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1.
Cancers (Basel) ; 16(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38791940

RESUMO

PURPOSE: To investigate the molecular characteristics of and potential for precision medicine in KRAS wildtype pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS: We investigated 27 patients with KRASWT PDAC at our institution. Clinical data were obtained via chart review. Tumor specimens for each subject were interrogated for somatic single nucleotide variants, insertion and deletions, and copy number variants by DNA sequencing. Gene fusions were detected from RNA-seq. A patient-derived organoid (PDO) was developed from a patient with a MET translocation and expanded ex vivo to predict therapeutic sensitivity prior to enrollment in a phase 2 clinical trial. RESULTS: Transcriptomic analysis showed our cohort may be stratified by the relative gene expression of the KRAS signaling cascade. The PDO derived from our patient harboring a TFG-MET rearrangement was found to have in vitro sensitivity to the multi-tyrosine kinase inhibitor crizotinib. The patient was enrolled in the phase 2 SPARTA clinical trial and received monotherapy with vebrelitinib, a c-MET inhibitor, and achieved a partial and durable response. CONCLUSIONS: KRASWT PDAC is molecularly distinct from KRASMUT and enriched with potentially actionable genetic variants. In our study, transcriptomic profiling revealed that the KRAS signaling cascade may play a key role in KRASWT PDAC. Our report of a KRASWT PDAC patient with TFG-MET rearrangement who responded to a cMET inhibitor further supports the pursuit of precision oncology in this sub-population. Identification of targetable mutations, perhaps through approaches like RNA-seq, can help enable precision-driven approaches to select optimal treatment based on tumor characteristics.

2.
Parasite Immunol ; 46(2): e13025, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38372623

RESUMO

Trichomonas vaginalis (Tv) is a parasite that causes trichomoniasis, a prevalent sexually-transmitted infection. Neutrophils are found at the site of infection, and can rapidly kill the parasite in vitro, using trogocytosis. However, the specific molecular players in neutrophil killing of Tv are unknown. Here, we show that complement proteins play a role in Tv killing by human neutrophil-like cells (NLCs). Using CRISPR/Cas9, we generated NLCs deficient in each of three complement receptors (CRs) known to be expressed on human neutrophils: CR1, CR3, and CR4. Using in vitro trogocytosis assays, we found that CR3, but not CR1 or CR4 is required for maximum trogocytosis of the parasite by NLCs, with NLCs lacking CR3 demonstrating ~40% reduction in trogocytosis, on average. We also observed a reduction in NLC killing of Tv in CR3 knockout, but not CR1 or CR4 knockout NLCs. On average, NLCs lacking CR3 had ~50% reduction in killing activity. We also used a parallel approach of pre-incubating NLCs with blocking antibodies against CR3, which similarly reduced NLC killing of parasites. These data support a model in which Tv is opsonized by the complement protein iC3b, and bound by neutrophil CR3 receptor, to facilitate trogocytic killing of the parasite.


Assuntos
Parasitos , Trichomonas vaginalis , Humanos , Animais , Antígeno de Macrófago 1 , Trichomonas vaginalis/genética , Neutrófilos , Antígeno CD11b
3.
BMC Urol ; 24(1): 43, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368330

RESUMO

Peritoneal loose body (PLB) is a kind of lesions located in the abdominal cavity or pelvic cavity, which is rare and difficult to diagnose. The diameter of PLB is mostly 0.5-2.5 cm. Most PLBS are asymptomatic. Here we reported a case of giant PLB in the pelvis and analyzed its structure and protein composition. Surgical exploration revealed a white oval mass (4.5*4*3 cm) in the pelvic cavity. After the mass was removed, the symptoms of hematuria disappeared and the patient was discharged on the second postoperative day. Histochemical staining showed that PLB was mainly composed of collagen and scattered calcification. The protein components of PLB were detected by proteome analysis, and a variety of proteins related to collagen deposition and calcification were identified in PLB.


