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Toxoplasma gondii is an apicomplexan parasite infecting all mammals including humans and causes toxoplasmosis. There is no vaccine available for humans and thus vaccine development efforts continue using novel antigens and/or vaccine platforms. Since our previous microarray screening study showed that ROP6 is a suitable antigen to be used in vaccine studies, in this study, we aimed to design an optimized mRNA construct encoding the ROP6 protein and then demonstrate its efficiency and immunogenicity using in vitro methods. For this, we constructed a pT7CFE1-Chis/ROP6 vector encoding optimized ROP6 mRNA containing EMCV 5'UTR with IRES and a 20 nucleotides fragment from alpha globin 3' UTR. Then, we generated the optimized ROP6 mRNAs with anti-reverse cap analogue (ARCA) and approximately 150 nucleotide long poly-A tail. Next, HEK293T cells were transfected with the optimized ROP6 mRNAs to show recombinant ROP6 protein expression capability. Moreover, we expressed in vitro recombinant ROP6 protein in HeLa cell lysate using the pT7CFE1-Chis/ROP6 vector to reveal the immunogenicity of recombinant ROP6 protein using sera samples collected from mice infected with PRU strain of T. gondii. The IFA and Western blot results showed that the optimized ROP6 mRNAs successfully expressed the recombinant ROP6 protein in HEK293T cells. Moreover the recombinant ROP6 protein expressed in HeLa cell lysate strongly reacted with sera samples collected from mice. The absorbance difference detected among positive and negative mice serum samples analyzed was statistically significant, indicating that the recombinant ROP6 protein was immunogenic (P = 0.0003). In conclusion, this study demonstrated that the optimized ROP6 mRNAs can be used in the development of mRNA vaccines against toxoplasmosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Toxoplasma gondii is an obligate intracellular parasite that can infect a variety of mammals including humans and causes toxoplasmosis. Unfortunately, a protective and safe vaccine against toxoplasmosis hasn't been developed yet. In this study, we developed a DNA vaccine encoding the SRS13 protein and immunized BALB/c mice thrice with pVAX1-SRS13 through the intramuscular route (IM) or intradermally using an electroporation device (ID + EP). The immunogenicity of pVAX1-SRS13 was analyzed by ELISA, Western blot, cytokine ELISA, and flow cytometry. The protective efficacy of the pVAX1-SRS13 was investigated by challenging mice orally with T. gondii PRU strain tissue cysts. The results revealed that pVAX1-SRS13 administered through IM or ID + EP routes induced high level of anti-SRS13 IgG antibody responses (P = 0.0037 and P < 0.0001). The IFN-γ level elicited by the pVAX1-SRS13 (ID + EP) was significantly higher compared to the control group (P = 0.00159). In mice administered with pVAX1-SRS13 (ID + EP), CD8 + cells secreting IFN-γ was significantly higher compared to pVAX1-SRS13 (IM) (P = 0.0035) and the control group (P = 0.0068). Mice vaccinated with the SRS13 DNA vaccine did not induce significant IL-4 level. Moreover, a significant reduction in the number of tissue cysts and the load of T. gondii DNA was detected in brains of mice administered with pVAX1-SRS13 through ID + EP and IM routes compared to controls. In conclusion, the SRS13 DNA vaccine was found to be highly immunogenic and confers strong protection against chronic toxoplasmosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Enterocytozoon bieneusi is the most common species found in humans. Although E. bieneusi has been investigated in humans, genotype profile of E. bieneusi is not known in Türkiye., Methods: In this study, we screened E. bieneusi in patients (n = 94) with different types of malignant solid tumors by Real Time PCR and then sequenced E. bieneusi positive samples. All cancer patients were undergoing chemotherapy and had diarrhea. Moreover, as control groups, we also screened E. bieneusi in patients with diarrhea (n = 50) and without diarrhea (n = 50)., Results: Among all patients analyzed, 33 (17%) were found to be E. bieneusi-positive. As the patients were categorized, the molecular prevalence of E. bieneusi increased to 25.5% among cancer patients with diarrhea. However, the molecular prevalence of E. bieneusi was found to be lower in patients with presenting only diarrhea (8%) and patients without diarrhea (10%). The high molecular prevalence value detected among cancer patients with diarrhea was also statistically significant compared to other patient groups (P = 0.00112 and P = 0.0269). Among the 33 Real Time PCR positive samples, 10 of them were amplified by nested PCR and among these 10 samples, 6 of them were successfully genotyped. The phylogenetic tree showed the presence of D and Type IV which were also identified in stray cats living in İzmir in our previous study., Conclusions: High molecular prevalence value indicates the importance of screening stool samples of cancer patients with diarrhea for E. bieneusi and genotyping results indicate that D and Type IV are circulating between humans and cats., (© 2024. The Author(s).)

