Limits...
HSP70 domain II of Mycobacterium tuberculosis modulates immune response and protective potential of F1 and LcrV antigens of Yersinia pestis in a mouse model.

Batra L, Verma SK, Nagar DP, Saxena N, Pathak P, Pant SC, Tuteja U - PLoS Negl Trop Dis (2014)

Bottom Line: A significant difference was noticed in the expression level of IL-2, IFN-γ and TNF-α in splenocytes of immunized animals.We investigated whether the F1, LcrV and HSP70(II) antigens alone or in combination can effectively protect immunized animals from any histopathological changes.A significant difference was observed in the expression of IL-2, IFN-γ, TNF-α, and CD4+/CD8+ T cells secreting IFN-γ in the F1+LcrV+HSP70(II) vaccinated group in comparison to the F1+LcrV vaccinated group.

View Article: PubMed Central - PubMed

Affiliation: Microbiology Division, Defence Research & Development Establishment, Gwalior, India.

ABSTRACT
No ideal vaccine exists to control plague, a deadly dangerous disease caused by Yersinia pestis. In this context, we cloned, expressed and purified recombinant F1, LcrV antigens of Y. pestis and heat shock protein70 (HSP70) domain II of M. tuberculosis in E. coli. To evaluate the protective potential of each purified protein alone or in combination, Balb/C mice were immunized. Humoral and cell mediated immune responses were evaluated. Immunized animals were challenged with 100 LD50 of Y. pestis via intra-peritoneal route. Vaccine candidates i.e., F1 and LcrV generated highly significant titres of anti-F1 and anti-LcrV IgG antibodies. A significant difference was noticed in the expression level of IL-2, IFN-γ and TNF-α in splenocytes of immunized animals. Significantly increased percentages of CD4+ and CD8+ T cells producing IFN-γ in spleen of vaccinated animals were observed in comparison to control group by flow cytometric analysis. We investigated whether the F1, LcrV and HSP70(II) antigens alone or in combination can effectively protect immunized animals from any histopathological changes. Signs of histopathological lesions noticed in lung, liver, kidney and spleen of immunized animals on 3rd day post challenge whereas no lesions in animals that survived to day 20 post-infection were observed. Immunohistochemistry showed bacteria in lung, liver, spleen and kidney on 3rd day post-infection whereas no bacteria was observed on day 20 post-infection in surviving animals in LcrV, LcrV+HSP70(II), F1+LcrV, and F1+LcrV+HSP70(II) vaccinated groups. A significant difference was observed in the expression of IL-2, IFN-γ, TNF-α, and CD4+/CD8+ T cells secreting IFN-γ in the F1+LcrV+HSP70(II) vaccinated group in comparison to the F1+LcrV vaccinated group. Three combinations that included LcrV+HSP70(II), F1+LcrV or F1+LcrV+HSP70(II) provided 100% protection, whereas LcrV alone provided only 75% protection. These findings suggest that HSP70(II) of M. tuberculosis can be a potent immunomodulator for F1 and LcrV containing vaccine candidates against plague.

Show MeSH

Related in: MedlinePlus

Determination of survival of Balb/C mice infected with Y. pestis.The immunized and PBS control groups (8 mice/group) were challenged with 100 LD50 of Y. pestis (S1 strain). The protective efficacy of vaccine candidate alone or in mixture of antigens was determined by Kaplan Meier's method to compare percentage survivals (****P<0.0001, ***P<0.001).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4256173&req=5

pntd-0003322-g006: Determination of survival of Balb/C mice infected with Y. pestis.The immunized and PBS control groups (8 mice/group) were challenged with 100 LD50 of Y. pestis (S1 strain). The protective efficacy of vaccine candidate alone or in mixture of antigens was determined by Kaplan Meier's method to compare percentage survivals (****P<0.0001, ***P<0.001).

Mentions: In order to compare the protective efficacy, the immunized animals were challenged with 100 LD50 of virulent Y. pestis including control group. Survivals of the animals were monitored for 30 days post challenge (Figure 6). Three vaccine combinations [LcrV+HSP70(II), F1+HSP70(II), F1+LcrV+HSP70(II)] resulted in 100% protection from the Y. pestis challenged mice (P<0.0001), whereas the LcrV and F1+HSP70(II) vaccinated mice were only 75% (P<0.001) and 12.5% protected, respectively. There was no protection observed in control, HSP70(II) and F1 groups. Y. pestis was recovered from the spleen, lung, liver and kidney of dead animals which succumbed to the challenge and identified by the growth on blood agar. Survived animals were sacrificed 30 days post-challenge, and autopsied for any bacterial presence in their organs like spleen, lung, liver and kidney. Vaccinated animals that survived the challenge appeared to clear Y. pestis from the mice since no growth was observed on blood agar plates from spleens, lungs, livers, and kidneys.


