New insights into interferon-mediated immune responses elicited by Plasmodium liver stage infection. Unravelling the role of Viperin induction

Malaria is a mosquito-borne infectious disease caused by Plasmodium parasites. Despite the efforts being put into the malaria control, the development of efficient therapies has been hindered by the lack of knowledge on the parasite-elicited immune responses. Recent work showed that Plasmodium triggers an innate type I IFN response in the liver, resulting in the induction of interferonstimulated genes (ISGs). Viperin, an antiviral molecule, is one of the most induced ISGs in the host's antiplasmodial response. This thesis aims at characterizing the interferon-mediated immune responses triggered by Plasmodium liver stage infection, providing an integrated view of the potential cellular effectors of intrahepatic parasite control. A time course analysis throughout P. berghei infection revealed that type I and type II interferons-regulated expression of ISGs present two waves of induction coincident with different stages of the parasite's life cycle. A first peak occurs at 42 hours post-infection (hpi) and is followed by a higher peak of induction at 84 hpi, which was identified as potentially being mediated by innate lymphoid cells, whose functionality is yet to be explored. Furthermore, we proposed to unravel the role of Viperin induction during Plasmodium liver infection. In vivo bioluminescence measurements revealed that mice lacking Viperin exhibited a higher liver stage burden compared with wild type mice at 42 hpi. The investigation of the cellular mediators of Viperin's expression in the liver was also performed through qRT-PCR and flow cytometry, identifying the hepatocytes and monocytes as the major sources of Viperin at 42 and 84 hpi, respectively. This thesis reveals a cell population exhibiting the type I interferon signature that may act as effectors on controlling either a primary or secondary infection. Moreover, knowledge on the role of Viperin can significantly contribute to the design of new antiplasmodial strategies by increasing the knowledge on the host-parasite interactions

New 4-(N-cinnamoylbutyl)aminoacridines as potential multi-stage antiplasmodial leads

© 2023 The Authors. Published by Elsevier Masson SAS. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).A novel family of 4-aminoacridine derivatives was obtained by linking this heteroaromatic core to different trans-cinnamic acids. The 4-(N-cinnamoylbutyl)aminoacridines obtained exhibited in vitro activity in the low- or sub-micromolar range against (i) hepatic stages of Plasmodium berghei, (ii) erythrocytic forms of Plasmodium falciparum, and (iii) early and mature gametocytes of Plasmodium falciparum. The most active compound, having a meta-fluorocinnamoyl group linked to the acridine core, was 20- and 120-fold more potent, respectively, against the hepatic and gametocyte stages of Plasmodium infection than the reference drug, primaquine. Moreover, no cytotoxicity towards mammalian and red blood cells at the concentrations tested was observed for any of the compounds under investigation. These novel conjugates represent promising leads for the development of new multi-target antiplasmodials.This work received financial support from PT national funds (FCT/MCTES, Fundação para a Ciência e Tecnologia and Ministério da Ciência, Tecnologia e Ensino Superior) through the project CIRCNA/BRB/0281/2019. The authors further thank FCT/MCTES for supporting Research Units LAQV-REQUIMTE (UIDB/50006/2020) and for the Doctoral Grant to MF (SRFH/BD/147354/2019). MP further acknowledges the “la Caixa” Foundation for Grant HR21-848. ISGlobal and IBEC are members of the CERCA Programme, Generalitat de Catalunya. We acknowledge support from the Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación (MCIN/AEI/ 10.13039/501100011033) through the “Centro de Excelencia Severo Ochoa 2019-2023” Program (CEX2018-000806-S). This research is part of ISGlobal's Program on the Molecular Mechanisms of Malaria which is partially supported by the Fundación Ramón Areces.info:eu-repo/semantics/publishedVersio

Pre-erythrocytic activity of M5717 in monotherapy and combination in preclinical Plasmodium infection models

Copyright © 2022 The Authors. Published by American Chemical SocietyCombination therapies have emerged to mitigate Plasmodium drug resistance, which has hampered the fight against malaria. M5717 is a potent multistage antiplasmodial drug under clinical development, which inhibits parasite protein synthesis. The combination of M5717 with pyronaridine, an inhibitor of hemozoin formation, displays potent activity against blood stage Plasmodium infection. However, the impact of this therapy on liver infection by Plasmodium remains unknown. Here, we employed a recently described 3D culture-based hepatic infection platform to evaluate the activity of the M5717-pyronaridine combination against hepatic infection by P. berghei. This effect was further confirmed in vivo by employing the C57BL/6J rodent Plasmodium infection model. Collectively, our data demonstrate that pyronaridine potentiates the activity of M5717 against P. berghei hepatic development. These preclinical results contribute to the validation of pyronaridine as a suitable partner drug for M5717, supporting the clinical evaluation of this novel antiplasmodial combination therapy.This work was funded by the healthcare business of Merck KGaA, Darmstadt, Germany (CrossRef Funder ID: 10.13039/100009945). M.P. is a recipient of a “Concurso de Estímulo ao Emprego Científico” Principal Investigator award of Fundação para a Ciência e Tecnologia, Portugal (FCT), with ref. N. CEECIND/03539/2017. D.F. is funded by FCT project CRCNA/BRB/0281/2019. F.A. is recipient of a PhD fellowship PD/BD/128371/2017, funded by FCT.info:eu-repo/semantics/publishedVersio

