Development and evaluation of time-resolved rapid immunofluorescence test for detection of TSOL18 specific antibody in porcine cysticercosis infections.

BACKGROUND: Porcine cysticercosis, a serious zoonotic parasitic disease, is caused by the larvae of Taenia solium and has been acknowledged by the World Organization for Animal Health. The current detection methods of Cysticercus cellulosae cannot meet the needs of large-scale and rapid detection in the field. We hypothesized that the immunofluorescence chromatography test strip (ICS) for detecting Cysticercus cellulosae, according to optimization of a series of reaction systems was conducted, and sensitivity, specificity, and stability testing, and was finally compared with ELISA. This method utilizes Eu3+-labeled time-resolved fluorescent microspheres (TRFM) coupled with TSOL18 antigen to detect TSOL18 antibodies in infected pig sera. RESULTS: ICS and autopsy have highly consistent diagnostic results (n = 133), as determined by Cohen's κ analysis (κ = 0.925). And the results showed that the proposed ICS are high sensitivity (0.9459) with specificity (0.9792). The ICS was unable to detect positive samples of other parasites. It can be stored for at least six months at 4℃. CONCLUSIONS: In summary, we established a TRFM-ICS method with higher sensitivity and specificity than indirect ELISA. Results obtained from serum samples can be read within 10 min, indicating a rapid, user-friendly test suitable for large-scale field detection.

Histopathological and morphological characterization of Cysticercus fasciolaris isolated from domestic and wild rodents in Morocco.

Cysticercus fasciolaris is a parasitic helminth that usually infects feline and canine mammal hosts. The intermediate hosts (rodents, occasionally lagomorphs, and humans) get infected by the consumption of feed or water contaminated with eggs. Rodents are vectors of disease and reservoirs of various zoonotic parasites. The current survey was aimed at determining endoparasitic helminth infections in rodents in central Morocco. Sampled rodents after specific identification were sacrificed and examined to identify parasitic helminths following ethical guidelines. Parasites were identified using morphological characteristics. A total of 197 specimens of rodents were collected and examined in this study. Ten rodent species were identified morphologically as Rattus rattus, R. norvegicus, Apodemus sylvaticus, Mus musculus, M. spretus, Mastomys erythroleucus, Meriones shawi, M. libycus, Gerbillus campestris, and Lemniscomys barbarus. The parasitological results showed that metacestode of tapeworms was found encysted in the liver, the larval stage of Taenia taeniaeformis develops large multinodular fibrosarcomas which envelope the tapeworm cysts in the liver of the R. rattus and R. norvegicus. Based on morphological data, the metacestode was identified as C. fasciolaris in 23 (23/80) R. rattus 2 (2/8) and R. norvegicus with a prevalence of 11.7 % and 1.0 %, respectively. Rodents are major vectors of human and domestic animal diseases worldwide, and therefore, important parasitic zoonotic agents (C. fasciolaris), which are transmitted by black rats (R. rattus) and brown rats (R. norvegicus), must be considered to prevent the infectivity of humans, domestic animals, and livestock such as cattle, sheep, and rabbits.

Global profiling of miRNA and protein expression patterns in rabbit peritoneal macrophages treated with exosomes derived from Taenia pisiformis cysticercus.

