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1.
Arch Orthop Trauma Surg ; 144(5): 1969-1976, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554204

RESUMO

PURPOSE: This study presents an abnormality of the musculus rectus capitis posterior minor (RCPmi) as a new etiological factor for nontraumatic sagittal plane instability in the C0-C1-C2-complex, with a focus on identifying the absence or atrophy of RCPmi on both sides. METHODS: A 36-year-old male patient presented with recurring neck pain (VAS 8/10) and tingling paresthesia in the entire left hand over a six-month period, without significant neurological deficits. Radiated arm pain was not reported. Imaging examinations revealed sagittal plane instability in the C0-C1-C2-complex, spinal canal stenosis (SCS), and myelopathy at the C1 level. Subsequently, a dorsal C0-1 reposition and fusion with laminectomy were performed. RESULTS: The congenital absence or atrophy of RCPmi, leading to the lack of cephalad-rearward traction on the C1-tuberculum-posterius, induced a developmental failure of the C1 posterior arch. Consequently, the oblate-shaped C1 posterior arch lost support from the underlying C2 posterior arch and the necessary cephalad-rearward traction throughout the patient's 36-year life. This gradual loss of support and traction caused the C1 posterior arch to shift gradually to the anterior side of the C2 posterior arch, resulting in a rotational subluxation centered on the C0/1 joints in the sagittal plane. Ultimately, this led to SCS and myelopathy. Traumatic factors were ruled out from birth to the present, and typical degenerative changes were not found in the upper cervical spine, neck muscles, and ligaments. CONCLUSION: In this case, we not only report the atrophy or absence of RCPmi as a new etiological factor for nontraumatic sagittal plane instability in the C0-C1-C2-complex but also discovered a new function of RCPmi. The cephalad-rearward traction exerted by RCPmi on the C1 posterior arch is essential for the development of a normal C1 anterior-posterior diameter.


Assuntos
Vértebras Cervicais , Instabilidade Articular , Humanos , Masculino , Adulto , Instabilidade Articular/cirurgia , Instabilidade Articular/etiologia , Instabilidade Articular/diagnóstico por imagem , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Articulação Atlantoaxial/diagnóstico por imagem , Articulação Atlantoaxial/cirurgia , Fusão Vertebral/métodos
2.
Sci Immunol ; 9(93): eadd4818, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38427718

RESUMO

T follicular helper (TFH) cells are essential for effective antibody responses, but deciphering the intrinsic wiring of mouse TFH cells has long been hampered by the lack of a reliable protocol for their generation in vitro. We report that transforming growth factor-ß (TGF-ß) induces robust expression of TFH hallmark molecules CXCR5 and Bcl6 in activated mouse CD4+ T cells in vitro. TGF-ß-induced mouse CXCR5+ TFH cells are phenotypically, transcriptionally, and functionally similar to in vivo-generated TFH cells and provide critical help to B cells. The study further reveals that TGF-ß-induced CXCR5 expression is independent of Bcl6 but requires the transcription factor c-Maf. Classical TGF-ß-containing T helper 17 (TH17)-inducing conditions also yield separate CXCR5+ and IL-17A-producing cells, highlighting shared and distinct cell fate trajectories of TFH and TH17 cells. We demonstrate that excess IL-2 in high-density T cell cultures interferes with the TGF-ß-induced TFH cell program, that TFH and TH17 cells share a common developmental stage, and that c-Maf acts as a switch factor for TFH versus TH17 cell fates in TGF-ß-rich environments in vitro and in vivo.


Assuntos
Linfócitos T Auxiliares-Indutores , Fator de Crescimento Transformador beta , Animais , Camundongos , Fator de Crescimento Transformador beta/metabolismo , Linfócitos B , Linfócitos T CD4-Positivos , Diferenciação Celular , Proteínas Proto-Oncogênicas c-maf/metabolismo
3.
Hemasphere ; 7(10): e958, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37841755

RESUMO

Activating colony-stimulating factor-3 receptor gene (CSF3R) mutations are recurrent in acute myeloid leukemia (AML) with t(8;21) translocation. However, the nature of oncogenic collaboration between alterations of CSF3R and the t(8;21) associated RUNX1-RUNX1T1 fusion remains unclear. In CD34+ hematopoietic stem and progenitor cells from healthy donors, double oncogene expression led to a clonal advantage, increased self-renewal potential, and blast-like morphology and distinct immunophenotype. Gene expression profiling revealed hedgehog signaling as a potential mechanism, with upregulation of GLI2 constituting a putative pharmacological target. Both primary hematopoietic cells and the t(8;21) positive AML cell line SKNO-1 showed increased sensitivity to the GLI inhibitor GANT61 when expressing CSF3R T618I. Our findings suggest that during leukemogenesis, the RUNX1-RUNXT1 fusion and CSF3R mutation act in a synergistic manner to alter hedgehog signaling, which can be exploited therapeutically.