Assuntos
Calcinose , Laparoscopia , Doenças Peritoneais , Humanos , Doenças Peritoneais/diagnóstico , Doenças Peritoneais/cirurgia , Doenças Peritoneais/patologia , Peritônio/patologia , Tomografia Computadorizada por Raios X , Colágeno
4.
Mol Genet Genomics ; 299(1): 20, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424265

RESUMO

To understand the lifespan of higher organisms, including humans, it is important to understand lifespan at the cellular level as a prerequisite. So, fission yeast is a good model organism for the study of lifespan. To identify the novel factors involved in longevity, we are conducting a large-scale screening of long-lived mutant strains that extend chronological lifespan (cell survival in the stationary phase) using fission yeast. One of the newly acquired long-lived mutant strains (No.98 mutant) was selected for analysis and found that the long-lived phenotype was due to a missense mutation (92Phe → Ile) in the plb1+ gene. plb1+ gene in fission yeast is a nonessential gene encoding a homolog of phospholipase B, but its functions under normal growth conditions, as well as phospholipase B activity, remain unresolved. Our analysis of the No.98 mutant revealed that the plb1 mutation reduces the integrity of the cellular membrane and cell wall and activates Sty1 via phosphorylation.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Humanos , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Longevidade/genética , Lisofosfolipase/genética , Lisofosfolipase/metabolismo , Mutação , Regulação Fúngica da Expressão Gênica
5.
J Cell Sci ; 137(3)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38224139

RESUMO

Neutrophil-directed motility is necessary for host defense, but its dysregulation can also cause collateral tissue damage. Actinopathies are monogenic disorders that affect the actin cytoskeleton and lead to immune dysregulation. Deficiency in ARPC1B, a component of the Arp2/3 complex, results in vascular neutrophilic inflammation; however, the mechanism remains unclear. Here, we generated human induced pluripotent stem cell (iPSC)-derived neutrophils (denoted iNeutrophils) that are deficient in ARPC1B and show impaired migration and a switch from forming pseudopodia to forming elongated filopodia. We show, using a blood vessel on a chip model, that primary human neutrophils have impaired movement across an endothelium deficient in APRC1B. We also show that the combined deficiency of ARPC1B in iNeutrophils and endothelium results in further reduction in neutrophil migration. Taken together, these results suggest that ARPC1B in endothelium is sufficient to drive neutrophil behavior. Furthermore, the findings provide support for using the iPSC system to understand human neutrophil biology and model disease in a genetically tractable system.


Assuntos
Complexo 2-3 de Proteínas Relacionadas à Actina , Células-Tronco Pluripotentes Induzidas , Neutrófilos , Humanos , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Movimento Celular , Proteínas do Citoesqueleto , Células Endoteliais , Endotélio
6.
Clin Ter ; 174(6): 525-530, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38048116

RESUMO

Objectives: Surgical repair of severely injured posterior cruciate ligament is mandatory. Therefore, the anatomical features of the PCL and its two bundles description help to define the appropriate size of the allograft for excellent results in reconstruction surgeries. Material and methods: Fifty knees were dissected from twenty-five fresh human cadavers (15 male and 10 female) of donors used for teaching purpose. The length and footprint area of PCL and patellar tendon length were measured, and determined the range of normality according to sex and height. Results: The average lengths of the PCL's Antero-medial (AM) and posterolateral (PL) bundle were 35. 52 ± 0.66 mm and 32.76 ± 0.64mm, respectively in male and 35.37 ± 0.07 & 32.58 ± 0.61mm in female. The femoral footprint of PCL was 133.10 ± 0.7 mm2 in male and 133.05 ± 0.7 mm2 in female observed, while the tibial footprint 132.21± 1.02 mm2 in male and 132.42 ± 0.8 mm2 in female was observed. Conclusion: The AM and PL bundle lengths were higher in males than females. There was a strong correlation between height and length of ligaments but no correlation with age.


