RESUMO
The mite protein Der p 1 is a major trigger of allergy and atopic asthma world-wide, and thus, a good vaccine candidate for allergy prevention. Since it is a cysteine protease, the catalytic effects of Der p 1 vaccination may be unpredictable. One approach to reduce this risk is to vaccinate with DNA encoding enzymatically inactive forms of Der p 1. Here we show that Der p 1 DNA without its native pre-pro sequences potently induced Der p 1-specific antibodies, as long as its pre-sequence was substituted by another leader sequence. Without any pre-pro sequence, the same DNA fragment was well expressed but failed to induce significant level of anti-Der p 1 antibodies, without further boosting by protein.
Assuntos
Alérgenos/imunologia , Antígenos de Dermatophagoides/imunologia , Imunoglobulina G/biossíntese , Ácaros/imunologia , Vacinas de DNA/imunologia , Alérgenos/biossíntese , Alérgenos/genética , Animais , Antígenos de Dermatophagoides/biossíntese , Antígenos de Dermatophagoides/genética , Proteínas de Artrópodes , Cisteína Endopeptidases , Eletroporação , Feminino , Genes Reporter , Genes Sintéticos , Proteínas de Fluorescência Verde , Imunoglobulina G/imunologia , Injeções Intramusculares , Proteínas Luminescentes/genética , Camundongos , Camundongos Endogâmicos BALB C , Músculo Esquelético/metabolismo , Fragmentos de Peptídeos/genética , Plasmídeos/genética , Plasmídeos/imunologia , Precursores de Proteínas/genética , Precursores de Proteínas/imunologia , Sinais Direcionadores de Proteínas/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/imunologia , Rinite Alérgica Perene/prevenção & controle , Deleção de Sequência , Vacinação , Vacinas de DNA/administração & dosagemRESUMO
Our previous studies indicated that intramuscular (i.m.) immunisation with full length Der p 1 cDNA induced significant humoral response to the left domain (approximately corresponding to amino acids 1-116) but not to the right domain (approximately corresponding to amino acids 117-222) of Der p 1 allergen. This study explored the use of chitosan-DNA nanoparticles for oral immunisation to induce immune responses specific to both the left and right domains of Der p 1. DNA constructs pDer p 1 (1-222) and pDer p 1 (114-222) were complexed with chitosan and delivered orally followed by an i.m. injection of pDer p 1 (1-222) 13 weeks later. Such approach has successfully primed Th1-skewed immune responses against both domains of Der p 1. This strategy could be further optimised for more efficacious gene vaccination for full length Der p 1.