Immune rejection of human dystrophin following intramuscular injections ofnaked DNA in mdx mice

Intramuscular administration of plasmid expressing full-length human dystro phin in dystrophin-deficient adult mdx mice resulted in humoral and weak sp ecific T cell responses against the human dystrophin protein. Following pla smid injection, human dystrophin was detected in the injected muscles at 7 days, but decreased thereafter Anti-dystrophin antibodies were found 21 day s following plasmid injection, which coincided with transient myositis. Thi s immune rejection prevented the mice from expressing human dystrophin afte r a second plasmid injection. No anti-DNA antibodies were found. Anti-dystr ophin antibodies were seen in a smaller proportion of plasmid-injected dyst rophin-competent C57BL/10 mice, suggesting that the immune rejection of dys trophin may be explained partially by species differences in the dystrophin protein.