Skip to main content

Publications search

Found 37443 matches. Displaying 891-900
Hon-Balla B, Erdos M
Show All Authors

Chronic mucocutaneous candidiasis (opens in new window)

ORVOSI HETILAP 2022 JAN; 163(5):171-180
Show Abstract
Chronic mucocutaneous candidiasis is a genetically heterogeneous group of disorders, which are characterised by chronic or recurrent non-invasive skin, nail and mucous membrane infections caused by Candida. The increased susceptibility to Candida infections is due to a Th17-cell mediated immune detect with different gene mutations in the background. The isolated form of the disorder, referred to as chronic mucocutaneous candidiasis, presents primarily or only with mucocutaneous candidiasis. In contrast, the syndromic form of the disorder is characterised, besides the non-invasive Candida infections, by autoimmune disorders, which most commonly affect the endocrine system. Genetic tests are important in confirming the diagnosis, which in affected families would provide the opportunity for prenatal genetic testing. The authors present the main types of chronic mucocutaneous candidiasis, exploring the clinical aspects, diagnostic methods, and available therapies. Furthermore, the authors conclude the molecular genetic background and the currently known pathomechanism of the disorder.
Yao NY, Zhang D, Yurieva O, O'Donnell ME
Show All Authors

CMG helicase can use ATP gamma S to unwind DNA Implications for the rate-limiting step in the reaction mechanism (opens in new window)

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2022 JAN 25; 119(4):? Article e2119580119
Show Abstract
The adenosine triphosphate (ATP) analog ATP gamma S often greatly slows or prevents enzymatic ATP hydrolysis. The eukaryotic CMG (Cdc45, Mcm2 to 7, GINS) replicative helicase is presumed unable to hydrolyze ATP gamma S and thus unable to perform DNA unwinding, as documented for certain other helicases. Consequently, ATP gamma S is often used to "preload" CMG onto forked DNA substrates without unwinding before adding ATP to initiate helicase activity. We find here that CMG does hydrolyze ATP gamma S and couples it to DNA unwinding. Indeed, the rate of unwinding of a 20- and 30-mer duplex fork of different sequences by CMG is only reduced 1- to 1.5-fold using ATP gamma S compared with ATP. These findings imply that a conformational change is the rate-limiting step during CMG unwinding, not hydrolysis. Instead of using ATP gamma S for loading CMG onto DNA, we demonstrate here that nonhydrolyzable adenylyl-imidodiphosphate (AMP-PNP) can be used to preload CMG onto a forked DNA substrate without unwinding.
Naik HB, Alhusayen R, Frew J, Guilbault S, Hills NK, Ingram JR, Kudlinski MV, Lowes MA, Marzano AV, Paul M, Villumsen B, Yannuzzi CA
Show All Authors

Biologic therapy is not associated with increased COVID-19 severity in patients with hidradenitis suppurativa: Initial findings from the Global Hidradenitis Suppurativa COVID-19 Registry (opens in new window)

JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY 2022 JAN; 86(1):249-252
Show Abstract
Victora GD, Nussenzweig MC
Show All Authors

Germinal Centers (opens in new window)

ANNUAL REVIEW OF IMMUNOLOGY 2022; 40(?):413-442
Show Abstract
Germinal centers (GCs) are microanatomical sites of B cell clonal expansion and antibody affinity maturation. Therein, B cells undergo the Darwinian process of somatic diversification and affinity-driven selection of immunoglobulins that produces the high-affinity antibodies essential for effective humoral immunity. Here, we review recent developments in the field of GC biology, primarily as it pertains to GCs induced by infection or immunization. First, we summarize the phenotype and function of the different cell types that compose the GC, focusing on GC B cells. Then, we review the cellular and molecular bases of affinity-dependent selection within the GC and the export of memory and plasma cells. Finally, we present an overview of the emerging field of GC clonal dynamics, focusing on how GC and post-GC selection shapes the diversity of antibodies secreted into serum.
Carapito R, Li R, Helms J, Carapito C, Gujja S, Rolli V, Guimaraes R, Malagon-Lopez J, Spinnhirny P, Lederle A, Mohseninia R, Hirschler A, Muller L, Bastard P, Gervais A, Zhang Q, Danion F, Ruch Y, Schenck M, Collange O, Chamaraux-Tran TN, Molitor A, Pichot A, Bernard A, Tahar O, Bibi-Triki S, Wu HG, Paul N, Mayeur S, Larnicol A, Laumond G, Frappier J, Schmidt S, Hanauer A, Macquin C, Stemmelen T, Simons M, Mariette X, Hermine O, Fafi-Kremer S, Goichot B, Drenou B, Kuteifan K, Pottecher J, Mertes PM, Kailasan S, Aman MJ, Pin E, Nilsson P, Thomas A, Viari A, Sanlaville D, Schneider F, Sibilia J, Tharaux PL, Casanova JL, Hansmann Y, Lidar D, Radosavljevic M, Gulcher JR, Meziani F, Moog C, Chittenden TW, Bahram S
Show All Authors

