scholarly journals 43 kDa Glycoprotein (gp43) from Paracoccidioides brasiliensis Induced IL-17A and PGE2 Production by Human Polymorphonuclear Neutrophils: Involvement of TLR2 and TLR4

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Taiane Priscila Gardizani ◽  
Amanda Manoel Della Coletta ◽  
Graziela Gorete Romagnoli ◽  
Rosana Puccia ◽  
Ana Paula Moreira Serezani ◽  
...  

The glycoprotein gp43 is the major antigenic/diagnostic component of Paracoccidioides brasiliensis, one of the etiologic agents of paracoccidioidomycosis (PCM). Gp43 has protective roles in mice, but due to adhesive properties, this glycoprotein has also been associated with immune evasion mechanisms. The present study evaluated gp43 interaction in vitro with Toll-like receptors 2 and 4 (TLR2 and TLR4) present in polymorphonuclear neutrophils (PMNs) from healthy human individuals and the consequent modulation of the immune response through the expression and release of cytokines and eicosanoids. PMNs were incubated in the absence or presence of monoclonal antibodies anti-TLR2 and anti-TLR4 (individually or in combination) before gp43 stimulation. Then, PMNs were analyzed for the expression of both surface receptors and the detection of intracytoplasmic IL-17A and IL-4 using flow cytometry, while the production of PGE2, LTB4, IL-6, IL-10, IL-12, IFN-γ, and TNF-α was evaluated in the supernatants by enzyme-linked immunosorbent assay (ELISA). Our results showed that gp43 increased TLR2 and TLR4 expression by PMNs and induced PGE2 and IL-17A via TLR4 and TLR2, respectively. Thus, our data suggest that gp43 from P. brasiliensis might modulate host susceptibility to the fungal infection by affecting PGE2 and IL-17A production.

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1245 ◽  
Author(s):  
Vanessa D’Antongiovanni ◽  
Laura Benvenuti ◽  
Matteo Fornai ◽  
Carolina Pellegrini ◽  
Renè van den Wijngaard ◽  
...  

The role played by adenosine A2B receptors (A2BRs) in the regulation of enteric glial cell (EGC) functions remains unclear. This study was aimed at investigating the involvement of A2BRs in the control of EGC functions in a model of obesity. C57BL/6 mice were fed with standard diet (SD) or high fat diet (HFD) for eight weeks. Colonic tachykininergic contractions were recorded in the presence of BAY60-6583 (A2BRs agonist), MRS1754 (A2BRs antagonist), and the gliotoxin fluorocitrate. Immunofluorescence distribution of HuC/D, S100β, and A2BRs was assessed in whole mount preparations of colonic myenteric plexus. To mimic HFD, EGCs were incubated in vitro with palmitate (PA) and lipopolysaccharide (LPS), in the absence or in the presence of A2BR ligands. Toll-like receptor 4 (TLR4) expression was assessed by Western blot analysis. Interleukin-1β (IL-1β), substance P (SP), and glial cell derived neurotrophic factor (GDNF) release were determined by enzyme-linked immunosorbent assay (ELISA) assays. MRS1754 enhanced electrically evoked tachykininergic contractions of colonic preparations from HFD mice. BAY60-6583 decreased the evoked tachykininergic contractions, with higher efficacy in HFD mice. Such effects were blunted upon incubation with fluorocitrate. In in vitro experiments on EGCs, PA and LPS increased TLR4 expression as well as IL-1β, GDNF, and SP release. Incubation with BAY60-6583 reduced TLR4 expression as well as IL-1β, GDNF, and SP release. Such effects were blunted by MRS1754. The present results suggest that A2BRs, expressed on EGCs, participate in the modulation of enteric inflammation and altered tachykininergic responses associated with obesity, thus representing a potential therapeutic target.


2019 ◽  
Vol 63 (6) ◽  
Author(s):  
Frederic Ries ◽  
Astrid Alflen ◽  
Pamela Aranda Lopez ◽  
Hendrik Beckert ◽  
Matthias Theobald ◽  
...  