Infection of Taenia pisiformis cysticercus is very frequently found in lagomorphs and causes serious economic losses to rabbit breeding industry. T. pisiformis cysticercus has evolved numerous strategies to manipulate their hosts. The release of exosomes is of importance in the interaction between host and parasite. However, the mechanism by which T. pisiformis cysticercus evades the host immune system for long-term survival within the host remains unclear. Using small RNA sequencing and TMT labelling proteomic, we profiled the expression patterns of miRNAs and proteins in rabbit peritoneal macrophages treated with T. pisiformis cysticercus exosomes. Seven differentially expressed (DE)-miRNAs and six DE-proteins were randomly selected to validate the accuracy of the sequencing data by qRT-PCR or western blot. Functions of DE-miRNAs and proteins were analyzed using public data bases. And DE-miRNAs-DE-proteins correlation network were established. CCK-8 assay was used to evaluate the effect of exosomes on macrophages proliferation. Cell cycle of macrophages, isolated from T. pisiformis-infected rabbits, was determined using flow cytometry. A total of 21 miRNAs were significantly differentially expressed, including three worm-derived miRNAs. The expressions of miRNAs and proteins were consistent with the sequencing results. DE-miRNAs targets were related to cell proliferation and apoptosis. Exosomes treatment resulted in a decrease of macrophages proliferation. In vivo, T. pisiformis cysticercus significantly induced S phase cell arrest. Moreover, DE-proteins were related to production of interferon-gamma and interleukin-12, and immunoregulation. Correlation network analysis revealed a negative correlation relationship between DE-miRNAs and DE-proteins. Among them, novel334 and tpi-let-7-5p have potential regulatory effects on IL1ß and NFκB2 respectively, which imply that novel334-IL1ß/tpi-let-7-5p-NFκB2 axis may be an important way that T. pisiformis cysticercus modulates host immune response through exosomes. Further understanding of these potential regulatory mechanisms will contribute to clarify the mechanism of escape mediated by T. pisiformis exosomes.

Effect of Hydroxyurea on Morphology, Proliferation, and Protein Expression on Taenia crassiceps WFU Strain.

Flatworms are known for their remarkable regenerative ability, one which depends on totipotent cells known as germinative cells in cestodes. Depletion of germinative cells with hydroxyurea (HU) affects the regeneration of the parasite. Here, we studied the reduction and recovery of germinative cells in T. crassiceps cysticerci after HU treatment (25 mM and 40 mM of HU for 6 days) through in vitro assays. Viability and morphological changes were evaluated. The recovery of cysticerci's mobility and morphology was evaluated at 3 and 6 days, after 6 days of treatment. The number of proliferative cells was evaluated using EdU. Our results show morphological changes in the size, shape, and number of evaginated cysticerci at the 40 mM dose. The mobility of cysticerci was lower after 6 days of HU treatment at both concentrations. On days 3 and 6 of recovery after 25 mM of HU treatment, a partial recovery of the proliferative cells was observed. Proteomic and Gene Ontology analyses identified modifications in protein groups related to DNA binding, DNA damage, glycolytic enzymes, cytoskeleton, skeletal muscle, and RNA binding.

Potential control of the infective stage of Taenia pisiformis using Bacillus thuringiensis GP526 strain.

The GP526 strain of Bacillus thuringiensis has been referred as an in vitro helminthicide on various stages of Dipylidium caninum and Centrocestus formosanus. Our study addresses the in vitro ovicidal activity of GP526 strain spore-crystal complex on Taenia pisiformis eggs, evaluating induced damage microscopically. The eggs exposed to the total extract containing spores and crystals show damage after 24 hours, with loss of integrity on the eggshell, and an ovicidal activity of 33% at 1mg/ml. The destruction of the embryophore was observed after 120 h with a 72% of ovicidal activity at 1 mg/ml. The LC50 was 609.6 µg/ml, dose that causes a 50% of lethality on the hexacanth embryo, altering the oncosphere membrane. The spore-crystal proteins were extracted, and the protein profile was obtained by electrophoresis, finding a major band of 100 kDa suggestive of an S-layer protein, since an S-layer was immunodetected in both, spores and extracted proteins. The protein fraction containing the S-layer protein presents adhesion to the T. pisiformis eggs, and 0.4 mg/ml of the protein induces a lethality of 21.08% at 24 h. The characterization of molecular mechanisms of ovicidal activity will be an important contribution, so the characterization of the proteins that make up the extract of the GP526 strain, would be useful to support the biological potential for control of this cestodiasis and other parasitosis. B. thuringiensis is shown as a potent helminthicide on eggs, with useful potential for biological control of this cestodiasis.

Albendazole - Ivermectin combination decreases inflammation in experimental neurocysticercosis.

