RESUMO
In this study, Mtb8.4 and HspX, which are expressed at proliferating and dormant stages of Mycobacterium tuberculosis (M. tuberculosis), respectively, were chosen to construct two fusion proteins, Mtb8.4-HspX (8.4H) and HspX-Mtb8.4 (H8.4), and we investigated whether the antigen dose and protein sequential order could impact the immunogenicity and protective efficacy of these fusion protein vaccines against M. tuberculosis. C57BL/6 mice were vaccinated with new constructions containing a fusion protein with adjuvant of N, N'-dimethyl-N, N'-dioctadecylammonium bromide (DDA) or a mixed adjuvant composed of DDA, polyribocytidylic acid and gelatin (DPG), and the antigen specific immune responses and protective efficacy against M. tuberculosis H37Rv were evaluated. The results showed that both antigens, Mtb8.4-HspX and HspX-Mtb8.4, could elicit strong human T cell responses. With the existing of DDA adjuvant, HspX-Mtb8.4 induced significantly higher secretion level of IFN-γ and TNF-α in spleen cells than Mtb8.4-HspX (p<0.05). In its protective efficacy study, the isolated bacterial Colony Form Unit (CFU) in H8.4-DPG group was significantly reduced compared to 8.4H-DPG group (p<0.05). Furthermore, with the stimulation of Mtb8.4 in vitro, the secretion of IFN-γ and TNF-α from mice immunized with 20µg of H8.4 exhibited relative higher level than the group immunized by 7µg of H8.4 (p<0.05), whereas, IL-2 secreting showed contrary result. The data suggest that the antigen sequential order and dose selection should be considered when a tuberculosis protein vaccine is to be constructed and its immune strategy is to be planned.
Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Leucócitos Mononucleares/imunologia , Mycobacterium tuberculosis/fisiologia , Vacinas contra a Tuberculose/genética , Tuberculose/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Células Cultivadas , Feminino , Imunização , Interferon gama/metabolismo , Leucócitos Mononucleares/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Compostos de Amônio Quaternário/administração & dosagem , Vacinas contra a Tuberculose/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Vacinas de Subunidades AntigênicasRESUMO
To better control tuberculosis (TB) epidemics in developing countries a real need exists to study the liquefaction and cavity formation that occur in pulmonary TB lesions. This report is the first to evaluate the effects of immunomodulators on these two processes in a rabbit skin model. The effects of recombinant human interferon-γ (rIFN-γ), recombinant human interleukin-2 (rIL-2), dexamethasone and cyclophosphamide (CTX) were evaluated in TB lesions produced by intradermal injection of 5 × 10(6) viable BCG bacilli. Recombinant IL-2 and rIFN-γ accelerated the liquefaction and healing of the lesions, and reduced the bacterial load. In contrast, dexamethasone inhibited the liquefaction of the lesions, and increased the bacterial load. The effect of CTX was similar to dexamethasone but not as pronounced. Serum levels of IL-2 were higher during the liquefaction and healing phases in the rIL-2 and rIFN-γ groups. Therefore, immunomodulators affect both the development of TB lesions and the survival of the mycobacteria within them. This study suggests that the rabbit skin model can be a valuable method to select therapeutic agents that could inhibit liquefaction and cavity formation in pulmonary tuberculosis.
Assuntos
Antituberculosos/uso terapêutico , Fatores Imunológicos/uso terapêutico , Úlcera Cutânea/tratamento farmacológico , Tuberculose Cutânea/tratamento farmacológico , Animais , Carga Bacteriana , Ciclofosfamida/uso terapêutico , Citocinas/sangue , Dexametasona/uso terapêutico , Modelos Animais de Doenças , Edema/tratamento farmacológico , Edema/microbiologia , Interferon gama/uso terapêutico , Interleucina-2/sangue , Interleucina-2/uso terapêutico , Mycobacterium bovis/isolamento & purificação , Coelhos , Proteínas Recombinantes/uso terapêutico , Úlcera Cutânea/microbiologia , Úlcera Cutânea/patologia , Tuberculose Cutânea/microbiologiaRESUMO
Starting with a high-throughput screening lead, a novel series of CCR5 antagonists was developed utilizing an information-based approach. Improvement of pharmacokinetic properties for the series was pursued by SAR exploration of the lead template. The synthesis, SAR and biological profiles of the series are described.
Assuntos
Fármacos Anti-HIV/química , Benzamidas/química , Antagonistas dos Receptores CCR5 , Inibidores da Fusão de HIV/química , Pirróis/química , Animais , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacocinética , Benzamidas/síntese química , Benzamidas/farmacologia , Inibidores da Fusão de HIV/síntese química , Inibidores da Fusão de HIV/farmacocinética , Humanos , Microssomos Hepáticos/metabolismo , Pirróis/síntese química , Pirróis/farmacocinética , Ratos , Receptores CCR5/metabolismo , Relação Estrutura-AtividadeRESUMO
Replacement of the cyclic carbamate in our previously disclosed 1-oxa-3,9-diazaspiro[5.5]undecan-2-one template led to the discovery of two novel series of 3,9-diazaspiro[5.5]undecane and undeca-2-one CCR5 antagonists. The synthesis, SAR, and antiviral activities of these two series are described. One compound (32) was found to have attractive combination of antiviral potency, selectivity, and pharmacokinetic profile. The asymmetric synthesis of 32 was also accomplished and both enantiomers were equally potent.
