39 research outputs found
Modulation of apoplast proteome by downy mildew in susceptible and tolerant grapevine cultivars
info:eu-repo/semantics/publishedVersio
Human and companion animal proteus mirabilis sharing
Research Areas: MicrobiologyProteus mirabilis is an important pathogen that is associated with urinary tract infections. This study aims to determine the colonization and sharing of P. mirabilis between healthy companion animals and humans that are living together and to evaluate the clonal relatedness of the fecal and clinical stains. Eighteen households (24 humans, 18 dogs, 8 cats) with at least one human–animal pair were studied. Fecal samples were plated onto MacConkey and Hektoen agar and P. mirabilis PFGE analysis (NotI; Dice/UPGMA; 1.5% tolerance) was conducted for the households with multiple positive participants. Antimicrobial-resistance was tested according to CLSI. The fecal P. mirabilis pulse-types were compared with uropathogenic clinical strains (n = 183). Forty-nine P. mirabilis were isolated from eight households. The percentage of colonization in the dogs (44.4%, n = 8/18) was significantly higher (p = 0.0329) than in the humans (12.5%, n = 3/24). Three households had multiple colonized participants. One human–dog pair shared related P. mirabilis strains, which clustered with a clinical strain of animal origin (82.5%). One fecal P. mirabilis strain, from a dog, clustered with two human community-acquired clinical strains (80.9%, 88.9%). To our knowledge, this is the first report of dogs and humans living in close contact and sharing related P. mirabilis strains. The high frequency of colonization in the dogs underlines their possible role as P. mirabilis reservoirs for humans and other dogs.info:eu-repo/semantics/publishedVersio
Proteomic signatures uncover the early key players on Vitis vinifera cv. “Regent - Plasmopara viticola crosstalk
info:eu-repo/semantics/publishedVersio
Therapeutic Potential of Deflamin against Colorectal Cancer Development and Progression
Matrix metalloproteinases (MMPs) are proteolytic enzymes that play a crucial role in
tumor microenvironment remodeling, contributing to inflammatory and angiogenic processes, and
ultimately promoting tumor maintenance and progression. Several studies on bioactive polypeptides
isolated from legumes have shown anti-migratory, anti-MMPs, and anti-tumor effects, potentially
constituting novel strategies for both the prevention and progression of cancer. In this work, we inves-
tigated the anti-tumor role of deflamin, a protein oligomer isolated from white lupine seeds (Lupinus
albus) reported to inhibit MMP-9 and cell migration in colorectal cancer (CRC) cell lines. We found
that deflamin exerts an inhibitory effect on tumor growth and metastasis formation, contributing to
increased tumor apoptosis in the xenotransplanted zebrafish larvae model. Furthermore, deflamin
resulted not only in a significant reduction in MMP-2 and MMP-9 activity but also in impaired cancer
cell migration and invasion in vitro. Using the xenograft zebrafish model, we observed that deflamin
inhibits collagen degradation and angiogenesis in the tumor microenvironment in vivo. Overall, our
work reveals the potential of deflamin as an agent against CRC development and progression.info:eu-repo/semantics/publishedVersio
Highly specific blood-brain barrier transmigrating single-domain antibodies selected by an In Vivo phage display screening
Research Areas: Pharmacology & PharmacyA major bottleneck in the successful development of central nervous system (CNS) drugs
is the discovery and design of molecules that can cross the blood-brain barrier (BBB). Nano-delivery
strategies are a promising approach that take advantage of natural portals of entry into the brain
such as monoclonal antibodies (mAbs) targeting endogenous BBB receptors. However, the main
selected mAbs rely on targeting broadly expressed receptors, such as the transferrin and insulin
receptors, and in selection processes that do not fully mimic the native receptor conformation, leading
to mistargeting and a low fraction of the administered dose effectively reaching the brain. Thus, there
is an urgent need to identify new BBB receptors and explore novel antibody selection approaches that
can allow a more selective delivery into the brain. Considering that in vitro models fail to completely
mimic brain structure complexity, we explored an in vivo cell immunization approach to construct a
rabbit derived single-domain antibody (sdAb) library towards BBB endothelial cell receptors. The
sdAb antibody library was used in an in vivo phage display screening as a functional selection of