Identification of driver genes for critical forms of COVID-19 in a deeply phenotyped young patient cohort (opens in new window)

SCIENCE TRANSLATIONAL MEDICINE 2022 JAN 19; 14(628):? Article eabj7521
Show Abstract
The drivers of critical coronavirus disease 2019 (COVID-19) remain unknown. Given major confounding factors such as age and comorbidities, true mediators of this condition have remained elusive. We used a multi-omics analysis combined with artificial intelligence in a young patient cohort where major comorbidities were excluded at the onset. The cohort included 47 "critical" (in the intensive care unit under mechanical ventilation) and 25 "non-critical" (in a non-critical care ward) patients with COVID-19 and 22 healthy individuals. The analyses included whole-genome sequencing, whole-blood RNA sequencing, plasma and blood mononuclear cell proteomics, cytokine profiling, and high-throughput immunophenotyping. An ensemble of machine learning, deep learning, quantum annealing, and structural causal modeling were used. Patients with critical COVID-19 were characterized by exacerbated inflammation, perturbed lymphoid and myeloid compartments, increased coagulation, and viral cell biology. Among differentially expressed genes, we observed up-regulation of the metalloprotease ADAM9. This gene signature was validated in a second independent cohort of 81 critical and 73 recovered patients with COVID-19 and was further confirmed at the transcriptional and protein level and by proteolytic activity. Ex vivo ADAM9 inhibition decreased severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uptake and replication in human lung epithelial cells. In conclusion, within a young, otherwise healthy, cohort of individuals with COVID-19, we provide the landscape of biological perturbations in vivo where a unique gene signature differentiated critical from non-critical patients. We further identified ADAM9 as a driver of disease severity and a candidate therapeutic target.
Carlson AL, Floyd RJ, Arbona RJR, Henderson KS, Perkins C, Lipman NS
Show All Authors

Assessing Elimination of Mouse Kidney Parvovirus from Cages by Mechanical Washing (opens in new window)

JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE 2022 JAN; 61(1):61-66
Show Abstract
Mouse kidney parvovirus (MKPV), a newly identified parvovirus of the genus Chaphamaparvovirus, causes inclusion body nephropathy in severely immunocompromised mice and is prevalent in research mouse colonies. As nonenveloped viruses, mammalian parvoviruses are stable and generally resist thermal inactivation; however, as a novel and highly divergent parvovirus, the thermal stability of MKPV is undefined. This study aimed to evaluate the ability of cage sanitization in a mechanical washer to eliminate MKPV. Cages contaminated by MKPV-infected mice were assigned to 1 of 3 treatment groups: 1) control (bedding change only); 2) sanitization in a tunnel washer (88 degrees C final rinse for 20 s); or 3) sanitization in a tunnel washer followed by autoclave sterilization (121 degrees C for 20 min). The presence of MKPV on the cage's interior surface was assessed by PCR of cage swab extracts collected before and after cage treatment. After treatment and swabbing, each cage housed 4 MKPV-negative CD1 mice. Each group of naive CD1 mice was assigned to one of the treatment groups and was housed in a cage from this group for two, 1 wk periods. At 12, 17, and 20 wk after the first exposure, renal tissue was collected from 1 test mouse per cage and assessed for MKPV by PCR. MKPV was detected by PCR on the surface of 63% of the pretreatment cages. All cages sanitized in a tunnel washer with or without sterilization were PCR negative after treatment. Seven of 10 mice housed in untreated cages contained a mouse positive for MKPV by 20 wk after exposure. None of the mice housed in cages sanitized in a tunnel washer with or without sterilization tested positive for MKPV at any time point. This study indicates that MKPV contaminated caging can result in MKPV infection of mice, and the use of a tunnel washer at the temperature and duration evaluated was sufficient to remove MKPV nucleic acid and prevent MKPV transmission.
Cho A, Gaebler C, Olveira T, Ramos V, Saad M, Lorenzi JCC, Gazumyan A, Moir S, Caskey M, Chun TW, Nussenzweig MC
Show All Authors

Longitudinal clonal dynamics of HIV-1 latent reservoirs measured by combination quadruplex polymerase chain reaction and sequencing (opens in new window)

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2022 JAN 25; 119(4):? Article e2117630119
Show Abstract
HIV-1 infection produces a long-lived reservoir of latently infected CD4(+) T cells that represents the major barrier to HIV-1 cure. The reservoir contains both intact and defective proviruses, but only the proviruses that are intact can reinitiate infection upon cessation of antiretroviral therapy (ART). Here we combine four-color quantitative PCR and next-generation sequencing (Q4PCR) to distinguish intact and defective proviruses and measure reservoir content longitudinally in 12 infected individuals. Q4PCR differs from other PCR-based methods in that the amplified proviruses are sequence verified as intact or defective. Samples were collected systematically over the course of up to 10 y beginning shortly after the initiation of ART. The size of the defective reservoir was relatively stable with minimal decay during the 10-y observation period. In contrast, the intact proviral reservoir decayed with an estimated half-life of 4.9 y. Nevertheless, both intact and defective proviral reservoirs are dynamic. As a result, the fraction of intact proviruses found in expanded clones of CD4(+) T cells increases over time with a concomitant decrease in overall reservoir complexity. Thus, reservoir decay measurements by Q4PCR are quantitatively similar to viral outgrowth assay (VOA) and intact proviral DNA PCR assay (IPDA) with the addition of sequence information that distinguishes intact and defective proviruses and informs reservoir dynamics. The data are consistent with the notion that intact and defective proviruses are under distinct selective pressure, and that the intact proviral reservoir is progressively enriched in expanded clones of CD4(+) T cells resulting in diminishing complexity over time.
Cridland JM, Majane AC, Zhao L, Begun DJ
Show All Authors

