Gonzalez CR, Basílio-Queirós D, Neehus AL, Merkert S, Tschritter D, Ünal S, H...
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Human CFTR deficient iPSC-macrophages reveal impaired functional and transcri...

FRONTIERS IN IMMUNOLOGY 2024 NOV 13; 15(?):? Article 1397886
Introduction Cystic fibrosis (CF) is a hereditary autosomal recessive disease driven by deleterious variants of the CFTR gene, leading, among other symptoms, to increased lung infection susceptibility. Mucus accumulation in the CF lung is, as of yet, considered as one important factor contributing to its colonization by opportunistic pathogens such as Pseudomonas aeruginosa. However, in recent years evidence was provided that alveolar macrophages, which form the first line of defense against airborne pathogens, seem to be intrinsically defective with regard to bactericidal functionality in the CF lung. To assess the impact of CFTR deficiency in human macrophages only insufficient systems are available.Methods To address this problem and to evaluate the role of CFTR in human macrophages, we successfully differentiated human induced pluripotent stem cells (iPSC) from a CF p.Phe508del homozygous individual and a healthy donor into primitive macrophages (iMac Delta F508 and iMacWT), respectively, and compared the bactericidal functionality in the relevant cell type.Results iMac Delta F508 showed impaired P. aeruginosa clearance and intracellular killing capacity in comparison to iMacWT. Furthermore, iMac Delta F508 exhibited a less acidic lysosomal pH, and upon P. aeruginosa infection, there were signs of mitochondrial fragmentation and autophagosome formation together with a hyperinflammatory phenotype and deficient type I interferon response.Conclusion In summary, we present a defective phenotype in iMac Delta F508 upon P. aeruginosa infection, which will constitute an ideal platform to further study the role of macrophages in the context of CF.
Sarfo FS, Frickmann H, Dompreh A, Osei Asibey S, Boateng R, Weinreich F, Osei...
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High Clinical Burden of Cryptosporidium spp. in Adult Patients with Ac...

MICROORGANISMS 2024 NOV; 12(11):? Article 2151
There is a paucity of information on the prevalence, risk factors, and clinical correlates of people living with HIV (PLWH) who are co-infected with Cryptosporidium spp. in the post-combined antiretroviral therapy era in Ghana. To provide such data, in this observational study, stool samples of 640 HIV-positive and 83 HIV-negative individuals in Ghana were screened for Cryptosporidium spp. Additionally, sociodemographic parameters, clinical symptoms, medication intake, and immunological parameters were assessed. The prevalence of Cryptosporidium spp. was 11.8% (n = 73) in HIV-positive and 1.2% (n = 1) in HIV-negative participants (p < 0.001). Within the group of HIV-positive participants, the prevalence reached 26.0% in patients with CD4+ T cell counts below 200 cells/mu L and 46.2% in the subgroup with CD4+ T cell counts below 50 cells/mu L. The frequencies of the clinical manifestation of weight loss and gastrointestinal symptoms were significantly higher in patients with Cryptosporidium spp. compared to those without co-infection (45.8% vs. 21.4%, p < 0.001 and 22.2% vs. 12.2%, p = 0.031, respectively). In the modern post-cART era, the acquisition of Cryptosporidium spp. among PLWH in Ghana is driven largely by the degree of immunosuppression. Access to cART and screening for Cryptosporidium spp. as part of routine care might help control and reduce the burden of the infection.
Hyun K, Ahn J, Kim H, Kim J, Kim YI, Park HS, Roeder RG, Lee JE, Kim J
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The BAF complex enhances transcription through interaction with H3K56ac in th...

NATURE COMMUNICATIONS 2024 NOV 7; 15(1):? Article 9614
Histone post-translational modifications play pivotal roles in eukaryotic gene expression. To date, most studies have focused on modifications in unstructured histone N-terminal tail domains and their binding proteins. However, transcriptional regulation by chromatin-effector proteins that directly recognize modifications in histone globular domains has yet to be clearly demonstrated, despite the richness of their multiple modifications. Here, we show that the ATP-dependent chromatin-remodeling BAF complex stimulates p53-dependent transcription through direct interaction with H3K56ac located on the lateral surface of the histone globular domain. Mechanistically, the BAF complex recognizes nucleosomal H3K56ac via the DPF domain in the DPF2 subunit and exhibits enhanced nucleosome-remodeling activity in the presence of H3K56ac. We further demonstrate that a defect in H3K56ac-BAF complex interaction leads to impaired p53-dependent gene expression and DNA damage responses. Our study provides direct evidence that histone globular domain modifications participate in the regulation of gene expression. The authors suggest that histone globular domain modifications participate in the regulation of gene expression. The ATP-dependent chromatin-remodeling BAF complex enhances transcription through direct interaction with H3K56ac located on the lateral surface of the histone globular domain.
Stoeckle MY, Ausubel JH, Hinks G, VanMorter SM
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A potential tool for marine biogeography: eDNA-dominant fish species differ a...

