Immunization regime, antibody responses, and suppression of cocaine-evoked hyperactivity in mice. (A) CocKFE8 nanofibers induced adjuvant-free antibody responses in mice as measured by ELISA and mice with absorbance values higher than the control (PBS-treated) group mean plus three times the standard deviation (i.e., >0.05 absorbance, represented by the dashed line) were defined as CocKFE8 responders (*p < 0.05 vs controls, ^p < 0.05 vs CocKFE8 nonresponders). (B) Vaccination with CocKFE8 did not alter spontaneous locomotor activity (p > 0.05). (D) Mice responding to CocKFE8 nanofiber vaccines show blunted cocaine-evoked locomotor activity (*p < 0.05 vs control). The time course of peripheral activity is divided into 15 min time bins across the 60 min session for both spontaneous and cocaine-evoked locomotor activity. The mean total spontaneous and cocaine-evoked peripheral activity (counts/60 min) (±SEM) is represented in panels (C) and (E), respectively.