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1.
Front Immunol ; 14: 1219165, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915564

RESUMO

Introduction: Chimeric antigen receptor-engineered T cells (CAR-Ts) are investigated in various clinical trials for the treatment of cancer entities beyond hematologic malignancies. A major hurdle is the identification of a target antigen with high expression on the tumor but no expression on healthy cells, since "on-target/off-tumor" cytotoxicity is usually intolerable. Approximately 90% of carcinomas and leukemias are positive for the Thomsen-Friedenreich carbohydrate antigen CD176, which is associated with tumor progression, metastasis and therapy resistance. In contrast, CD176 is not accessible for ligand binding on healthy cells due to prolongation by carbohydrate chains or sialylation. Thus, no "on-target/off-tumor" cytotoxicity and low probability of antigen escape is expected for corresponding CD176-CAR-Ts. Methods: Using the anti-CD176 monoclonal antibody (mAb) Nemod-TF2, the presence of CD176 was evaluated on multiple healthy or cancerous tissues and cells. To target CD176, we generated two different 2nd generation CD176-CAR constructs differing in spacer length. Their specificity for CD176 was tested in reporter cells as well as primary CD8+ T cells upon co-cultivation with CD176+ tumor cell lines as models for CD176+ blood and solid cancer entities, as well as after unmasking CD176 on healthy cells by vibrio cholerae neuraminidase (VCN) treatment. Following that, both CD176-CARs were thoroughly examined for their ability to initiate target-specific T-cell signaling and activation, cytokine release, as well as cytotoxicity. Results: Specific expression of CD176 was detected on primary tumor tissues as well as on cell lines from corresponding blood and solid cancer entities. CD176-CARs mediated T-cell signaling (NF-κB activation) and T-cell activation (CD69, CD137 expression) upon recognition of CD176+ cancer cell lines and unmasked CD176, whereby a short spacer enabled superior target recognition. Importantly, they also released effector molecules (e.g. interferon-γ, granzyme B and perforin), mediated cytotoxicity against CD176+ cancer cells, and maintained functionality upon repetitive antigen stimulation. Here, CD176L-CAR-Ts exhibited slightly higher proliferation and mediator-release capacities. Since both CD176-CAR-Ts did not react towards CD176- control cells, their response proved to be target-specific. Discussion: Genetically engineered CD176-CAR-Ts specifically recognize CD176 which is widely expressed on cancer cells. Since CD176 is masked on most healthy cells, this antigen and the corresponding CAR-Ts represent a promising approach for the treatment of various blood and solid cancers while avoiding "on-target/off-tumor" cytotoxicity.


Assuntos
Linfócitos T CD8-Positivos , Leucemia , Humanos , Antígenos Glicosídicos Associados a Tumores , Carboidratos
2.
J Immunol ; 209(6): 1048-1058, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35985788

RESUMO

In IgA vasculitis (IgAV) perivascular deposition of IgA1 immune complexes (IgA-ICs) is traditionally considered the fundamental trigger for polymorphonuclear neutrophil (PMN)-mediated damage. We propose that IgA-IC deposition, although mandatory, is not sufficient alone for IgAV. Serum IgA-IC levels and IgA-IC binding to PMNs were quantified in IgAV patients and controls. Activation of PMNs was evaluated by neutrophil extracellular trap (NET) release, adherence, and cytotoxicity assays and in a flow system to mirror conditions at postcapillary venules. In vitro results were related to findings in biopsies and a mouse vasculitis model. During acute IgAV flares we observed elevated serum levels of IgA-ICs and increased IgA-IC binding to circulating PMNs. This IgA-IC binding primed PMNs with consequent lowering of the threshold for NETosis, demonstrated by significantly higher release of NETs from PMNs activated in vitro and PMNs from IgAV patients with flares compared with surface IgA-negative PMNs after flares. Blocking of FcαRI abolished these effects, and complement was not essential. In the flow system, marked NETosis only occurred after PMNs had adhered to activated endothelial cells. IgA-IC binding enhanced this PMN tethering and consequent NET-mediated endothelial cell injury. Reflecting these in vitro findings, we visualized NETs in close proximity to endothelial cells and IgA-coated PMNs in tissue sections of IgAV patients. Inhibition of NET formation and knockout of myeloperoxidase in a murine model of IC vasculitis significantly reduced vessel damage in vivo. Binding of IgA-ICs during active IgAV primes PMNs and promotes vessel injury through increased adhesion of PMNs to the endothelium and enhanced NETosis.