4.
Hypertension ; 80(7): 1555-1567, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37125608

RESUMO

BACKGROUND: Primary aldosteronism is frequently caused by an adrenocortical aldosterone-producing adenoma (APA) carrying a somatic mutation that drives aldosterone overproduction. APAs with a mutation in KCNJ5 (APA-KCNJ5MUT) are characterized by heterogeneous CYP11B2 (aldosterone synthase) expression, a particular cellular composition and larger tumor diameter than those with wild-type KCNJ5 (APA-KCNJ5WT). We exploited these differences to decipher the roles of transcriptome and metabolome reprogramming in tumor pathogenesis. METHODS: Consecutive adrenal cryosections (7 APAs and 7 paired adjacent adrenal cortex) were analyzed by spatial transcriptomics (10x Genomics platform) and metabolomics (in situ matrix-assisted laser desorption/ionization mass spectrometry imaging) co-integrated with CYP11B2 immunohistochemistry. RESULTS: We identified intratumoral transcriptional heterogeneity that delineated functionally distinct biological pathways. Common transcriptomic signatures were established across all APA specimens which encompassed 2 distinct transcriptional profiles in CYP11B2-immunopositive regions (CYP11B2-type 1 or 2). The CYP11B2-type 1 signature was characterized by zona glomerulosa gene markers and was detected in both APA-KCNJ5MUT and APA-KCNJ5WT. The CYP11B2-type 2 signature displayed markers of the zona fasciculata or reticularis and predominated in APA-KCNJ5MUT. Metabolites that promote oxidative stress and cell death accumulated in APA-KCNJ5WT. In contrast, antioxidant metabolites were abundant in APA-KCNJ5MUT. Finally, APA-like cell subpopulations-negative for CYP11B2 gene expression-were identified in adrenocortical tissue adjacent to APAs suggesting the existence of tumor precursor states. CONCLUSIONS: Our findings provide insight into intra- and intertumoral transcriptional heterogeneity and support a role for prooxidant versus antioxidant systems in APA pathogenesis highlighting genotype-dependent capacities for tumor expansion.


Assuntos
Adenoma , Neoplasias do Córtex Suprarrenal , Adenoma Adrenocortical , Hiperaldosteronismo , Humanos , Aldosterona/metabolismo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismo , Antioxidantes , Multiômica , Hiperaldosteronismo/metabolismo , Adenoma Adrenocortical/metabolismo , Genótipo , Mutação , Adenoma/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/complicações
5.
Nat Commun ; 13(1): 5464, 2022 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-36115853

RESUMO

Schlafen 11 (SLFN11) is an interferon-inducible antiviral restriction factor with tRNA endoribonuclease and DNA binding functions. It is recruited to stalled replication forks in response to replication stress and inhibits replication of certain viruses such as the human immunodeficiency virus 1 (HIV-1) by modulating the tRNA pool. SLFN11 has been identified as a predictive biomarker in cancer, as its expression correlates with a beneficial response to DNA damage inducing anticancer drugs. However, the mechanism and interdependence of these two functions are largely unknown. Here, we present cryo-electron microscopy (cryo-EM) structures of human SLFN11 in its dimeric apoenzyme state, bound to tRNA and in complex with single-strand DNA. Full-length SLFN11 neither hydrolyses nor binds ATP and the helicase domain appears in an autoinhibited state. Together with biochemical and structure guided mutagenesis studies, our data give detailed insights into the mechanism of endoribonuclease activity as well as suggestions on how SLFN11 may block stressed replication forks.


