Effects of Muscarinic Acetylcholine 3 Receptor^208-227 Peptide Immunization on Autoimmune Response in Nonobese Diabetic Mice

Figure 1

Immunization with the M3R^208–227 peptide induced peptide-specific antibodies. NOD/LtJ mice received 100 μg M3R^208–227 (rhombus) or CP (square) diluted in PBS and emulsified in incomplete Freund’s adjuvant. PBS immunizations (triangle) were used as an additional control. Sera were obtained from the mice in each group every seven days after the second immunization, and these samples were diluted 1 : 50. Antibody titer determination was performed by ELISA. The results showed that peptide-specific antibodies were successfully induced in NOD/LtJ mice immunized with the M3R^208–227 peptide (a), but no changes were observed in antibody titers against M3R^228–237 (C-terminal) (b) and M3R^514–527 (the third extracellular loop) (c) in M3R^208–227 peptide immunized NOD/LtJ mice (mean ± SD; ^∗𝑃<0.05; ^∗∗𝑃<0.005).

(a)

(b)

(c)