Limits...
Doubly Phosphorylated Peptide Vaccines to Protect Transgenic P301S Mice against Alzheimer's Disease Like Tau Aggregation.

Richter M, Mewes A, Fritsch M, Krügel U, Hoffmann R, Singer D - Vaccines (Basel) (2014)

Bottom Line: The effectiveness of the immunization was surveyed by evaluating the animal behavior, as well as the pathology in the brain by biochemical and histochemical techniques.Additionally, they performed significantly better in rotarod and beam walk tests at the age of 20 weeks, indicating that the disease development was slowed down.In conclusion, the data provide strong evidence that active immune therapies can reduce toxic effects of deposits formed in AD.

View Article: PubMed Central - PubMed

Affiliation: Institute of Bioanalytical Chemistry, Faculty of Chemistry and Mineralogy, Universität Leipzig, Deutscher Platz 5, Leipzig 04103, Germany. monique_richter@gmx.de.

ABSTRACT
Intracellular neurofibrillary tangles and extracellular senile plaques are potential targets for active and passive immunotherapies. In this study we used the transgenic mouse model P301S for active immunizations with peptide vaccines composed of a double phosphorylated tau neoepitope (pSer202/pThr205, pThr212/pSer214, pThr231/pSer235) and an immunomodulatory T cell epitope from the tetanus toxin or tuberculosis antigen Ag85B. Importantly, the designed vaccine combining Alzheimer's disease (AD) specific B cell epitopes with foreign (bacterial) T cell epitopes induced fast immune responses with high IgG₁ titers after prophylactic immunization that subsequently decreased over the observation period. The effectiveness of the immunization was surveyed by evaluating the animal behavior, as well as the pathology in the brain by biochemical and histochemical techniques. Immunized mice clearly lived longer with reduced paralysis than placebo-treated mice. Additionally, they performed significantly better in rotarod and beam walk tests at the age of 20 weeks, indicating that the disease development was slowed down. Forty-eight weeks old vaccinated mice passed the beam walk test significantly better than control animals, which together with the increased survival rates undoubtedly prove the treatment effect. In conclusion, the data provide strong evidence that active immune therapies can reduce toxic effects of deposits formed in AD.

No MeSH data available.


Related in: MedlinePlus

Normalized phospho-tau contents in brain homogenates of placebo-treated P301S mice (n = 5–6, ♦) and P301S mice immunized with Tau199–208[pS202/pT205] (n = 3‑5, ), Tau209–217[pT212/pS214] (n = 5–6, ), and Tau229–237[pT231/pS235] (n = 5–6, ) at 32 weeks (upper row) and 48 weeks (lower row) of age obtained from immunoblots. Shown are the relative ratios of phospho-tau (mAbs AT8, AT100, and AT180) to total tau (mAb Tau5) in percent arranged according to the temporal occurrence of the phospho-tau epitopes (pT231/pS235—early, pT212/pS214—intermediate, pS202/pT205—late).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4494214&req=5

vaccines-02-00601-f005: Normalized phospho-tau contents in brain homogenates of placebo-treated P301S mice (n = 5–6, ♦) and P301S mice immunized with Tau199–208[pS202/pT205] (n = 3‑5, ), Tau209–217[pT212/pS214] (n = 5–6, ), and Tau229–237[pT231/pS235] (n = 5–6, ) at 32 weeks (upper row) and 48 weeks (lower row) of age obtained from immunoblots. Shown are the relative ratios of phospho-tau (mAbs AT8, AT100, and AT180) to total tau (mAb Tau5) in percent arranged according to the temporal occurrence of the phospho-tau epitopes (pT231/pS235—early, pT212/pS214—intermediate, pS202/pT205—late).

Mentions: Phosphorylation degrees of the human tau mutant at positions 231/235, 212/214 and 202/205, representing an early, an intermediate and a late phosphorylation event [29,30], were judged in immunoblots after SDS-PAGE by normalizing the relative band intensities obtained with mAbs AT8, AT100, and AT180, respectively, to mAb Tau5 (total tau). It should be noted that the normalized intensities allow only to judge higher or lower phosphorylation degrees of a given epitope (represented by one mAb) among the animal groups, but do not among the three different epitopes. Expectedly, immunoblots of non-transgenic control mice did not display any band in the area where the human tau isoform 412 was detected, whereas transgenic mice displayed intense tau and phospho-tau bands (Figure S2). In general, immunized and non-immunized 48 weeks old mice had higher phosphorylation-degrees than 32-week-old mice on top of the tau expression levels that increased also with age (Figure 5). Although the changes of the phosphorylation degrees among the different groups were not statistically significant, which was attributed to the heterogeneity among the animals of one group and the relatively bad quantification characteristics of immunoblots, there are few interesting trends obvious. MAb AT8 indicated an increasing phosphorylation degree from 32 to 48 weeks in the placebo group, whereas the levels remained stable in the immunized groups and thus were lower than the placebo group, which was even significant for mice immunized with the corresponding epitope Tau199–208[pS202/pT205] (one-tailed Mann-Whitney test). A similar but less pronounced trend was visible for mAb AT100, but not for mAb AT180. The latter mAb, however, recognizes also tau mono-phosphorylated at Thr231 and thus does not correctly stain the targeted double phosphorylated tau version.