ABSTRACTThere is a growing body of evidence for immunomodulatory side effects of antifungal agents on different immune cells, e.g., T cells. Therefore, the aim of our study was to clarify these interactions with regard to the effector functions of polymorphonuclear neutrophils (PMN). Human PMN were preincubated with fluconazole (FLC), voriconazole (VRC), posaconazole (POS), isavuconazole (ISA), caspofungin (CAS), micafungin (MFG), conventional amphotericin B (AMB), and liposomal amphotericin B (LAMB). PMN then were analyzed by flow cytometry for activation, degranulation, and phagocytosis and by dichlorofluorescein assay to detect reactive oxygen species (ROS). Additionally, interleukin-8 (IL-8) release was measured by enzyme-linked immunosorbent assay. POS led to enhanced activation, degranulation, and generation of ROS, whereas IL-8 release was reduced. In contrast, ISA-pretreated PMN showed decreased activation signaling, impaired degranulation, and lower generation of ROS. MFG caused enhanced expression of activation markers but impaired degranulation, phagocytosis, generation of ROS, and IL-8 release. CAS showed increased phagocytosis, whereas degranulation and generation of ROS were reduced. AMB led to activation of almost all effector functions besides impaired phagocytosis, whereas LAMB did not alter any effector functions. Independent from class, antifungal agents show variable influence on neutrophil effector functionsin vitro. Whether this is clinically relevant needs to be clarified.


2011 ◽  
Vol 18 (10) ◽  
pp. 1680-1688 ◽  
Author(s):  
Martha E. Urán ◽  
Joshua D. Nosanchuk ◽  
Angela Restrepo ◽  
Andrew J. Hamilton ◽  
Beatriz L. Gómez ◽  
...  

ABSTRACTSeveral cell wall constituents, including melanins or melanin-like compounds, have been implicated in the pathogenesis of a wide variety of microbial diseases caused by diverse species of pathogenic bacteria, fungi, and helminthes. Among these microorganisms, the dimorphic fungal pathogenParacoccidioides brasiliensisproduces melanin in its conidial and yeast forms. In the present study, melanin particles fromP. brasiliensiswere injected into BALB/c mice in order to produce monoclonal antibodies (MAbs). We identified five immunoglobulin G1 (IgG1) κ-chain and four IgM melanin-binding MAbs. The five IgG1 κ-chain isotypes are the first melanin-binding IgG MAbs ever reported. The nine MAbs labeledP. brasiliensisconidia and yeast cells bothin vitroand in pulmonary tissues. The MAbs cross-reacted with melanin-like purified particles from other fungi and also with commercial melanins, such as synthetic andSepia officinalismelanin. Melanization during paracoccidioidomycosis (PCM) was also further supported by the detection of IgG antibodies reactive to melanin fromP. brasiliensisconidia and yeast in sera and bronchoalveolar lavage fluids fromP. brasiliensis-infected mice, as well as in sera from human patients with PCM. Serum specimens from patients with other mycoses were also tested for melanin-binding antibodies by enzyme-linked immunosorbent assay, and cross-reactivities were detected for melanin particles from different fungal sources. These results suggest that melanin fromP. brasiliensisis an immunologically active fungal structure that activates a strong IgG humoral response in humans and mice.


Author(s):  
Yohan Ricci Zonta ◽  
Ana Laura Ortega Dezen ◽  
Amanda Manoel Della Coletta ◽  
Kaio Shu Tsyr Yu ◽  
Larissa Carvalho ◽  
...  

Paracoccidioidomycosis is a systemic fungal disease, considered endemic in Latin America. Its etiological agents, fungi of the Paracoccidioides complex, have restricted geographic habitat, conidia as infecting form, and thermo-dimorphic characteristics. Polymorphonuclear neutrophils (PMNs) are responsible for an important defense response against fungus, releasing Neutrophil Extracellular Traps (NETs), which can wrap and destroy the yeasts. However, it has been described that some pathogens are able to evade from these DNA structures by releasing DNase as an escape mechanism. As different NETs patterns have been identified in PMNs cultures challenged with different isolates of Paracoccidioides brasiliensis, the general objective of this study was to identify if different patterns of NETs released by human PMNs challenged with Pb18 (virulent) and Pb265 (avirulent) isolates would be correlated with fungal ability to produce a DNase-like protein. To this end, PMNs from healthy subjects were isolated and challenged in vitro with both fungal isolates. The production, release, and conformation of NETs in response to the fungi were evaluated by Confocal Microscopy, Scanning Microscopy, and NETs Quantification. The identification of fungal DNase production was assessed by DNase TEST Agar, and the relative gene expression for hypothetical proteins was investigated by RT-qPCR, whose genes had been identified in the fungal genome in the GenBank (PADG_11161 and PADG_08285). It was possible to verify the NETs release by PMNs, showing different NETs formation when in contact with different isolates of the fungus. The Pb18 isolate induced the release of looser, larger, and more looking like degraded NETs compared to the Pb265 isolate, which induced the release of denser and more compact NETs. DNase TEST Agar identified the production of a DNase-like protein, showing that only Pb18 showed the capacity to degrade DNA in these plates. Besides that, we were able to identify that both PADG_08528 and PADG_11161 genes were more expressed during interaction with neutrophil by the virulent isolate, being PADG_08528 highly expressed in these cultures, demonstrating that this gene could have a greater contribution to the production of the protein. Thus, we identified that the virulent isolate is inducing more scattered and loose NETs, probably by releasing a DNase-like protein. This factor could be an important escape mechanism used by the fungus to escape the NETs action.


