Po-Ching Cheng

Background: Angiostrongylus cantonensis (rat lungworm) infection causes neuroangiostrongyliasis, a parasitic disease characterized by eosinophilic meningitis and meningoencephalitis. Within the central nervous system (CNS), larval migration and degeneration provoke neuroinflammation involving microglia and astrocytes. Albendazole (ABZ) is the mainstay treatment but may exacerbate inflammation through antigen release from dying worms. Doxycycline (DOX), a tetracycline antibiotic with anti-inflammatory and neuroprotective properties, can attenuate glial activation and matrix metalloproteinase activity. As a follow-up to our previous work on ABZ–DOX treatment outcomes, this study evaluated whether ABZ–DOX co-therapy (co) provides antiparasitic and neuroprotective benefits associated with interleukin (IL)-33/glial fibrillary acidic protein (GFAP) regulation in A. cantonensis -infected mice. Methods: A laboratory-maintained Taiwan strain of A. cantonensis was used to infect 7–8-week-old C57BL/6 and BALB/c mice (50 third-stage larvae/mouse). For terminal analyses (histopathology, western blotting, and enzyme-linked immunosorbent assay [ELISA]), animals were allocated to eight groups: uninfected control, infected untreated, early ABZ (7–21 days post infection [dpi]), late ABZ (14–21 dpi), early DOX (7–21 dpi), late DOX (14–21 dpi), early ABZ–DOX co-therapy (co; 7–21 dpi), and late co-therapy (co; 14–21 dpi); all were euthanized at 21 dpi. Parasite recovery was performed in an independent cohort following the early-treatment schedule. Magnetic resonance imaging (MRI; 7.0 T) was conducted in a separate longitudinal BALB/c cohort (infected untreated versus early co) scanned up to 28 dpi. Statistical analyses were conducted using t -tests. Results: In an independent cohort treated using the early schedule (7–21 dpi), ABZ-containing regimens reduced worm recovery to near-zero levels in both strains. Histopathology showed eosinophilic meningitis, perivascular inflammation, and hemorrhagic changes in infected brains; these lesions were reduced in treated groups, with the most consistent improvements observed in the early co-therapy group relative to infected untreated controls. In a separate longitudinal MRI cohort (BALB/c; infected untreated versus early co-therapy), T2-weighted images demonstrated reduced hyperintensity and edema-like signal changes after early co-therapy. Western blot analyses indicated infection-associated GFAP upregulation and IL-33 alterations across brain regions, whereas co-therapy shifted these markers toward uninfected levels in a region- and strain-specific manner. Serological ELISA showed increased A. cantonensis -specific immunoglobulin (Ig)A/G/M reactivity in infected mice, which was reduced in treated groups. Conclusions: ABZ–DOX co-therapy was associated with reduced parasite recovery and multilevel improvements across pathology, MRI, and glial markers in mice neuroangiostrongyliasis. These findings support ABZ–DOX co-therapy as a candidate regimen for further investigation in the management of A. cantonensis -associated neuroinflammation. Graphical

Schistosoma mansoni infection leads to chronic schistosomiasis and severe hepatic fibrosis. We designed a liver-targeted lipid nanoparticle (LNP) carrying siRNA against type I TGF-β receptor (TGFβRI) mRNA to treat schistosomiasis-induced liver fibrosis in BALB/c mice. Knockdown of TGFβRI by LNP-siTGFβRI reduced LX-2 cell activation in vitro and alleviated liver fibrosis in S. mansoni-infected mice. αSMA and Col1a1 fibrotic markers in the liver tissues of infected mice were significantly suppressed in the treatment groups. In the serum of the LNP-siTGFβRI-treated groups, cytokines IFNγ, IL-1α, IL-6, IL-12, RANTES (CCL5), and TNFα increased, while GM-CSF, IL-2, IL-4, IL-10, IL-13, and KC (CXCL1) decreased compared to the control. Cell proportions were significantly altered in S. mansoni-infected mice, with increased CD56d NK cells and decreased CD19⁺ B cells and CD4⁺ T cells compared to naïve mice. Following LNP-siTGFβRI treatment, CD56d NK cells were downregulated, while B and memory Th cell populations were upregulated. The density of fibrotic regions significantly decreased with LNP-siTGFβRI treatment in a dose-dependent manner, and no systemic toxicity was observed in the major organs. This targeted siRNA delivery strategy effectively reduced granulomatous lesions in schistosomiasis-induced liver fibrosis without detectable side effects.