Assuntos
Procedimentos de Cirurgia Plástica , Ligamento Cruzado Posterior , Feminino , Masculino , Humanos , Articulação do Joelho , Cadáver , Doadores de Tecidos
7.
Quant Imaging Med Surg ; 13(12): 7789-7801, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38106300

RESUMO

Background: As lung cancer is one of the most significant factors seriously endangering human health, a robot-assisted puncture system with high accuracy and safety is urgently needed. The purpose of this investigation was to compare the safety and effectiveness of such a robot-assisted system to the conventional computed tomography (CT)-guided manual method for percutaneous lung biopsies (PLBs) in pigs. Methods: An optical navigation robot-assisted puncture system was developed and compared to the traditional CT-guided PLB using simulated lesions in experimental animals. A total of 30 pulmonary nodules were successfully created in 5 pigs (Wuzhishan pig, 1 male and 4 females). Of these, 15 were punctured by the optical navigation robot-assisted puncture system (robotic group), and 15 were manually punctured under CT guidance (manual group). The biopsy success rate, operation time, first needle tip-target point deviation, and needle adjustment times were compared between groups. Postoperative CT scans were performed to identify complications. Results: The single puncture success rate was higher in the robotic group (13/15; 86.7%) than in the manual group (8/15; 53.3%). The first puncture was closer to the target lesion (1.8±1.7 mm), and the operation time was shorter (7.1±3.7 minutes) in the robotic group than in the manual group (4.4±2.8 mm and 12.9±7.6 minutes, respectively). The angle deviation was smaller in the robotic group (3.26°±2.48°) than in the manual group (7.71°±3.86°). The robotic group displayed significant advantages (P<0.05). The primary complication in both groups was slight bleeding, with an incidence of 26.7% in the robotic group and 40.0% in the manual group. There was 1 case of pneumothorax in the manual group, and there were no deaths due to complications in either group. Conclusions: An optical navigation robot-assisted system for PLBs guided by CT images was developed and demonstrated. The experimental results indicate that the proposed system is accurate, efficient, and safe in pigs.

9.
Arch Razi Inst ; 78(1): 475-483, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-37312689

RESUMO

Candida tropical has been found as the most abundant pathogenic yeast species under the group Candida-non-albicans. Despite this, it is taxonomically related to C. albicans and has many of its pathogenic characteristics. Infection with Candida tropicalis is closely associated with many virulence factors encoded by multiple virulence genes. This study aims to diagnose C. tropicalis based on the presence of 18SrRNA and to detect many virulence genes. C. tropicalis isolates were collected from oral candidiasis patients. Children infected with oral thrush ranging in age from infants to 12 years old provided 150 samples. C. albicans (66.68 %), C. tropicalis (13.21 %), C. krusie (9.43 %), C. parapsilosis (7.55 %), and C. glarata were isolated as C. tropicalis types, according to the findings of the present study (2.83%). The presence of the 18SrRNA gene was confirmed in the isolates. All isolates were positive for cph1 and hwp1, while some were positive for sap1 (78.5%) and plb1 genes (71.4%). Using sequences and phylogenetic trees, it was determined that there was negligible genetic variation between local isolates and global strains. These virulence factor genes play a crucial role in developing infections.


Assuntos
Candidíase Bucal , Criança , Humanos , Lactente , Candida tropicalis , Candidíase Bucal/diagnóstico , Filogenia , RNA Ribossômico 18S/genética , Virulência , Fatores de Virulência/genética , Pré-Escolar
10.
Biochim Biophys Acta Biomembr ; 1865(7): 184180, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37245861

RESUMO

In phagocytes, superoxide anion (O2-), the precursor of reactive oxygen species, is produced by the NADPH oxidase complex to kill pathogens. Phagocyte NADPH oxidase consists of the transmembrane cytochrome b558 (cyt b558) and four cytosolic components: p40phox, p47phox, p67phox, and Rac1/2. The phagocyte activation by stimuli leads to activation of signal transduction pathways. This is followed by the translocation of cytosolic components to the membrane and their association with cyt b558 to form the active enzyme. To investigate the roles of membrane-interacting domains of the cytosolic proteins in the NADPH oxidase complex assembly and activity, we used giant unilamellar phospholipid vesicles (GUV). We also used the neutrophil-like cell line PLB-985 to investigate these roles under physiological conditions. We confirmed that the isolated proteins must be activated to bind to the membrane. We showed that their membrane binding was strengthened by the presence of the other cytosolic partners, with a key role for p47phox. We also used a fused chimera consisting of p47phox(aa 1-286), p67phox(aa 1-212) and Rac1Q61L, as well as mutated versions in the p47phox PX domain and the Rac polybasic region (PB). We showed that these two domains have a crucial role in the trimera membrane-binding and in the trimera assembly to cyt b558. They also have an impact on O2.- production in vitro and in cellulo: the PX domain strongly binding to GUV made of a mix of polar lipids; and the PB region strongly binding to the plasma membrane of neutrophils and resting PLB-985 cells.


