Acta tropica最新文献

{"title":"Bioassay-guided isolation of insect repellent compounds from Ligusticum porteri root extract","authors":"Abbas Ali ,&nbsp;Nurhayat Tabanca ,&nbsp;Zulfiqar Ali ,&nbsp;Betul Demirci ,&nbsp;Ikhlas A. Khan","doi":"10.1016/j.actatropica.2024.107386","DOIUrl":"10.1016/j.actatropica.2024.107386","url":null,"abstract":"<div><p>In our program of screening natural products against the pests of medical and veterinary importance, ethanolic extract of the roots of <em>Ligusticum porteri</em> J.M.Coult. &amp; Rose showed significant repellency against mosquitoes. The extract was then fractionated to test different fractions to identify the active repellent compounds. This testing resulted in the isolation of different compounds including (<em>Z</em>)-3-butylidenephthalide, (<em>E</em>)-3-butylidenephthalide, and a mixture of (<em>E/Z</em>)-3-butylidenephthalide. Biting deterrence of all these compounds was similar to <em>N,N</em>-diethyl-3-methylbenzamide (DEET) against <em>Aedes aegypti</em> (L.) in Klun and Debboun (K &amp; D) bioassay. (<em>E/Z</em>)-3-butylidenephthalide which is a mixture of the two compounds was further tested in Ali &amp; Khan (A &amp; K) bioassay. Based on these data repellency of this compound was similar whereas the MED values of the mixtures of (<em>E/Z</em>)-3-butylidenephthalide with carotol were lower (6.25 + 6.25 = 12.5 µg/cm²) than individual treatments (25 µg/cm²). In <em>in vivo</em> (direct skin application bioassay), (<em>E/Z</em>)-3-butylidenephthalide showed excellent repellency. The residual repellency of (<em>E/Z</em>)-3-butylidenephthalide at 8 and 16 % application rates was 4.5 and 10-h respectively which was equal to or better than DEET with the residual time of 5 and 9-h, respectively. The mixture of (<em>E/Z</em>)-3-butylidenephthalide with carotol (8 + 8 %) increased the residual repellency by 2-h (44 %) as compared to (<em>E/Z</em>)-3-butylidenephthalide alone at a dose of 8 %. These data indicated that (<em>E/Z</em>)-3-butylidenephthalide is an effective mosquito repellent that is stable and has a long shelf life. The activity of this compound is extraordinary and residual time is comparable to DEET. <em>In vivo</em> data demonstrated an enormous potential of (<em>E/Z</em>)-3-butylidenephthalide as a repellent that can be developed for commercial use. However, (E/Z)-3-butylidenephthalate was found in lower amounts of the L. <em>porteri</em> essential oil.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0001706X24002687/pdfft?md5=6720f26e7621439e031cd72fd5ece949&pid=1-s2.0-S0001706X24002687-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142229162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Triatomine (Hemiptera: Reduviidae) populations and Trypanosoma cruzi genotyping in peridomestic and sylvatic environments in the semiarid region of Sergipe, Northeastern, Brazil","authors":"Felipe Mendes Fontes ,&nbsp;Jader de Oliveira ,&nbsp;André Luiz Rodrigues Menezes ,&nbsp;Marta Maria Geraldes Teixeira ,&nbsp;David Campos Andrade ,&nbsp;João Aristeu da Rosa ,&nbsp;Rubens Riscala Madi ,&nbsp;Cláudia Moura de Melo","doi":"10.1016/j.actatropica.2024.107385","DOIUrl":"10.1016/j.actatropica.2024.107385","url":null,"abstract":"<div><p>We assessed the diversity of triatomines, the rates of natural infection, and the discrete typing units (DTUs) of <em>Trypanosoma cruzi</em> isolated from them in two municipalities in the state of Sergipe, Brazil. Active searches for triatomines were conducted in the peridomicily and wild enviroments of 10 villages within the two municipalities. Triatomines were taxonomically identified and their feces were extracted using the abdominal compression method. Parasite detection was performed using optical microscopy. For <em>Trypanosoma cruzi</em> genotyping via PCR-FFLB, 151 samples of the subspecies <em>Triatoma brasiliensis macromelasoma</em> and <em>Triatoma brasiliensis</em> were isolated from both municipalities. In total, 505 triatomines were collected, with <em>Triatoma brasiliensis macromelasoma</em> being the most frequent species (58.81 %). <em>Triatoma b. brasiliensis</em> was the only species in both peridomestic and wild environments. Regarding the other species, <em>T. pseudomaculata</em> was found only in the peridomestic environment; and <em>T. b. macromelasoma</em> and <em>Psammolestes tertius</em> were found in the wild environment. Three Discrete Typing Units were identified: TcI (87.51 %) detected in <em>T. b. brasiliensis</em> and <em>T. b. macromelasoma</em>, TcI+TcIII (10.41 %) in <em>T. b. macromelasoma</em>, and TcI+<em>Trypanosoma rangeli</em> (2.08 %) in <em>T. b. macromelasoma</em>. It is concluded that <em>T. b. macromelasoma</em> is the species collected most frequently in the studied region and the one that presents the highest rates of natural infection, highlighting its epidemiological importance for the vectorial transmission of Chagas disease in Sergipe.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142171939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Taxonomic history, biology and ecology of Culex (Microculex) (Diptera: Culicidae)","authors":"Rafael Oliveira-Christe,&nbsp;Mauro Toledo Marrelli","doi":"10.1016/j.actatropica.2024.107387","DOIUrl":"10.1016/j.actatropica.2024.107387","url":null,"abstract":"<div><p><em>Microculex</em> is a subgenus of <em>Culex</em> that is mainly associated with natural breeding sites in wild environments such as cut bamboos, tree holes and bromeliads. However, recent findings of <em>Culex</em> (<em>Microculex</em>) species in bromeliads in urban areas and in artificial breeding sites close to human habitations suggest that they are becoming more tolerant of urbanization. Whilst dispersion studies of this subgenus have shown the ecological valency of some species in relation to human-impacted areas, there is a scarcity of studies on the blood-feeding habits, vector capacity and taxonomy of <em>Microculex</em>. As all the information about this subgenus is fragmented and restricted in most cases to physical libraries, this review seeks to compile all the information on <em>Microculex</em> published over the last century and a half so that this can be more easily consulted by specialists interested in the subject. The ability of some species of this subgenus to adapt to human-impacted environments by colonizing artificial breeding sites and thus become a potential vector of animal and human diseases is also discussed.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142171937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rational design of a multi-epitope vaccine against heartland virus (HRTV) using immune-informatics, molecular docking and dynamics approaches","authors":"Mohammad Z. Ahmed,&nbsp;Ali S. Alqahtani,&nbsp;Md. Tabish Rehman","doi":"10.1016/j.actatropica.2024.107388","DOIUrl":"10.1016/j.actatropica.2024.107388","url":null,"abstract":"<div><p>Heartland virus (HRTV) is a single-stranded negative-sense RNA virus that infects human beings. Because there are no antiviral medications available to treat HRTV infection, supportive care management is used in cases of severe disease. Therefore, it has spurred research into developing a multi-epitope vaccine capable of providing effective protection against HRTV infection. A multi-epitope vaccine was created using a combination of immuno-informatics, molecular docking and molecular dynamics simulation in this investigation. The HRTV proteome was utilized to predict B-cell, T-cell (HTL and CTL), and IFN-epitopes. Following prediction, highly antigenic, non-allergenic and immunogenic epitopes were chosen, including 6 CTL, 8 HTL, and 5 LBL epitopes that were connected to the final peptide by AAY, GPGPG, and KK linkers, respectively. An adjuvant was introduced to the vaccine's N-terminal through the EAAAK linker to increase its immunogenicity. Following the inclusion of linkers and adjuvant, the final construct has 359 amino acids. The presence of B-cell and IFN-γ-epitopes validates the construct's acquired humoral and cell-mediated immune responses. To ensure the vaccine's safety and immunogenicity profile, its allergenicity, antigenicity, and various physicochemical characteristics were assessed. Docking was used to assess the binding affinity and molecular interaction between the vaccination and TLR-3. <em>In silico</em> cloning was used to confirm the construct's validity and expression efficiency. The results of these computer assays demonstrated that the designed vaccine is highly promising in terms of developing protective immunity against HRTV; nevertheless, additional <em>in vivo</em> and <em>in vitro</em> investigations are required to validate its true immune-protective efficiency.