2015 ◽  
Vol 20 (6) ◽  
pp. 768-778 ◽  
Author(s):  
Karunya Srinivasan ◽  
Sucharita Roy ◽  
Nathaniel Washburn ◽  
Sandra F. Sipsey ◽  
Robin Meccariello ◽  
...  

Fidelity of glycan structures is a key requirement for biotherapeutics, with carbohydrates playing an important role for therapeutic efficacy. Comprehensive glycan profiling techniques such as liquid chromatography (LC) and mass spectrometry (MS), while providing detailed description of glycan structures, require glycan cleavage, labeling, and paradigms to deconvolute the considerable data sets they generate. On the other hand, lectins as probes on microarrays have recently been used in orthogonal approaches for in situ glycoprofiling but require analyte labeling to take advantage of the capabilities of automated microarray readers and data analysis they afford. Herein, we describe a lectin-based microtiter assay (lectin–enzyme-linked immunosorbent assay [ELISA]) to quantify terminal glycan moieties, applicable to in vitro and in-cell glycan-engineered Fc proteins as well as intact IgGs from intravenous immunoglobulin (IVIG), a blood product containing pooled polyvalent IgG antibodies extracted from plasma from healthy human donors. We corroborate our findings with industry-standard LC-MS profiling. This “customizable” ELISA juxtaposes readouts from multiple lectins, focusing on a subset of glycoforms, and provides the ability to discern single- versus dual-arm glycosylation while defining levels of epitopes at sensitivities comparable to MS. Extendable to other biologics, this ELISA can be used stand-alone or complementary to MS for quantitative glycan analysis.


Author(s):  
Bhikshapathi D. V. R. N. ◽  
Arun Kumar Jarathi ◽  
Suresh Gande ◽  
Viswaja Medipally ◽  
Ramesh Bomma

Background and the purpose of the study: Risedronate sodium inhibits osteoclast bone resorption and modulates bone metabolism. Risedronate has a high affinity for hydroxyapatite crystals in bone and is a potent antiresorptive agent. In the present investigation efforts were made to improve the bioavailability of risedronate sodium by increasing the residence time of the drug through sustained-release matrix capsule formulation via gastroretentive mechanism. Capsules were prepared by wet granulation technique. The influence of gel forming agents, amount of risedronate and total weight of capsules on physical properties, in vitro buoyancy, drug release, FTIR, DSC, X-ray studies were investigated. The release mechanisms were explored and explained by applying zero order, first order, Higuchi and Korsmeyer equations. The selected formulations were subjected to stability study at 40 °C/75% RH, 25 °C/60% RH for the period of three months. For all formulations, kinetics of drug release from capsules followed Higuchi’s square root of time kinetic treatment heralding diffusion as predominant mechanism of drug release. Formulation containing 25 mg HPMC K4M and 75 mg HPMC K100 LV (F-8) showed zero order release profile. There was no significant change in the selected formulation, when subjected to accelerated stability conditions over a period of three months. X-ray imaging in six healthy human volunteers revealed a mean gastric retention period of 5.60 ± 0.77 hrs for the selected formulation. Stable, sustained release effervescent floating capsules of risedronate sodium could be prepared by wet granulation technique.  


