Microbial symbionts are increasingly recognized as promising tools for the biological control of mosquito vectors. Chromobacterium anophelis, an entomopathogenic bacterium isolated from malaria mosquitoes, has demonstrated both larvicidal and adulticidal effects under laboratory conditions. However, its influence on mosquito reproductive behavior and survival under semi-field conditions remains insufficiently explored. We evaluated the effects of C. anophelis and its cell-free supernatant (Sup) on Anopheles coluzzii using a semi-field experimental design. Mosquitoes were exposed to varying concentrations of bacterial suspensions (Ca) or supernatant through sugar feeding. Survival probability was monitored daily for 14 days. Behavioral and reproductive parameters including swarm size, number of mating couples, and insemination rate were recorded during dusk swarming events. Statistical analyses included Kaplan–Meier survival estimates, analysis of variance (ANOVA), and behavioral comparisons across seven treatment groups. Exposure to both Ca and Sup significantly reduced mosquito survival, with complete mortality observed within 10 days in the highest-dose treatment groups. Swarm size was markedly reduced in Ca_10p6 and Sup_30
New World screwworm (NWS), caused by the dipteran Cochliomyia hominivorax, remains a major challenge in Neotropical regions, causing extensive tissue damage and predisposing affected hosts to secondary infections in both humans and animals. Although traditional management has relied on labor-intensive topical treatments, systemic therapies based on isoxazolines offer a more practical alternative. This multicenter clinical study evaluated the therapeutic efficacy of a single oral administration of fluralaner (Bravecto®) in dogs naturally infested with C. hominivorax in endemic regions of Brazil. Fifteen client-owned dogs with natural NWS infestations of varying severity were treated with fluralaner chewable tablets at the approved dose range (25–56 mg/kg). Clinical evaluations were performed 24 h after administration. Wounds were examined, and all larvae, whether expelled or still present within the lesions, were collected, counted, and classified according to motility. Live third-instar (L3) larvae expelled after treatment were transferred to pupation substrates and maintained under controlled laboratory conditions to assess adult emergence. Treatment achieved 100
The immunogenicity of promastigote surface antigens (PSA) derived from Leishmania spp. has been well-documented and the efficacy of various vaccine platforms, including virus-like particles (VLPs) that express this antigen has been explored. However, many PSA-expressing vaccine studies involved homologous challenge infection and cross-species protection elicited by PSA-expressing leishmaniasis vaccines remains largely unexplored. To address this gap in our understanding, we evaluated the cross-protective efficacy of VLP vaccines expressing the L. amazonensis PSA (LaPSA-VLP) against L. donovani infection in mice. Influenza VLPs expressing the PSA of L. amazonensis were self-assembled in Spodoptera frugiperda insect cells. The VLPs were characterized by SDS-PAGE, western blotting, and transmission electron microscopy to confirm successful assembly and antigen expression. L. amazonensis parasites expressing mCherry fluorescence were cultured, and the peak growth time point was selected. To evaluate heterologous protection, mice were immunized three times at 3-week intervals, and blood was collected 1 week after each immunization. Three weeks after the final immunization, mice were challenge-infected and killed 2 weeks post-infection for sample collection. Antibody responses, immune cell analysis, cytokine production measurement, and parasite burden were assessed. Nucleotide and amino acid sequences for the PSA of L. amazonensis and L. donovani were highly similar, signifying that cross-reactivity between the two species can occur. Intramuscular LaPSA-VLP immunization elicited cross-reactive IgG antibody production that reacted with L. donovani antigens. Compared to the unimmunized controls, LaPSA-VLP vaccines enabled the induction of germinal center B cells and CD4+/CD8+ T cells. VLP vaccines significantly reduced hepatic inflammation by limiting IFN-γ and IL-6 cytokine production. LaPSA-VLP immunization drastically reduced the parasite burden in the visceral organs, implying that the PSA antigen derived from L. amazonensis can confer cross-protection against L. donovani infection.
The Anopheles maculipennis complex comprises closely related mosquito species of epidemiological importance across the Palearctic region. Anopheles messeae and Anopheles daciae are among its most widely distributed members but are morphologically indistinguishable, hindering species-specific vector surveillance and ecological and epidemiological studies. This limitation highlights the need for rapid, sensitive, specific, and high-throughput molecular methods for their identification. We report the development and validation of a TaqMan SNP genotyping assay targeting the Internal Transcribed Spacer 2 (ITS2) locus to discriminate between two closely related members of the Anopheles maculipennis complex, An. messeae and An. daciae. The assay targets a diagnostic single-nucleotide polymorphism (SNP) within the ITS2 region of ribosomal DNA. The optimized TaqMan SNP genotyping assay was applied to 293 field-collected mosquitoes. The assay showed high analytical sensitivity, with a detection limit of 0.1 ng of genomic DNA, and high specificity, with no false-positive results among the non-target species tested. The TaqMan assay showed 98
Myocardial ischemia–reperfusion (IR) injury is a critical complication in patients with myocardial infarction following the restoration of coronary blood flow. Echinococcus granulosus cyst fluid protein antigen B (EgAgB) is known to modulate host immune response. This study investigates whether the recombinant antigen B subunit 2 (rEgAgB8/2) can mitigate IR injury by suppressing inflammation and promoting myocardial tissue repair. An IR injury model was induced by ligating the left anterior descending (LAD) coronary artery for 1 h, followed by 24 h reperfusion. Recombinant EgAgB8/2 protein expressed in E. coli was administered intraperitoneally at the onset of reperfusion to evaluate its therapeutic potential. After 24 h of reperfusion, cardiac function and injury were assessed using echocardiography, TTC/Evans Blue staining, and histopathological analysis. Protein and mRNA levels of cytokines (TNF-α, IL-6, IL-10, and TGF-β) in sera and cardiac tissue were quantified using ELISA and RT-qPCR, respectively. In vitro studies, cytokine secretion in bone marrow-derived macrophages (BMDMs) culture supernatants was measured by ELISA. Macrophage polarization was evaluated via flow cytometry by identifying surface markers for M1 (CD86⁺) and M2 (CD206⁺) phenotypes. Expression levels of proteins in the cGAS/STING/p-TBK1/p-IRF3 signaling pathway in both myocardial tissues and BMDMs were detected by Western blotting. Treatment with rEgAgB8/2 significantly improved cardiac function and reduced myocardial injury markers (LDH, CK-MB) and infarct size in mice with IR injury. Compared to untreated IR controls, rEgAgB8/2 treatment significantly reduced the levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) in both serum and cardiac tissue, and downregulated the M1 macrophage marker iNOS in cardiac tissue. Concurrently, it increased the expression of anti-inflammatory cytokines (IL-10 and TGF-β) in serum and cardiac tissue, along with upregulating the M2 macrophage marker Arg-1 in cardiac tissue. This reduction in the inflammatory response in IR-injured cardiac tissue was associated with enhanced polarization toward the M2 macrophage phenotype. In vitro studies further showed that rEgAgB8/2 promotes M2 macrophage polarization associated with reduced activation of the cGAS/STING/TBK1/IRF3 signaling pathway. rEgAgB8/2 promotes macrophage polarization toward M2 phenotype in a manner associated with suppression of the cGAS/STING/TBK1/IRF3 signaling pathway to attenuate myocardial IR injury and associated inflammation. It provides a novel therapeutic strategy for ischemia–reperfusion injury and related inflammatory diseases.
