Lipopolissacarídeos (LPS) de L. interrogans, S. enterica e B. pertussis foram extraídos e as subfrações monofosforil lipídeo A (MPLA) preparadas por hidrólise. O LPS é responsável por forte resposta imunológica e endotóxica em mamíferos, enquanto o MPLA apresenta baixa endotoxicidade e boa capacidade imunomoduladora. Estudamos a atividade adjuvante de LPS e de MPLA em formulações com antígenos LigA ou OmpA contra leptospirose. Testes de imunização e desafio em hamsters confirmaram alta atividade imunoprotetora de LigA e capacidade adjuvante do MPLA de salmonela e de LPS de leptospiras, mas as formulações não foram capazes de bloquear a colonização renal na leptospirose. Os resultados sugerem diferenças na imunidade protetora sistêmica da imunidade protetora renal. / Lipopolysaccharides (LPS) of L. interrogans, S. enterica and B. pertussis were extracted and the subfraction monophosphoril lipid A (MPLA) prepared by hydrolysis. The LPS is responsible for immunological response and endotoxicity in mammallians, while MPLA has reduced endotoxic activity, but maintain the immunomodulatory capacity. We studied the adjuvant capacity of LPS and MPLA in formulations with LigA or OmpA antigens against leptospirosis. Tests of immunization and challenge in hamsters confirmed the high immune protection activity of LigA and adjuvant capacity of MPLA of salmonela and LPS of lepstopiras, however formulations did not block the renal colonization. The results suggest that there are differences in the systemic immune protection from the kidney immune protection.

Lipopolissacarídeos (LPS) de L. interrogans, S. enterica e B. pertussis foram extraídos e as subfrações monofosforil lipídeo A (MPLA) preparadas por hidrólise. O LPS é responsável por forte resposta imunológica e endotóxica em mamíferos, enquanto o MPLA apresenta baixa endotoxicidade e boa capacidade imunomoduladora. Estudamos a atividade adjuvante de LPS e de MPLA em formulações com antígenos LigA ou OmpA contra leptospirose. Testes de imunização e desafio em hamsters confirmaram alta atividade imunoprotetora de LigA e capacidade adjuvante do MPLA de salmonela e de LPS de leptospiras, mas as formulações não foram capazes de bloquear a colonização renal na leptospirose. Os resultados sugerem diferenças na imunidade protetora sistêmica da imunidade protetora renal. / Lipopolysaccharides (LPS) of L. interrogans, S. enterica and B. pertussis were extracted and the subfraction monophosphoril lipid A (MPLA) prepared by hydrolysis. The LPS is responsible for immunological response and endotoxicity in mammallians, while MPLA has reduced endotoxic activity, but maintain the immunomodulatory capacity. We studied the adjuvant capacity of LPS and MPLA in formulations with LigA or OmpA antigens against leptospirosis. Tests of immunization and challenge in hamsters confirmed the high immune protection activity of LigA and adjuvant capacity of MPLA of salmonela and LPS of lepstopiras, however formulations did not block the renal colonization. The results suggest that there are differences in the systemic immune protection from the kidney immune protection.

Total RNA was extracted from chicken oviduct epithelial cells. Avian Beta-defensin (AvBD)-2, -6, and -12 cDNAs were amplified by reverse transcription-PCR and cloned into pRSET A style='msoareast-language:ZH-CN'>, a protein expression vector. The class=SpellE>hexa-histidine-tagged class=SpellE>AvBD peptides were expressed in Escherichia coli (E. coli) BL21(DE3) class=SpellE>plysS and affinity-purified. The antimicrobial activities of the recombinant AvBDs against E. coli style='msoareast-language:ZH-CN;mso-bidiont-style:italic'>, Salmonella class=SpellE>enterica style='mso-bookmark:OLE_LINK9'> serovar Typhimurium (S. class=SpellE>typhimurium), and Staphylococcus aureus style='msoareast-language:ZH-CN'> (S. aureus) were determined. style='msoareast-language:ZH-CN;mso-bidiont-style:italic'> At 8, 16 and 32 µg/ml, all three rAvBDs killed and inhibited the growth style='msoareast-language:ZH-CN'> of E. coli style='msoareast-language:ZH-CN;mso-bidiont-style:italic'>, S. typhimurium, and S. aureus. The killing of rAvBD-2, -6, and -12 against stationary phase E. coli and S. class=SpellE>aureus was pH dependent in the range investigated. style='msoareast-language:ZH-CN'> In addition, the killing-curves showed that rAvBDs exerted their antimicrobial function within 30 minutes of treatment, suggesting the fast killing mechanisms of rAvBDs.