中国血吸虫病防治杂志最新文献

Malaria, a parasitic disease caused by infection with the species of Plasmodium and transmitted by Anopheles mosquito bites, is one of the major public health challenges that seriously threaten human health. Malaria parasites present diverse immune escape strategies to escape from the recognition and clearance of the host immune system, which poses a great challenge to the malaria control programme. This review presents the advances in the mechanisms underlying the immune escape of Plasmodium, including antigenic variation, epigenetic regulation, antagonism against IgM antibody, activation of the cyclic guanosine monophosphate-adenosine monophosphate (GMP-AMP) synthase-stimulator of interferon genes (cGAS-STING) signaling, suppression of splenic immune functions, and molecular camouflage, so as to provide insights into development of malaria vaccines and antimalarial agents and formulation of the malaria control strategy.

Objective: To investigate the genetic diversity of sandfly populations in endemic areas of visceral leishmaniasis in China, so as to provide references insights into management of visceral leishmaniasis and the vector sandflies.

Methods: Sixteen sampling sites were selected from main endemic foci of visceral leishmaniasis in China from June to September 2024, including Shanxi Province, Shaanxi Province, Henan Province, Gansu Province, Sichuan Province, and Xinjiang Uygur Autonomous Region. Sandflies were captured using light traps and manual aspirators from sheep pens, chicken coops, cave dwellings, bovinesheds, and pig pens at each sampling site. A single sandfly sample was washed in phosphate-buffered saline (PBS), and genomic DNA was extracted from sandfly samples. Cytochrome oxidase subunit 1 (COI) gene was amplified using PCR assay with universal primers, and analyzed and retrieved with the nucleotide sequence analysis tool (BLAST) software, and the sequence of COI gene was aligned with the ClustalX 1.83 and MEGA 7.0 software. The base composition and variation site of the COI gene sequence were analyzed using the software MEGA 7.0, and the number of haplotypes, total number of segregating sites, haplotype diversity, nucleotide diversity, and average nucleotide differences were calculated in the COI gene sequence using the software DnaSP 5.10, followed by Tajima's D test for neutrality. Haplotypes were screened using the software DnaSP 5.10, and the haplotype network map of sandfly samples was plotted using the software Network 5.0. MEGA 7.0 software was employed for gene sequence editing and alignment, and calculation of genetic distances among sandfly species sampled from different regions, and a phylogenetic tree was built with a neighbor-joining method.

Results: A total of 466 sandflies were captured from 16 sampling sites in China from June to September 2024, and 430 gene sequences were yielded following PCR amplification and sequencing of the COI gene, with 652 to 688 bp in the length of amplification fragments. The captured sandfly samples were characterized as Phlebotomus chinensis, Sergentomyia squamirostris, Se. koloshanensis, Ph. sichuanensis, and Ph. longiductus following the COI gene sequence alignment in BLAST. A total of 251 haplotypes were identified in the 430 gene sequences from sandfly samples (50.5%), and the average haplotype diversity, nucleotide diversity and average number of nucleotide difference were 0.885, 0.257 and 160.761, respectively. The Tajima's D values were -0.92 for sandfly populations from Yangquan City, Shanxi Province and -1.73 for sandfly populations from Sanmenxia City, Henan Province, and were all more than 0 for sandfly populations from other sampling sites. Haplotype analysis identified 50 haplotypes, which were classified into two haplogroups.

Objective: To investigate the effects of Echinococcus multilocularis 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.

Methods: 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 E. multilocularis 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.

Results: 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 E. multilocularis. Immunohistochemical staining detected CD3, CD4 and CD8 expression in mouse lymph nodes in both groups. Flow cytometry revealed higher proportions of CD4⁺ Tm cells [(55.3 ± 4.8)% vs. (38.8 ± 6.1)%; t = -4.259, P < 0.05] and CD4⁺ tissue-resident Tm (Trm) cells [(57.7 ± 3.7)% vs. (34.1 ± 11.2)%; t = -3.990, P < 0.05] in mouse lymph nodes in the infection group than in the control group 4 weeks post-infection, and higher proportions of CD4⁺ Tm cells [(34.6 ± 3.2)% vs. (23.3 ± 7.5)%; t = -2.764, P < 0.05] and CD4⁺ Trm cells [(44.0 ± 1.9)% vs. (31.2 ± 1.5)%; t = -4.039, P < 0.05] in mouse lymph nodes in the infection group than in the control group 24 weeks post-infection. The proportions of CD8⁺ Tm cells were higher in the infection group than in the control group 4 weeks [(56.8 ± 2.7)% vs. (43.9 ± 5.2)%; t = -4.416, P < 0.01] and 12 weeks post-infection [(25.4 ± 2.7)% vs. (12.0 ± 2.6)%; t = -2.552, P < 0.05], while the proportions of tumor necrosis factor (TNF)-α⁺ CD4⁺ T cells [(15.7 ± 5.0)% vs. (49.4 ± 6.4)%; t = 7.150, P < 0.01], TNF-α⁺CD8⁺ T cells [(20.7 ± 5.5)% vs. (57.5 ± 8.4)%; t = -6.694, P < 0.01], and TNF-α⁺ CD8⁺ Tm cells [7.0% (1.0%) vs. 31.0% (11.0%); Z = -2.236, P < 0.05] were l

Objective: To analyze the structural and phylogenetic characteristics of the mitochondrial genome from Bulinus globosus, so as to provide a theoretical basis for classification and identification of species within the Bulinus genus, and to provide insights into understanding of Bulinus-schistosomes interactions and the mechanisms of parasite transmission.

