In vitro efficacy of herbicides on Sarcocystis cruzi bradyzoites

Sarcocystis causes various veterinary and human infections. A few agents are available for treating Sarcocystis infections, but their mechanisms of action are not known. Phytohormonal herbicides are antiparasitic agents that reduce the viability of organisms belonging to the phylum, Apicomplexa. Some of these herbicides prevent Apicomplexan parasites from infecting cells and organisms, yet the effects of such drugs on Sarcocystis are unclear. We evaluated the activity of phytohormonal herbicides against Sarcocystis bradyzoites using mortality and morphological changes with methylene blue staining as an indicator. Antiparasitic activity of 17 agrochemicals that act on plant plastids—classified into the following six herbicide groups: acetyl-CoA carboxylase (ACC) inhibitors, acetolactate synthase (ALS) inhibitors, photosynthesis inhibitors, protoporphyrinogen oxidase (protox) inhibitors, carotenoid biosynthesis pathway inhibitors, very-long-chain fatty acid (VLCFA) biosynthesis inhibitors, and auxinlike herbicides—were examined. The in vitro system enables the screening of drugs against Sarcocystis species, for which a well-established culturing method is not yet available. Nine herbicides, including ALS inhibitors, ACC inhibitors, and auxin-like herbicides, caused mortality of Sarcocystis cruzi bradyzoites by more than 90%. Further, all ACC inhibitors caused the formation of vacuolar structures in bradyzoites, and two ALS inhibitors caused bradyzoites rounding

Discovery of genome of an immunodeficiency-associated virus-like virus from pig feces in Japan

Immunodeficiency-associated stool virus (IASV) is an unclassified virus, for which the only genome information is available from a patient infected by human immunodeficiency virus. In domestic animals, one report described detection of IASV-like virus in pig feces, whereas no nucleotide sequence information of this virus is currently available. Using deep sequencing method, we detected a DNA fragment homologous to IASV in several pig feces in Japan. The sequence of the PCR product in this sample had 70% homology to that of IASV. The infectious rate of the IASV-like virus was 72.9% among the 9 pig farms, from which the samples were collected. There was no clear correlation between the presence of IASV-like virus and the fecal characteristics

Prevalence of Agamid adenoviruses of the bearded dragons (Pogona vitticeps) in Japan

In this study, we surveyed the prevalence and characteristics of agamid adenovirus (genus Atadenovirus) infections in bearded dragons (Pogona vitticeps) in Japan. Swab samples were collected from the oral cavity and pharynx of 44 healthy bearded dragons and 24 bearded dragons with clinical signs of respiratory disease. PCR confirmed agamid adenovirus in 25 of the 44 healthy lizards (56.8%). Of the 24 bearded dragons with respiratory clinical signs, 14 were agamid adenovirus-positive (58.3%). Sex was determined for 21 of the 24 bearded dragons with respiratory clinical signs (9 males and 12 females). Agamid adenovirus was confirmed in two of the nine males (22.2%) and 10 of the 12 females (83.3%), indicating a higher prevalence of adenovirus in the females. Overall, the prevalence of agamid adenovirus in bearded dragons with respiratory clinical signs was almost the same as that in clinically healthy bearded dragons, suggesting that the virus is widespread in this species. In addition, we detected no apparent seasonality in the occurrence of agamid adenovirus infection. The mean value of globulin was slightly higher in seven of the female lizards with confirmed agamid adenovirus

An Escherichia coli Expressed Multi-Disulfide Bonded SARS-CoV-2 RBD Shows Native-like Biophysical Properties and Elicits Neutralizing Antisera in a Mouse Model

A large-scale Escherichia coli (E. coli) production of the receptor-binding domain (RBD) of the SARS-CoV-2 could yield a versatile and low-cost antigen for a subunit vaccine. Appropriately folded antigens can potentially elicit the production of neutralizing antisera providing immune protection against the virus. However, E. coli expression using a standard protocol produces RBDs with aberrant disulfide bonds among the RBD’s eight cysteines resulting in the expression of insoluble and non-native RBDs. Here, we evaluate whether E. coli expressing RBD can be used as an antigen candidate for a subunit vaccine. The expressed RBD exhibited native-like structural and biophysical properties as demonstrated by analytical RP-HPLC, circular dichroism, fluorescence, and light scattering. In addition, our E. coli expressed RBD binds to hACE2, the host cell’s receptor, with a binding constant of 7.9 × 10−9 M, as indicated by biolayer interferometry analysis. Our E. coli-produced RBD elicited a high IgG titer in Jcl:ICR mice, and the RBD antisera inhibited viral growth, as demonstrated by a pseudovirus-based neutralization assay. Moreover, the increased antibody level was sustained for over 15 weeks after immunization, and a high percentage of effector and central memory T cells were generated. Overall, these results show that E. coli-expressed RBDs can elicit the production of neutralizing antisera and could potentially serve as an antigen for developing an anti-SARS-CoV-2 subunit vaccine