Assuntos
Vasculite por IgA , Vasculite , Animais , Complexo Antígeno-Anticorpo/metabolismo , Células Endoteliais , Imunoglobulina A , Camundongos , Neutrófilos , Peroxidase/metabolismo
3.
J Invest Dermatol ; 141(12): 2820-2828, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34246620

RESUMO

Pathomechanisms in IgA pemphigus are assumed to rely on Fc-dependent cellular activation by antigen-specific IgA autoantibodies; however, models for the disease and more detailed pathophysiologic data are lacking. In this study, we aimed to establish in vitro models of disease for IgA pemphigus, allowing us to study the effects of the interaction of anti-keratinocyte IgA with cell surface FcαRs. Employing multiple in vitro assays, such as a skin cryosection assay and a human skin organ culture model, in this study, we present mechanistic data for the pathogenesis of IgA pemphigus, mediated by anti-desmoglein 3 IgA autoantibodies. Our results reveal that this disease is dependent on FcαR-mediated activation of leukocytes in the epidermis. Importantly, this cell-dependent pathology can be dose-dependently abrogated by peptide-mediated inhibition of FcαR:IgA-Fc interaction, as confirmed in an additional model for IgA-dependent disease, that is, IgA vasculitis. These data suggest that IgA pemphigus can be modeled in vitro and that IgA pemphigus and IgA vasculitis are FcαR-dependent disease entities that can be specifically targeted in these experimental systems.


Assuntos
Imunoglobulina A/imunologia , Neutrófilos/fisiologia , Pênfigo/etiologia , Receptores Fc/antagonistas & inibidores , Antígenos CD/fisiologia , Desmogleína 3/imunologia , Proteínas do Olho/farmacologia , Humanos , Pênfigo/imunologia , Fragmentos de Peptídeos/farmacologia , Receptores Fc/fisiologia
4.
Pigment Cell Melanoma Res ; 33(1): 63-73, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31402559

RESUMO

Ulceration of melanoma is associated with neutrophil infiltrates and lower survival rates opposite to non-ulcerated melanoma. Neutrophils release neutrophil extracellular traps (NETs) that are chromatin structures loaded with antimicrobial proteins. Since NETs have been correlated with tumor progression, we investigated whether NETs appear in melanoma and affect melanoma cells. Indeed, human primary melanoma biopsies revealed neutrophils releasing NETs in all of 27 ulcerated melanomas, whereas NETs were absent in all of 7 non-ulcerated melanomas. However, the quantity of intratumoral NETs did not correlate with tumor progression of melanoma. Interestingly, in vitro assays showed that melanoma cells attach to NETs via integrin-mediated adhesion and that NETs inhibit tumor cell migration. Moreover, co-culturing of NETs and melanoma cells had a cytotoxic effect on melanoma cells resulting in necrosis. Hence, we discovered in vitro an antineoplastic role of NETs in melanoma.


Assuntos
Armadilhas Extracelulares/metabolismo , Melanoma/metabolismo , Adesão Celular , Morte Celular , Linhagem Celular Tumoral , Movimento Celular , Humanos , Integrinas/metabolismo , Neutrófilos/patologia , Úlcera/patologia
5.
J Am Acad Dermatol ; 81(5): 1078-1085, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30902725

RESUMO

BACKGROUND: IgA vasculitis (IgAV) encompasses a systemic form involving kidneys, gut, skin, or joints, and a skin-limited form. One characteristic feature of systemic IgAV is deposition of galactose-deficient IgA1 (GD-IgA1) in kidneys (as in IgA nephropathy). The relevance of GD-IgA1 for cutaneous vasculitis is unknown. OBJECTIVE: We investigated whether GD-IgA1 is deposited perivascularly in systemic and also skin-limited IgAV and whether its serum levels differ between both forms. METHODS: In a case-control study, deposition of GD-IgA1 was analyzed immunohistochemically by KM55 antibody in skin biopsy specimens from 12 patients with skin-limited IgAV and 4 with systemic IgAV. GD-IgA1 levels were compared by enzyme-linked immunosorbent assay in sera from 15 patients each with skin-limited and systemic IgAV and from 11 healthy individuals. RESULTS: All biopsy samples from systemic IgAV, and also from skin-limited IgAV, revealed perivascular GD-IgA1 deposition. The average GD-IgA1 concentration in serum was significantly higher in systemic IgAV than in skin-limited IgAV, despite overlap between the groups. LIMITATIONS: Although high GD-IgA1 levels may be predictive of systemic IgAV, patient numbers were too low to determine cutoff values for systemic versus skin-limited IgAV. CONCLUSION: Perivascular GD-IgA1 deposition is a prerequisite for systemic and skin-limited IgAV; however, high GD-IgA1 levels in some patients with systemic IgAV suggest a dose-dependent effect of GD-IgA1 in IgAV.