SARS-CoV-2 decreases malaria severity in co-infected rodent models

Coronavirus disease 2019 (COVID-19) and malaria, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Plasmodium parasites, respectively, share geographical distribution in regions where the latter disease is endemic, leading to the emergence of co-infections between the two pathogens. Thus far, epidemiologic studies and case reports have yielded insufficient data on the reciprocal impact of the two pathogens on either infection and related diseases. We established novel co-infection models to address this issue experimentally, employing either human angiotensin-converting enzyme 2 (hACE2)-expressing or wild-type mice, in combination with human- or mouse-infective variants of SARS-CoV-2, and the P. berghei rodent malaria parasite. We now show that a primary infection by a viral variant that causes a severe disease phenotype partially impairs a subsequent liver infection by the malaria parasite. Additionally, exposure to an attenuated viral variant modulates subsequent immune responses and provides protection from severe malaria-associated outcomes when a blood stage P. berghei infection was established. Our findings unveil a hitherto unknown host-mediated virus-parasite interaction that could have relevant implications for disease management and control in malaria-endemic regions. This work may contribute to the development of other models of concomitant infection between Plasmodium and respiratory viruses, expediting further research on co-infections that lead to complex disease presentations.info:eu-repo/semantics/publishedVersio

A review of novel heat transfer materials and fluids for aerospace applications

The issue of thermal control for space missions has been critical since the early space missions in the late 1950s. The demands in such environments are heightened, characterized by significant temperature variations and the need to manage substantial densities of heat. The current work offers a comprehensive survey of the innovative materials and thermal fluids employed in the aerospace technological area. In this scope, the materials should exhibit enhanced reliability for facing maintenance and raw materials scarcity. The improved thermophysical properties of the nanofluids increase the efficiency of the systems, allowing the mass/volume reduction in satellites, rovers, and spacecraft. Herein are summarized the main findings from a literature review of more than one hundred works on aerospace thermal management. In this sense, relevant issues in aerospace convection cooling were reported and discussed, using heat pipes and heat exchangers, and with heat transfer ability at high velocity, low pressure, and microgravity. Among the main findings, it could be highlighted the fact that these novel materials and fluids provide enhanced thermal conductivity, stability, and insulation, enhancing the heat transfer capability and preventing the malfunctioning, overheating, and degradation over time of the systems. The resulting indicators will contribute to strategic mapping knowledge and further competence. Also, this work will identify the main scientific and technological gaps and possible challenges for integrating the materials and fluids into existing systems and for maturation and large-scale feasibility for aerospace valorization and technology transfer enhancement.This work has been funded by FCT/MCTES (PIDDAC) through the base funding from the following research units: UIDP/50009/2020-FCT and UIDB/50009/2020-FCT, UIDB/00532/2020, LA/P/0045/2020, UIDB/04077/2020, and UIDP/04077/2020. The authors are also grateful for FCT funding through 2022. 03151.PTDC, PTDC/EME-TED/7801/2020, POCI-01-0145-FEDER-016861, POCI-01-0145-FEDER-028159, 2022. 02085.PTDC (https://doi.org/10.54499/2022.02085.PTDC, accessed on 25 March 2024), funded by COMPETE2020, NORTE2020, PORTUGAL2020, and FEDER. Glauco Nobrega was supported by the doctoral grant PRT/BD/153088/2021, financed by the Portuguese Foundation for Science and Technology (FCT), under the MIT Portugal Program. Pinho D. and Susana O. Catarino thank FCT for her contract funding provided through 2021.00027.CEECIND, 2020.00215.CEECIND (DOI: https://doi.org/10.54499/2020.00215.CEECIND/CP1600/CT0009, accessed on 25 March 2024), respectively. The authors are also grateful to the Fundação para a Ciência e a Tecnologia (FCT), Avenida D. Carlos I, 126, 1249–074 Lisboa, Portugal, for partially financing the Project “Estratégias interfaciais de arrefecimento para tecnologias de conversão com elevadas potências de dissipação”, ref. PTDC/EMETED/7801/2020, Associação do Instituto Superior Técnico para a Investigação e o Desenvolvimento (IST-ID). José Pereira also acknowledges FCT for his PhD fellowship (Ref. 2021. 05830.BD). The authors are also grateful for FCT funding through 2022.03151.PTD and LA/P/0083/2020 IN + -IST-ID. The authors are also grateful for FCT funding through 2022.03151.PTD and LA/P/0083/2020 IN + -IST-ID and through UIPD/50009/2020-FCT and UIDB/50009—FCT. Ana Moita also acknowledges FCT for partially financing her contract through CEECINST/00043/2021/CP2797/CT0005, doi:https://doi.org/10.54499/CEECINST/00043/2021/CP2797/CT0005, accessed on 25 March 2024. The authors also acknowledge Exército Português for their support through projects CINAMIL Desenvolvimento de Sistemas de Gestão Térmica e Climatização de equipamento NBQ and COOLUAV—Sistema de arrefecimento da componente eletrónica e baterias em veículos militares não tripulados