Doubly Phosphorylated Peptide Vaccines to Protect Transgenic P301S Mice against Alzheimer's Disease Like Tau Aggregation.

Richter M, Mewes A, Fritsch M, Krügel U, Hoffmann R, Singer D - Vaccines (Basel) (2014)

Normalized phospho-tau contents in brain homogenates of placebo-treated P301S mice (n = 5–6, ♦) and P301S mice immunized with Tau199–208[pS202/pT205] (n = 3‑5, ), Tau209–217[pT212/pS214] (n = 5–6, ), and Tau229–237[pT231/pS235] (n = 5–6, ) at 32 weeks (upper row) and 48 weeks (lower row) of age obtained from immunoblots. Shown are the relative ratios of phospho-tau (mAbs AT8, AT100, and AT180) to total tau (mAb Tau5) in percent arranged according to the temporal occurrence of the phospho-tau epitopes (pT231/pS235—early, pT212/pS214—intermediate, pS202/pT205—late).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4494214&req=5

vaccines-02-00601-f005: Normalized phospho-tau contents in brain homogenates of placebo-treated P301S mice (n = 5–6, ♦) and P301S mice immunized with Tau199–208[pS202/pT205] (n = 3‑5, ), Tau209–217[pT212/pS214] (n = 5–6, ), and Tau229–237[pT231/pS235] (n = 5–6, ) at 32 weeks (upper row) and 48 weeks (lower row) of age obtained from immunoblots. Shown are the relative ratios of phospho-tau (mAbs AT8, AT100, and AT180) to total tau (mAb Tau5) in percent arranged according to the temporal occurrence of the phospho-tau epitopes (pT231/pS235—early, pT212/pS214—intermediate, pS202/pT205—late).
Mentions: Phosphorylation degrees of the human tau mutant at positions 231/235, 212/214 and 202/205, representing an early, an intermediate and a late phosphorylation event [29,30], were judged in immunoblots after SDS-PAGE by normalizing the relative band intensities obtained with mAbs AT8, AT100, and AT180, respectively, to mAb Tau5 (total tau). It should be noted that the normalized intensities allow only to judge higher or lower phosphorylation degrees of a given epitope (represented by one mAb) among the animal groups, but do not among the three different epitopes. Expectedly, immunoblots of non-transgenic control mice did not display any band in the area where the human tau isoform 412 was detected, whereas transgenic mice displayed intense tau and phospho-tau bands (Figure S2). In general, immunized and non-immunized 48 weeks old mice had higher phosphorylation-degrees than 32-week-old mice on top of the tau expression levels that increased also with age (Figure 5). Although the changes of the phosphorylation degrees among the different groups were not statistically significant, which was attributed to the heterogeneity among the animals of one group and the relatively bad quantification characteristics of immunoblots, there are few interesting trends obvious. MAb AT8 indicated an increasing phosphorylation degree from 32 to 48 weeks in the placebo group, whereas the levels remained stable in the immunized groups and thus were lower than the placebo group, which was even significant for mice immunized with the corresponding epitope Tau199–208[pS202/pT205] (one-tailed Mann-Whitney test). A similar but less pronounced trend was visible for mAb AT100, but not for mAb AT180. The latter mAb, however, recognizes also tau mono-phosphorylated at Thr231 and thus does not correctly stain the targeted double phosphorylated tau version.

Bottom Line: The effectiveness of the immunization was surveyed by evaluating the animal behavior, as well as the pathology in the brain by biochemical and histochemical techniques.Additionally, they performed significantly better in rotarod and beam walk tests at the age of 20 weeks, indicating that the disease development was slowed down.In conclusion, the data provide strong evidence that active immune therapies can reduce toxic effects of deposits formed in AD.

View Article: PubMed Central - PubMed

Affiliation: Institute of Bioanalytical Chemistry, Faculty of Chemistry and Mineralogy, Universität Leipzig, Deutscher Platz 5, Leipzig 04103, Germany. monique_richter@gmx.de.

ABSTRACT
Intracellular neurofibrillary tangles and extracellular senile plaques are potential targets for active and passive immunotherapies. In this study we used the transgenic mouse model P301S for active immunizations with peptide vaccines composed of a double phosphorylated tau neoepitope (pSer202/pThr205, pThr212/pSer214, pThr231/pSer235) and an immunomodulatory T cell epitope from the tetanus toxin or tuberculosis antigen Ag85B. Importantly, the designed vaccine combining Alzheimer's disease (AD) specific B cell epitopes with foreign (bacterial) T cell epitopes induced fast immune responses with high IgG₁ titers after prophylactic immunization that subsequently decreased over the observation period. The effectiveness of the immunization was surveyed by evaluating the animal behavior, as well as the pathology in the brain by biochemical and histochemical techniques. Immunized mice clearly lived longer with reduced paralysis than placebo-treated mice. Additionally, they performed significantly better in rotarod and beam walk tests at the age of 20 weeks, indicating that the disease development was slowed down. Forty-eight weeks old vaccinated mice passed the beam walk test significantly better than control animals, which together with the increased survival rates undoubtedly prove the treatment effect. In conclusion, the data provide strong evidence that active immune therapies can reduce toxic effects of deposits formed in AD.

No MeSH data available.


Related in: MedlinePlus