Methods: B. globosus samples were collected from the Ruya River basin in Zimbabwe. Mitochondrial DNA was extracted from B. globosus samples and the corresponding libraries were constructed for high-throughput sequencing on the Illumina NovaSeq 6000 platform. After raw sequencing data were subjected to quality control using the fastp software, genome assembly was performed using the A5-miseq and SPAdes tools, and genome annotation was conducted using the MITOS online server. Circular maps and sequence plots of the mitochondrial genome were generated using the CGView and OGDRAW software, and the protein conservation motifs and structures were analyzed using the TBtools software. Base composition and codon usage bias were analyzed and visualized using the software MEGA X and the ggplot2 package in the R software. In addition, a phylogenetic tree was created in the software MEGA X after sequence alignment with the software MAFFT 7, and visualized using the software iTOL.

Results: The mitochondrial genome of B. globosus was a 13 730 bp double-stranded circular molecule, containing 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 13 protein-coding genes, with a marked AT preference. The mitochondrial genome composition of B. globosus was similar to that of other species within the Bulinus genus. Phylogenetic analysis revealed that the complete mitochondrial genome sequence of B. globosus was clustered with B. truncatus, B. nasutus, and B. ugandae into the same evolutionary clade, and gene superfamily analysis showed that the metabolism-related proteins of B. globosus were highly conserved, notably the cytochrome c oxidase family, which showed a significant consistency.

Conclusions: This is the first whole mitochondrial genome sequencing to decode the compositional features of the mitochondrial genome of B. globosus from Zimbabwe and its evolutionary relationship within the Bulinus genus, which provides important insights for further understanding of the phylogeny and mitochondrial genome characteristics of the Bulinus genus.

Objective: To clone and express the heat shock cognate protein 20 (SjHsc20) of Schistosoma japonicum, and to preliminarily investigate its biological characteristics.

Methods: The target fragment of the SjHsc20 gene was amplified using PCR assay and cloned into the pET-28a(+) expression plasmid to generate the recombinant expression vector pET-28a(+)-SjH-sc20, which was then transformed into Escherichia coli BL21 (DE3) competent cells. The recombinant SjHsc20 (rSjHsc20) protein was induced with isopropyl β-D-thiogalactopyranoside (IPTG) and purified, and the expression of the rSjHsc20 protein was checked with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The immunogenicity of the rSjHsc20 protein was detected using Western blotting, and the transcriptional levels of SjHsc20 were quantified in S. japonicum worms at different developmental stages and in male and female adult worms using real-time quantitative PCR (RT-qPCR) assay. Thirty female BALB/c mice at ages 6 to 8 weeks were divided into three groups, including the rSjHsc20 immunization group, the PBS control group, and the ISA 206 adjuvant group, of 10 mice in each group. Mice in the rSjHsc20 immunization group were subcutaneously immunized with 20 μg rSjHsc20 on days 1, 15 and 31, and animals in the PBS control group were subcutaneously injected with the same volume of PBS on days 1, 15 and 31, while mice in the ISA 206 adjuvant group were subcutaneously immunized with the same volume of ISA 206 adjuvant on days 1, 15 and 31, respectively. All mice in each group were infected with (40 ± 2) S. japonicum cercariae via the abdomen 14 day following the last immunization. Levels of serum specific IgG and its subtypes IgG1 and IgG2 antibodies against rSjHsc20, and the serum titers of anti-rSjHsc20 antibody were detected in mice using indirect enzyme-linked immunosorbent assay (ELISA). All mice were sacrifice 42 days post-infection, and S. japonicum worms were collected from the hepatic portal vein and counted. The eggs per gram (EPG), worm burden reductions and egg burden reductions were estimated to evaluate the protective efficacy of the rSjHsc20 protein.

Results: The SjHsc20 gene had an open reading frame (ORF) with 756 bp in length and encoded 252 amino acids, and the rSjHsc20 protein had a relative molecular mass of approximately 29 kDa. The rSjHsc20 protein was recognized by the serum of mice infected with S. japonicum and the serum of mice immunized with the rSjHsc20 protein, indicating that rSjHsc20 had a good immunogenicity. There was a significant difference in the transcriptional levels of the SjHsc20 gene among the 7-day (1.001 4 ± 0.065 7), 12-day (2.268 3 ± 0.129 2), 21-day (1.378 5 ± 0.160 4), 28-day (1.196 4 ± 0.244 0), 35-day (1.646 3 ± 0.226 1), 42-day worms of S. japonicum (1.758 0 ± 0.611 1) (F = 38.45, P

The rapid rise and fast development of artificial intelligence (AI) has brought unprecedented opportunities and challenges to all sectors, including disease prevention control. Malaria is one of the world's most devastating infectious diseases. This article summarizes the advances in the research and application of AI-empowered malaria control programmes, analyzes key challenges during the implementation of malaria control programmes, and proposes future development directions and research proprieties, so as to provide insights into facilitating the translation of AI-driven strategies in global infectious disease control efforts.

Elimination of malaria is one of important global public health targets. Malaria was once highly prevalent in China; however, China was certified malaria-free by WHO in 2021 following decades of integrated control efforts. As an effective intervention, health education plays a critical role during the progress towards elimination of malaria in China, which remarkably increases the public awareness and action capability of malaria prevention and control knowledge. In addition, health education is of great significance to reduce the risk of re-establishment of imported malaria following disease elimination in the country. This article reviews the application of community-based and school-based health education, health education activities targeting entry-exit personnel and healthcare workers, and diversified media propagation in the progress towards elimination of malaria in China, so as to provide insights into formulation of malaria control strategy during the post-elimination stage in the country.