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction and validation of a novel multi-epitope in silico vaccine design against the paramyosin protein of Opisthorchis viverrini using immunoinformatics analyses","authors":"Alok Kafle ,&nbsp;Jan Clyden B. Tenorio ,&nbsp;Roshan Kumar Mahato ,&nbsp;Sahara Dhakal ,&nbsp;Muhammad F. Heikal ,&nbsp;Sutas Suttiprapa","doi":"10.1016/j.actatropica.2024.107389","DOIUrl":"10.1016/j.actatropica.2024.107389","url":null,"abstract":"<div><p>Liver fluke infection caused by <em>Opisthorchis viverrini</em> (<em>O. viverrini</em>) remains a significant but neglected health threat across Southeastern Asia. The early infective anabolic growth stage of <em>O. viverrini</em> expresses and exposes proteins integral for the growth and maturation of immature worms to the adult catabolic stage. Among these proteins, paramyosin emerged as a distinct immunogenic protein during opisthorchiasis. The functional region of the paramyosin protein known as myosin tail was selected to design a multi-epitope vaccine (MEV) to elicit T and B cell immune responses in susceptible human hosts utilizing various immunoinformatics and <em>in silico</em> vaccinology tools. The vaccine candidate had several B- and T-cell epitopes that stimulate both humoral and cellular immune responses. Moreover, <em>in silico</em> structural, docking, and dynamic analyses showed that the construct interacted with target immune receptors effectively, which may result in sufficient immunological stimulation. Analysis of simulated coverage efficacy also supports vaccine application in the field. Cloning and expression of the vaccine candidate were determined to be viable based on physicochemical and <em>in silico</em> assessments. These results reveal that the vaccine candidate developed herein is stable and potentially useful in addressing opisthorchiasis. The promising result of this study establishes a strong platform for initiating laboratory and efficacy trials for the vaccine candidate.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification and characterization of Jingmen tick virus from Rhipicephalus microplus in Hunan, China","authors":"Li Zhang ,&nbsp;Wenbo Xu ,&nbsp;Yinghua Zhao ,&nbsp;Liyan Sui ,&nbsp;Mingxin Song ,&nbsp;Quan Liu","doi":"10.1016/j.actatropica.2024.107378","DOIUrl":"10.1016/j.actatropica.2024.107378","url":null,"abstract":"<div><p>Jingmen tick virus (JMTV) is a tick-borne pathogen known to affect human beings, characterized by a segmented genome structure that defies the conventional understanding of the <em>Flaviviridae</em> family. In the present study, we employed metagenomic analysis to screen for tick-borne viruses in Hunan Province, China, and identified five JMTV variants with complete genomes from <em>Rhipicephalus microplus</em> ticks sampled from cattle. These viral strains exhibited the highest sequence similarity to JMTV isolates previously reported in Hubei Province, China. However, evidence of genomic reassortment was detected, particularly with the S2 segment showing greater similarity to the strains from Japan. Phylogenetic analysis demonstrated that JMTV strains cluster predominantly based on their geographic origin. In agreement with the homology data, the S1, S3, and S4 segments of the strains identified in this study grouped with those from Hubei Province, while the S2 segment displayed a distinct topological structure. Moreover, JMTV displayed limited replication in mammal-derived cells, but thrived in tick-derived cell lines. In addition to the commonly used <em>R. microplus</em>-derived BME/CTVM23 cells, we found that JMTV also proliferated robustly in both <em>Ixodes scapularis</em>-derived ISE6 and <em>Ixodes ricinus</em>-derived IRE/CTVM19 cells, offering new avenues for <em>in vitro</em> production of the virus. In summary, this study expands the known geographic distribution and genetic diversity of JMTV, providing valuable insights into its epidemiology and potential for <em>in vitro</em> cultivation.