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1.
Glia ; 70(5): 935-960, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35092321

RESUMO

A key pathological process in Parkinson's disease (PD) is the transneuronal spreading of α-synuclein. Alpha-synuclein (α-syn) is a presynaptic protein that, in PD, forms pathological inclusions. Other hallmarks of PD include neurodegeneration and microgliosis in susceptible brain regions. Whether it is primarily transneuronal spreading of α-syn particles, inclusion formation, or other mechanisms, such as inflammation, that cause neurodegeneration in PD is unclear. We used a model of spreading of α-syn induced by striatal injection of α-syn preformed fibrils into the mouse striatum to address this question. We performed quantitative analysis for α-syn inclusions, neurodegeneration, and microgliosis in different brain regions, and generated gene expression profiles of the ventral midbrain, at two different timepoints after disease induction. We observed significant neurodegeneration and microgliosis in brain regions not only with, but also without α-syn inclusions. We also observed prominent microgliosis in injured brain regions that did not correlate with neurodegeneration nor with inclusion load. Using longitudinal gene expression profiling, we observed early gene expression changes, linked to neuroinflammation, that preceded neurodegeneration, indicating an active role of microglia in this process. Altered gene pathways overlapped with those typical of PD. Our observations indicate that α-syn inclusion formation is not the major driver in the early phases of PD-like neurodegeneration, but that microglia, activated by diffusible, oligomeric α-syn, may play a key role in this process. Our findings uncover new features of α-syn induced pathologies, in particular microgliosis, and point to the necessity for a broader view of the process of α-syn spreading.


Assuntos
Doença de Parkinson , alfa-Sinucleína/metabolismo , Animais , Modelos Animais de Doenças , Camundongos , Microglia/metabolismo , Doenças Neuroinflamatórias , Doença de Parkinson/genética , alfa-Sinucleína/genética
2.
Urol Int ; 106(10): 1061-1067, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34130302

RESUMO

INTRODUCTION: The impact of teratomatous elements in orchiectomy specimens of metastasized testicular germ cell tumors (TGCT) regarding oncological outcome is still unclear. METHODS: We performed a retrospective analysis including 146 patients with metastasized TGCT analysing patient characteristics. RESULTS: Twenty-six (18%) of all patients showed teratomatous elements in the orchiectomy specimens. TGCT with teratomatous elements showed a significantly higher frequency of clinical-stage 2C-3 disease (73 vs. 49%, p = 0.031), visceral metastases (58 vs. 32%, p = 0.015), and poor prognosis (p = 0.011) than TGCT without teratomatous elements. Teratoma-containing TGCT revealed a significantly higher rate of post-chemotherapy retroperitoneal lymph node dissection (PC-RPLND, 54 vs. 32%, p = 0.041), with teratomatous elements being more often present in the PC-RPLND specimens (43 vs. 11%, p = 0.020) than nonteratoma-containing primaries. In the Kaplan-Meier estimates, the presence of teratomatous elements in orchiectomy specimens was associated with a significantly reduced relapse-free survival (RFS) (p = 0.049) during a median follow-up of 36 months (10-115.5). CONCLUSIONS: The presence of teratomatous elements in orchiectomy specimens is associated with an advanced tumor stage, worse treatment response as well as a reduced RFS in metastasized TGCT. Consequently, the presence of teratomatous elements might act as a reliable stratification tool for treatment decision in TGCT patients.


Assuntos
Neoplasias Embrionárias de Células Germinativas , Teratoma , Neoplasias Testiculares , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Orquiectomia , Espaço Retroperitoneal , Estudos Retrospectivos , Teratoma/cirurgia , Neoplasias Testiculares/patologia
3.
Invest New Drugs ; 39(4): 914-927, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33492639