novel BBB targeting antibodies. Following three rounds of selections, next generation sequencing
analysis, in vitro brain endothelial barrier (BEB) model screenings and in vivo biodistribution studies,
five potential sdAbs were identified, three of which reaching >0.6% ID/g in the brain. To validate the
brain drug delivery proof-of-concept, the most promising sdAb, namely RG3, was conjugated at the
surface of liposomes encapsulated with a model drug, the pan-histone deacetylase inhibitor panobinostat (PAN). The translocation efficiency and activity of the conjugate liposome was determined in
a dual functional in vitro BEB-glioblastoma model. The RG3 conjugated PAN liposomes enabled an
efficient BEB translocation and presented a potent antitumoral activity against LN229 glioblastoma cells without influencing BEB integrity. In conclusion, our in vivo screening approach allowed the selection of highly specific nano-antibody scaffolds with promising properties for brain targeting and drug delivery.info:eu-repo/semantics/publishedVersio
An apoplastic fluid extraction method for the characterization of grapevine leaves proteome and metabolome from a single sample
The analysis of complex biological systems keeps challenging
researchers. The main goal of systems biology is to decipher interactions
within cells, by integrating datasets from large scale analytical
approaches including transcriptomics, proteomics and metabolomics
andmore specialized ‘OMICS’ such as epigenomics and lipidomics. Studying
different cellular compartments allows a broader understanding of cell
dynamics. Plant apoplast, the cellular compartment external to the plasma
membrane including the cell wall, is particularly demanding to analyze.
Despite our knowledge on apoplast involvement on several processes from
cell growth to stress responses, its dynamics is still poorly known due to the
lack of efficient extraction processes adequate to each plant system.Analyzing
woody plants such as grapevine raises even more challenges. Grapevine is
among the most important fruit crops worldwide and awider characterization
of its apoplast is essential for a deeper understanding of its physiology and cellular
mechanisms. Here, we describe, for the first time, a vacuum-infiltrationcentrifugationmethod
that allows a simultaneous extraction of grapevine apoplastic
proteins and metabolites from leaves on a single sample, compatible
with high-throughput mass spectrometry analyses. The extracted apoplast
from two grapevine cultivars, Vitis vinifera cv ‘Trincadeira’ and ‘Regent’, was
directly used for proteomics and metabolomics analysis. The proteome was
analyzed by nanoLC-MS/MS and more than 700 common proteinswere identified,
with highly diverse biological functions. The metabolome profile
through FT-ICR-MS allowed the identification of 514 unique putative compounds
revealing a broad spectrum of molecular classesinfo:eu-repo/semantics/publishedVersio
Rabbit derived VL single-domains as promising scaffolds to generate antibody–drug conjugates
© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Antibody-drug conjugates (ADCs) are among the fastest-growing classes of therapeutics in oncology. Although ADCs are in the spotlight, they still present significant engineering challenges. Therefore, there is an urgent need to develop more stable and effective ADCs. Most rabbit light chains have an extra disulfide bridge, that links the variable and constant domains, between Cys80 and Cys171, which is not found in the human or mouse. Thus, to develop a new generation of ADCs, we explored the potential of rabbit-derived VL-single-domain antibody scaffolds (sdAbs) to selectively conjugate a payload to Cys80. Hence, a rabbit sdAb library directed towards canine non-Hodgkin lymphoma (cNHL) was subjected to in vitro and in vivo phage display. This allowed the identification of several highly specific VL-sdAbs, including C5, which specifically target cNHL cells in vitro and present promising in vivo tumor uptake. C5 was selected for SN-38 site-selective payload conjugation through its exposed free Cys80 to generate a stable and homogenous C5-DAB-SN-38. C5-DAB-SN-38 exhibited potent cytotoxicity activity against cNHL cells while inhibiting DNA-TopoI activity. Overall, our strategy validates a platform to develop a novel class of ADCs that combines the benefits of rabbit VL-sdAb scaffolds and the canine lymphoma model as a powerful framework for clinically translation of novel therapeutics for cancer.This work was supported by the Portuguese Funding Agency, Fundação para a Ciência e Tecnologia, FCT IP (SAICT/2017/32085, PTDC/QUI-OUT/3989/2021 and Ph.D. fellowship SFRH/BD/131468/2017 to ASA and SFRH/BD/90514/2012 to JD). CIISA has provided support through Project UIDB/00276/2020, funded by FCT and LA/P/0059/2020-AL4AnimalS. Research Institute for Medicines (iMed.ULisboa) acknowledges the financial support of Fundação para a Ciência e Tecnologia (Projects: PTDC/QUI-OUT/3989/2021; UIDB/04138/2020 and UIDP/04138/2020). The NMR spectrometers are part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project Nº 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC).info:eu-repo/semantics/publishedVersio