Assuntos
Antineoplásicos , Antivirais , Microscopia Crioeletrônica , Endorribonucleases , Proteínas Nucleares , Trifosfato de Adenosina , Antineoplásicos/metabolismo , Antivirais/metabolismo , Apoenzimas , DNA , Endorribonucleases/genética , Endorribonucleases/metabolismo , Humanos , Interferons , Proteínas Nucleares/metabolismo , RNA de Transferência/metabolismo
6.
Nat Commun ; 13(1): 5586, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151076

RESUMO

Antibodies against the spike protein of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can drive adaptive evolution in immunocompromised patients with chronic infection. Here we longitudinally analyze SARS-CoV-2 sequences in a B cell-depleted, lymphoma patient with chronic, ultimately fatal infection, and identify three mutations in the spike protein that dampen convalescent plasma-mediated neutralization of SARS-CoV-2. Additionally, four mutations emerge in non-spike regions encoding three CD8 T cell epitopes, including one nucleoprotein epitope affected by two mutations. Recognition of each mutant peptide by CD8 T cells from convalescent donors is reduced compared to its ancestral peptide, with additive effects resulting from double mutations. Querying public SARS-CoV-2 sequences shows that these mutations have independently emerged as homoplasies in circulating lineages. Our data thus suggest that potential impacts of CD8 T cells on SARS-CoV-2 mutations, at least in those with humoral immunodeficiency, warrant further investigation to inform on vaccine design.


Assuntos
COVID-19 , Linfoma , Vacinas , Linfócitos T CD8-Positivos , COVID-19/terapia , Epitopos de Linfócito T/genética , Humanos , Imunização Passiva , Mutação , Nucleoproteínas/genética , Peptídeos/genética , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Soroterapia para COVID-19
7.
EMBO J ; 41(17): e111608, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35833542

RESUMO

The SARS-CoV-2 infection cycle is a multistage process that relies on functional interactions between the host and the pathogen. Here, we repurposed antiviral drugs against both viral and host enzymes to pharmaceutically block methylation of the viral RNA 2'-O-ribose cap needed for viral immune escape. We find that the host cap 2'-O-ribose methyltransferase MTr1 can compensate for loss of viral NSP16 methyltransferase in facilitating virus replication. Concomitant inhibition of MTr1 and NSP16 efficiently suppresses SARS-CoV-2 replication. Using in silico target-based drug screening, we identify a bispecific MTr1/NSP16 inhibitor with anti-SARS-CoV-2 activity in vitro and in vivo but with unfavorable side effects. We further show antiviral activity of inhibitors that target independent stages of the host SAM cycle providing the methyltransferase co-substrate. In particular, the adenosylhomocysteinase (AHCY) inhibitor DZNep is antiviral in in vitro, in ex vivo, and in a mouse infection model and synergizes with existing COVID-19 treatments. Moreover, DZNep exhibits a strong immunomodulatory effect curbing infection-induced hyperinflammation and reduces lung fibrosis markers ex vivo. Thus, multispecific and metabolic MTase inhibitors constitute yet unexplored treatment options against COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Animais , Antivirais/farmacologia , Inflamação/tratamento farmacológico , Metiltransferases/metabolismo , Camundongos , Capuzes de RNA/metabolismo , RNA Viral/genética , Ribose , Proteínas não Estruturais Virais/genética
8.
J Virol ; 96(11): e0059422, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35543509

RESUMO

It has recently been shown that an early SARS-CoV-2 isolate (NL-02-2020) hijacks interferon-induced transmembrane proteins (IFITMs) for efficient replication in human lung cells, cardiomyocytes, and gut organoids. To date, several "variants of concern" (VOCs) showing increased infectivity and resistance to neutralization have emerged and globally replaced the early viral strains. Here, we determined whether the five current SARS-CoV-2 VOCs (Alpha, Beta, Gamma, Delta, and Omicron) maintained the dependency on IFITM proteins for efficient replication. We found that depletion of IFITM2 strongly reduces viral RNA production by all VOCs in the human epithelial lung cancer cell line Calu-3. Silencing of IFITM1 had modest effects, while knockdown of IFITM3 resulted in an intermediate phenotype. Strikingly, depletion of IFITM2 generally reduced infectious virus production by more than 4 orders of magnitude. In addition, an antibody directed against the N terminus of IFITM2 inhibited SARS-CoV-2 VOC replication in induced pluripotent stem cell (iPSC)-derived alveolar epithelial type II cells, thought to represent major viral target cells in the lung. In conclusion, endogenously expressed IFITM proteins (especially IFITM2) are critical cofactors for efficient replication of genuine SARS-CoV-2 VOCs, including the currently dominant Omicron variant. IMPORTANCE Recent data indicate that SARS-CoV-2 requires endogenously expressed IFITM proteins for efficient infection. However, the results were obtained with an early SARS-CoV-2 isolate. Thus, it remained to be determined whether IFITMs are also important cofactors for infection of emerging SARS-CoV-2 VOCs that outcompeted the original strains in the meantime. This includes the Omicron VOC, which currently dominates the pandemic. Here, we show that depletion of endogenous IFITM2 expression almost entirely prevents productive infection of Alpha, Beta, Gamma, Delta, and Omicron SARS-CoV-2 VOCs in human lung cells. In addition, an antibody targeting the N terminus of IFITM2 inhibited SARS-CoV-2 VOC replication in iPSC-derived alveolar epithelial type II cells. Our results show that SARS-CoV-2 VOCs, including the currently dominant Omicron variant, are strongly dependent on IFITM2 for efficient replication, suggesting a key proviral role of IFITMs in viral transmission and pathogenicity.