RESUMO

Introduction Differentiation therapy is a promising strategy for cancer treatment. The translationally controlled tumor protein (TCTP) is an encouraging target in this context. By now, this field of research is still at its infancy, which motivated us to perform a large-scale screening for the identification of novel ligands of TCTP. We studied the binding mode and the effect of TCTP blockade on the cell cycle in different cancer cell lines. Methods Based on the ZINC-database, we performed virtual screening of 2,556,750 compounds to analyze the binding of small molecules to TCTP. The in silico results were confirmed by microscale thermophoresis. The effect of the new ligand molecules was investigated on cancer cell survival, flow cytometric cell cycle analysis and protein expression by Western blotting and co-immunoprecipitation in MOLT-4, MDA-MB-231, SK-OV-3 and MCF-7 cells. Results Large-scale virtual screening by PyRx combined with molecular docking by AutoDock4 revealed five candidate compounds. By microscale thermophoresis, ZINC10157406 (6-(4-fluorophenyl)-2-[(8-methoxy-4-methyl-2-quinazolinyl)amino]-4(3H)-pyrimidinone) was identified as TCTP ligand with a KD of 0.87 ± 0.38. ZINC10157406 revealed growth inhibitory effects and caused G0/G1 cell cycle arrest in MOLT-4, SK-OV-3 and MCF-7 cells. ZINC10157406 (2 × IC50) downregulated TCTP expression by 86.70 ± 0.44% and upregulated p53 expression by 177.60 ± 12.46%. We validated ZINC10157406 binding to the p53 interaction site of TCTP and replacing p53 by co-immunoprecipitation. Discussion ZINC10157406 was identified as potent ligand of TCTP by in silico and in vitro methods. The compound bound to TCTP with a considerably higher affinity compared to artesunate as known TCTP inhibitor. We were able to demonstrate the effect of TCTP blockade at the p53 binding site, i.e. expression of TCTP decreased, whereas p53 expression increased. This effect was accompanied by a dose-dependent decrease of CDK2, CDK4, CDK, cyclin D1 and cyclin D3 causing a G0/G1 cell cycle arrest in MOLT-4, SK-OV-3 and MCF-7 cells. Our findings are supposed to stimulate further research on TCTP-specific small molecules for differentiation therapy in oncology.


Assuntos
Antineoplásicos/farmacologia , Drogas em Investigação/farmacologia , Neoplasias/tratamento farmacológico , Proteína Tumoral 1 Controlada por Tradução/antagonistas & inibidores , Antineoplásicos/administração & dosagem , Artesunato/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Simulação por Computador , Bases de Dados de Produtos Farmacêuticos , Relação Dose-Resposta a Droga , Drogas em Investigação/administração & dosagem , Humanos , Ligantes , Simulação de Acoplamento Molecular , Neoplasias/patologia , Proteína Tumoral 1 Controlada por Tradução/metabolismo
4.
J Vasc Interv Radiol ; 30(9): 1452-1458, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31371137

RESUMO

PURPOSE: To evaluate the radiation dose in patients undergoing prostatic artery embolization (PAE) using cone-beam CT and 3-dimensional (3D) guidance software. MATERIALS AND METHODS: In this single-center retrospective study, 100 patients with benign prostatic hyperplasia (mean prostate volume, 83.6 mL ± 44.2; 69.4 ± 9.6 years of age; body mass index, 26.5 ± 4.2) were treated using PAE between October 2016 and April 2018. Informed consent was obtained from all participants included in the study. All patients received at least 1 intraprocedural cone-beam CT per side for evaluation of the vessel anatomy and software rendering of 3D guidance for catheter guidance. Digital subtraction angiography (DSA) was performed in the distal branches only. The total dose area product (DAP), along with the DAP attributed to fluoroscopy, DSA, and cone-beam CT, were assessed. RESULTS: Bilateral embolization was achieved in 83 patients (83%). The average total DAP was 134.4 Gy ⋅ cm2 ± 69.5 (range, 44.7-410.9 Gy ⋅ cm2). Fluoroscopy, DSA, and cone-beam CT accounted for 35.5 Gy ⋅ cm2 ± 21.3 (range, 8.6-148.6 Gy ⋅ cm2) or 26.4% (percentage of total DAP), 58.2 Gy ⋅ cm2 ± 48.3 (range, 10.3-309.3 Gy ⋅ cm2) or 43.3%, and 40.7 Gy ⋅ cm2 ± 14.5 (range, 15.9-86.3 Gy ⋅ cm2) or 30.3%, respectively. Average procedure time was 89.4 ± 27.0 minutes, and the average fluoroscopy time was 30.9 ± 12.2 minutes. CONCLUSIONS: Intraprocedural cone-beam CT in combination with 3D guidance software allows for identification and catheterization of the prostatic artery in PAE. Furthermore, the results of this trial indicate that this study protocol may lead to a low overall radiation dose.


Assuntos
Artérias/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Tomografia Computadorizada de Feixe Cônico , Embolização Terapêutica , Imageamento Tridimensional , Próstata/irrigação sanguínea , Hiperplasia Prostática/terapia , Doses de Radiação , Radiografia Intervencionista/métodos , Software , Idoso , Angiografia por Tomografia Computadorizada/efeitos adversos , Tomografia Computadorizada de Feixe Cônico/efeitos adversos , Embolização Terapêutica/efeitos adversos , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Hiperplasia Prostática/diagnóstico por imagem , Exposição à Radiação , Radiografia Intervencionista/efeitos adversos , Estudos Retrospectivos , Medição de Risco , Fatores de Tempo
5.
J Biol Chem ; 292(10): 4185-4197, 2017 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-28154179