RegaDB: Community-driven data management and analysis for infectious diseases
Summary: RegaDB is a free and open source data management and analysis environment for infectious diseases. RegaDB allows clinicians to store, manage and analyse patient data, including viral genetic sequences. Moreover, RegaDB pr
Detection of human neutrophil elastase (HNE) on wound dressings as marker of inflammation
Chronic wound fluids have elevated concentration of human neutrophil elastase (HNE) which can be used as inflammation/infection marker. Our goal is to develop functional materials for fast diagnosis of wound inflammation/infection by using HNE as a specific marker. For that, fluorogenic peptides with a HNE-specific cleavage sequence were incorporated into traditional textile dressings, to allow real-time detection of the wound status. Two different fluorogenic approaches were studied in terms of intensity of the signal generated upon HNE addition: a fluorophore 7-amino-4-trifluormethylcoumarin (AFC) conjugated to a HNE-specific peptide and two fluorophore/quencher pairs (FAM/Dabcyl and EDANS/Dabcyl) coupled to a similar peptide as a Förster resonance energy transfer (FRET) strategy. Also, two immobilization methods were tested: sonochemistry immobilization onto a cotton bandage and glutaraldehyde (GTA)-assisted chemical crosslinking onto a polyamide dressing. The immobilized fluorogenic AFC peptide showed an intense fluorescence emission in the presence of HNE. HNE also induced an enhanced fluorescent signal with the EDANS/Dabcyl FRET peptide which showed to be a more sensitive and effective strategy than the AFC peptide. However, its chemical immobilization onto the polyamide dressing greatly decreased its detection, mainly due to the more difficult access of the enzyme to the cleavage sequence of the immobilized peptide. After optimization of the in situ immobilization, it will be possible to use these fluorescence-functionalized dressings for an effective and specific monitoring of chronic wounds by simply using a portable ultraviolet (UV) light source. We envision that the development of this point-of-care medical device for wound control will have a great impact on patients life quality and reduction of costs on health care system.This study was funded by the European project InFact-Functional materials for fast diagnosis of wound infection (FP7-NMP-2013-SME-7-grant agreement no. 604278). The work done at Centre of Biological Engineering (CEB) was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte 2020-Programa Operacional Regional do Norte
Large-scale screening of unknown varieties in a grapevine intra-varietal variability collection
Since the last decade of the last century, it is known that many old grapevine varieties are descendants of other varieties through natural crossing. Portugal has an important program for the conservation of representative samples of intra-varietal variability of all autochthonous varieties, managed by the Portuguese Association for Grapevine Diversity (PORVID), which makes looking for genotypes with dubious identification an important activity from a perspective of its valorisation. This communication presents the results of the molecular analysis of 5,000 samples (accessions) from the PORVID’s collection, using nine microsatellite loci currently recommended by the International Organization of Vine and Wine (OIV) for genetic grapevine identification. The results obtained confirmed the molecular identity of 4,220 samples corresponding to 214 varieties present in the official list of Portuguese varieties. In 780 samples, 95 profiles with a plural number of accessions revealed not to be listed in the Vitis International Variety Catalogue (VIVC) database, corresponding to possible varieties either descendent from natural crossing from at least one known parental variety, or from undetermined origin. Furthermore, the need for a comprehensive strategy aimed at uncovering other hidden varieties is discussed to prevent their imminent loss, deepen understanding of their origin, and add economic value and sustainability to the vine and wine sector