PLOS ONE 2024 NOV 11; 19(11):? Article e0313170
Effective ocean management asks for up-to-date knowledge of marine biogeography. Here we compare eDNA and gear-based assessments of marine fish populations using an approach that focuses on the commonest species. The protocol takes advantage of the "hollow curve" of species abundance distributions, with a minority of species comprising the great majority of individuals or biomass. We analyzed new and published teleost eDNA metabarcoding surveys from three neighboring northwest Atlantic coastal locations representing sandy, rocky, or estuary habitat. Fish eDNA followed a hollow curve species abundance distribution at each location-the 10 commonest taxa accounted for more than 90% of eDNA copies. Top ten taxa were designated eDNA-dominant species (eDDS) and categorized as habitat-associated (top 10 in one study) or as shared. eDDS by category were similarly abundant in concurrent bottom trawl and seine surveys. eDDS habitat category profiles correctly classified most (94%-100%) individual eDNA and capture measurements within surveys and recognized estuarine sites in other regional eDNA and seine studies. Using a category metric like that for habitats, eDDS demonstrated strong seasonal turnover concordant with trawl catch weights. eDNA seasonal profiles applied to historical trawl and seine records highlighted known long-term trends in mid-Atlantic fish populations. This study provides evidence that eDNA-abundant fish species differ among coastal habitats and by season consistent with gear-based assessments. Grouping abundant species by category facilitated comparisons among habitats and integration with established surveys. eDNA metabarcoding of dominant fish species potentially offers a useful tool for marine biogeography and ocean monitoring.
Coleman RT, Morantte I, Koreman GT, Cheng ML, Ding Y, Ruta V
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A modular circuit coordinates the diversification of courtship strategies

NATURE 2024 NOV 7; 635(8037):?
Mate recognition systems evolve rapidly to reinforce the reproductive boundaries between species, but the underlying neural mechanisms remain enigmatic. Here we leveraged the rapid coevolution of female pheromone production and male pheromone perception in Drosophila1,2 to gain insight into how the architecture of mate recognition circuits facilitates their diversification. While in some Drosophila species females produce unique pheromones that act to arouse their conspecific males, the pheromones of most species are sexually monomorphic such that females possess no distinguishing chemosensory signatures that males can use for mate recognition3. We show that Drosophila yakuba males evolved the ability to use a sexually monomorphic pheromone, 7-tricosene, as an excitatory cue to promote courtship. By comparing key nodes in the pheromone circuits across multiple Drosophila species, we reveal that this sensory innovation arises from coordinated peripheral and central circuit adaptations: a distinct subpopulation of sensory neurons has acquired sensitivity to 7-tricosene and, in turn, selectively signals to a distinct subset of P1 neurons in the central brain to trigger courtship. Such a modular circuit organization, in which different sensory inputs can independently couple to parallel courtship control nodes, may facilitate the evolution of mate recognition systems by allowing novel sensory modalities to become linked to male arousal. Together, our findings suggest how peripheral and central circuit adaptations can be flexibly coordinated to underlie the rapid evolution of mate recognition strategies across species. Peripheral and central circuit adaptations can be flexibly coordinated in Drosophila, and such a modular circuit organization may facilitate the evolution of mate recognition systems by allowing novel sensory modalities to become linked to male arousal.
De Faveri C, Mattheisen JM, Sakmar TP, Coin I
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Noncanonical Amino Acid Tools and Their Application to Membrane Protein Studi...

CHEMICAL REVIEWS 2024 NOV 7; 124(22):12498-12550
Methods rooted in chemical biology have contributed significantly to studies of integral membrane proteins. One recent key approach has been the application of genetic code expansion (GCE), which enables the site-specific incorporation of noncanonical amino acids (ncAAs) with defined chemical properties into proteins. Efficient GCE is challenging, especially for membrane proteins, which have specialized biogenesis and cell trafficking machinery and tend to be expressed at low levels in cell membranes. Many eukaryotic membrane proteins cannot be expressed functionally in E. coli and are most effectively studied in mammalian cell culture systems. Recent advances have facilitated broader applications of GCE for studies of membrane proteins. First, AARS/tRNA pairs have been engineered to function efficiently in mammalian cells. Second, bioorthogonal chemical reactions, including cell-friendly copper-free "click" chemistry, have enabled linkage of small-molecule probes such as fluorophores to membrane proteins in live cells. Finally, in concert with advances in GCE methodology, the variety of available ncAAs has increased dramatically, thus enabling the investigation of protein structure and dynamics by multidisciplinary biochemical and biophysical approaches. These developments are reviewed in the historical framework of the development of GCE technology with a focus on applications to studies of membrane proteins.
Sastre DE, Bournazos S, Du J, Boder EJ, Edgar JE, Azzam T, Sultana N, Hulicia...
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Potent efficacy of an IgG-specific endoglycosidase against IgG-mediated patho...