Neurocysticercosis (NCC) is a public health issue in endemic regions and is considered the main preventable cause of neurologic disease. It is caused by the presence of Taenia solium cysticercus in the central nervous system. The current treatment is performed with anthelminthic drugs - albendazole (ABZ) or praziquantel - associated with anti-inflammatory and corticosteroids in order to prevent the negative effects of the inflammatory reaction to the parasite's death. Ivermectin (IVM) is an anthelminthic drug that has been shown to present an anti-inflammatory effect. The aim of this study was to was to evaluate the histopathologic aspects of experimental NCC after in vivo treatment with a combination of ABZ-IVM. Balb/c mice were intracranially inoculated with T. crassiceps cysticerci and after 30 days of infection were treated with a single dose of NaCl 0.9% (control group), ABZ monotherapy (40 mg/kg), IVM monotherapy (0.2 mg/kg) or a combination of ABZ-IVM. 24h after the treatment the animals were euthanized and the brain was removed for histopathologic analysis. The IVM monotherapy and ABZ-IVM combination showed more degenerated cysticerci, less inflammatory infiltration, meningitis and hyperemia than the other groups. Therefore, it is possible to recommend the combination of albendazole and ivermectin as alternative chemotherapy for NCC due to its antiparasitic and anti-inflammatory effects, with potential to decrease the negative effects of the inflammatory burst when the parasite is killed within the CNS.

Characterization of excretory/secretory products of the Taenia crassiceps cysticercus involved in the induction of regulatory T cells in vivo.

The ability to modulate the host immune response has allowed some parasites to establish themselves in the tissues of an immunocompetent organism. While some parasite excretion/secretion products (ESPs) were recently reported to induce differentiation of regulatory T cells (Tregs), their identity is not known. This work is aimed to identify and characterize ESPs of Taenia crassiceps cysticerci linked with Treg induction in vivo. ESPs were obtained from cultures of T. crassiceps cysticerci and inoculated in mice, measuring Treg levels by flow cytometry. Proteins in ESPs were analyzed by electrophoresis; then, ESPs were classified as either differential or conserved. Differentially included proteins were MS-sequenced and functionally characterized. Only 4 of 10 ESPs induced Tregs. Proteins with catalytic activity and those involved in immunological processes predominated, supporting the idea that these molecules could play an important role in the induction of Tregs.

The effects of thioredoxin peroxidase from Cysticercus cellulosae excretory-secretory antigens on TGF-ß signaling pathway and Th17 cells differentiation in Jurkat cells by transcriptomics.

Thioredoxin peroxidase (TPx) protein from the excretory-secretory antigens (ESAs) of Cysticercus cellulosae (C. cellulosae) has been shown to regulate the differentiation of host Treg and Th17 cells, resulting in an immunosuppressive response dominated by Treg cells. However, the molecular mechanism by which TPx protein from the ESAs of C. cellulosae regulates the imbalance of host Treg/Th17 cell differentiation has not been reported. TPx protein from porcine C. cellulosae ESAs was used to stimulate Jurkat cells activated with PMA and ionomycin at 0, 24, 48, and 72 h. Transcriptomic analysis was performed to investigate the signaling pathways associated with Jurkat cells differentiation regulated by TPx protein from C. cellulosae ESAs. Gene Set Enrichment Analysis (GSEA) revealed that TPx protein from porcine C. cellulosae ESAs could induce upregulation of the TGF-ß signaling pathway and downregulation of Th17 cell differentiation in Jurkat cells. TPx protein from porcine C. cellulosae ESAs can activate the TGF-ß signaling pathway in Jurkat cells, thereby regulating the differentiation of Treg/Th17 cells and leading to an immunosuppressive response dominated by Treg cells, enabling evasion of the host immune attack. This study provides a foundation for further validation of these pathways and further elucidates the molecular mechanisms underlying immune evasion caused by porcine C. cellulosae.

In vitro system for the growth and asexual multiplication of Taenia crassiceps cysticerci.

