ScienceOpenJul 31, 2025

📙🆕 'Impact of the number of microsatellite markers on the analysis of population genetic diversity of Schistosoma japonicum' - an article in the Chinese Journal of #Schistosomiasis Control on #ScienceOpen:

🔗 https://www.scienceopen.com/document?vid=d25578bf-f59c-4b6e-9d76-3d0a432b7831

#ParasitologyResearch #PopulationGenetics #MicrosatelliteMarkers #GeneticDiversity

Impact of the number of microsatellite markers on the analysis of population genetic diversity of <i>Schistosoma japonicum</i>

<p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d2987433e134"> <b>Objective</b> To examine the impact of different numbers of microsatellite markers on the analysis of population genetic diversity of <i>Schistosoma japonicum</i>, so as to provide insights into studies on the population genetic diversity of <i>S. japonicum</i>. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d2987433e145"> <b>Methods</b> <i>Oncomelania hupensis</i> snails were collected from a wasteland in Gong’an County, Hubei Province, and 37 <i>S. japonicum</i>-infected <i>O. hupensis</i> snails were identified using the cercarial shedding method. A single cercaria released from each <i>S. japonicum</i>-infected <i>O. hupensis</i> snail was collected, and 10 cercariae were randomly collected from DNA extraction. Nine previously validated microsatellite loci and 15 additional microsatellite loci screened from literature review and the GenBank database and confirmed with stable amplification efficiency were selected as molecular markers. Genomic DNA from cercariae was subjected to three multiplex PCR amplifications of microsatellite markers with the Type-it Microsatellite PCR kit, and genotyped using capillary electrophoresis. The population genetic diversity of <i>S. japonicum</i> cercariae DNA was analyzed with observed number of alleles ( <i>Na</i>), effective number of alleles ( <i>Ae</i>), observed heterozygosity ( <i>Ho</i>), expected heterozygosity ( <i>He</i>), and polymorphism information content (PIC), and tested for Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD). To further investigate the impact of the number of microsatellite loci on the population genetic diversity of <i>S. japonicum</i>, the number of microsatellite markers was sequentially assigned from 1 to 24, and the mean and standard deviation of <i>Na</i> were calculated for <i>S. japonicum</i> populations at different locus numbers. In addition, the coefficient of variation ( <i>CV</i>) of allelic number (defined as the ratio of the standard deviation to the mean) was determined, and the variation in <i>Na</i> with increasing microsatellite locus numbers was analyzed. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d2987433e197"> <b>Results</b> Genomic DNA from 345 <i>S. japonicum</i> cercariae was selected for genotyping of 24 microsatellite markers, and all 24 microsatellite loci met linkage equilibrium (standardized linkage disequilibrium coefficient <i>D</i>′ < 0.7, <i>r</i> <sup>2</sup> < 0.3) and deviated from Hardy-Weinberg equilibrium ( <i>P</i> < 0.001). The mean <i>Na</i>, <i>Ae</i>, <i>Ho</i> and <i>He</i> were 27.46 ± 2.18, 12.46 ± 0.95, 0.46 ± 0.03, and 0.91 ± 0.01 for 24 microsatellite loci in <i>S. japonicum</i> cercarial populations, respectively, and PIC ranged from 0.85 to 0.96, indicating high genome-wide representativeness of 24 microsatellite loci. The mean value of <i>Na</i>- <i>Ae</i> was higher in genotyping with 9 previously validated microsatellite loci (19.88 ± 8.43) than with all 24 loci (14.99 ± 8.09). As the number of microsatellite loci increased, the mean <i>Na</i> showed no significant variation; however, the standard deviation gradually decreased. Notably, if the locus number reached 18 or more, the variation in the standard deviation of <i>Na</i> remarkably reduced. In addition, the standard deviation of <i>Na</i> at 18 loci was less than 5% of the mean <i>Na</i> at 24 loci, with a <i>CV</i> of 4.6%. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d2987433e256"> <b>Conclusions</b> The number of microsatellite loci significantly affects the population genetic diversity analysis of <i>S. japonicum</i>. Eighteen or more microsatellite loci are recommended for analysis of the population genetic diversity of <i>S. japonicum</i> under the current conditions of low-prevalence infection and unbalanced genetic distribution of <i>S. japonicum</i>. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="first" dir="auto" id="d2987433e271"> <b>［摘要］ 目的</b> 探究采用不同数量微卫星位点标记对日本血吸虫种群遗传多样性分析的影响, 为日本血吸虫种群遗传 学研究提供参考。 <b>方法</b> 自湖北省公安县某地野外荒滩采集湖北钉螺, 采用直管逸蚴法筛选出 37 只血吸虫感染性钉 螺。分别收集每只感染性钉螺逸出的单条尾蚴, 各随机挑选 10 条尾蚴提取DNA。以前期经大规模样本验证过的 9 个微 卫星位点以及自参考文献和GenBank 数据库中筛选且可稳定扩增的 15 个微卫星位点作为分子标记, 利用Type-it 微卫星 PCR 试剂盒对上述尾蚴DNA进行 3 组 8 重微卫星PCR扩增, 通过毛细管电泳检测样本基因型。对上述日本血吸虫尾蚴 DNA进行种群遗传多样性分析, 评估等位基因数 (observed number of alleles, <i>Na</i>)、有效等位基因数 (effective number of alleles, <i>Ae</i>)、观察杂合度 (observed heterozygosity, <i>Ho</i>)、期望杂合度 (expected heterozygosity, <i>He</i>) 和多态信息含量 (polymorphism information content, PIC) 等多态性指标, 采用 Hardy-Weinberg 平衡检验和连锁不平衡评估进行尾蚴种群遗传结构 分析。此外, 为进一步探究微卫星位点数量对日本血吸虫种群遗传多样性的影响, 依次将微卫星位点数量设定为 1~24 个, 计算不同位点数量时日本血吸虫种群 <i>Na</i> 均数及其标准差, 并计算等位基因数变异系数, 观察 <i>Na</i> 随微卫星位点数量 增加的变化。 <b>结果</b> 共选取 345 条日本血吸虫尾蚴DNA, 用上述 24 个微卫星位点进行检测, 结果显示全部位点均满足 连锁平衡标准化[连锁不平衡系数 ( <i>D</i>′) < 0.7, <i>r</i> <sup>2</sup> < 0.3)], 均偏离Hardy-Weinberg平衡 ( <i>P</i> < 0.001)。日本血吸虫尾蚴种群 在 24 个微卫星位点的 <i>Na</i>、 <i>Ae</i>、 <i>Ho</i> 和 <i>He</i> 均值分别为27.46 ± 2.18、12.46 ± 0.95、0.46 ± 0.03和0.91 ± 0.01, PIC 值为 0.85~0.96, 提示 24 个位点在全基因组微卫星水平上均具有较好的代表性。采用经前期验证的 9 个微卫星位点进行分析时, 日 本血吸虫种群 <i>Na</i>- <i>Ae</i> 均值为 19.88 ± 8.43, 高于使用全部 24 个位点分析时的结果 (14.99 ± 8.09)。随着微卫星位点数量的 增加, <i>Na</i> 均值虽无明显变化, 但标准差逐渐变小; 尤其是当位点数为 18 个及以上时, 标准差变化幅度明显减小; 当位点数 为 18 个时, <i>Na</i> 标准差小于位点数为 24 个时 <i>Na</i> 均值的5%, 变异系数为4.6%。 <b>结论</b> 微卫星位点数量可显著影响日本血 吸虫种群遗传多样性分析结果。在目前低感染率和血吸虫遗传分布不平衡的背景下, 推荐选取≥18个微卫星位点进行 日本血吸虫种群遗传多样性分析。 </p>