Background: Angiostrongylus cantonensis is a parasite that mainly infects the heart and pulmonary arteries of rats and causes human eosinophilic meningitis or meningoencephalitis in certain geographical areas. Current diagnostic methods include detection of the parasite in cerebrospinal fluid (CSF) and eosinophilic immune examination after lumbar puncture, which may be risky and produce false-positive results. ¹⁸F- Fluorodeoxyglucose (FDG), a Positron emission tomography (PET) tracer, has been used to assess different pathological or inflammatory changes in the brains of patients. In this study, we hypothesized that A. cantonensis infection-induced inflammatory and immunomodulatory factors of eosinophils result in localized pathological changes in the brains of non-permissive hosts, which could be analyzed using in vivo ¹⁸F-FDG PET imaging. Methodology/Findings: Non-permissive host ICR mice and permissive host SD rats were infected with A. cantonensis, and the effects of the resulting inflammation on ¹⁸F-FDG uptake were characterized using PET imaging. We also quantitatively measured the distributed uptake values of different brain regions to build an evaluated imaging model of localized neuropathological damage caused by eosinophilic inflammation. Our results showed that the uptake of ¹⁸F-FDG increased in the cerebellum, brainstem, and limbic system of mice at three weeks post-infection, whereas the uptake in the rat brain was not significant. Immunohistochemical staining and western blotting revealed that Iba-1, a microglia-specific marker, significantly increased in the hippocampus and its surrounding area in mice after three weeks of infection, and then became pronounced after four weeks of infection; while YM-1, an eosinophilic chemotactic factor, in the hippocampus and midbrain, increased significantly from two weeks post-infection, sharply escalated after three weeks of infection, and peaked after four weeks of infection. Cytometric bead array (CBA) analysis revealed that the expression of TNF in the serum of mice increased concomitantly with the prolongation of infection duration. Furthermore, IFN-γ and IL-4 in rat serum were significantly higher than in mouse serum at two weeks post-infection, indicating significantly different immune responses in the brains of rats and mice. We suggest that ¹⁸F-FDG uptake in the host brain may be attributed to the accumulation of large numbers of immune cells, especially the metabolic burst of activated eosinophils, which are attracted to and induced by activated microglia in the brain. Conclusions: An in vivo ¹⁸F-FDG/PET imaging model can be used to evaluate live neuroinflammatory pathological changes in the brains of A. cantonensis-infected mice and rats.

Background: The FimH expression may be a key factor affecting prostatitis caused by UPEC infection. Whether its regulation by the JAK/STAT pathway increases resistance to inflammation caused by infection with high FimH-expressing UPEC strains requires investigation. Methods: The effect of FimH on the ability of knockout ΔFimH UPEC, FimH^over -expressed UPEC, and wild-type strains to invade prostate cells and induce inflammation and the effects of different FimH levels on testosterone-treated UPEC and regulation of the JAK/STAT pathway were analyzed. Results: Comparison of the three strains revealed the inhibitory effects of testosterone were more significant in the ΔFimH strain. Testosterone-pretreated ΔFimH UPEC showed weak inflammatory responses and JAK/STAT expression. FimH^over UPEC better resisted the inhibitory effects of testosterone, which there was no significantly decreases except 20 μg/ml pretreated group in most JAK/STAT-related proteins. The effects of FimH showed a concentration-dependent response to testosterone, particularly to JAK1, STAT3, and pSTAT3, which also affected the subsequent expression of TLR4, IL-6, and IFN-γ. It has been suggested that regulation of the JAK1/STAT3 pathway may be associated with the effects of the FimH virulence factor on the inhibition of testosterone in UPEC infection. Conclusion: The inhibitory effect of testosterone on UPEC infection in prostate epithelial cells was affected by the virulence factor FimH of UPEC, and reduced the production of inflammatory factors. The JAK/STAT pathway plays a key role in regulating UPEC infection and influences testosterone suppression responses in prostate cells. Our study provides a possible guideline for using testosterone to treat clinical recurrent UPEC infection and persistent prostatitis.