Assuntos
Pulmão , Proteínas de Membrana , SARS-CoV-2 , Replicação Viral , COVID-19/virologia , Linhagem Celular Tumoral , Humanos , Pulmão/virologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Internalização do Vírus
9.
Med Oncol ; 39(6): 104, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35397689

RESUMO

Limited knowledge exists on the effectiveness of preventive preparedness plans for the care of outpatient cancer patients during epidemics or pandemics. To ensure adequate, timely and continuous clinical care for this highly vulnerable population, we propose the establishment of preventive standard safety protocols providing effective early phase identification of outbreaks at outpatient cancer facilities and communicating adapted standards of care. The prospective cohort study Protect-CoV conducted at the LMU Klinikum from mid-March to June 2020 investigated the effectiveness of a rapid, proactive and methodical response to protect patients and interrupt SARS-CoV-2 transmission chains during the first pandemic wave. The implemented measures reduced the risk of infection of individual cancer patients and ensured safe adjunctive infusion therapy in an outpatient setting during the early COVID-19 pandemic. In addition to the immediate implementation of standard hygiene procedures, our results underscore the importance of routine PCR testing for the identification of asymptomatic or pre-symptomatic COVID-19 cases and immediate tracing of positive cases and their contacts. While more prospective controlled studies are needed to confirm these results, our study illustrates the importance of including preventative testing and tracing measures in the standard risk reduction procedures at all out patient cancer centers.


Assuntos
COVID-19 , Pandemias , Instituições de Assistência Ambulatorial , Estudos de Coortes , Humanos , Pandemias/prevenção & controle , Estudos Prospectivos , Comportamento de Redução do Risco , SARS-CoV-2
10.
J Neurol ; 269(8): 4396-4403, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35307755

RESUMO

BACKGROUND AND PURPOSE: With aging population, there is an increase of atrial fibrillation (AF) and other vascular risk factors. We investigated trends in stroke severity at hospital admission with respect to AF and other risk factors in a prospective national stroke registry from 2005 to 2020. METHODS: Data from the prospective Austrian Stroke Unit Registry were used to study demographic and clinical factors associated with the change in admission stroke severity over years. Time trends in admission stroke severity of patients with pre-stroke modified Rankin Score ≤ 3 were investigated with respect to clinical variables and predefined age groups 18-54, 55-64, 65-74, 75-84 and ≥ 85 years. Time trends were studied using robust generalized linear models assuming normal distribution with a log link. Stroke severity on admission was assessed according to the National Institutes of Health Stroke Scale Score (NIHSS). RESULTS: In total, 140,312 patients with acute ischemic stroke were included in the analysis. Within the study period, mean patients' age increased from 70 to 72 years (p < 0.001) and median NIHSS at admission decreased from 4 to 3 (p < 0.001). The frequency of AF increased from 25 to 32% (p < 0.001). The decrease in median admission NIHSS was evident in all relevant subgroups but more pronounced in patients with risk factors including AF, diabetes, hypercholesterolemia, smoking, elderly patients and those with pre-stroke disability. CONCLUSION: Despite an aging population and generally increasing AF frequency, we observed a consistent trend towards less disabling strokes on admission.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Áustria/epidemiologia , Isquemia Encefálica/complicações , Humanos , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/etiologia
11.
Front Immunol ; 13: 820843, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222398