A genetically modified Plasmodium berghei parasite as a surrogate for whole-sporozoite vaccination against P. vivax malaria

© The Author(s) 2022. 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 license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license 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 license, visit http://creativecommons.org/licenses/by/4.0/.Two malaria parasite species, Plasmodium falciparum (Pf) and P. vivax (Pv) are responsible for most of the disease burden caused by malaria. Vaccine development against this disease has focused mainly on Pf. Whole-sporozoite (WSp) vaccination, targeting pre-erythrocytic (PE) parasite stages, is a promising strategy for immunization against malaria and several PfWSp-based vaccine candidates are currently undergoing clinical evaluation. In contrast, no WSp candidates have been developed for Pv, mainly due to constraints in the production of Pv sporozoites in the laboratory. Recently, we developed a novel approach for WSp vaccination against Pf based on the use of transgenic rodent P. berghei (Pb) sporozoites expressing immunogens of this human-infective parasite. We showed that this platform can be used to deliver PE Pf antigens, eliciting both targeted humoral responses and cross-species cellular immune responses against Pf. Here we explored this WSp platform for the delivery of Pv antigens. As the Pv circumsporozoite protein (CSP) is a leading vaccine candidate antigen, we generated a transgenic Pb parasite, PbviVac, that, in addition to its endogenous PbCSP, expresses PvCSP under the control of a strictly PE promoter. Immunofluorescence microscopy analyses confirmed that both the PbCSP and the PvCSP antigens are expressed in PbviVac sporozoites and liver stages and that PbviVac sporozoite infectivity of hepatic cells is similar to that of its wild-type Pb counterpart. Immunization of mice with PbviVac sporozoites elicits the production of anti-PvCSP antibodies that efficiently recognize and bind to Pv sporozoites. Our results warrant further development and evaluation of PbviVac as a surrogate for WSp vaccination against Pv malaria.A.D. and J.C.S. were supported by the National Institute of Allergy and Infectious Diseases, National Institutes of Health (U19AI110820 and R01AI141900). A.M.M. acknowledges Fundação para a Ciência e Tecnologia, Portugal (FCT) for Grant PTDC-BBB-BMD-2695-2014. M.P. acknowledges the “la Caixa” Foundation for Grant HR21-848, the GSK OpenLab Foundation for grant TC269, and FCT for grant PTDC-SAU-INF-29550-2017. D.M. acknowledges FCT for grant SFRH/BD/144817/2019.info:eu-repo/semantics/publishedVersio

The protein aggregation inhibitor YAT2150 has potent antimalarial activity in Plasmodium falciparum in vitro cultures