RESUMO

To improve our understanding of properties that confer successful inhibition of chemokines in vivo, we analyzed anti-murine CXCL10 monoclonal antibodies (mAb) having different characteristics. 1B6 displayed potent inhibition of cell recruitment in vitro with an IC50 of 0.5 nm but demonstrated little efficacy in various animal models of human disease. On the contrary, 1F11 showed efficacy in several models of inflammation yet was less potent at inhibiting chemotaxis in vitro with an IC50 of 21 nm Furthermore, we observed that 1B6 displayed a rapid dose-dependent clearance (t½ 10-60 h) in contrast to 1F11, which presented a dose-proportional pharmacokinetic profile and a half-life of 12 days. Moreover, 1B6 recognized glycosaminoglycan (GAG)-bound CXCL10, resulting in target-mediated clearance, which was corroborated using CXCL10-deficient mice. In contrast to 1B6, 1F11 inhibited the interaction of CXCL10 with GAGs, did not recognize GAG-bound CXCL10, and did not display target-mediated drug disposition. Confirming previous animal studies, 1B6 was poor at reversing glycemia in a model of type 1 diabetes, whereas 1F11 induced early and prolonged control of diabetes. Furthermore, when using 1A4, a subsequently generated anti-mCXCL10 mAb that shares the property with 1F11 of being unable to recognize CXCL10 immobilized on GAG, we observed a similar superior control of diabetes as compared with 1B6. We therefore concluded that targeting chemokines with antibodies such as 1B6 that recognize the more abundant GAG-bound form of the chemokine may not be the optimal strategy to achieve disease control.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Quimiocina CXCL10/antagonistas & inibidores , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Endotélio Vascular/metabolismo , Glicosaminoglicanos/metabolismo , Animais , Anticorpos Monoclonais/farmacocinética , Células Cultivadas , Quimiocina CXCL10/imunologia , Quimiocina CXCL10/metabolismo , Quimiotaxia de Leucócito/fisiologia , Cricetinae , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Tecidual
6.
Pharmacol Res ; 129: 262-273, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29179999

RESUMO

Alzheimer's disease (AD) is the most prevalent form of dementia. The exact pathophysiology of this disease remains incompletely understood and safe and effective therapies are required. AD is highly correlated with neuroinflammation and oxidative stress in brain causing neuronal loss. Nuclear factor of activated B-cells (NF-κB) is involved in physiological inflammatory processes and thus representing a promising target for inflammation-based AD therapy. Phytochemicals are able to interfere with the NF-κB pathway. They inhibit the phosphorylation or the ubiquitination of signaling molecules, and thus, inhibit the degradation of IκB. The translocation of NF-κB to the nucleus and subsequent transcription of pro-inflammatory cytokines are inhibited by the actions of phytochemicals. Additionally, natural compounds preventing the interaction of NF-κB can block NF-κB's transcriptional activity by inhibiting its binding to target DNA. Many polyphenols including curcumin, resveratrol, pterostilbene, punicalagin, macranthoin G, salidroside, 4-O-methylhonokiol, lycopene, genistein, obovatol and gallic acid were reported as potent NF-κB inhibitors for AD treatment. Several alkaloids such as galantamine, glaucocalyxin B, tetrandrine, berberine, oridonin, anatabine have been shown anti-inflammatory effects in AD models in vitro as well as in vivo. Besides, vitamins, tanshinone IIA, artemisinin, dihydroasparagusic acid, geniposide, xanthoceraside, l-theranine, 1,8-cineole and paeoniflorin were described as promising NF-κB inhibitors. In conclusion, natural products from plants represent interesting candidates for AD treatment. They may qualify as promising compounds for the development of derivatives providing enhanced pharmacological features.


Assuntos
Alcaloides/farmacologia , Doença de Alzheimer/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Compostos Fitoquímicos/farmacologia , Polifenóis/farmacologia , Animais , Humanos , Vitaminas/farmacologia
7.
Mol Ther ; 25(2): 523-533, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28153099

RESUMO

CD47 is a ubiquitously expressed immune checkpoint receptor that is often upregulated in cancer. CD47 interacts with its counter-receptor SIRPα on macrophages and other myeloid cells to inhibit cancer cell phagocytosis and drive immune evasion. To overcome tolerability and "antigen sink" issues arising from widespread CD47 expression, we generated dual-targeting bispecific antibodies that selectively block the CD47-SIRPα interaction on malignant cells expressing a specific tumor-associated antigen; e.g., CD19 or mesothelin. These bispecific κλ bodies are fully human, native IgG1 molecules, combining tumor targeting and selective CD47 blockade with immune activating mechanisms mediated by the Fc portion of the antibody. CD47-neutralizing κλ bodies efficiently kill cancer cells in vitro and in vivo but interact only weakly with healthy cells expressing physiological levels of CD47. Accordingly, a κλ body administered to non-human primates showed a typical IgG pharmacokinetic profile and was well tolerated. Importantly, κλ bodies preserve their tumoricidal capabilities in the presence of a CD47 antigen sink. Thus, dual-targeting κλ bodies allow for efficacious yet safe targeting of CD47 in cancer. Such a bispecific design could be applied to limit the extent of neutralization of other ubiquitously expressed therapeutic targets.