Severe acute respiratory syndrome coronavirus 2 had devastating consequences for human health. Despite the introduction of several vaccines, COVID-19 continues to pose a serious health risk due to emerging variants of concern. DNA vaccines gained importance during the pandemic due to their advantages such as induction of both arms of immune response, rapid development, stability, and safety profiles. Here, we report the immunogenicity and protective efficacy of a DNA vaccine encoding spike protein with D614G mutation (named pcoSpikeD614G) and define a large-scale production process. According to the in vitro studies, pcoSpikeD614G expressed abundant spike protein in HEK293T cells. After the administration of pcoSpikeD614G to BALB/c mice through intramuscular (IM) route and intradermal route using an electroporation device (ID + EP), it induced high level of anti-S1 IgG and neutralizing antibodies (P < 0.0001), strong Th1-biased immune response as shown by IgG2a polarization (P < 0.01), increase in IFN-γ levels (P < 0.01), and increment in the ratio of IFN-γ secreting CD4 + (3.78-10.19%) and CD8 + (5.24-12.51%) T cells. Challenging K18-hACE2 transgenic mice showed that pcoSpikeD614G administered through IM and ID + EP routes conferred 90-100% protection and there was no sign of pneumonia. Subsequently, pcoSpikeD614G was evaluated as a promising DNA vaccine candidate and scale-up studies were performed. Accordingly, a large-scale production process was described, including a 36 h fermentation process of E. coli DH5α cells containing pcoSpikeD614G resulting in a wet cell weight of 242 g/L and a three-step chromatography for purification of the pcoSpikeD614G DNA vaccine., (© 2024. The Author(s).)

Prion diseases are fatal neurodegenerative diseases affecting humans and animals. A relationship between variations in the prion gene of some species and susceptibility to prion diseases has been detected. However, variations in the prion protein of cats that have close contact with humans and their effect on prion protein are not well-known. Therefore, this study aimed to investigate the variations of prion protein-encoding gene (PRNP gene) in stray cats and to evaluate variants detected in terms of genetic factors associated with susceptibility or resistance to feline spongiform encephalopathy using bioinformatics tools. For this, cat DNA samples were amplified by a PCR targeting PRNP gene and then sequenced to reveal the variations. Finally, the effects of variants on prion protein were predicted by bioinformatics tools. According to the obtained results, a novel 108 bp deletion and nine SNPs were detected. Among SNPs, five (c314A>G, c.454T>A, c.579G>C, c.642G>C and c.672G>C) were detected for the first time in this study. Bioinformatics findings showed that c.579G>C (Q193H), c.454T>A (Y152N) and c.457G>A (E153K) variants have deleterious effects on prion protein and c.579G>C (Q193H) has high amyloid propensities. This study demonstrates prion protein variants of stray cats and their deleterious effects on prion protein for the first time., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Tick-borne pathogens increasingly threaten animal and human health as well as cause great economic loss in the livestock industry. Among these pathogens, Anaplasma ovis causing a decrease in meat and milk yield is frequently detected in sheep in many countries including Turkey. This study aimed to reveal potential vaccine candidate epitopes in Msp4 protein using sequence data from Anaplasma ovis isolates and then to design a multi-epitope protein to be used in vaccine formulations against Anaplasma ovis. For this purpose, Msp4 gene was sequenced from Anaplasma ovis isolates (n:6) detected in ticks collected from sheep in Turkey and the sequence data was compared with previous sequences from different countries in order to detect the variations of Msp4 gene/protein. Potential vaccine candidate and diagnostic epitopes were predicted using various immunoinformatics tools. Among the discovered vaccine candidate epitopes, antigenic and conserved were selected, and then a multi-epitope protein was designed. The designed vaccine protein was tested for the assessment of TLR-2, IgG, and IFN-g responses by molecular docking and immune simulation analyses. Among the discovered epitopes, EVASEGSGVM and YQFTPEISLV epitopes with properties of high antigenicity, non-allergenicity, and non-toxicity were proposed to be used for Anaplasma ovis in further serodiagnostic and vaccine studies., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.)