Taenia solium is the aetiological agent of cysticercosis, a zoonosis that causes severe health and economic losses across Latin America, Africa and Asia. The most serious manifestation of the disease is neurocysticercosis, which occurs when the larval stage (cysticercus) establishes in the central nervous system. Using Taenia crassiceps as an experimental model organism for the study of cysticercosis, we aimed to identify the in vitro conditions necessary to allow parasite development at the short- and long terms. First, cysticerci were incubated for 15 days in different media and parasite densities. The number of buddings and cysticerci diameter were measured to evaluate asexual multiplication and parasite growth, respectively. Vitality was determined by trypan blue staining and morphology analysis. As a result, high cysticerci density and medium containing FBS and the excretion/secretion (E/S) products of feeder cells induced parasite survival, growth and multiplication. Then, the long-term (5 weeks) incubation of the parasites in co-culture with feeder cells was evaluated. Consequently, the mammalian cell lines induced a significant increase in total parasite volume while axenic cultures did not show any statistically significant change over time. In this study, the proper conditions to maintain T. crassiceps in vitro are described for the first time in a simpler and more controlled setting other than experimental infections. In addition, it was shown that cysticerci growth, survival and asexual multiplication depend on a complex network of secreted factors from both parasite and host.

In vitro metabolic stress induced by nitazoxanide and flubendazole combination in Taenia crassiceps cysticerci.

Taenia crassiceps is often used as experimental model for T. solium cysticercosis studies. Currently cysticercosis antiparasitic treatment is based on albendazole and praziquantel which may present side effects and parasitic resistance. The search for other antiparasitic drugs is necessary. Nitazoxanide (NTZ) and flubendazole (FLB) are broad spectrum antiparasitic drugs that present anti-cysticercosis effect. Metabolic analyses help to determine the impact of these drugs on parasites. The aim of this study was to determine the impact on the production and excretion of organic metabolites in T. crassiceps cysticerci after in vitro exposure to NTZ and FLB, isolated or in combination. T. crassiceps cysticerci were culture in RPMI medium and exposed to 10 µg/mL of NTZ, 10 µg/mL of FLB or 10 µg/mL of NTZ +10 µg/mL of FLB. 24 h after exposure, the parasites were chromatographic analyzed to determine the impact of these drugs on glycolysis, homolactic fermentation, tricarboxylic acid cycle, fatty acids oxidation and proteins catabolism. It was possible to determine that the drugs combination induced greater metabolic impact on cysticerci in comparison to the isolated drugs exposure. The drugs combination induced gluconeogenesis, metabolic acidosis, increase in tricarboxylic acid cycle and in proteins catabolism. While the NTZ isolated exposure induced metabolic acidosis and protein catabolism and the FLB isolate exposure induced gluconeogenesis and protein catabolism. These results show that the combination of drugs with different modes of action increase the antiparasitic effect and may be indicated as alternative cysticercosis treatments.

Identification and expression analysis of a new small ubiquitin-like modifier from Taenia pisiformis.

The small ubiquitin-like modifier (SUMO) plays important roles, with the SUMOylation pathway as one of its core components. In the present work, a single SUMO gene was initially identified from Taenia pisiformis and designated as TpSUMO. Bioinformatic analysis showed that the TpSUMO gene contained a 309 bp open reading frame (ORF), encoding 102 amino acids, and had a predicted molecular weight of ∼12 kDa. The amino acid sequence of TpSUMO was deduced and it shared 44.00% identity with human SUMO2 (HsSUMO2) and exhibited more than 97.78% identity with SUMOs from Taenia and Echinococcus. TpSUMO possessed a putative non-consensus site (FK11MG) within its N-terminus and a typical di-glycine (GG) motif at the C-terminus. Basic local alignment search tool (BLAST) analysis showed that only a single SUMO-related ortholog was present in each set of known genome data for fourteen tapeworm species. The precursor His-TpSUMO-FL, mature His-TpSUMO-GG and mutant His-TpSUMO-GGK11R proteins (∼18 kDa) were expressed in Escherichia coli Rosseta (DE3), and rabbit polyclonal anti-TpSUMO was generated with a high titer of 1.28 × 105. In vitro SUMOylation assay results showed that TpSUMO multimer formation in the His-TpSUMO-GG reaction could be catalyzed by the human SAE1/SAE2 and UBC9 conjugation system, but K11R mutation disrupted TpSUMO chain synthesis. Quantitative real-time PCR (qRT-PCR) further revealed that TpSUMO was ubiquitously expressed in different stages of T. pisiformis and in higher levels during an early development phase (day 14) of adult worms. Immunofluorescence localization showed that TpSUMO was detected in the bladder wall of cysticerci, in the testis in immature segment, and within eggs in the gravid proglottids. These findings indicated that TpSUMO is a new member of the SUMO protein family and may play a vital role in regulation of functions within proteins involved in worm growth and development.