Assuntos
Anticorpos Biespecíficos/farmacologia , Antígeno CD47/metabolismo , Animais , Anticorpos Biespecíficos/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antígenos de Neoplasias/imunologia , Antineoplásicos/farmacologia , Antígeno CD47/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Mesotelina , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/metabolismo , Fagocitose/imunologia , Ligação Proteica/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Phytother Res ; 32(2): 185-198, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29044858

RESUMO

Medicinal plants have always had great value for the human population due to their valuable constituents and potential bioactivities. The objective of this review is to present an updated overview of an important medicinal plant genus Nepeta L., from the family Lamiaceae, revealing its traditional utilization, biological activity, phytoconstituents, and mechanisms of action. For this purpose, a literature survey was carried out by using SciFinder, ScienceDirect, Scopus, PubMed, and Web of Science followed by a revision of the bibliographies of the related articles. We have described and analyzed the role of plants in drug discovery and the importance of Nepeta species. Information on the utilization purposes of Nepeta species in folk medicine has been emphasized, and scientific studies on the biological effects and secondary metabolites are addressed. Nepeta species are characterized by terpenoid-type compounds and phenolic constituents, which exert several activities such as an antimicrobial, repellent against major pathogen vector mosquitoes, insecticide, larvicide against Anopheles stephensi, cytotoxic anticarcinogen, antioxidant, anticonvulsant, analgesic, anti-inflammatory agent, and antidepressant, revealing its importance in medicinal and agricultural fields. On the basis of numerous studies, the Nepeta genus demonstrates remarkable therapeutic effects against various diseases. However, clinical studies are warranted to confirm preclinical findings.


Assuntos
Medicina Tradicional/métodos , Nepeta/química , Fitoterapia/métodos , Plantas Medicinais/efeitos dos fármacos , Humanos
9.
PLoS Pathog ; 11(11): e1005276, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26587982

RESUMO

Arenaviruses such as Lassa virus (LASV) can cause severe hemorrhagic fever in humans. As a major impediment to vaccine development, delayed and weak neutralizing antibody (nAb) responses represent a unifying characteristic of both natural infection and all vaccine candidates tested to date. To investigate the mechanisms underlying arenavirus nAb evasion we engineered several arenavirus envelope-chimeric viruses and glycan-deficient variants thereof. We performed neutralization tests with sera from experimentally infected mice and from LASV-convalescent human patients. NAb response kinetics in mice correlated inversely with the N-linked glycan density in the arenavirus envelope protein's globular head. Additionally and most intriguingly, infection with fully glycosylated viruses elicited antibodies, which neutralized predominantly their glycan-deficient variants, both in mice and humans. Binding studies with monoclonal antibodies indicated that envelope glycans reduced nAb on-rate, occupancy and thereby counteracted virus neutralization. In infected mice, the envelope glycan shield promoted protracted viral infection by preventing its timely elimination by the ensuing antibody response. Thus, arenavirus envelope glycosylation impairs the protective efficacy rather than the induction of nAbs, and thereby prevents efficient antibody-mediated virus control. This immune evasion mechanism imposes limitations on antibody-based vaccination and convalescent serum therapy.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Arenavirus/imunologia , Febres Hemorrágicas Virais/imunologia , Polissacarídeos/imunologia , Animais , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Humanos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular
10.
Arch Toxicol ; 90(10): 2497-511, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27325308

RESUMO

Primary human hepatocytes (PHH) are still considered as gold standard for investigation of in vitro metabolism and hepatotoxicity in pharmaceutical research. It has been shown that the three-dimensional (3D) cultivation of PHH in a sandwich configuration between two layers of extracellular matrix (ECM) enables the hepatocytes to adhere three dimensionally leading to formation of in vivo like cell-cell contacts and cell-matrix interactions. The aim of the present study was to investigate the influence of different ECM compositions on morphology, cellular arrangement and bile canaliculi formation as well as bile excretion processes in PHH sandwich cultures systematically. Freshly isolated PHH were cultured for 6 days between two ECM layers made of collagen and/or Matrigel in four different combinations. The cultures were investigated by phase contrast microscopy and immunofluorescence analysis with respect to cell-cell connections, repolarization as well as bile canaliculi formation. The influence of the ECM composition on cell activity and viability was measured using the XTT assay and a fluorescent dead or alive assay. Finally, the bile canalicular transport was analyzed by live cell imaging to monitor the secretion and accumulation of the fluorescent substance CDF in bile canaliculi. Using collagen and Matrigel in different compositions in sandwich cultures of hepatocytes, we observed differences in morphology, cellular arrangement and cell activity of PHH in dependence of the ECM composition. Sandwich-cultured hepatocytes with an underlay of collagen seem to represent the best in vivo tissue architecture in terms of formation of trabecular cell arrangement. Cultures overlaid with collagen were characterized by the formation of abundant bile canaliculi, while the bile canaliculi network in hepatocytes cultured on a layer of Matrigel and overlaid with collagen showed the most branched and stable canalicular network. All cultures showed a time-dependent leakage of CDF from the bile canaliculi into the culture supernatant with variations in dependence on the used matrix combination. In conclusion, the results of this study show that the choice of ECM has an impact on the morphology, cell assembly and bile canaliculi formation in PHH sandwich cultures. The morphology and the multicellular arrangement were essentially influenced by the underlaying matrix, while bile excretion and leakage of sandwich-cultured hepatocytes were mainly influenced by the overlay matrix. Leaking and damaged bile canaliculi could be a limitation of the investigated sandwich culture models in long-term excretion studies.