Assuntos
Citocromos b , Fosfolipídeos , Fosfolipídeos/metabolismo , Citocromos b/metabolismo , Fagócitos/metabolismo , NADPH Oxidases/metabolismo , Membrana Celular/metabolismo , Sítios de Ligação
11.
JACC Basic Transl Sci ; 8(1): 1-15, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36777175

RESUMO

Analysis of the spatio-temporal distribution of calcium sparks showed a preferential increase in sparks near the sarcolemma in atrial myocytes from patients with atrial fibrillation (AF), linked to higher ryanodine receptor (RyR2) phosphorylation at s2808 and lower calsequestrin-2 levels. Mathematical modeling, incorporating modulation of RyR2 gating, showed that only the observed combinations of RyR2 phosphorylation and calsequestrin-2 levels can account for the spatio-temporal distribution of sparks in patients with and without AF. Furthermore, we demonstrate that preferential calcium release near the sarcolemma is key to a higher incidence and amplitude of afterdepolarizations in atrial myocytes from patients with AF.

12.
Plants (Basel) ; 11(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36235328

RESUMO

Anoectochilus roxburghii (Wall.) Lindl has been used in Chinese herbal medicine for treating various ailments. However, its wild resources are endangered, and artificial cultivation of the plant is limited by the low regeneration rate of conventional propagation methods. The lack of A. roxburghii resources is detrimental to the commercial production of the plant and kinsenoside, which is unique to Anoectochilus species. To develop highly efficient methods for A. roxburghii micropropagation and find alternative resources for kinsenoside production, we created an induction, proliferation, and regeneration of PLBs (IPR-PLB) protocol for A. roxburghii. We also analyzed the kinsenoside and flavonoid contents during the induction and proliferation of PLBs. The best media of IPR-PLB for PLB induction and proliferation (secondary PLB induction and proliferation), shoot formation, and rooting medium were Murashige and Skoog (MS) + 3 mg/L 6-benzylaminopurine (6-BA) + 0.5 mg/L naphthaleneacetic acid (NAA) + 0.8 mg/L zeatin (ZT) + 0.2 mg/L 2,4-dichlorophenoxyacetic acid (2, 4-D), MS + 3 mg/L 6-BA + 0.5 mg/L NAA, and MS + 0.5 mg/L NAA, respectively. On these optimized media, the PLB induction rate was 89 ± 2.08%, secondary PLB induction rate was 120 ± 5%, secondary PLB proliferation rate was 400 ± 10% and 350 ± 10 % in terms of the quantity and biomass at approximately 1 month, shoot induction rate was 10.5 shoots/PLB mass, and root induction rate was 98%. All plantlets survived after acclimation. Darkness or weak light were essential for PLB proliferation, and light was crucial for PLB differentiation on these optimized media. The kinsenoside contents of PLBs and secondary PLBs were 10.38 ± 0.08 and 12.30 ± 0.08 mg/g fresh weight (FW), respectively. Moreover, the peak kinsenoside content during the proliferation of secondary PLBs was 34.27 ± 0.79 mg/g FW, which was slightly lower than that of the whole plant (38.68 ± 3.12 mg/g FW). Two flavonoids exhibited tissue- or temporal-specific accumulation patterns, and astragalin accumulated exclusively during the first 2 weeks of cultivation. The IPR-PLB protocol for A. roxburghii may facilitate the efficient micropropagation of A. roxburghii plants. Furthermore, the PLBs are a good alternative resource for kinsenoside production.