Evaluating the effect of curcumin on the metacestode of Taenia crassiceps.

Curcumin, a curcuminoid present in the rhizome of the plant Curcuma longa has multiple pharmacological effects including anticarcinogenic and anti-inflammatory properties. This work evaluates the anthelmintic effect of the curcumin molecule (98% pure) on Taenia crassiceps cysticerci viability in vitro. Cysticerci incubated in the presence of increasing concentrations of curcumin showed a dose-dependent mortality correlated with a significant increase in the production of reactive oxygen species and a partial inhibition of thioredoxin-glutathione reductase, the only disulfide reductase present in these parasites. At 500 µM curcumin, a 100% of cysticerci lethality was obtained after 2 h of treatment. These results suggest the curcumin-induced oxidative stress could be in the origin of the anthelminthic effect of curcumin. Mice with cysticerci were injected intraperitoneally with 20, 40, or 60 mM curcumin daily for 30 days. A decrease in the burden of cysticerci (46%) was observed with a 60 mM dose of curcumin, supporting this compound as a potential anthelmintic drug.

Decreased embryo implantation in rabbits infected with Taenia pisiformis.

Parasitic infections can have detrimental effects on the reproductive capacity of their hosts. Infections by the cestode Taenia pisiformis in rabbits is generally not associated with increased mortality of offspring or with loss of maternal body condition but can result in reduced fecundity, and increased circulating progesterone levels have been reported in infected does compared to uninfected ones. In the present study, the possibility that T. pisiformis infection affects fecundity by reducing embryonic implantation was examined. Seven anesthetized New Zealand does were orally infected with 1000 eggs of T. pisiformis, and seven were administered saline. Seven weeks after infection, does were mated, and 7 days after, humanely sacrificed. A decrease in the number of implanted embryos and a decrease in the size of the embryo vesicles in infected does were observed (P ≤ 0.02, Student's t-test). There was a negative correlation between the number of hepatic granulomas and embryo implantation (ρ = - 0.8, P = 0.04, Spearman's test).

Comparison of mitochondrial genetic variation of Taenia hydatigena cysticerci from China and Mongolia.

Parasitic infection is one of the many challenges facing livestock production globally. Cysticercosis tenuicollis is a common parasitic disease in domestic and wild ruminants (intermediate host) caused by the larval stage of Taenia hydatigena that primarily infects dogs (definitive host). Although genetic studies on this parasite exist, only a few describe the genetic variation of this parasite in Mongolia. Our aim was thus, to identify the mitochondrial differences in ovine isolates of Cysticercus tenuicollis entering China from Mongolia and comparison with existing Chinese isolates from sheep and goats based on the recently described PCR-RFLP method and mitochondrial genes of NADH dehydrogenase subunit 4 (nad4) and the NADH dehydrogenase subunit 5 (nad5). Sixty-nine isolates were collected during routine veterinary meat inspections from sheep that originated from Mongolia, at the modern slaughterhouses in Erenhot City, Inner Mongolia. Additional 114 cysticerci were also retrieved from sheep and goats from northern (Inner Mongolia Autonomous Region, Ningxia Hui Autonomous Region, and Gansu Province), western (Tibet Autonomous Region), and southern (Jiangxi Province and Guangxi Province) China. The PCR-RFLP approach of the nad5 showed nine mitochondrial subclusters A1, A2, A3, A5, A8, A9, A10, A11, and B of T. hydatigena isolates from sheep and goats from Mongolia and China. Meanwhile, haplogroup A1 RFLP profile was more widespread than other variants. These data supplements existing information on the molecular epidemiology of T. hydatigena in China and Mongolia and demonstrate the occurrence of similar genetic population structures in both countries.

Molecular characterization of Cysticercus tenuicollis isolates from sheep in the Nile Delta, Egypt and a review on Taenia hydatigena infections worldwide.