The Fertile Crescent appears to be the most plausible region where the domestication of cats commenced through a mutually beneficial relationship between wild cats and early agrarian societies. These domesticated cats then journeyed across the globe mirroring the paths of human migration. An examination of mitochondrial DNA (mtDNA) control region-based mitotyping suggested that a significant majority, exceeding 80%, of globally sampled random-bred and pure-bred cats could be categorized into 12 predominant mitotypes. However, the extent of mitotype diversity within random-bred cats from regions proximate to the Fertile Crescent remains inadequately explored. In light of this we aimed to investigate the mitotype diversity in random bred cats sampled from various regions across Turkey. Additionally, we sought to establish a comparison with the mitotype profiles of locally recognized pure breeds, namely the Turkish Angora and Turkish Van. To unravel their evolutionary narratives, we engaged in comprehensive population genetics analyses at both the individual and mitotype-based levels. Our study encompassed a sample size of 240 specimens, forming the basis for both mitotyping and population genetics scrutiny. Our analysis yielded the identification of nine 'universal' mitotypes (A-J), alongside an 'outlier' mitotype group I. Notably mitotypes A and D emerged as particularly prevalent in contrast to the lesser occurrence mitotypes C, G, and H. With the realm of random bred cats the structure of haplotypes exhibited remarkable diversity presenting distinctions from Turkish Angora and Van breeds. Nucleotide diversity was higher compared to previous reports from Turkey and was one of the highest among reported world cat population estimates. Intriguingly, our investigations did not unveil any pronounced instances of strong selection, population expansions or contractions within any specific population or mitotype. To conclude, our study represents a pioneering effort in uncovering the mitotype profiles and haplotype structures inherent to both random-bred and pure breed cats in Turkey. This endeavor not only broadens our understanding of the feline genetic landscape within the region but also lays the foundation for future inquiries into the evolutionary trajectories and genetic legacies of these feline populations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Cytokine storm is an important cause of death in COVID-19 patients. A recent clinical study showed that administration of recombinant interferon lambda 1 (IFN-λ1 or IL-29) may prevent severe COVID-19. On the other hand, IL-6 has been associated as a prognostic marker of worsening for COVID-19 patients. The objective of this study is to screen IFN-λ1, IL-6 and antibody levels in consecutive serum sample sets of COVID-19 patients. A total of 365 serum samples collected from 208 hospitalized COVID-19 patients were analyzed for IFN-λ1 and IL-6 levels as well as SARS-CoV-2 neutralizing antibodies and anti-S1 IgG antibodies. Analyses of serum samples for cytokine levels showed that IFN-λ1 (>8 pg/mL) and IL-6 (>2 pg/mL) were detected in approximately 64% and 21% patients, respectively. A decrement in IFN-λ1 levels and IL-6 levels above 35 pg/mL can be sign of clinical severity and upcoming dead. An increment in IL-6 levels wasn't detected in every COVID-19 patient but a decrement in IL-6 levels was related to clinical improvement. Importantly, the detection of IFN-λ1 level together with an increase in anti-S1 IgG antibody response were observed in clinically improved patients. Screening severe COVID-19 patients for IFN-λ1, IL-6, and anti-S1 IgG antibody levels during their hospital stay especially in intensive care units may be beneficial to monitor the clinical status and management of treatment strategies. Importantly, detection of IFN-λ1 together with protective IgG antibody response can be an indication of clinical improvement in severe COVID-19 patients and these patients may be discharged from the hospital soon., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Susceptibility to classical bovine spongiform encephalopathy (BSE) has been linked to 23 bp indel in promoter and 12 bp indel in the first intron of cattle prion protein gene. This study aimed to investigate 23/12 bp indel polymorphisms in the polymorphisms in cattle prion protein ( PRNP ) gene to reveal the risk of BSE in Ethiopian cattle. Also, frequency of each polymorphism was compared to the other Bos taurus and Bos indicus breeds. According to results, the insertion variant was detected at a low frequency in all of the study populations at both loci. The 23 bp insertion allele in Fogera breed was relatively lower than Borona and Arsi and the same allele at the same locus in Afar breed was higher than the rest of the breeds (0.16). Due to high linkage disequilibrium (LD) of the deletion allele in Bos taurus , the frequencies of deletion allele at 23 bp (0.84) and 12 bp (0.86) loci in Afar breed were relatively closer than the rest of the breeds. In addition, DD/DD was found as the highly frequent diplotype in all of the breeds. The low frequency of insertion alleles at 23 and 12 bp indel sites demonstrate that Ethiopian cattle have a genetically high risk for BSE.

The phylum Microsporidia includes obligate intracellular parasites that can infect humans and various animals. To date, 17 different species within the phylum have been reported to infect humans. Among them, Enterocytozoon bieneusi (E. bieneusi) is one of the most frequently detected species in humans. Identification of E. bieneusi as well as its genotypes in humans and animals is important to reveal their role in transmission to each other. Cats are blamed as the source of E. bieneusi transmission to humans. In this study, we aimed to genotype 170 E. bieneusi positive samples isolated from stool of stray cats living in İzmir province of Türkiye. According to the results, 47 samples were amplified by nested PCR protocol targeting ITS region and successfully sequenced. The phylogenetic analysis showed the presence of zoonotic genotype D and type IV in stray cats, which are also frequently detected in humans. Among the E. bieneusi genotypes detected, the prevalence of type IV (93.6%; 44/47) was very high compared to genotype D. Overall, the identification of zoonotic genotypes of E. bieneusi supports that stray cats can play an important role in the transmission of E. bieneusi to humans in İzmir., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Toxoplasma gondii is one of the main pathogens causing abortion in sheep. In this study, an in house ELISA using recombinant GRA1 and BAG1 proteins as antigen was used to detect T. gondii infection in a flock of sheep suffering from abortions. Serum samples collected from sheep (n = 23) the day after abortion were initially analyzed with a commercial ELISA using recombinant P30 (SAG1) protein as antigen and then by the in house ELISA using recombinant GRA1 and BAG1 proteins as antigen. Commercial ELISA detected anti-T. gondii IgG antibodies in 20 samples whereas in house ELISA detected anti-T. gondii IgG antibodies in 19 samples. The results of the remaining three serum samples that were seronegative by commercial ELISA were also seronegative by in house ELISA. According to the results of commercial ELISA and in house ELISA, the seroprevalence of ovine toxoplasmosis was 86.9% and 82.6%, respectively. When we accept the validated commercial ELISA as a reference method, the sensitivity and specificity of in house ELISA can be considered as 95% and 100%. These preliminary results show that in house ELISA using recombinant GRA1 and BAG1 proteins as antigen can detect ovine toxoplasmosis successfully., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023. Published by Elsevier Ltd.)