ScienceOpen
ScienceOpenJul 31, 2025

📣 New issue alert for the Chinese Journal of #SchistosomiasisControl!

📙 A leading scientific journal advancing research and practice in the field of #Schistosomiasis and other #ParasiticDiseases.

👉 https://www.scienceopen.com/collection/ChinJSchistoControl

Chinese Journal of Schistosomiasis Control

<p><em>Chinese Journal of Schistosomiasis Control </em>is a leading scientific journal for advancing the research and practice in the field of schistosomiasis and other parasitic diseases and their control in China. It is a professional journal to report on the developments and the latest trends related to schistosomiasis and other parasitic diseases across the world.</p>

ScienceOpen
ScienceOpenMay 28, 2025
'Proportions of memory T cells and expression of their associated cytokines in lymph nodes of mice infected with Echinococcus multilocularis' - a #Research article in the Chinese Journal of #Schistosomiasis Control on #ScienceOpen: https://www.scienceopen.com/document?vid=70b368f5-8810-4e57-8707-0feb6546725d
Proportions of memory T cells and expression of their associated cytokines in lymph nodes of mice infected with <i>Echinococcus multilocularis</i>

<p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d8563416e215"> <b>Objective</b> To investigate the effects of <i>Echinococcus multilocularis</i> infection on levels of memory T (Tm) cells and their subsets in lymph nodes of mice at different stages of infection, so as to provide new insights into immunotherapy for alveolarechinococcosis. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d8563416e223"> <b>Methods</b> Twenty-four C57BL/6J mice aged 6 to 9 weeks were randomly divided into the infection group and the control group, of 12 mice in each group. Mice in the infection group were administered with 3 000 <i>E. multilocularis</i> protoscoleces via portal venous injection, while animals in the control group were administered with an equal volume of physiological saline. Three mice from each group were sacrificed 4, 12 weeks and 24 weeks post-infection, and lymph nodes were sampled and stained with hematoxylin and eosin (HE) to investigate the histopathological changes of mouse lymph nodes in the infection group. The expression and localization of T lymphocyte surface markers CD3, CD4, and CD8 were observed in mouse lymph nodes using immunohistochemical staining. In addition, lymphocyte suspensions were prepared from mouse lymph nodes in both groups at different time points post-infection, and the levels of Tm cell subsets and their secreted cytokines were detected using flow cytometry. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d8563416e231"> <b>Results</b> HE staining showed diffuse structural alterations in the subcapsular cortical and paracortical regions of mouse lymph nodes in the infection group 4 weeks post-infection with <i>E. multilocularis</i>. Immunohistochemical staining detected CD3, CD4 and CD8 expression in mouse lymph nodes in both groups. Flow cytometry revealed higher proportions of CD4 <sup>+</sup> Tm cells [(55.3 ± 4.8)% vs. (38.8 ± 6.1)%; <i>t</i> = -4.259, <i>P</i> < 0.05] and CD4 <sup>+</sup> tissue-resident Tm (Trm) cells [(57.7 ± 3.7)% vs. (34.1 ± 11.2)%; <i>t</i> = -3.990, <i>P</i> < 0.05] in mouse lymph nodes in the infection group than in the control