The predator­prey-transmitted cestode Taenia hydatigena infects a wide range of definitive and intermediate hosts all over the world. Domestic and sylvatic cycles of transmission are considered as well. The parasite has considerable economic importance, particularly in sheep. Here, the molecular characters of T. hydatigena cysticerci in sheep from the Nile Delta, Egypt were investigated for the first time. For this purpose, 200 sheep carcasses and their offal were inspected at the municipal abattoir, Dakahlia governorate, Egypt. Cysticerci of T. hydatigena were collected and molecularly characterized employing the mitochondrial 12S rRNA gene. Cysticerci were found in 42 (21%) sheep, mostly attached to the omenti, mesenteries and livers. After molecular confirmation, nine isolates were sequenced displaying six different haplotypes. Analysis of the T. hydatigena 12S rRNA nucleotide sequences deposited in GenBank revealed 55 haplotypes out of 69 isolates, displaying high haplotype (0.797) and low nucleotide (0.00739) diversities. For the Tajima D neutrality index, a negative value (−2.702) was determined, indicating the population expansion of the parasite. Additionally, global data summarized in this study should be useful to set up effective control strategies against this ubiquitous parasite.

Generation and application of a monoclonal antibody against the 18-kDa oncosphere antigen of Taenia pisiformis.

Taenia pisiformis is a parasite that causes cysticercosis pisiformis, which has acquired economic relevance because of its effects on animal welfare and production. A useful assay for the detection of T. pisiformis is needed for the prevention of cysticercosis pisiformis and control of the parasite. The 18-kDa oncosphere antigen is expressed in the oncosphere of several cysticerci in species of the genus Taenia, including T. pisiformis. This protein plays an important role in tissue invasion and has extensive applications in diagnosis. In this study, the T. pisiformis 18-kDa oncosphere antigen (TPO18) was expressed in soluble form and successfully purified for use in the production of monoclonal antibodies (MAbs) against TPO18. Twenty hybridomas were obtained using ELISA, and the subcloning process identified three positive hybridoma cell lines, which were designated as 4E8, 5G5, and 7E8. MAb 7E8 exhibited the highest titer and had an IgG2b heavy chain and a kappa light chain. Western blot analysis demonstrated that MAb 7E8 reacted with GST-TPO18. Immunohistochemistry showed that TPO18 was widely distributed in the drape and wall of uteri in adults of T. pisiformis adults and in the fibrous layer of the sucker and cyst cavity of T. pisiformis cysticerci. This research will provide a foundation for the development of diagnostic tools and will contribute to a better understanding of the functions of TPO18.

Cysticidal effect of a pure naphthoquinone on Taenia crassiceps cysticerci.

Cysticercosis is a disease caused by the metacestode of the parasite Taenia solium (T. solium). In humans, the most severe complication of the disease is neurocysticercosis. The drug of choice to treat this disease is albendazole; however, the bioavailability and efficacy of the drug are variable. Therefore, new molecules with therapeutic effects against this and other parasitic infections caused by helminths must be developed. Naphthoquinones are naphthalene-derived compounds that possess antibacterial, antifungal, antitumoral, and antiparasitic properties. The aim of this work was to evaluate the in vitro anti-helminthic effect of 2-[(3-chlorophenylamino)phenylmethyl]-3-hydroxy-1,4-naphthoquinone, isolated from a natural source and then synthesized (naphthoquinone 4a), using an experimental model of murine cysticercosis caused by Taenia crassiceps (T. crassiceps). This compound causes paralysis in the cysticerci membrane from day 3 of the in vitro treatment. Additionally, it induces changes in the shape, size, and appearance of the cysticerci and a decrease in the reproduction rate. In conclusion, naphthoquinone 4a has in vitro cysticidal activity on T. crassiceps cysticerci depending on the duration of the treatment and the concentration of the compound. Therefore, it is a promising drug candidate to be used in T. crassiceps and possibly T. solium infections.

Quantitative assessment of lesion load and efficacy of 3 cycles of albendazole in disseminated cysticercosis: a prospective evaluation.