Assuntos
Canalículos Biliares/metabolismo , Bile/metabolismo , Matriz Extracelular/metabolismo , Hepatócitos/metabolismo , Cultura Primária de Células/métodos , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Adesão Celular , Polaridade Celular , Sobrevivência Celular , Células Cultivadas , Colágeno/química , Combinação de Medicamentos , Feminino , Hepatócitos/citologia , Humanos , Laminina/química , Masculino , Microscopia de Contraste de Fase , Pessoa de Meia-Idade , Proteoglicanas/química
11.
Biochim Biophys Acta ; 1843(12): 2913-25, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25229427

RESUMO

Deoxyribose-phosphate aldolase (EC 4.1.2.4), which converts 2-deoxy-d-ribose-5-phosphate into glyceraldehyde-3-phosphate and acetaldehyde, belongs to the core metabolism of living organisms. It was previously shown that human cells harbor deoxyribose phosphate aldolase activity but the protein responsible of this activity has never been formally identified. This study provides the first experimental evidence that DERA, which is mainly expressed in lung, liver and colon, is the human deoxyribose phosphate aldolase. Among human cell lines, the highest DERA mRNA level and deoxyribose phosphate aldolase activity were observed in liver-derived Huh-7 cells. DERA was shown to interact with the known stress granule component YBX1 and to be recruited to stress granules after oxidative or mitochondrial stress. In addition, cells in which DERA expression was down-regulated using shRNA formed fewer stress granules and were more prone to apoptosis after clotrimazole stress, suggesting the importance of DERA for stress granule formation. Furthermore, the expression of DERA was shown to permit cells in which mitochondrial ATP production was abolished to make use of extracellular deoxyinosine to maintain ATP levels. This study unraveled a previously undescribed pathway which may allow cells with high deoxyribose-phosphate aldolase activity, such as liver cells, to minimize or delay stress-induced damage by producing energy through deoxynucleoside degradation.

12.
Methods ; 60(1): 99-110, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23500657

RESUMO

The use of next generation sequencing (NGS) for the analysis of antibody sequences both in phage display libraries and during in vitro selection processes has become increasingly popular in the last few years. Here, our methods developed for DNA preparation, sequencing and data analysis are presented. A key parameter has also been to develop new software designed for high throughput antibody sequence analysis that is used in combination with publicly available tools. As an example of our methods, we provide data from the extensive analysis of five scFv libraries generated using different heavy chain CDR3 diversification strategies. The results not only confirm that the library designs were correct but also reveal differences in quality not easily identified by standard DNA sequencing approaches. The very large number of reads permits extensive sequence coverage after the selection process. Furthermore, as samples can be multiplexed, costs decrease and more information is gained per NGS run. Using examples of results obtained post phage display selections against two antigens, frequency and clustering analysis identified novel antibody fragments that were then shown to be specific for the target antigen. In summary, the methods described here demonstrate how NGS analysis enhances quality control of complex antibody libraries as well as facilitates the antibody discovery process.


Assuntos
Anticorpos/química , Bacteriófagos/genética , Descoberta de Drogas , Sequenciamento de Nucleotídeos em Larga Escala , Biblioteca de Peptídeos
13.
MAbs ; 16(1): 2362432, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38849989

RESUMO

In contrast to natural antibodies that rely mainly on the heavy chain to establish contacts with their cognate antigen, we have developed a bispecific antibody format in which the light chain (LC) drives antigen binding and specificity. To better understand epitope-paratope interactions in this context, we determined the X-ray crystallographic structures of an antigen binding fragment (Fab) in complex with human CD47 and another Fab in complex with human PD-L1. These Fabs contain a κ-LC and a λ-LC, respectively, which are paired with an identical heavy chain (HC). The structural analysis of these complexes revealed the dominant contribution of the LCs to antigen binding, but also that the common HC provides some contacts in both CD47 and PD-L1 Fab complexes. The anti-CD47 Fab was affinity optimized by diversifying complementary-determining regions of the LC followed by phage display selections. Using homology modeling, the contributions of the amino acid modification to the affinity increase were analyzed. Our results demonstrate that, despite a less prominent role in natural antibodies, the LC can mediate high affinity binding to different antigens and neutralize their biological function. Importantly, Fabs containing a common variable heavy (VH) domain enable the generation of bispecific antibodies retaining a truly native structure, maximizing their therapeutic potential.