RESUMO

Objectives: Endoprosthetic loosening still plays a major role in orthopaedic and dental surgery and includes various cellular immune processes within peri-implant tissues. Although the dental and orthopaedic processes vary in certain parts, the clinical question arises whether there are common immune regulators of implant loosening. Analyzing the key gene expressions common to both processes reveals the mechanisms of osteoclastogenesis within periprosthetic tissues of orthopaedic and dental origin. Methods: Donor peripheral blood mononuclear cells (PBMCs) and intraoperatively obtained periprosthetic fibroblast-like cells (PPFs) were (co-)cultured with [± macrophage-colony stimulating factor (MCSF) and Receptor Activator of NF-κB ligand (RANKL)] in transwell and monolayer culture systems and examined for osteoclastogenic regulations [MCSF, RANKL, osteoprotegerin (OPG), and tumor necrosis factor alpha (TNFα)] as well as the ability of bone resorption. Sequencing analysis compared dental and orthopaedic (co-)cultures. Results: Monolayer co-cultures of both origins expressed high levels of OPG, resulting in inhibition of osteolysis shown by resorption assay on dentin. The high OPG-expression, low RANKL/OPG ratios and a resulting inhibition of osteolysis were displayed by dental and orthopaedic PPFs in monolayer even in the presence of MCSF and RANKL, acting as osteoprotective and immunoregulatory cells. The osteoprotective function was only observed in monolayer cultures of dental and orthopaedic periprosthetic cells and downregulated in the transwell system. In transwell co-cultures of PBMCs/PPFs profound changes of gene expression, with a significant decrease of OPG (20-fold dental versus 100 fold orthopaedic), were identified. Within transwell cultures, which offer more in vivo like conditions, RANKL/OPG ratios displayed similar high levels to the original periprosthetic tissue. For dental and orthopaedic implant loosening, overlapping findings in principal component and heatmap analysis were identified. Conclusions: Thus, periprosthetic osteoclastogenesis may be a correlating immune process in orthopaedic and dental implant failure leading to comparable reactions with regard to osteoclast formation. The transwell cultures system may provide an in vivo like model for the exploration of orthopaedic and dental implant loosening.


Assuntos
Implantes Dentários , Osteólise , Regulação da Expressão Gênica , Humanos , Leucócitos Mononucleares , Osteoclastos/metabolismo , Osteólise/genética , Osteólise/metabolismo
12.
Br J Haematol ; 196(6): 1381-1387, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34967008

RESUMO

Relapsed follicular lymphoma (FL) can arise from common progenitor cells (CPCs). Conceptually, CPC-defining mutations are somatic alterations shared by the initial and relapsed tumours, mostly B-cell leukaemia/lymphoma 2 (BCL2)/immunoglobulin heavy locus (IGH) translocations and other recurrent gene mutations. Through complementary approaches for highly sensitive mutation detection, we do not find CPC-defining mutations in highly purified BCL2/IGH-negative haematopoietic progenitor cells in clinical remission samples from three patients with relapsed FL. Instead, we find cells harbouring the same BCL2/IGH translocation but lacking CREB binding protein (CREBBP), lysine methyltransferase 2D (KMT2D) and other recurrent gene mutations. Thus, (i) the BCL2/IGH translocation can precede CPC-defining mutations in human FL, and (ii) BCL2/IGH-translocated cells can persist in clinical remission.


Assuntos
Linfoma de Células B , Linfoma Folicular , Células-Tronco Hematopoéticas/metabolismo , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Linfoma de Células B/genética , Linfoma Folicular/patologia , Mutação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Translocação Genética
13.
Graefes Arch Clin Exp Ophthalmol ; 260(5): 1789-1797, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34962592