Background: Bartonella henselae is one of the most commonly identified Bartonella species associated with several human diseases. Although B. henselae was detected in humans and cats in Turkey, they have not been genotyped previously. Therefore, this study aimed to genotype B. henselae samples (n = 44) isolated from stray cats using the multi-locus sequence typing (MLST) method. For this aim, eight different housekeeping markers were amplified by nested PCR and then sequenced to reveal sequence types (STs) of B. henselae samples., Results: Allelic profiles obtained from 40 B. henselae isolates (90.9%) were compatible with available allelic profiles in the MLST online database. However, allelic profiles obtained from the remaining 4 B. henselae isolates (9.1%) were incompatible with the database. Among B. henselae isolates with compatible allelic profiles, 5 different STs including ST1, ST5, ST9, ST35 and ST36 were identified according to the B. henselae MLST online database. ST35 was the most prevalent ST with a prevalence rate of 29.5% (13/44), followed by ST36 with a prevalence rate of 22.7% (10/44). In addition, ST5 (16%, 7/44) and ST9 (18.2%, 8/44) were also among the prevalent STs. The prevalence of ST1 was 4.5% (2/44). For B. henselae isolates with incompatible allelic profiles, we recommended a new ST called ST38., Conclusion: The present study genotyped B. henselae samples isolated from stray cats in Turkey for the first time and ST1, ST5, ST9, ST35, and ST36 as well as a new sequence type named ST38 were identified among these B. henselae isolates., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Toxoplasma gondii is a protozoan parasite that may infect many mammals including humans. Cats are one of the main sources of infection for humans. Therefore, routine screening of cats with tests that are inexpensive, rapid, and do not require sophisticated laboratory equipment is important. In this study, a lateral flow assay (LFA) was designed to rapidly diagnose toxoplasmosis in cats. For this purpose, we selected GRA1 protein of T. gondii due to its high antigenicity in diagnostic and vaccine studies. We further analyzed the immunological properties of GRA1 protein using in silico tools. Then, we expressed and purified recombinant GRA1 (rGRA1) protein and used it during the development of LFA to detect toxoplasmosis in serum samples (n = 40) of cats. According to the results, rGRA1 protein has negative GRAVY value, high aliphatic index, alpha helix, random coil and 12 B cell epitopes. The in silico data supported the high antigenic properties of rGRA1 protein and showed that it can be a good antigen candidate for LFA. Among 30 cat positive serum samples, 27 were found positive by the LFA while seronegative sera (n = 10) were negative by the LFA. The preliminary data showed that the LFA has high sensitivity (90 %) and specificity (100 %). When we used high responsive cat sera (i.e. sera that have optical density > 0.5 with ELISA) the sensitivity value reached 100 %. These results showed that rGRA1 protein is a good candidate to develop a LFA for rapid diagnosis of toxoplasmosis in cats., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Hepatozoon spp. are an apicomplexan protozoan parasites that infect vertebrates including mammals, marsupials, birds, reptiles, and amphibians. Among Hepatozoon species, H. canis and H. felis are causative agents of hepatozoonosis in dogs and cats, respectively and have veterinary importance. This study aimed to determine the prevalence of Hepatozoon spp. in stray cats living in İzmir and investigate genetic diversity among positive samples. To achieve this aim, the prevalence of Hepatozoon spp. 18S rRNA gene was screened by PCR in DNA samples extracted from blood samples of stray cats (n = 1012). Then, Hepatozoon-positive samples were sequenced and the generated data were used for species identification, phylogenetic and haplotype analyses. According to the results, among the samples screened, 2.37 % (24/1012) of them were found to be Hepatozoon-positive, and of these positive samples, 18 (18/24; 75 %) were successfully sequenced. BLAST and phylogenetic analyses revealed that all of these samples were H. felis. Also, phylogenetic analysis showed that H. felis samples were genotype I. Within H. felis samples isolated from cats living in different countries/regions, 9 haplotypes were detected and among these haplotypes, H-1 was found to be prevalent (n = 20 H. felis isolates). In conclusion, this study showed that the prevalence of Hepatozoon spp. was low in stray cats analyzed. Also, H. felis genotype I was predominant in comparison to other Hepatozoon species., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The phylum Microsporidia contains obligate single celled parasites that can infect many vertebrate hosts including humans. Enterocytozoon bieneusi is considered as the most diagnosed species in humans. E. bieneusi has also been detected in many animals such as cats, dogs and cattle. Among these animals, cats are carriers of type D and IV which are the most common human pathogenic genotypes of E. bieneusi. In Türkiye, the prevalence of E. bieneusi in stray cats is not well known. Therefore, in this study, the molecular prevalence of E. bieneusi in stray cats (n = 339) was determined by Real-Time PCR targeting ribosomal DNA ITS (internal transcribed spacer) region of E. bieneusi. Initially, the analytical sensitivity of Real-Time PCR was determined by a plasmid control and then E. bieneusi DNA was investigated in fecal samples of stray cats. The results showed that the analytical sensitivity of Real-Time PCR targeting ITS region of E. bieneusi was ≤1 copy plasmid/reaction. Analysis of fecal samples revealed that the molecular prevalence of E. bieneusi was 50.15% (170/339). Overall, these results showed that the Real-Time PCR successfully detected E. bieneusi in cat's fecal samples and stray cats can be an important source for transmission of E. bieneusi to humans and other animals., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Toxoplasma gondii ( T. gondii ) that can infect most warm-blooded animals and humans, is an obligate intracellular apicomplexan parasite with a wide host range. About one-third of the world's population is infected with this parasite. While toxoplasmosis progresses asymptomatically in individuals with a strong immune system, it can cause serious clinical manifestations and death in immunocompromised individuals. The parasite is transmitted to humans through the consumption of water and food contaminated with cat feces, as well as raw or undercooked animal products, congenital infection and blood/organ transplantation. Additionally, T. gondii is often observed in farm animals such as sheep and goats. Clinical manifestations and abortions caused by T. gondii in sheep and goats lead to enormous economic loss worldwide. There is a commercial vaccine against T. gondii , called Toxovax (MSD, New Zealand) that can only be used in sheep. For these reasons, there is a need for innovative T. gondii vaccine that is harmless, easily produced, which can prevent losses and be used in all living things. Advances in immunology, molecular biology, genetic, biotechnology and proteomics bring new perspectives to vaccine studies. Studies in innovative vaccine studies against T. gondii have accelerated with the discovery of new antigens by in vitro screenings, and bioinformatic analyzes, the use of various expression systems and new adjuvant types. Recombinant protein vaccines are biotechnological vaccines that are frequently preferred due to their rapid and easy production in various expression systems, availability of very and high purity products, ease of manipulation and stimulation of both cellular and humoral immune responses. Recombinant protein vaccines, developed by biotechnological methods, are promising tools for providing a protective immune response against toxoplasmosis. In this review, an overview of the parasite complex life cycle, its pathogenesis, humoral and cellular immune responses in the host, and recombinant protein vaccine studies developed against the parasite are presented.