CELL 2024 NOV 27; 187(24):?
Endo-b-N-acetylglucosaminidases (ENGases) that specifically hydrolyze the Asn297-linked glycan on immunoglobulin G (IgG) antibodies, the major molecular determinant of fragment crystallizable (Fc) g receptor (FcgR) binding, are exceedingly rare. All previously characterized IgG-specific ENGases are multi-domain proteins secreted as an immune evasion strategy by Streptococcus pyogenes strains. Here, using in silico analysis and mass spectrometry techniques, we identified a family of single-domain ENGases secreted by pathogenic corynebacterial species that exhibit strict specificity for IgG antibodies. By X-ray crystallographic and surface plasmon resonance analyses, we found that the most catalytically efficient IgG-specific ENGase family member recognizes both protein and glycan components of IgG. Employing in vivo models, we demonstrated the remarkable efficacy of this IgG-specific ENGase in mitigating numerous pathologies that rely on FcgR-mediated effector functions, including T and B lymphocyte depletion, autoimmune hemolytic anemia, and antibody-dependent enhancement of dengue disease, revealing its potential for treating and/or preventing a wide range of IgG-mediated diseases in humans.
Zhang SY, Casanova JL
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Genetic defects of brain immunity in childhood herpes simplex encephalitis

NATURE 2024 NOV 21; 635(8039):563-573
Herpes simplex virus 1 (HSV-1) encephalitis (HSE) is the most common sporadic viral encephalitis in humans. It is life-threatening and has a first peak of incidence in childhood, during primary infection. Children with HSE are not particularly prone to other infections, including HSV-1 infections of tissues other than the brain. About 8-10% of childhood cases are due to monogenic inborn errors of 19 genes, two-thirds of which are recessive, and most of which display incomplete clinical penetrance. Childhood HSE can therefore be sporadic but genetic, enabling new diagnostic and therapeutic approaches. In this Review, we examine essential cellular and molecular mechanisms of cell-intrinsic antiviral immunity in the brain that are disrupted in individuals with HSE. These mechanisms include both known (such as mutations in the TLR3 pathway) and previously unknown (such as the TMEFF1 restriction factor) antiviral pathways, which may be dependent (for example, IFNAR1) or independent (for example, through RIPK3) of type I interferons. They operate in cortical or brainstem neurons, and underlie forebrain and brainstem infections, respectively. Conversely, the most severe inborn errors of leukocytes, including a complete lack of myeloid and/or lymphoid blood cells, do not underlie HSE. Thus congenital defects in intrinsic immunity in brain-resident neurons that underlie HSE broaden natural host defences against HSV-1 from the leukocytes of the immune system to other cells in the organism. This article reviews evidence that has emerged over the past two decades indicating that herpes simplex encephalitis in children can result from monogenic defects of brain immunity to herpes simplex virus 1.
Rosain J, Le Voyer T, Liu X, Gervais A, Polivka L, Cederholm A, Berteloot L, ...
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Incontinentia pigmenti underlies thymic dysplasia, autoantibodies to type I I...

JOURNAL OF EXPERIMENTAL MEDICINE 2024 NOV 4; 221(11):? Article e20231152
Human inborn errors of thymic T cell tolerance underlie the production of autoantibodies (auto-Abs) neutralizing type I IFNs, which predispose to severe viral diseases. We analyze 131 female patients with X-linked dominant incontinentia pigmenti (IP), heterozygous for loss-of-function (LOF) NEMO variants, from 99 kindreds in 10 countries. Forty-seven of these patients (36%) have auto-Abs neutralizing IFN-alpha and/or IFN-omega, a proportion 23 times higher than that for age-matched female controls. This proportion remains stable from the age of 6 years onward. On imaging, female patients with IP have a small, abnormally structured thymus. Auto-Abs against type I IFNs confer a predisposition to life-threatening viral diseases. By contrast, patients with IP lacking auto-Abs against type I IFNs are at no particular risk of viral disease. These results suggest that IP accelerates thymic involution, thereby underlying the production of auto-Abs neutralizing type I IFNs in at least a third of female patients with IP, predisposing them to life-threatening viral diseases.
Capili B, Anastasi JK
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An Introduction to Types of Quasi-Experimental Designs

AMERICAN JOURNAL OF NURSING 2024 NOV; 124(11):50-52