Evaluating the Toxocara cati extract as a therapeutic agent for allergic airway inflammation.

BACKGROUND: The hygiene hypothesis suggests that early life exposure to helminth infections can reduce hypersensitivity in the immune system. OBJECTIVE: The present study aims to evaluate the effects of Toxocara cati (T. cati) somatic products on allergic airway inflammation. METHODS: Between 2018 and 2020, T. cati adult worms were collected from stray cats in Mashhad, Iran (31 out of 186 cats), and their somatic extract was collected. Thirty BALB/c mice were equally divided into three groups, including the OVA group (sensitized and challenged with ovalbumin), the somatic administered group (received somatic extract along with ovalbumin sensitization), and the PBS group (sensitized and challenged with phosphate buffer saline). Bronchoalveolar lavage (BAL) fluid was collected to assess the number of cells, and lung homogenates were prepared for cytokine analysis. Histopathological analysis of the lungs was performed, and inflammatory cells and mucus were detected. Cytokine levels (IL-4, IL-5, IL-10) were measured using enzyme-linked immunosorbent assay (ELISA), and ovalbumin-specific immunoglobulin E (IgE) levels were determined using a capture ELISA. RESULTS: The somatic group significantly decreased regarding the lung pathological changes, including peribronchiolitis, perivasculitis, and eosinophil influx, compared to the group treated with ovalbumin alone. These changes were accompanied by a decrease in proinflammatory cytokines IL-4 and IL-5 and an increase in the anti-inflammatory cytokine IL-10, indicating a shift toward a more balanced immune response. The number of inflammatory cells in the BAL fluid was also significantly reduced in the somatic group, indicating a decrease in inflammation. CONCLUSION: These preclinical findings suggest that in experimental models, T. cati somatic extract exhibits promising potential as a therapeutic agent for mitigating allergic airway inflammation. Its observed effects on immune response modulation and reduction of inflammatory cell infiltration warrant further investigation in clinical studies to assess its efficacy and safety in human patients.

First report of deutonymph Myianoetus, Willmann, 1937 (Acari: Astigmata) from Iran.

Myianoetus is a Histiostomatidae mites that are phoretic on flies. The relation between flies and phoretic mites is considered to be of potential value in forensic studies, as the development of flies associated with decomposing human remains. So, they may useful in determining the time of death of an individual. This study represents the first records of Myianoetus muscarum deutonymph phoretic on adult Musca domestica in Iran. Further studies are needed to find any relation between phoretic mites and flies.

Exacerbation of allergic asthma by somatic antigen of Echinococcus granulosus in allergic airway inflammation in BALB/c mice.

BACKGROUND: There is ample evidence demonstrating a reverse relationship between helminth infection and immune-mediated diseases. Accordingly, several studies have shown that Echinococcus granulosus infection and hydatid cyst compounds are able to suppress immune responses in allergic airway inflammation. Previous studies have documented the ability of hydatid cysts to suppress aberrant Th2 immune response in a mouse model of allergic asthma. However, there is a paucity of research on the effects of protoscoleces on allergic asthma. Thus, this study was designed to evaluate the effects of somatic antigens of protoscoleces in a murine model of allergic airway inflammation. METHODS: Ovalbumin (OVA)/aluminum hydroxide (alum) was injected intraperitoneally to sensitize BALB/c mice over a period of 0 to 7 days, followed by challenge with 1% OVA. The treatment group received somatic antigens of protoscoleces emulsified with PBS on these days in each sensitization before being challenged with 1% OVA on days 14, 15, and 16. The effects of somatic antigens of protoscoleces on allergic airway inflammation were evaluated by examining histopathological changes, the recruitment of inflammatory cells in the bronchoalveolar lavage, cytokine production in the homogenized lung tissue (IL-4, IL-5, IL-10, IL-17, and IFN-γ), and total antioxidant capacity in serum. RESULTS: Overall, administration of somatic antigens of protoscoleces exacerbated allergic airway inflammation via increased Th2 cytokine levels in the lung homogenate, recruitment of eosinophils into bronchoalveolar lavage fluid, and pathological changes. In addition, total antioxidant capacity and IFN-γ levels declined following the administration of somatic antigens. CONCLUSIONS: The results revealed that the co-administration of somatic products of protoscoleces with OVA/alum contributed to the exacerbation of allergic airway inflammation in BALB/c mice. Currently, the main cause of allergic-type inflammation exacerbation is unknown, and further research is needed to understand the mechanism of these interactions.