The cat flea "Ctenocephalides felis" has veterinary and medical importance since it is a vector for numerous important pathogens. In this study, a total of 249 flea samples were collected from goats bred in eight different farms (located in İzmir and Şanlıurfa provinces of Turkey) and morphologically identified under microscopy. Later, the genetic diversity was investigated in 117 of C. felis samples that were morphologically identified by sequencing the mitochondrial cox1 gene, followed by phylogenetic tree, haplotype, genetic differentiation and gene flow analyses. In addition, Rickettsia spp. and Bartonella spp. which are zoonoses were screened in 27 pools comprising 249 flea samples by PCR. The phylogenetic tree showed that 117 flea samples were clustered in Clade 1 together with isolates from Australia, New Zealand, the Czech Republic, and India. Four haplotypes (haplotypes I, II, III and IV) were detected within the C. felis species. The most prevalent haplotype was haplotype I (57/117; 48.7 %). Among the population of flea samples in İzmir and Şanlıurfa, the Fst and Nm values were 0.16261 and 2.57, respectively, indicating a moderate genetic differentiation and high gene flow. Rickettsia spp. was detected in four of C. felis pool samples whereas Bartonella spp. was detected in 25 of them. BLAST analysis identified R. raoultii as well as B. henselae and B. elizabethae. In conclusion, the findings showed that C. felis samples collected from goats in Turkey were classified within Clade 1 representing four different haplotypes with a moderate genetic diversity for the first time. Also, R. raoultii, B. henselae and B. elizabethae were demonstrated for the first time in cat flea samples collected in Turkey., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Toxoplasmosis is a global health problem affecting both human and animal populations. The lack of effective treatment makes the development of a vaccine against toxoplasmosis one of the main goals in the management of this disease. In our study, vaccine formulations containing the multistage recombinant antigens, rBAG1 + rGRA1 were developed with a combined adjuvant system consisting of chitosan and Salmonella Typhi porins in micro (MicroAS) and nanoparticulate (NanoAS) forms. BALB/c mice were immunized intraperitoneally with vaccine formulations two times at three-week intervals. Three weeks after the second vaccination, mice were challenged with 7-8 live tissue cysts of the virulent T. gondii PRU strain by oral gavage. Higher cellular uptake by macrophages and enhanced cellular (IFN-γ and I-4 in stimulated spleen cells) and humoral (IgG, IgG1, IgG2a) responses were obtained with the adjuvanted formulation, higher with microsystem when compared to that of nanosystem. Microsystem was found to stimulate Th1-polarized immune responses, whereasnon-adjuvanted antigens stimulated Th2-polarized immune response. The highest survival rate and reduction in cysts numbers and T. gondii DNA were obtained with the adjuvanted antigens.Our study showed that adjuvanted multistage recombinant vaccine systems increase theimmune response with strong protection againstT. gondii, more profoundly in microparticulate form., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Toxoplasma gondii ( T. gondii ) is an obligate intracellular parasite that can infect almost all warm-blooded animals, including humans, and one-third of the global population is thought to be infected with this parasite. Infection can occur through consumption of contaminated food, contact with an infected host, or congenital transmission. While toxoplasmosis is asemptomatic in people with a healthy immune system, it can cause severe infections in people with a suppressed immune system or with immunodeficiency. In addition to causing diseases in humans, it also causes infections in livestock and may result in stillbirth and abortion in sheep and goats. There is no 100% effective medicine or vaccination against the parasite that causes major clinical symptoms and financial losses. There is a need for an effective, safe, and durable vaccine that can provide protective immunity for use in humans and animals. Vaccination studies against toxoplasmosis have gathered speed since the 1990s. Today, studies can be carried out to develop effective and safe vaccines depending on the developments in molecular biology, biotechnology, and immunology. DNA vaccines are a promising vaccine platform against toxoplasmosis because they are easy to produce, they are safe, they do not need a cold chain, and they can stimulate both humoral and cellular immune responses. This review provides an overview of the complex life cycle, pathogenesis, and epidemiology of the parasite; the immune response that develops in the host against the infection it causes; and the DNA vaccines developed against toxoplasmosis and these vaccines.