Schistosomiasis is a major global health problem. Schistosomes secrete antigens into the host tissue that bind to chemokines or inhibit immune cell receptors, regulating the immune responses to allow schistosome development. However, the detailed mechanism of chronic schistosome infection-induced liver fibrosis, including the relationship between secreted soluble egg antigen (SEA) and hepatic stellate cell (HSC) activation, is still unknown. We used mass spectrometry to identify the SEA protein sequences from different infection weeks. In the 10th and 12th infection weeks, we focused on the SEA components and screened out the special protein components, particularly fibrosis- and inflammation-related protein sequences. Our results have identified heat shock proteins, phosphorylation-associated enzymes, or kinases, such as Sm16, GSTA3, GPCRs, EF1-α, MMP7, and other proteins linked to schistosome-induced liver fibrosis. After sorting, we found many special proteins related to fibrosis and inflammation, but studies proving their association with schistosomiasis infection are limited. Follow-up studies on MICOS, MATE1, 14-3-3 epsilon, and CDCP1 are needed. We treated the LX-2 cells with the SEA from the 8th, 10th, and 12th infection weeks to test HSC activation. In a trans-well cell model in which PBMCs and HSCs were co-cultured, the SEA could significantly induce TGF-β secretion, especially from the 12th week of infection. Our data also showed that TGF-β secreted by PBMC after the SEA treatment activates LX-2 and upregulates hepatic fibrotic markers α-SMA and collagen 1. Based on these results, the CUB domain-containing protein 1 (CDCP1) screened at the 12th infection week could be investigated further. This study clarifies the trend of immune mechanism variation in the different stages of schistosome infection. However, how egg-induced immune response transformation causes liver tissue fibrosis needs to be studied further.

JAK/STAT plays a key role in regulating uropathogenic Escherichia coli (UPEC) infection in urothelial cells, probably via antimicrobial peptide (AMP) production, in diabetic patients with urinary tract infections. Whether multiple pathways regulate AMPs, especially lipid-carrying protein-2 (LCN2), to achieve a vital effect is unknown. We investigated the effects of an LCN2 pretreatment on the regulation of the JAK/STAT pathway in a high-glucose environment using a bladder cell model with GFP-UPEC and phycoerythrin-labeled TLR-4, STAT1, and STAT3. Pretreatment with 5 or 25 μg/mL LCN2 for 24 h dose-dependently suppressed UPEC infections in bladder cells. TLR-4, STAT1, and STAT3 expression were dose-dependently downregulated after LCN2 pretreatment. The LCN2-mediated alleviation of UPEC infection in a high-glucose environment downregulated TLR-4 and the JAK/STAT transduction pathway and decreased the UPEC-induced secretion of exogenous inflammatory interleukin (IL)-6 and IL-8. Our study provides evidence that LCN2 can alleviate UPEC infection in bladder epithelial cells by decreasing JAK/STAT pathway activation in a high-glucose environment. LCN2 dose-dependently inhibits UPEC infection via TLR-4 expression and JAK/STAT pathway modulation. These findings may provide a rationale for targeting LCN2/TLR-4/JAK/STAT regulation in bacterial cystitis treatment. Further studies should explore specific mechanisms by which the LCN2, TLR-4, and JAK/STAT pathways participate in UPEC-induced inflammation to facilitate the development of effective therapies for cystitis.

Background: Aedes aegypti and Aedes albopictus are two important vectors of several important arboviruses, including the dengue, chikungunya, and Zika viruses. Insecticide application is an important approach to reduce vector abundance during Aedes spp.-borne outbreaks in the absence of effective vaccines and treatments. However, insecticide overuse can result in the development of resistance, and careful monitoring of resistance markers is required. Methods: This meta-analysis and systematic review explored the spatial and temporal patterns of insecticide resistance in Asia from 2000 to 2021. PubMed, Scopus, EbscoHost, and Embase were used to enhance the search capability. The random-effects model was applied for the 94 studies that met our inclusion criteria for qualitative synthesis and meta-analysis. Results: Four major insecticides were studied (malathion, dichlorodiphenyltrichloroethane, permethrin, and deltamethrin). Dichlorodiphenyltrichloroethane resistance rates were high in both Ae. aegypti and Ae. albopictus (68% and 64%, respectively). Conversely, malathion resistance was less prevalent in Ae. aegypti (3%), and deltamethrin resistance was less common in Ae. albopictus (2%). Ae. aegypti displayed consistently high resistance rates (35%) throughout the study period, whereas the rate of insecticide resistance in Ae. albopictus increased from 5% to 12%. The rates of the major kdr mutations F1534C, V1016G, and S989P were 29%, 26%, and 22%, respectively. Conclusions: Insecticide resistance in both Ae. aegypti and Ae. albopictus is widespread in Asia, although the rates vary by country. Continuous monitoring of the resistance markers and modification of the control strategies will be important for preventing unexpected outbreaks. This systematic review and meta-analysis provided up-to-date information on insecticide resistance in dengue-endemic countries in Asia.