RESUMO

PURPOSE: To detect SARS-CoV-2 RNA in post-mortem human eyes. Ocular symptoms are common in patients with COVID-19. In some cases, they can occur before the onset of respiratory and other symptoms. Accordingly, SARS-CoV-2 RNA has been detected in conjunctival samples and tear film of patients suffering from COVID-19. However, the detection and clinical relevance of intravitreal SARS-CoV-2 RNA still remain unclear due to so far contradictory reports in the literature. METHODS: In our study 20 patients with confirmed diagnosis of COVID-19 were evaluated post-mortem to assess the conjunctival and intraocular presence of SARS-CoV-2 RNA using sterile pulmonary and conjunctival swabs as well as intravitreal biopsies (IVB) via needle puncture. SARS-CoV-2 PCR and whole genome sequencing from the samples of the deceased patients were performed. Medical history and comorbidities of all subjects were recorded and analyzed for correlations with viral data. RESULTS: SARS-CoV-2 RNA was detected in 10 conjunctival (50%) and 6 vitreal (30%) samples. SARS-CoV-2 whole genome sequencing showed the distribution of cases largely reflecting the frequency of circulating lineages in the Munich area at the time of examination with no preponderance of specific variants. Especially there was no association between the presence of SARS-CoV-2 RNA in IVBs and infection with the variant of concern (VOC) alpha. Viral load in bronchial samples correlated positively with load in conjunctiva but not the vitreous. CONCLUSION: SARS-CoV-2 RNA can be detected post mortem in conjunctival tissues and IVBs. This is relevant to the planning of ophthalmologic surgical procedures in COVID-19 patients, such as pars plana vitrectomy or corneal transplantation. Furthermore, not only during surgery but also in an outpatient setting it is important to emphasize the need for personal protection in order to avoid infection and spreading of SARS-CoV-2. Prospective studies are needed, especially to determine the clinical relevance of conjunctival and intravitreal SARS-CoV-2 detection concerning intraocular affection in active COVID-19 state and in post-COVID syndrome.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Túnica Conjuntiva , Humanos , RNA Viral/genética , SARS-CoV-2/genética , Lágrimas/química
14.
Haematologica ; 107(1): 100-111, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34134471

RESUMO

Identification of fusion genes in clinical routine is mostly based on cytogenetics and targeted molecular genetics, such as metaphase karyotyping, fluorescence in situ hybridization and reverse-transcriptase polymerase chain reaction. However, sequencing technologies are becoming more important in clinical routine as processing time and costs per sample decrease. To evaluate the performance of fusion gene detection by RNAsequencing compared to standard diagnostic techniques, we analyzed 806 RNA-sequencing samples from patients with acute myeloid leukemia using two state-of-the-art software tools, namely Arriba and FusionCatcher. RNA-sequencing detected 90% of fusion events that were reported by routine with high evidence, while samples in which RNA-sequencing failed to detect fusion genes had overall lower and inhomogeneous sequence coverage. Based on properties of known and unknown fusion events, we developed a workflow with integrated filtering strategies for the identification of robust fusion gene candidates by RNA-sequencing. Thereby, we detected known recurrent fusion events in 26 cases that were not reported by routine and found discrepancies in evidence for known fusion events between routine and RNA-sequencing in three cases. Moreover, we identified 157 fusion genes as novel robust candidates and comparison to entries from ChimerDB or Mitelman Database showed novel recurrence of fusion genes in 14 cases. Finally, we detected the novel recurrent fusion gene NRIP1- MIR99AHG resulting from inv(21)(q11.2;q21.1) in nine patients (1.1%) and LTN1-MX1 resulting from inv(21)(q21.3;q22.3) in two patients (0.25%). We demonstrated that NRIP1-MIR99AHG results in overexpression of the 3' region of MIR99AHG and the disruption of the tricistronic miRNA cluster miR-99a/let-7c/miR-125b-2. Interestingly, upregulation of MIR99AHG and deregulation of the miRNA cluster, residing in the MIR99AHG locus, are known mechanisms of leukemogenesis in acute megakaryoblastic leukemia. Our findings demonstrate that RNA-sequencing has a strong potential to improve the systematic detection of fusion genes in clinical applications and provides a valuable tool for fusion discovery.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Criança , Rearranjo Gênico , Humanos , Hibridização in Situ Fluorescente , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Proteínas de Fusão Oncogênica/genética , Análise de Sequência de RNA , Translocação Genética
15.
Elife ; 102021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33683199

RESUMO

Eukaryotic DNA replication initiates during S phase from origins that have been licensed in the preceding G1 phase. Here, we compare ChIP-seq profiles of the licensing factors Orc2, Orc3, Mcm3, and Mcm7 with gene expression, replication timing, and fork directionality profiles obtained by RNA-seq, Repli-seq, and OK-seq. Both, the origin recognition complex (ORC) and the minichromosome maintenance complex (MCM) are significantly and homogeneously depleted from transcribed genes, enriched at gene promoters, and more abundant in early- than in late-replicating domains. Surprisingly, after controlling these variables, no difference in ORC/MCM density is detected between initiation zones, termination zones, unidirectionally replicating regions, and randomly replicating regions. Therefore, ORC/MCM density correlates with replication timing but does not solely regulate the probability of replication initiation. Interestingly, H4K20me3, a histone modification proposed to facilitate late origin licensing, was enriched in late-replicating initiation zones and gene deserts of stochastic replication fork direction. We discuss potential mechanisms specifying when and where replication initiates in human cells.