Background: Bartonella spp. are vector-borne pathogens that cause zoonotic infections in humans. One of the most well-known of these is cat-scratch disease caused by Bartonella henselae and Bartonella clarridgeiae, with cats being the major reservoir for these two bacteria. Izmir, Turkey is home to many stray cats, but their potential role as a reservoir for the transmission of Bartonella to humans has not been investigated yet. Therefore, the aim of this study was to investigate the prevalence of Bartonella species and their genetic diversity in stray cats living in Izmir., Methods: Molecular prevalence of Bartonella spp. in stray cats (n = 1012) was investigated using a PCR method targeting the 16S-23S internal transcribed spacer gene (ITS), species identification was performed by sequencing and genetic diversity was evaluated by haplotype analysis., Results: Analysis of the DNA extracted from 1012 blood samples collected from stray cats revealed that 122 samples were Bartonella-positive, which is a molecular prevalence of 12.05% (122/1012; 95% confidence interval [CI] 10.1-14.2%). Among the Bartonella-positive specimens, 100 (100/122; 81.96%) were successfully sequenced, and B. henselae (45/100; 45%), B. clarridgeiae (29/100; 29%) and Bartonella koehlerae (26/100; 26%) were identified by BLAST and phylogenetic analyses. High genetic diversity was detected in B. clarridgeiae with 19 haplotypes, followed by B. henselae (14 haplotypes) and B. koehlerae (8 haplotypes)., Conclusions: This comprehensive study analyzing a large number of samples collected from stray cats showed that Bartonella species are an important source of infection to humans living in Izmir. In addition, high genetic diversity was detected within each Bartonella species., (© 2022. The Author(s).)

Close contact with infected animals is one of the main risk factors for zoonotic transmission of enteric protozoan parasite Blastocystis and thus, several animal species are being screened for the detection of the zoonotic subtypes. For this purpose, 22 fecal samples were collected from healthy cattle aged > 2 months and 39 fecal samples were also collected from cattle (aged <2 months) which are treated with TMP-SMX due to diarrhea. Later, Blastocystis sp. and subtypes were investigated by a PCR targeting the SSU rRNA gene and subsequently by sequencing. Among the 22 fecal samples collected from healthy cattle, Blastocystis was detected in 12 of them with a prevalence rate of 54.5 %. Among Blastocystis-positive samples, five different subtypes (ST3, ST5, ST10, ST12, and ST13) were detected. The predominant subtype was ST10 (allele 152) with a prevalence rate of 50 % (6/12). In the other group treated with TMP-SMX due to diarrhea, Blastocystis was detected in only one (2.56 %;1/39) fecal sample and its subtype was ST1 (allele 2). High prevalence of Blastocystis as well as predominance of ST10 (allele 152) were detected in healthy cattle. The identification of zoonotic ST1, ST3, ST5 and ST12 subtypes among the detected subtypes with a high prevalence (46.1 %; 6/13) showed the importance of cattle as a source for transmission of Blastocystis to humans. It was observed that the efficiency of TMP-SMX on the clearance of Blastocystis in cattle was very strong. Moreover, to our knowledge, this is the first study detecting Blastocystis ST13 subtype in the cattle., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Discovery of new Toxoplasma gondii serotyping epitopes is important due to reports showing the influence of genotype on the severity of toxoplasmosis. In Turkey, genotypes belonging to type II, type III and Africa 1 lineages were mainly detected. The present study focused on to find out epitopes with high discriminative capacity to serotype these genotypes using well characterized strains isolated from Turkey., Methods: To meet this objective, GRA6 and GRA7 genes were sequenced from strains belonging to the type II, III and Africa 1 lineages, and B cell epitopes inside these sequences were predicted by Bcepred and additional docking analysis was performed with B cell receptor. Based on these analyses, 22 peptides harboring lineage specific epitopes were synthesized. Then, the serotyping potency of these peptides was tested using peptide ELISA and well categorized serum samples collected from stray cats infected with genotypes of the different lineages type II (n:9), III (n:1) and Africa 1 (n:1). As a result of peptide-ELISA, a serotyping schema was constructed with peptides that show high discriminative capacity and this assay was validated by sera collected from humans after an outbreak (n:30) and mother/newborn pair sera (n:3). Later, the validated serotyping schema was used to serotype a larger group of human (n:38) and cat (n:24) sera., Results: Among 22 peptides, GRA6II/c, GRA7III/d, and GRA6 Africa 1/b epitopes have shown discriminative capacity. During the validation of peptide-ELISA, the serotype of toxoplasmosis outbreak and mother/newborn cases were detected to be serotype II. Moreover, the analyses in a larger group showed that serotype II was prevalent in humans and stray cats., Conclusions: Overall, the results showed that the serotyping schema could be successfully used to serotype T. gondii infections caused by type II, III and Africa 1 genotype., (© 2022. The Author(s).)