Assuntos
Imunoglobulina A , Dermatopatias Vasculares/metabolismo , Pele/química , Pele/metabolismo , Vasculite/metabolismo , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/irrigação sanguínea , Dermatopatias Vasculares/sangue , Vasculite/sangue , Vasculite/imunologia
6.
Sci Rep ; 7(1): 7163, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28769061

RESUMO

The long non-coding RNA PARTICLE (Gene PARTICL- 'Promoter of MAT2A-Antisense RadiaTion Induced Circulating LncRNA) partakes in triple helix (triplex) formation, is transiently elevated following low dose irradiation and regulates transcription of its neighbouring gene - Methionine adenosyltransferase 2A. It now emerges that PARTICLE triplex sites are predicted in many different genes across all human chromosomes. In silico analysis identified additional regions for PARTICLE triplexes at >1600 genomic locations. Multiple PARTICLE triplexes are clustered predominantly within the human and mouse tumor suppressor WW Domain Containing Oxidoreductase (WWOX) gene. Surface plasmon resonance diffraction and electrophoretic mobility shift assays were consistent with PARTICLE triplex formation within human WWOX with high resolution imaging demonstrating its enrichment at this locus on chromosome 16. PARTICLE knockdown and over-expression resulted in inverse changes in WWOX transcripts levels with siRNA interference eliminating PARTICLEs elevated transcription to irradiation. The evidence for a second functional site of PARTICLE triplex formation at WWOX suggests that PARTICLE may form triplex-mediated interactions at multiple positions in the human genome including remote loci. These findings provide a mechanistic explanation for the ability of lncRNAs to regulate the expression of numerous genes distributed across the genome.


Assuntos
Genoma Humano , RNA Longo não Codificante/química , RNA Longo não Codificante/genética , Proteínas Supressoras de Tumor/genética , Oxidorredutase com Domínios WW/genética , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular , Cromossomos Humanos Par 16 , Suscetibilidade a Doenças , Epistasia Genética , Regulação da Expressão Gênica , Loci Gênicos , Genoma , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/genética , Transcrição Gênica
7.
Forensic Sci Int ; 278: 101-105, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28710938

RESUMO

INTRODUCTION: The lifestyle product 'Eezup!' appeared on the German market and promised to normalize energy metabolism. Among vitamins (B1, B2, B6, C, E and zinc), rice protein and fructose the addition of alcohol dehydrogenase and catalase enzymes is a novel approach. The product was advertised as capable of boosting the rate of alcohol elimination. METHODS: Seventeen subjects (11 men, 6 women, 19-58 years old), participated in a two-way crossover drinking study. Unfiltered wheat beer (4.4g% alcohol content) was drank within one hour to reach blood alcohol concentrations of 1‰ (1g/kg whole blood). On one day "Eezup!" was taken according to the manufacturer's instructions before and after drinking which was substituted for a placebo on the second test day. Blood samples were taken during 9h and ethanol and congener alcohols were determined. A comparison of Cmax, tmax, area under the curve (AUC) for ethanol and congener alcohols, and the hourly elimination rate of ethanol (ß60) was performed to investigate an effect of Eezup!. RESULTS: Ethanol concentrations (Cmax) were in the range of 0,63-1,00‰ (median 0,85‰) and 0.62-1.22‰ (median 0.84‰) in the placebo and "Eezup!" condition, respectively, and not statistically different. Also tmax (1-2.5h) and AUCs did not differ. The ethanol elimination rates were 0.16‰/h (0.14-0.19‰/h) and 0.17‰/h (0.14-0.22 ‰/h) in the placebo and "Eezup!" condition without significant difference. The pharmacokinetic parameters of the congener alcohols (1-propanol, isobutanol, 3-methyl-1-butanol, 2-methyl-1-butanol) as well as of methanol did also not differ. CONCLUSIONS: The results of the present study failed to show any effect of the sobering product "Eezup!" on the amount of ethanol and congener alcohols absorbed (Cmax, tmax, AUC) and on the ethanol elimination rate (ß60).