Assuntos
Replicação do DNA/genética , Proteínas de Manutenção de Minicromossomo/genética , Modelos Genéticos , Complexo de Reconhecimento de Origem/genética , Linhagem Celular Tumoral , Humanos , Proteínas de Manutenção de Minicromossomo/metabolismo , Complexo de Reconhecimento de Origem/metabolismo
16.
Nucleic Acids Res ; 49(6): 3217-3241, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33675667

RESUMO

Epstein-Barr virus (EBV), a herpes virus also termed HHV 4 and the first identified human tumor virus, establishes a stable, long-term latent infection in human B cells, its preferred host. Upon induction of EBV's lytic phase, the latently infected cells turn into a virus factory, a process that is governed by EBV. In the lytic, productive phase, all herpes viruses ensure the efficient induction of all lytic viral genes to produce progeny, but certain of these genes also repress the ensuing antiviral responses of the virally infected host cells, regulate their apoptotic death or control the cellular transcriptome. We now find that EBV causes previously unknown massive and global alterations in the chromatin of its host cell upon induction of the viral lytic phase and prior to the onset of viral DNA replication. The viral initiator protein of the lytic cycle, BZLF1, binds to >105 binding sites with different sequence motifs in cellular chromatin in a concentration dependent manner implementing a binary molar switch probably to prevent noise-induced erroneous induction of EBV's lytic phase. Concomitant with DNA binding of BZLF1, silent chromatin opens locally as shown by ATAC-seq experiments, while previously wide-open cellular chromatin becomes inaccessible on a global scale within hours. While viral transcripts increase drastically, the induction of the lytic phase results in a massive reduction of cellular transcripts and a loss of chromatin-chromatin interactions of cellular promoters with their distal regulatory elements as shown in Capture-C experiments. Our data document that EBV's lytic cycle induces discrete early processes that disrupt the architecture of host cellular chromatin and repress the cellular epigenome and transcriptome likely supporting the efficient de novo synthesis of this herpes virus.


Assuntos
Cromatina/virologia , Regulação da Expressão Gênica , Herpesvirus Humano 4/fisiologia , Transativadores/metabolismo , Transcriptoma , Sítios de Ligação , Linhagem Celular , Cromatina/química , Cromatina/metabolismo , DNA/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Humanos
18.
J Neurol Sci ; 418: 117033, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32871511

RESUMO

BACKGROUND: Autonomic nervous system changes have been associated with outcome after intracerebral hemorrhage (ICH) previously. We aimed to investigate the association of heart rate entropy (HRE) with mortality after ICH. METHODS: Sample HRE, heart rate variability and baroreflex sensitivity were examined in consecutive ICH patients. Hematoma volume, intraventricular hemorrhage, infratentorial origin, consciousness impairment and age were combined into standard ICH score. RESULTS: In 47 patients suffering ICH (mean age 61 years, median hemorrhage volume 38 mL) the areas under the curve (AUC) for mortality were 0.86, 0.83, 0.76, 0.74, 0.72 and 0.7 for HRE, ICH-score, normalized low frequency powers, low frequency/high frequency powers ratio, normalized high frequency powers and BRS, respectively. HRE and ICH score were associated with mortality independently (adjusted odd ratio (aOR) 0.09, 95% confidence interval (CI) 0.1-0.8, p = .03 and aOR 2.6, CI 1.03-6.6, p = .04). Combining ICH score with HRE into a novel score resulted in an AUC of 0.94, CI 0.88-0.99, p < .001. CONCLUSION: Compared to several autonomic markers HRE seems to bear the largest amount of information on death probability after ICH. Moreover, HRE may predict mortality comparable to ICH score. Combining HRE with ICH score may increase the predictive performance for mortality after ICH.