Diarrhea caused by parasitic agents is common in neonatal calves and leads to significant economic losses in cattle farms worldwide. Cryptosporidium spp. is one of the most frequently detected parasitic agents causing diarrhea in neonatal calves. The aim of this study was to investigate the presence of Cryptosporidium spp. on a dairy farm which a has major diarrhea problem. Samples were collected from calves, cows, drinking bowls, and two different artesian water sources, as well as from the environment. All fecal samples were investigated using Kinyoun acid-fast stained slides and real-time PCR targeting the Cryptosporidium spp. COWP gene. In addition, species identification was performed by nested PCR targeting the Cryptosporidium spp. COWP gene and sequencing. Cryptosporidium spp. was detected in 11 calves (30.55%; 11/36) by real-time PCR and the cows were negative. Among real-time PCR positive samples, only five were also found positive by microscopy. Moreover, Cryptosporidium spp. was found in one of the two artesian water sources and five environmental samples by real-time PCR. Among these positive samples, eight were sequenced. According to the RFLP pattern, BLAST and, phylogenetic analyses, all sequenced samples were Cryptosporidium parvum. These findings show the importance of C. parvum as a cause of calf diarrhea on dairy farms., (Copyright© by the Polish Academy of Sciences.)

Blastocystis sp. is one of the most frequently detected intestinal parasites in humans and can inhabit a wide range of animals. Close contact with animals is one of the transmission factors of Blastocystis sp. infection in humans. In this study, we aimed to investigate the molecular prevalence and subtypes of Blastocystis sp. in stray cats living in İzmir, Turkey. The PCR target- ing the barcode region in the SSU rRNA gene was performed with DNA samples isolated from feces (n:465) to investigate the presence of Blastocystis sp. PCR positive samples were sequen- ced for subtyping analysis. Among the samples analyzed, Blastocystis sp. DNA was detected in 17 (3.65%) of them and sequence data were obtained from only seven isolates. Phylogenetic analysis showed that seven Blastocystis sp. isolates clustered with the reference Blastocystis ST4 isolates. Similarity rates were between 83.22% and 99.25%. In addition, Blastocystis database results confirmed that all of these were "allele 42" corresponding to ST4. As a result, the present study shows for the first time the presence of "ST4 allele 42", the prevalent subtype in humans, in stray cats in İzmir, Turkey. This finding supports the notion that stray cats can be a source of Blastocystis sp. infection in humans., (Copyright© by the Polish Academy of Sciences.)

Background: The emergence of tick-borne disease is increasing because of the effects of the temperature rise driven by global warming. In Turkey, 19 pathogens transmitted by ticks to humans and animals have been reported. Based on this, this study aimed to investigate tick-borne pathogens including Hepatozoon spp., Theileria spp., Babesia spp., Anaplasma spp., Borrelia spp., and Bartonella spp. in tick samples (n = 110) collected from different hosts (dogs, cats, cattle, goats, sheep, and turtles) by molecular methods., Methods: To meet this objective, ticks were identified morphologically at the genus level by microscopy; after DNA isolation, each tick sample was identified at the species level using the molecular method. Involved pathogens were then investigated by PCR method., Results: Seven different tick species were identified including Rhipicephalus sanguineus, R. turanicus, R. bursa, Hyalomma marginatum, H. anatolicum, H. aegyptium, and Haemaphysalis erinacei. Among the analyzed ticks, Hepatozoon spp., Theileria spp., Babesia spp., and Anaplasma spp. were detected at rates of 6.36%, 16.3%, 1.81%, and 6.36%, respectively while Borrelia spp. and Bartonella spp. were not detected. Hepatozoon spp. was detected in R. sanguineus ticks while Theileria spp., Babesia spp., and Anaplasma spp. were detected in R. turanicus and H. marginatum. According to the results of sequence analyses applied for pathogen positive samples, Hepatozoon canis, Theileria ovis, Babesia caballi, and Anaplasma ovis were identified., Conclusion: Theileria ovis and Anaplasma ovis were detected for the first time to our knowledge in H. marginatum and R. turanicus collected from Turkey, respectively. Also, B. caballi was detected for the first time to our knowledge in ticks in Turkey.

Background: Cytidine monophospho-n-acetylneuraminic acid hydroxylase (CMAH) gene associated with blood groups in cats encodes CMAH enzyme that converts Neu5Ac to Neu5Gc. Although variations in CMAH gene of pedigree cats have been revealed, the presence/lack of them in non-pedigree stray cats is unknown. Therefore, the present study aimed to investigate the variations in CMAH gene and the quantity of Neu5Ac and Neu5Gc on erythrocytes of non-pedigree stray cats (n:12) living in İzmir, Turkey. Also, the frequency of blood types was determined in 76 stray cats including 12 cats that were used for CMAH and Neu5A/Neu5Gc analysis., Results: In total, 14 SNPs were detected in 5'UTR as well as in exon 2, 4, 9, 10, 11 and 12 of CMAH gene. Among these SNPs, -495 C > T in 5'UTR was detected for the first time as heterozygous in type A and AB cats, and homozygous and heterozygous in type B cats. The remaining 13 that have been detected in previous studies were also found as homozygous or heterozygous. Both Neu5Gc and Neu5Ac were detected in type A and AB cats. In type B cats, only Neu5Ac was detected. Among two type AB cats, the level of Neu5Ac was found higher in cat carrying heterozygous form (T/C) of 1392T > C. The prevalence of type B cats (67.1 %) was higher than others., Conclusions: The presence of a new SNP as well as previous SNPs indicates that more variations can be found in stray cats with a more comprehensive study in the future. Also, the high prevalence of type B cats demonstrates the possible risk of neonatal isoerythrolysis among stray cats living in İzmir, Turkey.