Assuntos
Anticorpos Biespecíficos , Antígeno B7-H1 , Antígeno CD47 , Fragmentos Fab das Imunoglobulinas , Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/imunologia , Humanos , Antígeno CD47/imunologia , Antígeno CD47/química , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/imunologia , Antígeno B7-H1/imunologia , Antígeno B7-H1/química , Antígeno B7-H1/antagonistas & inibidores , Cristalografia por Raios X , Cadeias Leves de Imunoglobulina/química , Cadeias Leves de Imunoglobulina/imunologia , Modelos Moleculares
14.
J Biol Chem ; 287(2): 1458-67, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22041899

RESUMO

Dual-specific antibodies are characterized by an antigen-combining site mediating specific interactions with two different antigens. We have generated five dual-specific single chain variable fragments (scFv) that neutralize the activity of the two chemokines, CXCL9 and CXCL10, to bind to their receptor CXCR3. To better understand how these dual-specific scFvs bind these two chemokines that only share a 37% sequence identity, we mapped their epitopes on human CXCL9 and CXCL10 and identified serine 13 (Ser(13)) as a critical residue. It is conserved between the two chemokines but not in the third ligand for CXCR3, CXCL11. Furthermore, Ser(13) is exposed in the tetrameric structure of CXCL10, which is consistent with our finding that the scFvs are able to bind to CXCL9 and CXCL10 immobilized on glycosaminoglycans. Overall, the data indicate that these dual-specific scFvs bind to a conserved surface involved in CXCR3 receptor interaction for CXCL10 and CXCL9. Thus, structural mimicry between the two targets is likely to be responsible for the observed dual specificity of these antibody fragments.


Assuntos
Especificidade de Anticorpos , Quimiocina CXCL10/química , Quimiocina CXCL9/química , Mimetismo Molecular , Anticorpos de Cadeia Única/química , Animais , Quimiocina CXCL10/genética , Quimiocina CXCL10/imunologia , Quimiocina CXCL11/química , Quimiocina CXCL11/genética , Quimiocina CXCL11/imunologia , Quimiocina CXCL9/genética , Quimiocina CXCL9/imunologia , Humanos , Macaca fascicularis , Macaca mulatta , Camundongos , Coelhos , Receptores CXCR3/química , Receptores CXCR3/genética , Receptores CXCR3/imunologia , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia
15.
Eur Heart J ; 33(15): 1964-74, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21606075

RESUMO

AIMS: The chemokine CCL5 plays a critical role as neutrophil and macrophage activator do in atherosclerosis and myocardial infarction. Thus, we investigated whether the treatment with a neutralizing monoclonal antibody (mAb) to mouse CCL5 would provide therapeutic benefit when provoking a coronary-associated ischaemic event. METHODS AND RESULTS: C57Bl/6 mice were submitted to left coronary artery permanent ligature. Then, various parameters were monitored for up to 21 days. At5 min and 3 days after coronary occlusion, mice received one intravenous injection of the rat anti-mouse CCL5 mAb or isotype IgG control. Infarct size was assessed histologically and by measuring serum cardiac troponin I levels. Kinetics of CCL5 tissue expression, leucocyte infiltration, matrix metalloproteinase (MMP) levels, and collagen deposition were histologically assessed. Serum chemokine levels were measured by enzyme-linked immunosorbent assay. Cardiac function and dimensions were assessed by magnetic resonance imaging (MRI). Chronic ischaemia increased both circulating and intracardiac levels of CCL5. At 24 h, treatment with the anti-CCL5 mAb resulted in a smaller infarct size and reduced circulating levels of chemokines. This effect was associated with reduction of neutrophil and macrophage infiltration within the infarcted myocardium. After 3 days of chronic ischaemia, anti-CCL5 mAb treatment reduced cardiac MMP-9. At 7 days, collagen content was significantly lower. At 21 days, neutralizing CCL5 improved mouse survival, cardiac myocyte size, and cardiac function. CONCLUSION: Treatment with anti-CCL5 mAb significantly reduced both infarct size and post-infarction heart failure in a mouse model of chronic cardiac ischaemia. Cardioprotective effects were associated with the reduction of leucocyte recruitment within infarcted hearts.