group 4 weeks post-infection, and higher proportions of CD4 <sup>+</sup> Tm cells [(34.6 ± 3.2)% vs. (23.3 ± 7.5)%; <i>t</i> = -2.764, <i>P</i> < 0.05] and CD4 <sup>+</sup> Trm cells [(44.0 ± 1.9)% vs. (31.2 ± 1.5)%; <i>t</i> = -4.039, <i>P</i> < 0.05] in mouse lymph nodes in the infection group than in the control group 24 weeks post-infection. The proportions of CD8 <sup>+</sup> Tm cells were higher in the infection group than in the control group 4 weeks [(56.8 ± 2.7)% vs. (43.9 ± 5.2)%; <i>t</i> = -4.416, <i>P</i> < 0.01] and 12 weeks post-infection [(25.4 ± 2.7)% vs. (12.0 ± 2.6)%; <i>t</i> = -2.552, <i>P</i> < 0.05], while the proportions of tumor necrosis factor (TNF)-α <sup>+</sup> CD4 <sup>+</sup> T cells [(15.7 ± 5.0)% vs. (49.4 ± 6.4)%; <i>t</i> = 7.150, <i>P</i> < 0.01], TNF-α <sup>+</sup>CD8 <sup>+</sup> T cells [(20.7 ± 5.5)% vs. (57.5 ± 8.4)%; <i>t</i> = -6.694, <i>P</i> < 0.01], and TNF-α <sup>+</sup> CD8 <sup>+</sup> Tm cells [7.0% (1.0%) vs. 31.0% (11.0%); <i>Z</i> = -2.236, <i>P</i> < 0.05] were lower in the infection group than in the control group 24 weeks post-infection. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d8563416e331"> <b>Conclusions</b> Tm cells levels are consistently increased in lymph nodes of mice at different stages of <i>E. multilocularis</i> infection, with Trm cells as the predominantly elevated subset. The impaired capacity of CD8 <sup>+</sup> Tm cells to secrete the effector molecule TNF-α in mouse lymph nodes at the late-stage infection may facilitate chronic parasitism of <i>E. multilocularis</i>. </p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="first" dir="auto" id="d8563416e346"> <b>［摘要］ 目的</b>探讨不同阶段多房棘球蚴感染对小鼠淋巴结记忆性T (memory T, Tm) 细胞及其亚群表达水平的影响, 为多房棘球蚴病免疫治疗提供新思路。 <b>方法</b>24只6 ~ 9周龄C57BL/6J小鼠随机分成感染组和对照组, 每组12只; 感染组小鼠经肝门静脉注射3 000 个原头节, 对照组小鼠注射相同体积生理盐水。于感染后第4、12、24周, 每组小鼠分别各随机取3只处死, 取淋巴结组织后采用苏木精-伊红 (hematoxylin and eosin, HE) 染色法观察感染组小鼠淋巴结组织病理变化。通过免疫组织化学染色观察小鼠淋巴结组织中T淋巴细胞表面标志物CD3、CD4和CD8分子表达及定位。提取不同感染时间两组小鼠淋巴结淋巴细胞悬液, 采用流式细胞术检测Tm细胞亚型及其分泌的细胞因子水平。 <b>结果</b>多房棘球蚴感染后4 周, HE染色显示感染组小鼠淋巴结被膜下的皮质和副皮质区域结构呈弥漫性改变。免疫组织化学染色结果显示, 感染组和对照组小鼠淋巴结组织中均有CD3、CD4和CD8分子表达。流式细胞术检测结果显示, 感染后4周, 感染组小鼠淋巴结中CD4 <sup>+</sup> Tm［ (55.3 ± 4.8) % vs. (38.8 ± 6.1) %; <i>t</i> = -4.259, <i>P</i> < 0.05］、CD4 <sup>+</sup> 组织驻留记忆性T (tissue-resident memory T, Trm) 细胞比例［ (57.7 ± 3.7) % vs. (34.1 ± 11.2) %; <i>t</i> = -3.990, <i>P</i> < 0.05］均显著高于对照组; 感染后24周, 感染组小鼠淋巴结中CD4 <sup>+</sup> Tm［ (34.6 ± 3.2) % vs. (23.3 ± 7.5) %; <i>t</i> = -2.764, <i>P</i> < 0.05］、CD4 <sup>+</sup> Trm细胞比例［ (44.0 ± 1.9) % vs. (31.2 ± 1.5) %; <i>t</i> = -4.039, <i>P</i> < 0.05］亦显著高于对照组。感染后4 周［ (56.8 ± 2.7) % vs. (43.9 ± 5.2) %; <i>t</i> = -4.416, <i>P</i> < 0.01］和12 周［ (25.4 ± 2.7) % vs. (12.0 ± 2.6) %; <i>t</i> = -2.552, <i>P</i> < 0.05］, 感染组小鼠淋巴结中CD8 <sup>+</sup> Tm细胞比例均显著高于对照组; 感染后24 周, 感染组小鼠淋巴结中肿瘤坏死因子 (tumor necrosis factor, TNF) -α <sup>+</sup> CD4 <sup>+</sup> T［ (15.7 ± 5.0) % vs. (49.4 ± 6.4) %; <i>t</i> = 7.150, <i>P</i> < 0.01］、TNF-α <sup>+</sup> CD8 <sup>+</sup> T细胞比例［ (20.7 ± 5.5) % vs. (57.5 ± 8.4) %; <i>t</i> = -6.694, <i>P</i> < 0.01］和TNF-α <sup>+</sup>CD8 <sup>+</sup> Tm细胞比例［7.0% (1.0%) vs. 31.0% (11.0%); <i>Z</i> = -2.236, <i>P</i> < 0.05］均显著低于对照组。 <b>结论</b>多房棘球蚴感染不同阶段小鼠淋巴结组织中Tm细胞均增加, 以Trm细胞增加为主; 晚期感染阶段, 小鼠淋巴结组织中CD8 <sup>+</sup> Tm细胞分泌效应分子TNF-α能力减弱, 可能有助于多房棘球蚴慢性寄生。 </p>