HSP70 domain II of Mycobacterium tuberculosis modulates immune response and protective potential of F1 and LcrV antigens of Yersinia pestis in a mouse model.

Batra L, Verma SK, Nagar DP, Saxena N, Pathak P, Pant SC, Tuteja U - PLoS Negl Trop Dis (2014)

Determination of survival of Balb/C mice infected with Y. pestis.The immunized and PBS control groups (8 mice/group) were challenged with 100 LD50 of Y. pestis (S1 strain). The protective efficacy of vaccine candidate alone or in mixture of antigens was determined by Kaplan Meier's method to compare percentage survivals (****P<0.0001, ***P<0.001).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4256173&req=5

pntd-0003322-g006: Determination of survival of Balb/C mice infected with Y. pestis.The immunized and PBS control groups (8 mice/group) were challenged with 100 LD50 of Y. pestis (S1 strain). The protective efficacy of vaccine candidate alone or in mixture of antigens was determined by Kaplan Meier's method to compare percentage survivals (****P<0.0001, ***P<0.001).
Mentions: In order to compare the protective efficacy, the immunized animals were challenged with 100 LD50 of virulent Y. pestis including control group. Survivals of the animals were monitored for 30 days post challenge (Figure 6). Three vaccine combinations [LcrV+HSP70(II), F1+HSP70(II), F1+LcrV+HSP70(II)] resulted in 100% protection from the Y. pestis challenged mice (P<0.0001), whereas the LcrV and F1+HSP70(II) vaccinated mice were only 75% (P<0.001) and 12.5% protected, respectively. There was no protection observed in control, HSP70(II) and F1 groups. Y. pestis was recovered from the spleen, lung, liver and kidney of dead animals which succumbed to the challenge and identified by the growth on blood agar. Survived animals were sacrificed 30 days post-challenge, and autopsied for any bacterial presence in their organs like spleen, lung, liver and kidney. Vaccinated animals that survived the challenge appeared to clear Y. pestis from the mice since no growth was observed on blood agar plates from spleens, lungs, livers, and kidneys.

Bottom Line: A significant difference was noticed in the expression level of IL-2, IFN-γ and TNF-α in splenocytes of immunized animals.We investigated whether the F1, LcrV and HSP70(II) antigens alone or in combination can effectively protect immunized animals from any histopathological changes.A significant difference was observed in the expression of IL-2, IFN-γ, TNF-α, and CD4+/CD8+ T cells secreting IFN-γ in the F1+LcrV+HSP70(II) vaccinated group in comparison to the F1+LcrV vaccinated group.

View Article: PubMed Central - PubMed

Affiliation: Microbiology Division, Defence Research & Development Establishment, Gwalior, India.

ABSTRACT
No ideal vaccine exists to control plague, a deadly dangerous disease caused by Yersinia pestis. In this context, we cloned, expressed and purified recombinant F1, LcrV antigens of Y. pestis and heat shock protein70 (HSP70) domain II of M. tuberculosis in E. coli. To evaluate the protective potential of each purified protein alone or in combination, Balb/C mice were immunized. Humoral and cell mediated immune responses were evaluated. Immunized animals were challenged with 100 LD50 of Y. pestis via intra-peritoneal route. Vaccine candidates i.e., F1 and LcrV generated highly significant titres of anti-F1 and anti-LcrV IgG antibodies. A significant difference was noticed in the expression level of IL-2, IFN-γ and TNF-α in splenocytes of immunized animals. Significantly increased percentages of CD4+ and CD8+ T cells producing IFN-γ in spleen of vaccinated animals were observed in comparison to control group by flow cytometric analysis. We investigated whether the F1, LcrV and HSP70(II) antigens alone or in combination can effectively protect immunized animals from any histopathological changes. Signs of histopathological lesions noticed in lung, liver, kidney and spleen of immunized animals on 3rd day post challenge whereas no lesions in animals that survived to day 20 post-infection were observed. Immunohistochemistry showed bacteria in lung, liver, spleen and kidney on 3rd day post-infection whereas no bacteria was observed on day 20 post-infection in surviving animals in LcrV, LcrV+HSP70(II), F1+LcrV, and F1+LcrV+HSP70(II) vaccinated groups. A significant difference was observed in the expression of IL-2, IFN-γ, TNF-α, and CD4+/CD8+ T cells secreting IFN-γ in the F1+LcrV+HSP70(II) vaccinated group in comparison to the F1+LcrV vaccinated group. Three combinations that included LcrV+HSP70(II), F1+LcrV or F1+LcrV+HSP70(II) provided 100% protection, whereas LcrV alone provided only 75% protection. These findings suggest that HSP70(II) of M. tuberculosis can be a potent immunomodulator for F1 and LcrV containing vaccine candidates against plague.

Show MeSH
Related in: MedlinePlus