13.
Cell Commun Signal ; 20(1): 143, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104752

RESUMO

Spatiotemporal regulation of subcellular protein kinase A (PKA) activity for precise substrate phosphorylation is essential for cellular responses to hormonal stimulation. Ryanodine receptor 2 (RyR2) and (sarco)endoplasmic reticulum calcium ATPase 2a (SERCA2a) represent two critical targets of ß adrenoceptor (ßAR) signaling on the sarcoplasmic reticulum membrane for cardiac excitation and contraction coupling. Using novel biosensors, we show that cardiac ß1AR signals to both RyR2 and SERCA2a nanodomains in cardiomyocytes from mice, rats, and rabbits, whereas the ß2AR signaling is restricted from these nanodomains. Phosphodiesterase 4 (PDE4) and PDE3 control the baseline PKA activity and prevent ß2AR signaling from reaching the RyR2 and SERCA2a nanodomains. Moreover, blocking inhibitory G protein allows ß2AR signaling to the RyR2 but not the SERCA2a nanodomains. This study provides evidence for the differential roles of inhibitory G protein and PDEs in controlling the adrenergic subtype signaling at the RyR2 and SERCA2a nanodomains in cardiomyocytes. Video abstract.


Assuntos
Sinalização do Cálcio , Canal de Liberação de Cálcio do Receptor de Rianodina , Animais , Proteínas Quinases Dependentes de AMP Cíclico , Proteínas de Ligação ao GTP , Camundongos , Fosforilação , Coelhos , Ratos , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático
14.
Toxicon X ; 15: 100131, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35769869

RESUMO

The isolation and characterization of individual snake venom components is important for a deeper understanding of the pathophysiology of envenomation and for improving the therapeutic procedures of patients. It also opens possibilities for the discovery of novel toxins that might be useful as tools for understanding cellular and molecular processes. The variable venom composition, toxicological and immunological properties of the common vipers (Vipera berus berus) have been reviewed. The combination of venom gland transcriptomics, bottom-up and top-down proteomics enabled comparison of common viper venom proteomes from multiple individuals. V. b. berus venom contains proteins and peptides belonging to 10-15 toxin families: snake venom metalloproteinase, phospholipases A2 (PLA2), snake venom serine proteinase, aspartic protease, L-amino acid oxidase (LAAO), hyaluronidase, 5'-nucleotidase, glutaminyl-peptide cyclotransferase, disintegrin, C-type lectin (snaclec), nerve growth factor, Kunitz type serine protease inhibitor, snake venom vascular endothelial growth factor, cysteine-rich secretory protein, bradykinin potentiating peptide, natriuretic peptides. PLA2 and LAAO from V. b. berus venom produce more pronounced cytotoxic effects in cancer cells than normal cells, via induction of apoptosis, cell cycle arrest and suppression of proliferation. Proteomic data of V. b. berus venoms from different parts of Russia and Slovakian Republic have been compared with analogous data for Vipera nikolskii venom. Proteomic studies demonstrated quantitative differences in the composition of V. b. berus venom from different geographical regions. Differences in the venom composition of V. berus were mainly driven by the age, sex, habitat and diet of the snakes. The venom variability of V. berus results in a loss of antivenom efficacy against snakebites. The effectiveness of antibodies is discussed. This review presents an overview with a special focus on different toxins that have been isolated and characterized from the venoms of V. b. berus. Their main biochemical properties and toxic actions are described.

15.
J Thorac Dis ; 14(2): 247-256, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35280488

RESUMO

Background: Augmented reality navigation system for percutaneous computed tomography (CT)-guided pulmonary biopsies has recently been introduced. There are no studies in literature about its use for ground glass lesions biopsies. The aim of this study is to evaluate the effectiveness of an augmented reality infrared navigation system performance on CT-guided percutaneous lung ground glass opacity (GGO) biopsy compared to a standard CT-guided technique. Methods: A total of 80 patients with lung GGO who underwent to a percutaneous CT-guided lung biopsy with an augmented reality infrared navigation system were retrospectively enrolled in the study. Comparison was performed with a group of 80 patients who underwent to lung biopsy with the standard CT-guided technique. Evaluation of maximum lesion diameter (MLD), distance between lesion and pleural surface (DPS), distance travelled by the needle (DTP), procedural time, validity of histological sample, procedural complications and the radiation dose to the patient's chest were recorded for each patient of both groups. In addition, each group was divided into two subgroups based on lesion size, according to a cut-off of 1.5 cm (<1.5 cm; ≥1.5 cm). Results: Augmented reality navigation system showed a significant reduction in procedural time, radiation dose administrated to patients and complications rate compared to a standard CT-guided technique. Technical success was achieved in the 100% of cases in both groups, but the diagnostical success was higher in the group where patients underwent to lung biopsies with the use of navigation system. We also found that using an augmented reality navigation system increases the diagnostical success rate for lesion <1.5 cm. MLD, DPS and DTP did not differ significantly between the two groups of patients. Conclusions: The use of an augmented reality navigation system for percutaneous CT-guided pulmonary GGO biopsies has demonstrated a lower incidence of post-procedural complications, a significantly reduction of the radiation dose administered to patients and a higher diagnostical success rate.