ScienceOpen
ScienceOpenMay 28, 2025
The Chinese Journal of Schistosomiasis Control is a leading scientific journal for advancing the #Research and practice in the field of #Schistosomiasis and other #ParasiticDiseases and their control in China: https://www.scienceopen.com/collection/ChinJSchistoControl
Chinese Journal of Schistosomiasis Control

<p><em>Chinese Journal of Schistosomiasis Control </em>is a leading scientific journal for advancing the research and practice in the field of schistosomiasis and other parasitic diseases and their control in China. It is a professional journal to report on the developments and the latest trends related to schistosomiasis and other parasitic diseases across the world.</p>

ScienceOpen
BUKO Pharma-KampagneJan 8, 2025
Kennt ihr schon unsere #Podcast-Reihe zu #NTDs? Hört spannende Geschichten zu #Chagas, #Schistosomiasis, #Tollwut, #Schlangenbissen und zum #Trachom 👇
https://www.youtube.com/playlist?list=PLxgSnvr1t0xClIy6YGDO14swqCMnEK5h4
Vernachlässigte Tropenkrankheiten (NTDs)

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RIO JournalApr 8, 2024

❓Can we confirm resistance to a drug used for the past 30+ years against #Schistosomiasis: a neglected tropical #disease affecting >200 million people (45% children)?