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COI DNA barcoding to differentiate Haemagogus janthinomys and Haemagogus capricornii (Diptera: Culicidae) mosquitoes","authors":"Juliana Telles-de-Deus ,&nbsp;Lilian de Oliveira Guimarães ,&nbsp;Esmenia Coelho Rocha ,&nbsp;Vanessa Christe Helfstein ,&nbsp;Simone Luchetta Reginato ,&nbsp;Luis Filipe Mucci ,&nbsp;Eduardo Sterlino Bergo ,&nbsp;Vera Lucia Fonseca de Camargo-Neves ,&nbsp;Karin Kirchgatter","doi":"10.1016/j.actatropica.2024.107377","DOIUrl":"10.1016/j.actatropica.2024.107377","url":null,"abstract":"<div><p>The genus <em>Haemagogus</em> (Diptera: Culicidae) includes species that are important vectors of pathogens such as the yellow fever virus. The accurate identification of these species is essential for the control of zoonoses. Females of <em>Hg. capricornii</em> and <em>Hg. janthinomys</em> are morphologically indistinguishable, which makes the use of alternative identification techniques desirable. This study aimed to obtain sequences of the mitochondrial cytochrome c oxidase I (COI) gene, in the region widely used for DNA barcoding, of <em>Haemagogus</em> specimens from the state of São Paulo, Brazil, to evaluate the effectiveness of these sequences in the molecular identification of the species. A total of 37 female and 2 male mosquitoes were collected in various locations in the state of São Paulo, using methods such as hand-nets, Shannon traps, CDC light traps with CO₂ bait and Nasci aspirators. The sequences of a 710 bp fragment of the COI gene were amplified by PCR and sequenced. A phylogenetic tree reconstruction was conducted using the Bayesian approach implemented in MrBayes v3.2.2, providing support values for taxa where genetic clusters may indicate the presence of new or cryptic species. We obtained 39 COI sequences representing three species: <em>Haemagogus capricornii, Haemagogus leucocelaenus</em>, and <em>Haemagogus janthinomys</em>. Bayesian analysis of the sequences produced clades that corroborate the morphological identification of the species. The separation of <em>Hg. capricornii</em> and <em>Hg. janthinomys</em> received 100 % statistical support and the <em>Hg. capricornii</em> was very well supported (91 %). The two sequences from male specimens, morphologically identified as <em>Hg. capricornii</em>, were grouped in the same clade, a sister clade of <em>Hg. janthinomys</em>. It is important to highlight that the <em>Hg. janthinomys</em> were positioned in several subclades, showing a polymorphism of this species within the state, a situation not observed for <em>Hg. capricornii</em>. For the first time, sequences of the mtCOI gene from <em>Hg. capricornii</em> were obtained and related to morphologically identified specimens. COI sequences proved effective in the molecular identification of <em>Haemagogus</em> species. This study contributes to the expansion of the GenBank database, providing the first sequences of <em>Hg. capricornii</em> and new sequences for <em>Hg. janthinomys</em> and <em>Hg. leucocelaenus</em>.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0001706X24002596/pdfft?md5=e89024d8ddaa7bf520d17d89235707b0&pid=1-s2.0-S0001706X24002596-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tick-associated Trypanosoma species (Apicomplexa: Kinetoplastida) from cattle ticks (Acari: Ixodidae) in Peninsular Malaysia","authors":"Abdul Rahman Kazim ,&nbsp;Van Lun Low ,&nbsp;Jamal Houssaini ,&nbsp;Dennis Tappe ,&nbsp;Chong Chin Heo","doi":"10.1016/j.actatropica.2024.107383","DOIUrl":"10.1016/j.actatropica.2024.107383","url":null,"abstract":"<div><p>A <em>Trypanosoma</em> screening was conducted on 130 pools comprising 1,241 ticks, collected from 674 selected farm ruminants in Peninsular Malaysia. Of these, nine pools were tested positive for <em>Trypanosoma</em>. Subsequent BLAST searches revealed that the 18S rRNA gene sequences were closely related to <em>Trypanosoma rhipicephalis</em> isolate Chaco CB, with percentage similarities ranging from 95.56 % to 99.84 %. Phylogenetic analysis showed that three of the nine sequences formed a clade with <em>Trypanosoma rhipicephalis</em>. The remaining six <em>Trypanosoma</em> sequences formed a distinct clade, separate from <em>T. rhipicephalis</em> and other <em>Trypanosoma</em> species, with genetic distances of 4.34 % and 4.33–4.58 %, respectively. This study marks the first report of tick-associated <em>Trypanosoma</em> in Malaysia and underscores significant research gaps regarding trypanosome interactions with tick hosts in the region.