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Background: Leishmania is a vector-borne protozoon, which causes visceral, cutaneous and mucocutaneous leishmaniosis in human and animals. Monocyte-derived exosome vaccines can be used as prophylaxis and immunotherapy strategies. The aim of this study was to design a multiple-epitope candidate vaccine using leishmaniolysin (GP63) and rK39 proteins against Leishmania major and L. infantum for monocyte-derived exosome preparation. Methods: This study was carried out in Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran, 2023-2024. Effective immunodominant epitopes were selected from two antigenic proteins of GP63 and rK39 using various immunoinformatics and bioinformatics approaches. Vibrio cholerae ß-subunit was used as an adjuvant to stimulate immune responses. Then, appropriate linkers were selected for the fusion of epitopes. The 3D model of candidate vaccine was predicted and validated. Results: This designed candidate vaccine could effectively be used as a prophylaxis strategy against leishmaniosis. Conclusion: A candidate vaccine was designed using bioinformatic and immunoinformatic studies with virtual acceptable quality; however, effectiveness of this vaccine should be verified through further in-vitro and in-vivo studies.
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Objectives: In 2019, COVID-19 emerged in China and has since spread worldwide. Owing to the virus's ability to adhere to specific receptors, cats are susceptible to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The popularity of pet cats in Iran has sparked fears of human-cat-human transmission of the virus. This study aimed to identify positive cases in cats owned by people infected with SARS-CoV-2, to determine if they remained positive for >3 weeks and to examine the virus genome isolated from a number of cats and one of their owners. Methods: A total of 30 cats were sampled approximately 3 days after their owners tested positive (day 1), and 3 weeks later, in strict accordance with health regulations. Rectal and oropharyngeal samples were collected. All samples were subjected to a qualitative PCR and reverse transcription PCR. The S-gene region was partially sequenced in positive samples and the results were used to create a phylogenetic tree. Results: SARS-CoV-2 was detected in 7/30 (23.3%) cats examined. In the third week, every cat tested negative. The sequence data of positive cats and one of their owners revealed that the retrieved RNAs belonged to the alpha variation. The genetic distance between the samples and the reference sequence (20I/B.1.1.7: OM003849, MZ344997) was minimal, with a 99% similarity. Positive samples of cats had four mutations in gene S. Amino acid substitutions in the spike glycoprotein at positions N501Y, A570D, D614G and P681H were recorded in the isolates compared with 780 other sequences of Iranian strains. Conclusions and relevance: This study confirmed the presence of SARS-CoV-2-infected cats living in close contact with infected owners. Despite cats' susceptibility to COVID-19, the risk of severe infection in these animals is low, as evidenced by the lack of clinical signs in positive cats.
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OBJECTIVES: This study was aimed at detecting feline autosomal dominant polycystic kidney disease in a population of Persian and Persian-related breeds by a molecular method in Iran. METHODS: Buccal swab samples were collected from 47 cats and examined with a touchdown PCR method. Additionally, partial sequencing was performed in two cats with bilateral renal cysts. RESULTS: Twenty-two cats (46.8%) were diagnosed as heterozygous for this mutation. Sequence analysis of two cats showed C to A point mutation in the PKD1 gene, as in previous studies. CONCLUSIONS AND RELEVANCE: Prevalence of this disease is high in Iran, highlighting the need for molecular screening tests before including cats in breeding programmes.