Assuntos
Intoxicação Alcoólica/prevenção & controle , Bebidas , Depressores do Sistema Nervoso Central/farmacocinética , Etanol/farmacocinética , 1-Propanol/sangue , Adulto , Cerveja , Butanóis/sangue , Depressores do Sistema Nervoso Central/sangue , Etanol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pentanóis/sangue , Adulto Jovem
8.
Sci Rep ; 7(1): 1790, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28496150

RESUMO

PARTICLE (Gene PARTICL- 'Promoter of MAT2A-Antisense RadiaTion Induced Circulating LncRNA) expression is transiently elevated following low dose irradiation typically encountered in the workplace and from natural sources. This long non-coding RNA recruits epigenetic silencers for cis-acting repression of its neighbouring Methionine adenosyltransferase 2A gene. It now emerges that PARTICLE operates as a trans-acting mediator of DNA and histone lysine methylation. Chromatin immunoprecipitation sequencing (ChIP-seq) and immunological evidence established elevated PARTICLE expression linked to increased histone 3 lysine 27 trimethylation. Live-imaging of dbroccoli-PARTICLE revealing its dynamic association with DNA methyltransferase 1 was confirmed by flow cytometry, immunoprecipitation and direct competitive binding interaction through electrophoretic mobility shift assay. Acting as a regulatory docking platform, the long non-coding RNA PARTICLE serves to interlink epigenetic modification machineries and represents a compelling innovative component necessary for gene silencing on a global scale.


Assuntos
Metilação de DNA , Histonas/metabolismo , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA/efeitos da radiação , Epistasia Genética , Perfilação da Expressão Gênica , Genoma Humano , Humanos , Metilação , Radiação Ionizante , Proteínas Supressoras de Tumor/genética , Oxidorredutase com Domínios WW/genética
9.
J Psychosom Obstet Gynaecol ; 37(4): 119-129, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27376660

RESUMO

INTRODUCTION: Antepartum risk and protective factors for postpartum depression (PPD; the most common mental disorder after childbirth besides postpartum anxiety), have been frequently investigated in cross-sectional studies, but less often longitudinally. This study examined linear and moderator effects of risk and protective factors for peripartum depression. First, we investigated the predictive power of risk factors (physical problems during pregnancy, pregnancy-related anxiety, stressful life events, dysfunctional self-consciousness (DSC)) and protective factors (resilience, social support) for antepartum depression (APD) and PPD. Second, as DSC plays an important role in major depression, we examined whether the protective factors moderate the association between the risk factors DSC and APD as well as PPD. METHODS: We conducted a prospective study with three measurement time points: six weeks antepartum (N = 297), as well as six weeks (N = 278) and twelve weeks (N = 266) postpartum. Direct and moderator effects on APD were analyzed using hierarchical regression analysis. Moderated mediation effects were investigated to explore whether the indirect, long-term effect of DSC on PPD six weeks after birth (PPD-6) and PPD twelve weeks after birth (PPD-12) is moderated by resilience. RESULTS: Predictors for APD were high DSC, high concerns about one's appearance, low resilience and low social support. Resilience buffered (weakened) the impact of DSC on APD and affected PPD-6 and PPD-12 indirectly through APD. DISCUSSION: The results suggest that PPD-12 is influenced directly and indirectly through PPD-6 by APD, but that this effect depends upon risk and protective factors, especially on the combined effects of resilience and DSC. The key finding of our study is the moderating (i.e. weakening) effect of resilience on the relationship between DSC and depression. Resilience and DSC may be an important issue for depression prevention and treatment programs in the peripartum period.