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In silico and in vitro evaluation of the immunogenic potential of Leishmania donovani ascorbate peroxidase and its derived peptides","authors":"Shobha Kumari ,&nbsp;Saravanan Vijaykumar ,&nbsp;Vikash Kumar ,&nbsp;Ravi Ranjan ,&nbsp;Dayakar Alti ,&nbsp;Veer Singh ,&nbsp;Ghufran Ahmed ,&nbsp;Ganesh Chandra Sahoo ,&nbsp;Krishna Pandey ,&nbsp;Ashish Kumar","doi":"10.1016/j.actatropica.2024.107381","DOIUrl":"10.1016/j.actatropica.2024.107381","url":null,"abstract":"<div><div>The control and eradication of any infectious disease is only possible with a potential vaccine, which has not been accomplished for human visceral leishmaniasis (VL). The lack of vaccines may increase the risk of VL outbreaks periodically in endemic zones. Identifying a reliable vaccine candidate for <em>Leishmania</em> is a major challenge. Here, we considered <em>Leishmania donovani</em> ascorbate peroxidase (<em>Ld</em>APx) for its in vitro evaluation with the hope of future vaccine candidates for VL. <em>Ld</em>APx was selected based on its unique presence in <em>Leishmania</em> and virulence in VL pathogenesis. Initially, we found antibodies against recombinant <em>Ld</em>APx (r<em>Ld</em>APx) in the serum of VL patients. Therefore, using bioinformatics, we predicted and selected ten (MHC class I and II) peptides. These peptides, evaluated in vitro with PBMCs from healthy, active VL, and treated VL individuals induced PBMC proliferation, IFN-γ secretion, and Nitric Oxide (NO) production, indicating host-protective immune responses. Among them, three peptides (PEP6, PEP8, and PEP9) consistently elicited a Th1-type immune response in PBMCs. Treated VL individuals showed a stronger Th1 response compared to active VL patients and healthy subjects, highlighting these peptides' potential as vaccine candidates. Further studies are on the way toward evaluating the <em>Ld</em>APx-derived peptides or sub-unit vaccine in animal models against the <em>L. donovani</em> challenge.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142144934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterisation of the erythrocyte invasion phenotype of FCB-2: A South American P. falciparum reference strain","authors":"Monica Ararat-Sarria ,&nbsp;Hernando Curtidor ,&nbsp;Manuel Alfonso Patarroyo","doi":"10.1016/j.actatropica.2024.107379","DOIUrl":"10.1016/j.actatropica.2024.107379","url":null,"abstract":"<div><p>The extent of parasite adaptive capability involved in erythrocyte invasion represents a significant challenge for the development of a <em>Plasmodium falciparum</em> vaccine. The parasite's geographical and populational origin may influence such adaptive behaviour; <em>in vitro</em> culture-adapted parasite strains are typically used for such studies. Previous studies have reported invasion phenotypes in strains from Africa and Asia and, to a lesser extent, from Latin America. This study was aimed at expanding the pool of characterised parasite strains from Latin America by describing the invasion phenotype of the <em>P. falciparum</em> Colombia Bogotá 2 (FCB2) strain. The FCB2 genome was sequenced and erythrocyte invasion ligand sequences were analysed and compared to other previously reported ones. RT-PCR was used for assessing <em>Pfeba</em> family erythrocyte invasion ligands and reticulocyte binding homologue (<em>Pfrh</em>) gene transcription. A flow cytometry-based erythrocyte invasion assay (using enzymatically-treated erythrocytes) was used for determining the FCB2 strain's invasion phenotype. The <em>P. falciparum</em> FCB2 genome sequence was analysed, bearing in mind that prolonged <em>in vitro</em> parasite culture may affect its genome sequence and, in some cases, lead to the deletion of certain genes; it was demonstrated that all erythrocyte invasion ligand gene sequences studied here were preserved. Comparative analysis showed that the target genome sequences were conserved whereas transcriptional analysis highlighted <em>Pfebas</em> and <em>Pfrhs</em> gene expression. Erythrocyte invasion analysis demonstrated that the FCB2 strain has a sialic acid-resistant invasion phenotype.</p></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}