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hiroaki Kanzaki ◽  
Tetsuhiro Chiba ◽  
Junjie Ao ◽  
Keisuke Koroki ◽  
Kengo Kanayama ◽  
...  

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.


Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 437
Author(s):  
Dean Gilham ◽  
Audrey L. Smith ◽  
Li Fu ◽  
Dalia Y. Moore ◽  
Abenaya Muralidharan ◽  
...  

Effective therapeutics are urgently needed to counter infection and improve outcomes for patients suffering from COVID-19 and to combat this pandemic. Manipulation of epigenetic machinery to influence viral infectivity of host cells is a relatively unexplored area. The bromodomain and extraterminal (BET) family of epigenetic readers have been reported to modulate SARS-CoV-2 infection. Herein, we demonstrate apabetalone, the most clinical advanced BET inhibitor, downregulates expression of cell surface receptors involved in SARS-CoV-2 entry, including angiotensin-converting enzyme 2 (ACE2) and dipeptidyl-peptidase 4 (DPP4 or CD26) in SARS-CoV-2 permissive cells. Moreover, we show that apabetalone inhibits SARS-CoV-2 infection in vitro to levels comparable to those of antiviral agents. Taken together, our study supports further evaluation of apabetalone to treat COVID-19, either alone or in combination with emerging therapeutics.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Débora Ferreira ◽  
Joaquim Barbosa ◽  
Diana A. Sousa ◽  
Cátia Silva ◽  
Luís D. R. Melo ◽  
...  

AbstractTriple-negative breast cancer is the most aggressive subtype of invasive breast cancer with a poor prognosis and no approved targeted therapy. Hence, the identification of new and specific ligands is essential to develop novel targeted therapies. In this study, we aimed to identify new aptamers that bind to highly metastatic breast cancer MDA-MB-231 cells using the cell-SELEX technology aided by high throughput sequencing. After 8 cycles of selection, the aptamer pool was sequenced and the 25 most frequent sequences were aligned for homology within their variable core region, plotted according to their free energy and the key nucleotides possibly involved in the target binding site were analyzed. Two aptamer candidates, Apt1 and Apt2, binding specifically to the target cells with $$K_{d}$$ K d values of 44.3 ± 13.3 nM and 17.7 ± 2.7 nM, respectively, were further validated. The binding analysis clearly showed their specificity to MDA-MB-231 cells and suggested the targeting of cell surface receptors. Additionally, Apt2 revealed no toxicity in vitro and showed potential translational application due to its affinity to breast cancer tissue sections. Overall, the results suggest that Apt2 is a promising candidate to be used in triple-negative breast cancer treatment and/or diagnosis.


2021 ◽  
Vol 22 (4) ◽  
pp. 2141
Author(s):  
Srinu Tumpara ◽  
Elena Korenbaum ◽  
Mark Kühnel ◽  
Danny Jonigk ◽  
Beata Olejnicka ◽  
...  

The C-terminal-fragments of alpha1-antitrypsin (AAT) have been identified and their diverse biological roles have been reported in vitro and in vivo. These findings prompted us to develop a monoclonal antibody that specifically recognizes C-36 peptide (corresponding to residues 359–394) resulting from the protease-associated cleavage of AAT. The C-36-targeting mouse monoclonal Immunoglobulin M (IgM) antibody (containing κ light chains, clone C42) was generated and enzyme-linked immunosorbent assay (ELISA)-tested by Davids Biotechnologie GmbH, Germany. Here, we addressed the effectiveness of the novel C42 antibody in different immunoassay formats, such as dot- and Western blotting, confocal laser microscopy, and flow cytometry. According to the dot-blot results, our novel C42 antibody detects the C-36 peptide at a range of 0.1–0.05 µg and shows no cross-reactivity with native, polymerized, or oxidized forms of full-length AAT, the AAT-elastase complex mixture, as well as with shorter C-terminal fragments of AAT. However, the C42 antibody does not detect denatured peptide in SDS-PAGE/Western blotting assays. On the other hand, our C42 antibody, unconjugated as well as conjugated to DyLight488 fluorophore, when applied for immunofluorescence microscopy and flow cytometry assays, specifically detected the C-36 peptide in human blood cells. Altogether, we demonstrate that our novel C42 antibody successfully recognizes the C-36 peptide of AAT in a number of immunoassays and has potential to become an important tool in AAT-related studies.


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