Assuntos
Hemorragia Cerebral , Hematoma , Sistema Nervoso Autônomo , Hemorragia Cerebral/diagnóstico por imagem , Entropia , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade
19.
Sci Rep ; 10(1): 12241, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699244

RESUMO

Autophagy is a cellular homeostatic pathway with functions ranging from cytoplasmic protein turnover to immune defense. Therapeutic modulation of autophagy has been demonstrated to positively impact the outcome of autophagy-dysregulated diseases such as cancer or microbial infections. However, currently available agents lack specificity, and new candidates for drug development or potential cellular targets need to be identified. Here, we present an improved method to robustly detect changes in autophagy in a high-throughput manner on a single cell level, allowing effective screening. This method quantifies eGFP-LC3B positive vesicles to accurately monitor autophagy. We have significantly streamlined the protocol and optimized it for rapid quantification of large numbers of cells in little time, while retaining accuracy and sensitivity. Z scores up to 0.91 without a loss of sensitivity demonstrate the robustness and aptness of this approach. Three exemplary applications outline the value of our protocols and cell lines: (I) Examining autophagy modulating compounds on four different cell types. (II) Monitoring of autophagy upon infection with e.g. measles or influenza A virus. (III) CRISPR/Cas9 screening for autophagy modulating factors in T cells. In summary, we offer ready-to-use protocols to generate sensitive autophagy reporter cells and quantify autophagy in high-throughput assays.


Assuntos
Autofagia/imunologia , Ensaios de Triagem em Larga Escala/métodos , Mamíferos/imunologia , Animais , Sistemas CRISPR-Cas/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Células HeLa , Humanos , Infecções/imunologia , Células Jurkat , Linfócitos T/imunologia , Células THP-1
20.
EBioMedicine ; 57: 102862, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32629392

RESUMO

BACKGROUND: Bone marrow stem cell clonal dysfunction by somatic mutation is suspected to affect post-infarction myocardial regeneration after coronary bypass surgery (CABG). METHODS: Transcriptome and variant expression analysis was studied in the phase 3 PERFECT trial post myocardial infarction CABG and CD133+ bone marrow derived hematopoetic stem cells showing difference in left ventricular ejection fraction (∆LVEF) myocardial regeneration Responders (n=14; ∆LVEF +16% day 180/0) and Non-responders (n=9; ∆LVEF -1.1% day 180/0). Subsequently, the findings have been validated in an independent patient cohort (n=14) as well as in two preclinical mouse models investigating SH2B3/LNK antisense or knockout deficient conditions. FINDINGS: 1. Clinical: R differed from NR in a total of 161 genes in differential expression (n=23, q<0•05) and 872 genes in coexpression analysis (n=23, q<0•05). Machine Learning clustering analysis revealed distinct RvsNR preoperative gene-expression signatures in peripheral blood acorrelated to SH2B3 (p<0.05). Mutation analysis revealed increased specific variants in RvsNR. (R: 48 genes; NR: 224 genes). 2. Preclinical:SH2B3/LNK-silenced hematopoietic stem cell (HSC) clones displayed significant overgrowth of myeloid and immune cells in bone marrow, peripheral blood, and tissue at day 160 after competitive bone-marrow transplantation into mice. SH2B3/LNK-/- mice demonstrated enhanced cardiac repair through augmenting the kinetics of bone marrow-derived endothelial progenitor cells, increased capillary density in ischemic myocardium, and reduced left ventricular fibrosis with preserved cardiac function. 3. VALIDATION: Evaluation analysis in 14 additional patients revealed 85% RvsNR (12/14 patients) prediction accuracy for the identified biomarker signature. INTERPRETATION: Myocardial repair is affected by HSC gene response and somatic mutation. Machine Learning can be utilized to identify and predict pathological HSC response. FUNDING: German Ministry of Research and Education (BMBF): Reference and Translation Center for Cardiac Stem Cell Therapy - FKZ0312138A and FKZ031L0106C, German Ministry of Research and Education (BMBF): Collaborative research center - DFG:SFB738 and Center of Excellence - DFG:EC-REBIRTH), European Social Fonds: ESF/IV-WM-B34-0011/08, ESF/IV-WM-B34-0030/10, and Miltenyi Biotec GmbH, Bergisch-Gladbach, Germany. Japanese Ministry of Health : Health and Labour Sciences Research Grant (H14-trans-001, H17-trans-002) TRIAL REGISTRATION: ClinicalTrials.gov NCT00950274.


Assuntos
Antígeno AC133/genética , Transplante de Medula Óssea/métodos , Doença da Artéria Coronariana/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Isquemia Miocárdica/terapia , Adolescente , Adulto , Idoso , Células da Medula Óssea/citologia , Senescência Celular/genética , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/fisiopatologia , Feminino , Coração/crescimento & desenvolvimento , Coração/fisiopatologia , Células-Tronco Hematopoéticas/citologia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/genética , Isquemia Miocárdica/patologia , Regeneração/genética , Adulto Jovem
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