🇬🇭#Researchers from Ghana share their Research Idea in our journal: https://doi.org/10.3897/rio.10.e120899 #WorldHealthDay

Development of a field diagnostic tool for Schistosoma mansoni Praziquantel resistant markers in selected endemic communities

Schistosomiasis is a neglected tropical disease that affects more than 200 million people and 45% of infections have been shown to occur in school-aged children. A large percentage of the disease burden lies in Africa. In 2012, the WHO outlined a roadmap for the elimination of schistosomiasis by 2020; however, this was not achieved. Treatment for schistosomiasis is by the use of Praziquantel, a drug in use for over 30 years and there is a concern for emerging drug resistance. There are several species of the genus Schistosoma causing infection in humans. For this study, Schistosoma mansoni which causes intestinal schistosomiasis will be investigated. There are reports of lowering cure rates and suboptimal response to praziquantel following several cycles of mass drug administration (MDA). Praziquantel resistance has also been reported in some countries and laboratory-bred schistosome experiments. To address the concerns of resistance, this study aims to employ a two-part approach to assess the prevalence of S. mansoni. praziquantel resistance amongst school-aged children in schistosomiasis endemic communities in Ghana and develop a diagnostic tool to aid in field assessment of infections. To achieve this, the study will attempt to answer the following research questions: 1. Is there developing S. mansoni praziquantel resistance in communities that have undergone several mass drug administrations? 2. Is there an interplay between intermediate host exposure to praziquantel and the development of praziquantel drug resistance in the definitive host?

Research Ideas and Outcomes
Matt WillemsenApr 8, 2024
Radical Vaccine Strategy Could Help Quash Parasite Afflicting Millions
https://www.sciencealert.com/radical-vaccine-strategy-could-help-quash-parasite-afflicting-millions #health #disease #parasites #schistosomiasis #vaccine #PhageDisplay
Radical Vaccine Strategy Could Help Quash Parasite Afflicting Millions

Using viruses that infect bacteria to detect proteins sprouted by a notorious parasite, scientists have honed in on possible vaccine targets for schistosomiasis, a neglected tropical disease that currently affects an estimated 600 million people worldwide,

ScienceAlert
BUKO Pharma-KampagneMar 20, 2024
Noch vor Ostern werden wir Euch die dritte Podcast Folge zu #NTDs präsentieren, dieses Mal geht´s um #Tollwut. Seid gespannt🥳
Bis dahin hört doch mal in unsere bisherigen Folgen zu #Chagas und #Schistosomiasis rein⏯️🎧🎈👇
https://tinyurl.com/yl7l35gw
Vernachlässigte Tropenkrankheiten (NTDs) im Fokus: Chagas

YouTube
BUKO Pharma-KampagneJan 30, 2024
Dem Thema #Schistosomiasis widmet sich auch unsere neue Podcastfolge! 🎧
Mit dabei: Daniela Fusco, die am BNITM eine Arbeitsgruppe in der Abteilung für #Infektionsepidemiologie leitet und unter anderem Projekte auf #Madagaskar durchführt.
Wir freuen uns, wenn Ihr reinhört! ⬇️
https://www.youtube.com/watch?v=fwcRq4lpBqY
Vernachlässigte Tropenkrankheiten (NTDs) im Fokus: Schistosomiasis

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Jacob TennessenNov 3, 2023
New preprint! Proud to be part of this important study on the #genome of an African #snail vector that transmits #parasites causing #schistosomiasis, one of the most prevalent #NeglectedTropicalDiseases affecting >200 million people. I know, you've seen genome papers before, but wait there's more! We actually sequenced several inbred lines, allowing us to find and characterize highly variable genes of possible immune relevance.
🐌🧬🐌🧬🐌🧬🐌🧬🐌🧬
https://www.biorxiv.org/content/10.1101/2023.11.01.565203v1