Objective: To prepare the holoantigens of morphine and morphine-6-succinyl, and to evaluate the efficacy of both of the haptens in eliciting immune responses and their effects on morphine withdrawal symptoms in male mice.
Methods: Morphine-6-succinyl was prepared using acid anhydride mixture, and conjugated, along with morphine, with Blue carrier in the presence of carbodi imide. Immunization of mice with both the holoantigens and Freund adjuvant was performed, followed by determination of the antibody titer in the mouse serum with competitive ELISA and morphine dependence evaluation.
Results: The titers of the antibodies exceeded 1:8 000 in the serum of mice immunized with both holoantigens, and morphine- 6-succinyl induced a higher titer that was maintained for a longer period. The inhibition rates of the antisera to morphine and morphine-6-auccinyl had both reached 50%, and increased in a dose-dependent manner.
Conclusion: Both morphine carrier conjugates can elicit high-titer antibody response in mice and relieve morphine addiction.