Assuntos
Anticorpos Monoclonais/farmacologia , Quimiocina CCL5/fisiologia , Insuficiência Cardíaca/patologia , Infarto do Miocárdio/patologia , Animais , Peso Corporal/fisiologia , Quimiocina CCL5/antagonistas & inibidores , Quimiocina CCL5/imunologia , Quimiotaxia de Leucócito/fisiologia , Doença Crônica , Colágeno/metabolismo , Ligadura , Macrófagos/fisiologia , Metaloproteinase 8 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/fisiologia , Isquemia Miocárdica/metabolismo , Reperfusão Miocárdica/métodos , Infiltração de Neutrófilos/fisiologia , Neutrófilos/fisiologia , Tamanho do Órgão/fisiologia , Taxa de Sobrevida
16.
Anticancer Res ; 43(6): 2741-2747, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37247924

RESUMO

BACKGROUND/AIM: The robotic retroperitoneal approach for renal mass surgery was introduced in 2018 at the Department of Urology in the clinic of Leverkusen, Germany. Clinical criteria for the choice of the access site (trans- vs. retroperitoneal) are not clearly defined. The aim of this study was to explore the learning curve and the impact of the access site on clinical outcome, in order to elucidate which preoperative clinical criteria should be taken into account when choosing the renal approach site. PATIENTS AND METHODS: This retrospective study included 107 patients who underwent robotic tumor surgery between June 2018 and March 2022 at the Department of Urology in the Clinic of Leverkusen, Germany. Data from 86 patients with transperitoneal robotic surgery of the kidney and 21 patients with retroperitoneal access were available for analysis. We evaluated the data of patients in a trans- and a retroperitoneal access group. The preoperative clinical data included anthropomorphic data, the Body Mass Index (BMI) as well as the Preoperative Aspects and Dimensions Used for Anatomical Classification of Renal Masses (PADUA) - score. Intraoperative and postoperative data such as blood loss, clamping time, renal function and the learning curve of the surgeons was used to evaluate the outcomes of the two groups. RESULTS: Operation time in the retroperitoneal group was significantly shorter (p=0.015). Operation-specific variables showed no significant difference between the two groups. PADUA score and hilar clamping time showed no difference (p=0.345 and p=0.130, respectively). The learning curve in the retroperitoneal access group unveiled a noticeable difference in the experience and mastery of the involved surgeons. CONCLUSION: Mastery of the retroperitoneal approach is readily possible for surgeons with previous experience in robotic renal surgery without compromising the operative morbidity. The PADUA-score seems most suitable as a preoperative clinical criterion for choosing the renal approach site.


Assuntos
Neoplasias Renais , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Estudos Retrospectivos , Curva de Aprendizado , Resultado do Tratamento , Nefrectomia/métodos , Espaço Retroperitoneal/cirurgia , Espaço Retroperitoneal/patologia , Laparoscopia/métodos
17.
Biochem Biophys Res Commun ; 417(1): 29-34, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22133680

RESUMO

BACKGROUND: We investigated the role of the programmed cell death 4 (PDCD4) tumor suppressor gene in specimens of transitional cell carcinoma and of healthy individuals. METHODS: PDCD4 immunohistochemical expression was investigated in 294 cases in histologically proven transitional cell carcinoma in different tumorous stages (28 controls, 122 non-muscle invasive urothelial carcinoma, stages Tis-T1, 119 invasive transitional cell carcinoma stages T2-T4 and 25 metastases). MiR-21 expression, an important PDCD4 regulator, was assessed with real-time PCR analysis and showed inverse correlation to tissue PDCD4 expression. RESULTS: Nuclear and cytoplasmatic PDCD4 immunostaining decreased significantly with histopathological progression of the tumor (p<0001). Controls showed strong nuclear and cytoplasmatic immunohistochemical staining. MiR-21 up regulation in tissue corresponded to PDCD4 suppression. CONCLUSIONS: These data support a decisive role for PDCD4 down regulation in transitional cell carcinoma and confirm miR-21 as a negative regulator for PDCD4. Additionally, PDCD4 immunohistochemical staining turns out to be a possible diagnostic marker for transitional cell carcinoma.


Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Carcinoma de Células de Transição/metabolismo , MicroRNAs/biossíntese , Proteínas de Ligação a RNA/biossíntese , Neoplasias Urológicas/metabolismo , Urotélio/metabolismo , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias Urológicas/patologia , Urotélio/patologia
18.
J Immunol ; 185(4): 2544-54, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20644170

RESUMO

Chemokines are key regulators of leukocyte trafficking and play a crucial role under homeostatic and inflammatory conditions. Because chemokines are involved in multiple pathologies, they represent an attractive class of therapeutic targets. However, because of the redundancy of this system, neutralizing a single chemokine may be insufficient to achieve therapeutic benefit. Our strategy was to use a Fc-fusion recombinant protein form of the poxvirus-derived viral CC chemokine inhibitor protein (vCCI-Fc) that has the ability to specifically bind to multiple CC chemokines and neutralize their activity. In this study, we demonstrate first that, in vivo, vCCI-Fc prevents CC chemokine-dependent migration of macrophages into inflamed tissue of carageenan-challenged mice. We next studied this effect of inhibiting CC chemokine activity in a model more relevant to human disease, collagen-induced arthritis. Mice receiving vCCI-Fc revealed a striking retention of splenocytes, including activated and IFN-gamma-secreting CD4(+) and CD8(+) T cells, that was associated with a concomitant decrease of cells in the draining lymph nodes. These phenomena resulted in a significant decrease in the incidence of disease and a reduction in clinical score, joint inflammation, and cartilage destruction as compared with mice receiving isotype control. Taken together, these results define a role for CC chemokines in the control of disease, as interfering with their function leads to a previously unappreciated role of controlling inflammatory cell trafficking in and out of secondary lymphoid organs.