In the genome of SARS-CoV-2, the 5'-terminus encodes a polyprotein, which is further cleaved into 15 non-structural proteins whereas the 3' terminus encodes four structural proteins and eight accessory proteins. Among these 27 proteins, the present study aimed to discover likely antigenic proteins and epitopes to be used for the development of a vaccine or serodiagnostic assay using an in silico approach. For this purpose, after the full genome analysis of SARS-CoV-2 Wuhan isolate and variant proteins that are detected frequently, surface proteins including spike, envelope, and membrane proteins as well as proteins with signal peptide were determined as probable vaccine candidates whereas the remaining were considered as possible antigens to be used during the development of serodiagnostic assays. According to results obtained, among 27 proteins, 26 of them were predicted as probable antigen. In 26 proteins, spike protein was selected as the best vaccine candidate because of having a signal peptide, negative GRAVY value, one transmembrane helix, moderate aliphatic index, a big molecular weight, a long-estimated half-life, beta wrap motifs as well as having stable, soluble and non-allergic features. In addition, orf7a, orf8, and nsp-10 proteins with signal peptide were considered as potential vaccine candidates. Nucleocapsid protein and a highly antigenic GGDGKMKD epitope were identified as ideal antigens to be used in the development of serodiagnostic assays. Moreover, considering MHC-I alleles, highly antigenic KLNDLCFTNV and ITLCFTLKRK epitopes can be used to develop an epitope-based peptide vaccine.

Fleas are ectoparasites of mammals and birds. In livestock such as sheep and goat, flea bites cause many clinical signs. Several types of insecticides including pyrethroids are used to struggle against fleas. The widespread use of these insecticides causes an increase in the number of resistant individuals in flea populations. T929V and L1014F mutations corresponding to pyrethroid resistance have been found in the para gene of cat fleas. We aimed to investigate T929V and L1014F mutations in flea samples (n:162) collected from goats in seven different farms where cypermethrin, a synthetic pyrethroid, had been used intensively. To achieve this aim, collected flea samples were morphologically identified under a stereo microscope and DNA isolation was conducted by HotSHOT method. Later, a bi-PASA targeting the para gene was applied to identify both mutations in corresponding samples. According to the results obtained, all fleas were Ctenocephalides felis. Frequencies of T929V and L1014F mutations in fleas were 92.6% (150/162) and 95.7% (155/162), respectively. In conclusion, the frequency of mutations related to pyrethroid resistance was very high in the fleas collected from all the farms and it was thought that the high frequency of these mutations can be attributed to intensive use of pyrethroids.

Ticks are obligate hematophagous ectoparasites as well as mechanical and biological vectors of a wide variety of microbial pathogens. To date, 19 tick-borne diseases have been reported from Turkey. In this study, ticks collected from Aydın, İzmir and Şanlıurfa provinces of Turkey were identified using morphological and molecular methods. After the presence of bacterial DNA was checked, Rickettsia spp. and Francisella tularensis were investigated in bacterial DNA-positive tick specimens by PCR. Furthermore, amplicons belonging to tick specimens and positive bacterial samples were sequenced and processed for BLAST, alignment and phylogenetic analysis. As a result, seven tick species were identified: Rhipicephalus sanguineus, Rh. bursa, Rh. turanicus, Hyalomma marginatum, Hy. aegyptium, Hy. anatolicum and Haemaphysalis erinacei. Fifty-five tick specimens tested positive for bacterial DNA and among them, rickettsial DNA was found in five ticks (infection rate = 9.1%) belonging to Hy. marginatum, Hy. aegyptium, Rh. bursa and Rh. turanicus. Of the five Rickettsia-positive ticks, three contained Rickettsia aeschlimannii, one Ri. massiliae and one an unidentified Rickettsia sp. No Francisella tularensis DNA was detected. Sequence analysis of the ompB gene indicated two novel single nucleotide polymorphisms (SNP) in two different Ri. aeschlimannii strains and two novel SNPs as well as a novel insertion (GACGGT) were found in Rickettsia sp. This study indicated the presence of polymorphic Rickettsia species in ticks from Turkey.

Toxoplasma gondii, one of the extensively studied Apicomplexan parasites, is prevalent worldwide in animals and humans. Apart from its nuclear genome, T. gondii contains an apicoplast genome in 35 kb length which is originated from a secondary endosymbiotic event. In this study, we aimed to investigate the antigenic potential of apicoplast genome encoded proteins (n:28) of T. gondii using in silico analysis. For this purpose, proteins were primarily predicted to reveal antigenic probability and then, several bioinformatics analyses were applied for all predicted antigenic apicoplast proteins to analyze physico-chemical parameters, subcellular localization and transmembrane domain. Also, further prediction analyses including structural, B cell and MHC-I/II epitope sites as well as post-translational modifications were performed for antigenic proteins that have a signal peptide or a high antigenicity value. Of the 28 apicoplast proteins, 19 were predicted as probable antigen. Among antigenic proteins, ribosomal protein S5, L11 and S2 were predicted to have signal peptide whereas ribosomal protein L36 and S17 were predicted to have a significantly high antigenicity value (P < 0.05). In addition, ribosomal protein S5, L11, S2, L36 and S17 were predicted to have a lot of epitopes which have low IC50 and percentile rank value indicating a strong binding among epitopes and MHC-I/II alleles, and post-translational modifications such as N-linked glycosylation, acetylation and phosphorylation. To the best of authors' knowledge this is the first study to show the antigenic potential and other properties of apicoplast-derived proteins of T. gondii., (Copyright © 2019 Elsevier Ltd. All rights reserved.)