The aim of this study was to enhance specific mucosal, systemic, and cell-mediated immunity and to induce earlier onset of protection against direct-contact challenge in @entity291 by intranasal delivery of a nanoparticle-based nasal vaccine against @entity4021 ( @entity4021 ). In this study, two kinds of nanoparticle-based nasal vaccines against type A @entity4021 were designed: (1) chitosan-coated @entity7050 ( @entity7050 ) loaded with plasmid DNA (Chi- @entity7050 -DNA) and (2) chitosan- @entity7970 and inactivated @entity4021 virus (FMDV) (Chi-Tre-Inactivated). @entity291 were immunized by an intranasal route with nanoparticles and then challenged for 48 hours by direct contact with two infected donor @entity291 per pen. Donors were inoculated intradermally in the tongue 48 hours before challenge, with 0.2 mL @entity291 -passaged FMDV. Serological and mucosal antibody responses were evaluated, and @entity778 were quantified. FMDV-specific secretory immunoglobulin (Ig)A (sIgA) antibodies in nasal washes were initially detected at 4 days postvaccination (dpv) with two kinds of nanoparticles. The highest levels of sIgA expression were observed in nasal washes, at 10 dpv, from animals with Chi- @entity7050 -DNA nanoparticles, followed by animals immunized once by intranasal route with a double dose of Chi-Tre-Inactivated nanoparticles and animals immunized by intranasal route three times with Chi-Tre-Inactivated nanoparticles (P<0.05). FMDV-specific IgA antibodies in serum showed a similar pattern. All animals immunized by intranasal route developed low levels of detectable IgG in serum at 10 dpv. Following stimulation with FMDV, the highest levels of proliferation were observed in splenocytes harvested from Chi- @entity7050 -DNA-immunized animals, followed by proliferation of cells harvested from Chi-Tre-Inactivated nanoparticle-immunized animals (P<0.05). Higher protection rates were associated with the highest sIgA antibody responses induced in the Chi- @entity7050 -DNA nanoparticle-immunized group. Only one animal was clinically affected with mild signs after 7 days of contact challenge, after a delay of 2-3 days compared with the clinically affected negative-control group. Of the five animals directly challenged that were vaccinated by intranasal route with a double dose of Chi-Tre-Inactivated, four were clinically infected; however, the degree of severity of disease in this group was lower than in control @entity291 . The number of viral RNA copies in nasal swabs from the vaccinated, severely infected group was significantly higher than in swabs from the vaccinated, clinically protected group. These data suggested that intranasal delivery of Chi- @entity7050 -DNA nanoparticles resulted in higher levels of mucosal, systemic, and cell-mediated immunity than did of Chi-Tre-Inactivated nanoparticles. In conclusion, although intranasal delivery with FMDV antigen mediated by nanoparticles did not provide complete clinical protection, it reduced disease severity and @entity778 and delayed clinical symptoms. Chi- @entity7050 -DNA nanoparticle vaccines have potential as a nasal delivery system for vaccines.

Induction of mucosal immune responses and protection of @entity291 against direct-contact challenge by intranasal delivery with XXXX virus antigen mediated by nanoparticles.

@entity7970 :: ('MESH:D014199', 'Chemical') :: ['trehalose'] @entity778 :: ('MESH:D015658', 'Disease') :: ['virus excretion', 'virus excretion and the number of contact infections'] @entity4021 :: ('MESH:D005536', 'Disease') :: ['foot-and-mouth disease', 'type A foot-and-mouth disease', 'FMD'] @entity7050 :: ('MESH:C043435', 'Chemical') :: ['PLGA', 'poly(lactic-co-glycolic acid)'] @entity291 :: ('9913', 'Species') :: ['cattle', 'Cattle']
@entity4021 :: (MESH:D005536,Disease) :: ['foot-and-mouth disease']