Assuntos
Artrite Experimental/imunologia , Quimiocinas CC/imunologia , Inflamação/imunologia , Proteínas Recombinantes de Fusão/imunologia , Animais , Artrite Experimental/prevenção & controle , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Quimiocinas CC/antagonistas & inibidores , Quimiocinas CC/metabolismo , Feminino , Citometria de Fluxo , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/metabolismo , Inflamação/prevenção & controle , Interferon gama/imunologia , Interferon gama/metabolismo , Contagem de Linfócitos , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Ligação Proteica , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Baço/citologia , Baço/imunologia , Baço/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Vaccinia virus/genética , Vaccinia virus/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
19.
J Clin Med ; 11(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36078994

RESUMO

BACKGROUND: Hybrid imaging with prostate-specific membrane antigen (PSMA) is gaining importance as an increasingly meaningful tool for prostate cancer (PC) diagnostics and as a guide for therapy decisions. This study aims to investigate and compare the performance of [18F]PSMA-1007 (18F-PSMA) and [68Ga]Ga-PSMA-11 positron emission tomography/computed tomography (68Ga-PSMA) in the initial staging of PC patients. METHODS: The data of 88 biopsy-proven patients were retrospectively evaluated. PSMA-avid lesions were compared with the histopathologic Gleason Score (GS) for prostate biopsies, and the results were plotted by receiver operating characteristic (ROC)-curve. Optimal maximum standardized uptake value (SUVmax) cut-off values were rated using the Youden index. RESULTS: 18F-PSMA was able to distinguish GS ≤ 7a from ≥7b with a sensitivity of 62%, specificity of 85%, positive predictive value (PPV) of 92%, and accuracy of 67% for a SUVmax of 8.95, whereas sensitivity was 54%, specificity 91%, PPV 93%, and accuracy 66% for 68Ga-PSMA (SUVmax 8.7). CONCLUSIONS: Both methods demonstrated a high concordance of detected PSMA-avid lesions with histopathologically proven PC. 18F-PSMA and 68Ga-PSMA are both suitable for the characterization of primary PC with a comparable correlation of PSMA-avid lesions with GS. Neither method showed a superior advantage. Our calculated SUVmax thresholds may represent valuable parameters in clinical use to distinguish clinically significant PC (csPC) from non-csPC.

20.
Cancers (Basel) ; 14(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35326629

RESUMO

This study aimed to compare the diagnostic performance of [18F]PSMA-1007 positron emission tomography/computed tomography (PET/CT) (18F-PSMA) and [68Ga]Ga-PSMA-11 PET/CT (68Ga-PSMA) by identifying prostate-specific antigen (PSA) threshold levels for optimal detecting recurrent prostate cancer (PC) and to compare both methods. Retrospectively, the study included 264 patients. The performances of 18F-PSMA and 68Ga-PSMA in relation to the pre-scan PSA were assessed by receiver operating characteristic (ROC) curve. 18F-PSMA showed PC-lesions in 87.5% (112/128 patients), while 68Ga-PSMA identified them in 88.9% (121/136). For 18F-PSMA biochemical recurrent (BCR) patients treated with radical prostatectomy (78/128, patient group: F-RP), a PSA of 1.08 ng/mL was found to be the optimal cut-off level for predicting positive and negative scans (AUC = 0.821; 95%, CI: 0.710−0.932), while for prostatectomized 68Ga-PSMA BCR-patients (89/136, patient group: Ga-RP), the cut-off was 1.84 ng/mL (AUC = 0.588; 95%, CI: 0.410−0.766). In patients with PSA < 1.08 ng/mL (F-RP) 76.3% and <1.84 ng/mL (Ga-RP) 78.6% scans were positive, whereas patients with PSA ≥ 1.08 ng/mL (F-RP) or 1.84 ng/mL (Ga-RP) had positive scan results in 100% and 91.5% (p < 0.001/p = 0.085). The identified PSA thresholds for PSMA-mappable PC lesions in BCR-patients (RP) showed a better separation for 18F-PSMA with regard to the distinguishing of positive and negative PC-lesions compared to 68Ga-PSMA. However, the two PSMA PET/CT tracers gave similar overall findings.

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