A survey on Toxocara cati eggs on the hair of stray cats: A potential risk factor for human toxocariasis in Northeastern Iran.

The objective of this study was to investigate the presence of Toxocara eggs on the hair of stray cats. The total number of stray cats trapped and included in the trial was 167 that were collected weekly from different residential areas of Mashhad, in northeastern Iran, from November 2016 to December 2017. Among the 167 cats, 18 (10.8%) of them were positive to T. cati eggs in their hair. In the positive cats, 7 (39%) were adult, 1 (6%) was juvenile and 10 (55%) were kittens. Overall, the mean number of eggs from positive cats was 3.9 ± 1.7 eggs per gram (epg) of hair per cat with an average of 3.1 ± 1.4 in adults, 4.9 in juveniles and 4.3 ± 1.6 in kittens. In total, 39.9% of the eggs recovered were non-viable 35.5% were viable, 22.2% were embryonating and 2.3% were embryonated which embryonated eggs were found only in juveniles. Based on our data, kittens were responsible for 61.7% of the total number of eggs. The age of the cat was found to be an important risk factor associated with parasitic infection.. This study showed that cat hair contaminated by T. cati eggs in different developmental stages represents of potential source for human toxocariasis.

Molecular Characterization of Echinococcus granulosus Sensu Lato from Livestock in North Khorasan Province, Iran.

BACKGROUND: Echinococcus granulosus is one the most important zoonotic disease which is endemic in worldwide. Molecular method has allowed discrimination of different genotypes (G1-G10), providing new approach in development of prevention and control program of hydatid cyst. This study was conducted to identify the genotypes of E. granulosus from domestic animals in nine districts of North Khorasan Province using the mitochondrial cox1 gene sequence. METHODS: Overall, 122 hydatid cyst were collected during 2016-2017 from sheep (n=43) and cattle (n=79). DNA was extracted from protoscoleces and germinal layers and amplified by PCR. Phylogenetic analysis was also performed by analyzing the complete nucleotide sequences of mitochondrial cytochrome C oxidase subunit 1 (cox1) of E. granulosus genotypes from various locations. RESULTS: Sequencing of the amplified products revealed the presence of G1 as dominant genotype, G3 and Echinococcus canadenesis in one isolate each. Altogether, 9 haplotypes were detected based on cox1 gene. Haplotype 3 was the common variant that found in 58 including 42 cattle and 16 sheep. CONCLUSION: This study provided knowledge on the identity of E. granulosus cysts collected from sheep and cattle in North Khorasan Province. Furthermore, these results showed the potentials of sheep as a main source of infection to humans, contributing the transmission and maintain of hydatid cyst in this region.

Somatic extracts of Marshallagia marshalli downregulate the Th2 associated immune responses in ovalbumin-induced airway inflammation in BALB/c mice.

BACKGROUND: Recently the role of gastrointestinal nematodes in modulating the immune responses in inflammatory and immune-mediated conditions such as allergy and autoimmune diseases has been introduced. This is mainly due to the suppressive effects of somatic and excretory secretory (ES) products of nematodes on the immune responses. In this study, we evaluated the immunomodulatory potentials of somatic products of Marshallagia marshalli, a gastrointestinal nematodes of sheep, to suppress the immune-mediated responses in a murine model of allergic airway inflammation. BALB/c mice were intraperitoneally (IP) sensitized with ovalbumin (OVA)/Alum and then challenged with 1% OVA. Somatic products of M. marshalli were administered during each sensitization. The effects of somatic products on development of allergic airway inflammation were evaluated by analyzing inflammatory cells recruitment, histopathological changes, cytokines production (IL-4, IL-13, IL-10, TGF-ß) and serum antibody titers (IgG1, IgG2a). RESULTS: Somatic products of M. marshalli were able to suppress the induction of allergic airway inflammation in mice. Modulation of Th2 type responses (IL-4, IL-13, IgG1) via upregulations of IL-10 and TGF-ß production was observed after injection of somatic products of M. marshalli. In addition, inflammatory cells infiltration and pathological disorders were significantly diminished following administration of somatic products. CONCLUSIONS: Our data raised the possibility that helminths could be a potential therapeutic candidate to alleviate the inflammatory conditions in allergic asthma. According to these results, we concluded that M. marshalli may contain immune-modulatory molecules that attenuate allergic airway inflammation via induction of regulatory cytokines. Further investigations are required to identify molecules that might have potentials for development of novel therapeutic targets.