16.
JACC Case Rep ; 4(3): 133-136, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35199003

RESUMO

Coronary artery perforation is a rare but serious complication during percutaneous coronary intervention. Distal or small vessel perforation is usually treated by coil, fat, or microsphere embolization. We describe 5 cases of distal coronary perforation that were managed successfully by a novel technique that uses absorbable sutures. (Level of Difficulty: Advanced.).

17.
Rheumatology (Oxford) ; 61(8): 3497-3501, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35171267

RESUMO

OBJECTIVES: JDM is a serious autoimmune and complex genetic disease. Another autoimmune genetic disease, type 1 diabetes (T1D), has been observed for significantly increased prevalence in families with JDM, while increased JDM risk has also been observed in T1D cases. This study aimed to study whether these two autoimmune diseases, JDM and T1D, share common genetic susceptibility. METHODS: From 169 JDM families, 121 unrelated cases with European ancestry (EA) were identified by genome-wide genotyping, principal component analysis and identical-by-descent (IBD) analysis. T1D genetic risk score (GRS) were calculated in these cases and were compared with 361 EA T1D cases and 1943 non-diabetes EA controls. A total of 113 cases of the 121 unrelated European cases were sequenced by whole exome sequencing. RESULTS: We observed increased T1D GRS in JDM cases (P = 9.42E-05). Using whole exome sequencing, we uncovered the T1D genes, phospholipase B1, cystic fibrosis transmembrane conductance regulator, tyrosine hydroxylase, CD6 molecule, perforin 1 and dynein axonemal heavy chain 2, potentially associated with JDM by the burden test of rare functional coding variants. CONCLUSION: Novel mechanisms of JDM related to these T1D genes are suggested by this study, which may imply novel therapeutic targets for JDM and warrant further study.


Assuntos
Doenças Autoimunes , Dermatomiosite , Diabetes Mellitus Tipo 1 , Doenças Autoimunes/genética , Dermatomiosite/genética , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Testes Genéticos , Humanos
18.
Int J Mol Sci ; 23(2)2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35054950

RESUMO

Neutrophils play a very key role in the human immune defense against pathogenic infections. The predominant players in this role during the activation of neutrophils are the release of cytotoxic agents stored in the granules and secretory vesicles and the massive production of reactive oxygen species (ROS) initiated by the enzyme NADPH oxidase. In addition, in living organisms, cells are continuously exposed to endogenous (inflammations, elevated neutrophil presence in the vicinity) and exogenous ROS at low and moderate levels (travels by plane, radiotherapy, space irradiation, blood banking, etc.). To study these effects, we used ROS induced by gamma radiation from low (0.2 Gy) to high (25 Gy) dose levels on PLB-985 cells from a myeloid cell line differentiated to neutrophil-like cells that are considered a good alternative to neutrophils. We determined a much longer lifetime of PLB-985 cells than that of neutrophils, which, as expected, decreased by increasing the irradiation dose. In the absence of any secondary stimulus, a very low production of ROS is detected with no significant difference between irradiated and non-irradiated cells. However, in phagocytosing cells, irradiation doses above 2 Gy enhanced oxidative burst in PLB-985 cells. Whatever the irradiation dose, NADPH oxidase devoid of its cytosolic regulatory units is observed at the plasma membrane in irradiated PLB-985 cells. This result is different from that observed for irradiated neutrophils in which irradiation also induced a translocation of regulatory subunits suggesting that the signal transduction mechanism or pathway operate differently in both cells.