© The Author(s) 2022. 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/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.Background: By 2016, signs of emergence of Plasmodium falciparum resistance to artemisinin and partner drugs were detected in the Greater Mekong Subregion. Recently, the independent evolution of artemisinin resistance has also been reported in Africa and South America. This alarming scenario calls for the urgent development of new antimalarials with novel modes of action. We investigated the interference with protein aggregation, which is potentially toxic for the cell and occurs abundantly in all Plasmodium stages, as a hitherto unexplored drug target in the pathogen. Results: Attempts to exacerbate the P. falciparum proteome's propensity to aggregation by delivering endogenous aggregative peptides to in vitro cultures of this parasite did not significantly affect their growth. In contrast, protein aggregation inhibitors clearly reduced the pathogen's viability. One such compound, the bis(styrylpyridinium) salt YAT2150, exhibited potent antiplasmodial activity with an in vitro IC50 of 90 nM for chloroquine- and artemisinin-resistant lines, arresting asexual blood parasites at the trophozoite stage, as well as interfering with the development of both sexual and hepatic forms of Plasmodium. At its IC50, this compound is a powerful inhibitor of the aggregation of the model amyloid β peptide fragment 1-40, and it reduces the amount of aggregated proteins in P. falciparum cultures, suggesting that the underlying antimalarial mechanism consists in a generalized impairment of proteostasis in the pathogen. YAT2150 has an easy, rapid, and inexpensive synthesis, and because it fluoresces when it accumulates in its main localization in the Plasmodium cytosol, it is a theranostic agent. Conclusions: Inhibiting protein aggregation in Plasmodium significantly reduces the parasite's viability in vitro. Since YAT2150 belongs to a novel structural class of antiplasmodials with a mode of action that potentially targets multiple gene products, rapid evolution of resistance to this drug is unlikely to occur, making it a promising compound for the post-artemisinin era.This work was supported by grants (i) PCIN-2017-100, RTI2018-094579-B-I00 and PID2021-128325OB-I00 (XF-B), and SAF2017-82771-R and PID2020-118127RB-I00 (DM-T), funded by Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033 for grants PID2021- and PID2020-), which for grants RTI2018-, PID2021-, and SAF2017- included FEDER funds; (ii) ERA-NET Cofund EURONANOMED (http://euronanomed.net/), grant number 2017-178 (XF-B); and (iii) Generalitat de Catalunya, Spain (http://agaur.gencat.cat/), grant numbers 2017-SGR-908 (XF-B) and 2017-SGR-106 (DM-T). Work at Pompeu Fabra University was supported by the “La Caixa” Banking Foundation (https://fundacionlacaixa.org/, grant HR17-00409), and by grant AGL2017-84097-C2-2-R and the “María de Maeztu” Program for Units of Excellence in R&D from the Spanish Ministry of Science, Innovation and Universities.info:eu-repo/semantics/publishedVersio

Organ-on-a-chip platforms for drug screening and delivery in tumor cells: a systematic review

The development of cancer models that rectify the simplicity of monolayer or static cell cultures physiologic microenvironment and, at the same time, replicate the human system more accurately than animal models has been a challenge in biomedical research. Organ-on-a-chip (OoC) devices are a solution that has been explored over the last decade. The combination of microfluidics and cell culture allows the design of a dynamic microenvironment suitable for the evaluation of treatments’ efficacy and effects, closer to the response observed in patients. This systematic review sums the studies from the last decade, where OoC with cancer cell cultures were used for drug screening assays. The studies were selected from three databases and analyzed following the research guidelines for systematic reviews proposed by PRISMA. In the selected studies, several types of cancer cells were evaluated, and the majority of treatments tested were standard chemotherapeutic drugs. Some studies reported higher drug resistance of the cultures on the OoC devices than on 2D cultures, which indicates the better resemblance to in vivo conditions of the former. Several studies also included the replication of the microvasculature or the combination of different cell cultures. The presence of vasculature can influence positively or negatively the drug efficacy since it contributes to a greater diffusion of the drug and also oxygen and nutrients. Co-cultures with liver cells contributed to the evaluation of the systemic toxicity of some drugs metabolites. Nevertheless, few studies used patient cells for the drug screening assays.This work has been supported by the projects NORTE-01-0145-FEDER-030171 (project reference PTDC/EME-SIS/30171/2017), NORTE-01-0145-FEDER-029394 (project reference PTDC/EMDEMD/29394/2017), through the COMPETE2020, the Lisb@2020, the Programa Operacional Regional do Norte–Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement through the European Regional Development Fund (FEDER) and by Fundação para a Ciência e Tecnologia (FCT), and through FEDER and FCT, project references EXPL/EMD-EMD/0650/2021 and PTDC/EEI-EEE/2846/2021. The authors also acknowledge the partial financial support within the R&D Units Project Scope: UIDB/00319/2020, UIDB/04077/2020, UIDB/00690/2020, UIDB/04436/2020. This work was also funded by AMED-CREST Grant Number JP20gm1310001h0002. Raquel O. Rodrigues (R.O.R.) thanks FCT for her contract funding provided through 2020.03975.CEECIND

Sensitivity improvement of a humidity sensor based on silica nanospheres on a long-period fiber grating

This work addresses a new configuration that improves the sensitivity of a humidity sensor based on a long-period fiber grating coated with a SiO(2)-nanospheres film. An intermediate higher refractive index overlay, deposited through Electrostatic Self-Assembly, is placed between the fiber cladding and the humidity sensitive film in order to increase the total effective refractive index of the coating. With this intermediate design, a three-fold improvement in the sensitivity was obtained. Wavelength shifts up to 15 nm against 5 nm were achieved in a humidity range from 20% to 80%.This work was supported in part by Fundação para a Ciência e Tecnologia (FCT) with the grant SFRH/BD/30086/200