Assuntos
Depressão Pós-Parto/epidemiologia , Transtorno Depressivo Maior/epidemiologia , Complicações na Gravidez/epidemiologia , Adulto , Feminino , Alemanha/epidemiologia , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Fatores de Proteção , Fatores de Risco , Adulto Jovem
10.
J Affect Disord ; 191: 280-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26688497

RESUMO

BACKGROUND: There is first evidence that some personality characteristics raise the risk of postpartum depression (PPD). The present longitudinal study investigates whether dysfunctional perfectionism and avoidant personality style predict PPD, postpartum anxiety (PPA) and bonding impairment (BI) directly or indirectly through antepartum anxiety (APA) and antepartum depression (APD). METHODS: Pregnant women were recruited in two obstetric departments in Germany. The assessment occurred at two measurement time points: In the third trimester of pregnancy (N=297) and twelve weeks postpartum (N=266). Six questionnaires were administered during pregnancy: perfectionism, personality styles, anxiety, and depression. Postpartum, data on PPA, PPD and BI were collected. We conducted two path analyses in order to examine direct and indirect effects of the two personality characteristics on postpartum disorders. RESULTS: Testing for direct effects of dysfunctional perfectionism and avoidant personality style on PPD, PPA, and BI did not yield significant results. Instead, significant indirect effects were found: PPD, PPA, and BI were influenced indirectly by dysfunctional perfectionism and avoidant personality style via APD and APA. This model explained high portions of the variance of PPD, PPA, and impaired bonding. Each of the two personality characteristics explained a unique part of the outcome measures. The influence on BI was mediated by PPD. APD affected PPD and PPA more strongly than APA. LIMITATION: Path models with manifest (observed) variables may lead to measurement errors. Self-rating questionnaires may raise the problem of social desirability. CONCLUSION: Dysfunctional perfectionism and avoidant personality style are significant risk factors for PPD, PPA, and BI. Screenings of both variables, as well as of APA and APD, which mediated the effect of personality traits on postpartum syndromes, are necessary.


Assuntos
Transtornos de Ansiedade/psicologia , Ansiedade/psicologia , Depressão Pós-Parto/psicologia , Transtornos da Personalidade/psicologia , Período Pós-Parto/psicologia , Adulto , Depressão , Depressão Pós-Parto/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Relações Mãe-Filho/psicologia , Apego ao Objeto , Personalidade , Inventário de Personalidade , Gravidez , Terceiro Trimestre da Gravidez/psicologia , Prevalência , Fatores de Risco , Autorrelato , Adulto Jovem
11.
J Comp Neurol ; 522(10): 2377-96, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24435811

RESUMO

The nucleus geniculatus lateralis pars ventralis (GLv) is a prominent retinal target in all amniotes. In birds, it is in receipt of a dense and topographically organized retinal projection. The GLv is also the target of substantial and topographically organized projections from the optic tectum and the visual wulst (hyperpallium). Tectal and retinal afferents terminate homotopically within the external GLv-neuropil. Efferents from the GLv follow a descending course through the tegmentum and can be traced into the medial pontine nucleus. At present, the cells of origin of the Tecto-GLv projection are only partially described. Here we characterized the laminar location, morphology, projection pattern, and neurochemical identity of these cells by means of neural tracer injections and intracellular fillings in slice preparations and extracellular tracer injections in vivo. The Tecto-GLv projection arises from a distinct subset of layer 10 bipolar neurons, whose apical dendrites show a complex transverse arborization at the level of layer 7. Axons of these bipolar cells arise from the apical dendrites and follow a course through the optic tract to finally form very fine and restricted terminal endings inside the GLv-neuropil. Double-label experiments showed that these bipolar cells were choline acetyltransferase (ChAT)-immunoreactive. Our results strongly suggest that Tecto-GLv neurons form a pathway by which integrated tectal activity rapidly feeds back to the GLv and exerts a focal cholinergic modulation of incoming retinal inputs.


Assuntos
Encéfalo/citologia , Galinhas/anatomia & histologia , Columbidae/anatomia & histologia , Neurônios/citologia , Vias Visuais/citologia , Animais , Axônios/metabolismo , Encéfalo/metabolismo , Galinhas/metabolismo , Colina O-Acetiltransferase/metabolismo , Columbidae/metabolismo , Dendritos/metabolismo , Corpos Geniculados/citologia , Corpos Geniculados/metabolismo , Imuno-Histoquímica , Técnicas de Rastreamento Neuroanatômico , Neurônios/metabolismo , Colículos Superiores/citologia , Colículos Superiores/metabolismo , Técnicas de Cultura de Tecidos , Vias Visuais/metabolismo
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