Assuntos
Biomarcadores , Membrana Celular/metabolismo , Citocromos b/metabolismo , Estresse Oxidativo , Fagócitos/metabolismo , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Ativação Enzimática , Raios gama , Humanos , NADPH Oxidases/metabolismo , Neutrófilos/metabolismo , Fagócitos/imunologia , Fagócitos/efeitos da radiação , Transporte Proteico , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória
19.
mSphere ; 7(1): e0094021, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-34986319

RESUMO

Fungal infections remain a major global concern. Emerging fungal pathogens and increasing rates of resistance mean that additional research efforts and resources must be allocated to advancing our understanding of fungal pathogenesis and developing new therapeutic interventions. Neutrophilic granulocytes are a major cell type involved in protection against the important fungal pathogen Aspergillus fumigatus, where they employ numerous defense mechanisms, including production of antimicrobial extracellular vesicles. A major drawback to work with neutrophils is the lack of a suitable cell line system for the study of fungal pathogenesis. To address this problem, we assessed the feasibility of using differentiated PLB-985 neutrophil-like cells as an in vitro model to study A. fumigatus infection. We find that dimethylformamide-differentiated PLB-985 cells provide a useful recapitulation of many aspects of A. fumigatus interactions with primary human polymorphonuclear leukocytes. We show that differentiated PLB-985 cells phagocytose fungal conidia and acidify conidia-containing phagolysosomes similar to primary neutrophils, release neutrophil extracellular traps, and also produce antifungal extracellular vesicles in response to infection. In addition, we provide an improved method for the isolation of extracellular vesicles produced during infection by employing a size exclusion chromatography-based approach. Advanced liquid chromatography-tandem mass spectrometry (LC-MS/MS) proteomics revealed an enrichment of extracellular vesicle marker proteins and a decrease of cytoplasmic proteins in extracellular vesicles isolated using this improved method. Ultimately, we find that differentiated PLB-985 cells can serve as a genetically tractable model to study many aspects of A. fumigatus pathogenesis. IMPORTANCE Polymorphonuclear leukocytes are an important defense against human fungal pathogens, yet our model systems to study this group of cells remain very limited in scope. In this study, we established that differentiated PLB-985 cells can serve as a model to recapitulate several important aspects of human polymorphonuclear leukocyte interactions with the important human fungal pathogen Aspergillus fumigatus. The proposed addition of a cultured neutrophil-like cell line to the experimental toolbox to study fungal pathogenesis will allow for a more mechanistic description of neutrophil antifungal biology. In addition, the easier handling of the cell line compared to primary human neutrophils allowed us to use PLB-985 cells to provide an improved method for isolation of neutrophil-derived extracellular vesicles using size exclusion chromatography. Together, these results provide significant tools and a baseline knowledge for the future study of neutrophil-derived extracellular vesicles in the laboratory.


Assuntos
Aspergillus fumigatus , Neutrófilos , Antifúngicos , Aspergillus fumigatus/fisiologia , Cromatografia Líquida , Humanos , Neutrófilos/microbiologia , Espectrometria de Massas em Tandem
20.
Transl Cancer Res ; 11(12): 4338-4348, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36644169

RESUMO

Background: Pneumothorax (PNX), pulmonary hemorrhage, hemothorax and chest wall hematoma are the most commonly reported complications of percutaneous lung biopsy (PLB). Sealing the biopsy tract with different types of materials is an emerging way to prevent PLB complications. Methods: To investigate the safety and efficacy of a new device, Minimally Invasive Percutaneous Procedure Kit for Pneumothorax (MIPP-Kit PNX), when used in association with a resorbable bio-compatible glue in the prevention of PLB complications. A prospective, multicenter, open-label, single-arm study was performed to evaluate the complication rate after glue administration by the new investigational device during PLBs. Results: Fourty-three patients were enrolled after informed consent signature (40 underwent PLB, while three were screening failures). Only 3 patients (7.5%, 95% CI: 0.0-15.7%) developed complications within 48 h after glue injection during PLB: two developed minor pneumothoraces and one a pulmonary hemorrhage. No patients who showed procedural complications before glue administration were reported with any recurrent or new complications after glue administration. Conclusions: In comparison with the data reported in the literature, this trial results support the safe and effective use of the MIPP kit PNX in the prevention of PLB complications. These promising preliminary results warrant further confirmation in larger clinical trials. Trial Registration: ClinicalTrials.gov identifier: NCT04071509.

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