TY - JOUR
T1 - Prototype Alzheimer's disease vaccine using the immunodominant B cell epitope from β-amyloid and promiscuous T cell epitope pan HLA DR-binding peptide
AU - Agadjanyan, Michael G.
AU - Ghochikyan, Anahit
AU - Petrushina, Irina
AU - Vasilevko, Vitaly
AU - Movsesyan, Nina
AU - Mkrtichyan, Mikayel
AU - Saing, Tommy
AU - Cribbs, David H.
PY - 2005/2/1
Y1 - 2005/2/1
N2 - Immunization of amyloid precursor protein transgenic mice with fibrillar β-amyloid (Aβ) prevents Alzheimer's disease (AD)-like neuropathology. The first immunotherapy clinical trial used fibrillar Aβ, containing the B and T cell self epitopes of Aβ, as the immunogen formulated with QS21 as the adjuvant in the vaccine. Unfortunately, the clinical trial was halted during the phase II stage when 6% of the participants developed meningoencephalitis. The cause of the meningoencephalitis in the patients that received the vaccine has not been definitively determined; however, analysis of two case reports from the AN-1792 vaccine trial suggest that the meningoencephalitis may have been caused by a T cell-mediated autoimmune response, whereas production of anti-Aβ Abs may have been therapeutic to the AD patients. Therefore, to reduce the risk of an adverse T cell-mediated immune response to Aβ immunotherapy we have designed a prototype epitope vaccine that contains the immunodominant B cell epitope of Aβ in tandem with the synthetic universal Th cell pan HLA DR epitope, pan HLA DR-btading peptide (PADRE). Importantly, the PADRE-Aβ1-15 sequence lacks the T cell epitope of Aβ. Immunization of BALB/c mice with the PADRE-Aβ1-15 epitope vaccine produced high titers of anti-Aβ Abs. Splenocytes from immunized mice showed robust T cell stimulation in response to peptides containing PADRE. However, splenocytes from immunized mice were not reactivated by the Aβ peptide. New preclinical trials in amyloid precursor protein transgenic mouse models may help to develop novel immunogen-adjuvant configurations with the potential to avoid the adverse events that occurred in the first clinical trial.
AB - Immunization of amyloid precursor protein transgenic mice with fibrillar β-amyloid (Aβ) prevents Alzheimer's disease (AD)-like neuropathology. The first immunotherapy clinical trial used fibrillar Aβ, containing the B and T cell self epitopes of Aβ, as the immunogen formulated with QS21 as the adjuvant in the vaccine. Unfortunately, the clinical trial was halted during the phase II stage when 6% of the participants developed meningoencephalitis. The cause of the meningoencephalitis in the patients that received the vaccine has not been definitively determined; however, analysis of two case reports from the AN-1792 vaccine trial suggest that the meningoencephalitis may have been caused by a T cell-mediated autoimmune response, whereas production of anti-Aβ Abs may have been therapeutic to the AD patients. Therefore, to reduce the risk of an adverse T cell-mediated immune response to Aβ immunotherapy we have designed a prototype epitope vaccine that contains the immunodominant B cell epitope of Aβ in tandem with the synthetic universal Th cell pan HLA DR epitope, pan HLA DR-btading peptide (PADRE). Importantly, the PADRE-Aβ1-15 sequence lacks the T cell epitope of Aβ. Immunization of BALB/c mice with the PADRE-Aβ1-15 epitope vaccine produced high titers of anti-Aβ Abs. Splenocytes from immunized mice showed robust T cell stimulation in response to peptides containing PADRE. However, splenocytes from immunized mice were not reactivated by the Aβ peptide. New preclinical trials in amyloid precursor protein transgenic mouse models may help to develop novel immunogen-adjuvant configurations with the potential to avoid the adverse events that occurred in the first clinical trial.
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U2 - 10.4049/jimmunol.174.3.1580
DO - 10.4049/jimmunol.174.3.1580
M3 - Article
C2 - 15661919
AN - SCOPUS:12444268257
SN - 0022-1767
VL - 174
SP - 1580
EP - 1586
JO - Journal of Immunology
JF - Journal of Immunology
IS - 3
ER -