Objective To observe the antibody responses induced by recombinant plasmid pIRES- fimA:IL15 via nasal immunization to BABL/c mice and the regulation of IL- 15 to sIgA. Methods BABL/c mice were immunized with recombinant plasmids pIRES- fimA:IL15 and pIRES- fimA via nasal or intramuscular route. Serum IgG and salivary sIgA levels after immunization were analyzed by ELISA. Results Nasal immunization with plasmids pIRESfimA: IL15 or pIRES- fimA elicited significant higher level of salivary FimA- specific sIgA responses compared with intramuscular immunization. There was no significant difference of the serum IgG responses between nasal immunization mice and intramuscular immunization mice. Nasal immunization with plasmid pIRES - fimA:IL15 elicited significant higher level of salivary sIgA response than with pIRES- fimA（P