BACKGROUND: The management of disseminated cysticercosis is unclear and largely considered hazardous. The role of albendazole remains controversial in such patients. METHODS: A tertiary care, University hospital-based prospective intervention study was conducted from December 2015 to December 2017. Patients with disseminated cysticercosis, defined as the presence of multiple viable neurocysticerci (≥ 3) in the brain along with involvement of an additional extra site, were included in the study. Patients with cysticercal encephalitis were excluded. A detailed evaluation, including ophthalmoscopy, ocular B scans, ultrasound abdomen, and X-rays were done. Albendazole was administered at a dose of 15 mg/kg/day in 3 cycles of 28 days each. All patients were also given adjuvant corticosteroids and anti-epileptic drugs. Clinical and radiological follow up was carried out at a difference of 3 months between each treatment cycle. For radiological quantification, lesions were counted at 10 pre-specified levels. Statistical analysis was done to estimate the difference in seizure frequency and lesion load. RESULTS: Twenty-nine patients (21 with > 20 lesions; 8 with ≤ 20 lesions) were given albendazole as per the protocol. There was a significant reduction in the occurrence of seizures (P < 0.001) and headache (P < 0.001). A significant reduction in lesion load from baseline to third follow-up was seen in the estimations done at different levels (P < 0.001). No patient developed serious side-effect warranting cessation of therapy. CONCLUSION: Cyclical use of albendazole appears efficacious in treating disseminated cysticercosis. The method of quantification described may be used in future studies for objective assessment. TRIAL REGISTRATION: ISRCTN11630542; 28th September 2019; Retrospectively registered.

Mimotope-based antigens as potential vaccine candidates in experimental murine cysticercosis.

Human cysticercosis is a public health problem caused by Taenia solium metacestodes; thus, eradication of T. solium transmission by vaccination is an urgent requirement. The Cc48 mimotope from T. solium cysticerci was tested expressed in phage particles (mCc48) and chemically synthesized (sCc48) as a vaccine candidate in experimental murine cysticercosis. For this, BALB/c mice were immunized with mCc48 (G1; n = 40), sCc48 (G2; n = 40) and phosphate-buffered saline (PBS) (G3; n = 40, positive control) and challenged with Taenia crassiceps metacestodes. Another PBS group without parasite challenge was used as a negative control (G4; n = 40). Mice were sacrificed 15, 30, 45 and 60 days post-infection for cysticerci and serum collection. Immunization efficacy was determined by cysticerci counting. Serum samples were tested by ELISA to verify antibody (IgM, IgG, IgA and IgE) and cytokine (IFNγ and IL-4) levels. The sCc48 achieved the highest rates of protection and efficacy (90 and 98%, respectively). The group immunized with mCc48 presented the highest reactivity for IgM, IgG and IgE. All groups presented IL-4, but IFNγ was quite variable among groups. The protection induced by sCc48 synthetic peptide supports further studies of this mimotope as a potential vaccine candidate against cysticercosis.

In vitro nitazoxanide exposure affects energetic metabolism of Taenia crassiceps.

Nitazoxanide (NTZ) is a broad-spectrum drug used in intestinal infections, but still poorly explored in the treatment of parasitic tissular infections. This study aimed to evaluate the in vitro responses of the energetic metabolism of T. crassiceps cysticerci induced by NTZ. The organic acids of the tricarboxylic acid cycle, products derived from fatty acids oxidation and protein catabolism were analyzed. These acids were quantified after 24 h of in vitro exposure to different NTZ concentrations. A positive control group was performed with albendazole sulfoxide (ABZSO). The significant alterations in citrate, fumarate and malate concentrations showed the NTZ influence in the tricarboxylic acid (TCA) cycle. The non-detection of acetate confirmed that the main mode of action of NTZ is effective against T. crassiceps cysticerci. The statistical differences in fumarate, urea and beta-hydroxybutyrate concentrations showed the NTZ effect on protein catabolism and fatty acid oxidation. Therefore, the main energetic pathways such as the TCA cycle, protein catabolism and fatty acids oxidation were altered after in vitro NTZ exposure. In conclusion, NTZ induced a significant metabolic stress in the parasite indicating that it may be used as an alternative therapeutic choice for cysticercosis treatment. The use of metabolic approaches to establish comparisons between anti parasitic drugs mode of actions is proposed.