It is common knowledge that fecal microbiota is a primary source of Escherichia coli causing urinary tract infections (UTIs) via the fecal‐perineal‐urethral route. But, it is still unknown whether E. coli UTI is mainly caused by dominant fecal E. coli isolates (prevalence hypothesis) or the isolates that possess more virulence factors (special pathogenicity hypothesis). In the present study, the urine E. coli isolates of 30 women with UTI were compared with the fecal E. coli isolates of the same patients and healthy control individuals according to the phylogenetic group, virulence genotype, and antibiotic susceptibility pattern. The genetic relatedness of the isolates was specified and compared by pulsed‐field gel electrophoresis (PFGE). PFGE analysis showed that most patients (73.3%) had distinct urine isolates which were not similar to any of their fecal isolates. Based on the phylogenetic analysis, most of the urine and fecal isolates of healthy women were assigned to phylogenetic group B2, followed by D. The distribution of phylogenetic groups was significantly different between the urine and the fecal isolates of patients ( p < 0.05). The prevalence of fimH and ompT among urine isolates was significantly more than that among fecal isolates. The level of multidrug resistance was higher among urine isolates. Although more in‐depth researches are required, the present study could be supported by pathogenicity hypothesis. Furthermore, concerning the antibiotic resistance pattern among uropathogenic E. coli should be highly considered.
Mycobacterium avium subsp. paratuberculosis (MAP) is a causative agent of Johne’s disease in all ruminants worldwide. Economic problems in dairy cattle and sheep industries, public health concern, persistence of MAP in the environment and lack of effective vaccines mentioned necessity of research about various antigens to introduce as vaccine candidates. Based on MAP pathogenesis, it seems that research about the production of new recombinant proteins to stimulate cell-mediated immunity is helpful. This study describes successful expression and purification of a chimeric fusion protein which consists of Heparin-Binding Hemagglutinin Adhesin (HBHA) and high antigenic region of Fibronectin Attachment Protein (FAP-P). Triggered antigen-specific IFN-γ response of isolated PBMCs from immunized goats to rHBHA-FAP and all crude proteins of MAP (PPD), was measured by ELISA. Significant increases were observed in the IFN-γ production level of peripheral blood mononuclear cells (PBMCs) stimulated by constructed chimeric protein from rHBHA-FAP and PPD vaccinated goats. Antigen-specific gamma interferon (IFN-γ) secretion in positive group (immunized by PPD) against rHBHA-FAP and test group (immunized by rHBHA-FAP) against PPD, also statistically insignificant rises between stimulation with rHBHA-FAP and PPD, suggested the potential and specificity of our chimeric protein to stimulate cell mediated immunity against MAP. Collectively, these results demonstrate that rHBHA-FAP elicits a strong IFN-γ production in PBMC culture. Therefore, further studies of the present product as a candidate vaccine in naturally infected animals should be conducted, to analyze its potential.
Attenuated Salmonella strains offer an opportunity for delivering DNA vaccines to antigen-presenting cells. DNA vaccines trigger cellular immune responses, making them suitable for targeting intracellular pathogens, such as Mycobacterium avium subspecies paratuberculosis (MAP). Since whole organism MAP vaccines interfere with tuberculosis diagnosis, innovative vaccine technologies have been introduced to elicit an immune response targeting species-specific antigens. Fibronectin attachment protein (FAP), a MAP surface antigen that is species-specific, can induce cellular immune responses. The present study aims to explore the immunogenic potential of a mammalian expression plasmid encoding the fap-P gene of MAP within a mouse model, utilizing a Salmonella vector for oral immunization using a fluorescent assay and Western blot analysis. The results proved the ability of the constructed plasmid to stimulate the humoral immune response in mice. Moreover, fluorescence microscopy of splenocytes confirmed the successful delivery of the plasmid to the immune system at 24, 48, and 72 h following oral administration. It can be concluded that FAP-P could be considered a candidate for further investigation in the context of MAP vaccine development. Additionally, the use of Salmonella as a delivery system not only improves the efficacy of DNA vaccines but also helps in the preliminary evaluation of the antigens’ immunogenic properties.