Population biology of accessory gland-expressed de novo genes in Drosophila melanogaster (opens in new window)

GENETICS 2022 JAN; 220(1):? Article iyab207
Show Abstract
Early work on de novo gene discovery in Drosophila was consistent with the idea that many such genes have male-biased patterns of expression, including a large number expressed in the testis. However, there has been little formal analysis of variation in the abundance and properties of de novo genes expressed in different tissues. Here, we investigate the population biology of recently evolved de novo genes expressed in the Drosophila melanogaster accessory gland, a somatic male tissue that plays an important role in male and female fertility and the post mating response of females, using the same collection of inbred lines used previously to identify testis-expressed de novo genes, thus allowing for direct cross tissue comparisons of these genes in two tissues of male reproduction. Using RNA-seq data, we identify candidate de novo genes located in annotated intergenic and intronic sequence and determine the properties of these genes including chromosomal location, expression, abundance, and coding capacity. Generally, we find major differences between the tissues in terms of gene abundance and expression, though other properties such as transcript length and chromosomal distribution are more similar. We also explore differences between regulatory mechanisms of de novo genes in the two tissues and how such differences may interact with selection to produce differences in D. melanogaster de novo genes expressed in the two tissues.
Barrangou R, Marraffini LA
Show All Authors

Turning CRISPR on with antibiotics (opens in new window)

CELL HOST & MICROBE 2022 JAN 12; 30(1):12-14
Show Abstract
CRISPR-Cas systems have the ability to integrate invasive DNA sequences to build adaptive immunity in bacteria. In this issue Dimitriu et al. show bacteriostatic antibiotics prompt CRISPR acquisition events, illustrating how environmental conditions affect complex dynamics between host and virus and the corresponding biological and genetic arms race.
Gross A, Zhou BH, Bewersdorf L, Schwarz N, Schacht GM, Boor P, Hoeft K, Hoffmann B, Fuchs E, Kramann R, Merkel R, Leube RE, Strnad P
Show All Authors

Desmoplakin Maintains Transcellular Keratin Scaffolding and Protects From Intestinal Injury (opens in new window)

CELLULAR AND MOLECULAR GASTROENTEROLOGY AND HEPATOLOGY 2022; 13(4):1181-1200
Show Abstract
BACKGROUND & AIMS: Desmosomes are intercellular junctions connecting keratin intermediate filaments of neighboring cells. The cadherins desmoglein 2 (Dsg2) and desmocollin 2 mediate cell-cell adhesion, whereas desmoplakin (Dsp) provides the attachment of desmosomes to keratins. Although the importance of the desmosome-keratin network is well established in mechanically challenged tissues, we aimed to assess the currently understudied function of desmosomal proteins in intestinal epithelia.& nbsp;METHODS: We analyzed the intestine-specific villin-Cre DSP (DSP delta IEC) and the combined intestine-specific DSG2/DSP delta IEC (delta Dsg2/Dsp) knockout mice. Cross-breeding with keratin 8-yellow fluorescent protein knock-in mice and generation of organoids was performed to visualize the keratin network. A Dsp-deficient colorectal carcinoma HT29-derived cell line was generated and the role of Dsp in adhesion and mechanical stress was studied in dispase assays, after exposure to uniaxial cell stretching and during scratch assay.& nbsp;RESULTS: The intestine of DSP delta IEC mice was histopathologically inconspicuous. Intestinal epithelial cells, however, showed an accelerated migration along the crypt and an enhanced shedding into the lumen. Increased intestinal permeability and altered levels of desmosomal proteins were detected. An inconspicuous phenotype also was seen in delta Dsg2/Dsp mice. After dextran sodium sulfate treatment, DSP delta IEC mice developed more pronounced colitis. A retracted keratin network was seen in the intestinal epithelium of DSP delta IEC/keratin 8-yellow fluorescent protein mice and organoids derived from these mice presented a collapsed keratin network. The level, phosphorylation status, and solubility of keratins were not affected. Dsp-deficient HT29 cells had an impaired cell adhesion and suffered from increased cellular damage after stretch.& nbsp;CONCLUSIONS: Our results show that Dsp is required for proper keratin network architecture in intestinal epithelia, mechanical resilience, and adhesion, thereby protecting from injury.