Previous studies have shown that oligodeoxynucleotides containing unmethylated CpG motifs were used as adjuvants for immunoregulation and immune response. This study was to explore the activation effects of Bifidobact...Previous studies have shown that oligodeoxynucleotides containing unmethylated CpG motifs were used as adjuvants for immunoregulation and immune response. This study was to explore the activation effects of Bifidobacteria DNA containing unmethylated CpG motifs (CpG DNA) on murine macrophage J774A.1 cells. The genomic DNA of Bifidobacteria was extracted and purified, and the methylation degree of CpG motifs was tested. The phagocytic ability of the macrophages was detected by flow cytometry. The cytokines (IL-1β, IL-6, IL-12p40 and TNF-α) levels in the culture supernatants of Bifidobacteria DNA treated J774A.1 cells were assayed by ELISA. The content of nitric oxide (NO) was detected by Griess reagent. After treated with Bifidobacteria DNA for 24h, Nile Red stain increased in J774A.1 macrophage, which suggested that the lipid metabolism increased in the macrophages. The phagocytic ability and levels of NO and cytokines of IL-1β, IL-6, IL-12p40 and TNF-α were significantly higher than PBS group and CT DNA group. The results indicated that Bifidobacteria DNA could activate murine macrophages J774A.1, which could provide scientific basis for the research and application of microorganism DNA preparation. Cellular & Molecular Immunology. 2005;2(6):473-478.展开更多
<em>Background:</em> Antisense peptide nucleic acids (PNAs) exhibit growth inhibitory effects on bacteria by inhibiting the expression of essential genes and could be promising therapeutic agents for treat...<em>Background:</em> Antisense peptide nucleic acids (PNAs) exhibit growth inhibitory effects on bacteria by inhibiting the expression of essential genes and could be promising therapeutic agents for treating bacterial infections. A study was carried out to determine the efficacy of several antisense PNAs in inhibiting extracellular and intracellular growth of <em>Mycobacterium smegmatis</em>. <em>Methods: </em>Six PNAs obtained from a commercial supplier were tested to evaluate the inhibitory effect on bacterial growth by inhibiting the expression of the following essential genes: <em>inhA </em>(a fatty acid elongase), <em>rpsL</em> (ribosomal S12 protein), <em>gyrA</em> (DNA gyrase), <em>pncA</em> (pyrazinamidase), <em>polA</em> (DNA polymerase I) and <em>rpoC</em> (RNA polymerase <em>β</em> subunit) of <em>M. smegmatis</em>. Each PNA was tested at 20 μM, 10 μM, 5 μM and 2.5 μM concentrations to determine whether they caused a dose dependent killing of <em>M. smegmatis</em> cultured in Middlebrook 7H9 broth or in a J774A.1 murine macrophage cell line.<em> Results:</em> In Middlebrook broth, the strong growth inhibitory effect against <em>M. smegmatis</em> was observed by PNAs targeting the <em>inhA </em>and <em>rpsL</em> genes at all four concentrations. The PNAs targeting the<em> pncA</em>, <em>polA</em> and<em> rpoC</em> genes were found to exhibit strong growth inhibition against <em>M. smegmatis</em> but only at 20 μM concentration. No growth inhibition of <em>M. smegmatis </em>was seen in pure culture when treated with PNAs targeting gyrA and a mismatch PNA targeting dnaG (DNA primase). All six PNAs showed killing of <em>M. smegmatis </em>in J774A.1 macrophage cell line that were statistically significant (p < 0.05). <em>Conclusion:</em> It may be concluded from this study that PNAs could be potential therapeutics for mycobacterial infections.展开更多
Coumarins belong to a diverse group of naturally occurring non-nutrient phytochemicals known as benzo-α- pyrones. In this study, esculetin, a 6,7-dihydroxy derivative of coumarin with pleiotropic biological activitie...Coumarins belong to a diverse group of naturally occurring non-nutrient phytochemicals known as benzo-α- pyrones. In this study, esculetin, a 6,7-dihydroxy derivative of coumarin with pleiotropic biological activities, was found to have no significant cytotoxic effect on normal murine macrophages, but it could increase the in vivo migration of the thioglycollate-elicited macrophages in a dose-dependent manner. Moreover, esculetin significantly increased the endocytic activity, and augmented the nitric oxide production and iNOS gene expression in LPS-treated macrophages. In addition, in vivo administration of esculetin into mice was shown to increase the mitogenesis of splenic lymphocytes towards Con A and LPS stimulations, and induced the LAK activity of splenic lymphocytes. Collectively, our results indicate that esculetin could exert immunomodulatory effects on murine macrophages and lymphocytes, both in vitro and in vivo, and this might be one of the possible mechanisms by which coumarins can exert their chemopreventive and anti-tumor activities in vivo. Cellular & Molecular Immunology. 2005;2(3): 181-188.展开更多
文摘Previous studies have shown that oligodeoxynucleotides containing unmethylated CpG motifs were used as adjuvants for immunoregulation and immune response. This study was to explore the activation effects of Bifidobacteria DNA containing unmethylated CpG motifs (CpG DNA) on murine macrophage J774A.1 cells. The genomic DNA of Bifidobacteria was extracted and purified, and the methylation degree of CpG motifs was tested. The phagocytic ability of the macrophages was detected by flow cytometry. The cytokines (IL-1β, IL-6, IL-12p40 and TNF-α) levels in the culture supernatants of Bifidobacteria DNA treated J774A.1 cells were assayed by ELISA. The content of nitric oxide (NO) was detected by Griess reagent. After treated with Bifidobacteria DNA for 24h, Nile Red stain increased in J774A.1 macrophage, which suggested that the lipid metabolism increased in the macrophages. The phagocytic ability and levels of NO and cytokines of IL-1β, IL-6, IL-12p40 and TNF-α were significantly higher than PBS group and CT DNA group. The results indicated that Bifidobacteria DNA could activate murine macrophages J774A.1, which could provide scientific basis for the research and application of microorganism DNA preparation. Cellular & Molecular Immunology. 2005;2(6):473-478.
文摘<em>Background:</em> Antisense peptide nucleic acids (PNAs) exhibit growth inhibitory effects on bacteria by inhibiting the expression of essential genes and could be promising therapeutic agents for treating bacterial infections. A study was carried out to determine the efficacy of several antisense PNAs in inhibiting extracellular and intracellular growth of <em>Mycobacterium smegmatis</em>. <em>Methods: </em>Six PNAs obtained from a commercial supplier were tested to evaluate the inhibitory effect on bacterial growth by inhibiting the expression of the following essential genes: <em>inhA </em>(a fatty acid elongase), <em>rpsL</em> (ribosomal S12 protein), <em>gyrA</em> (DNA gyrase), <em>pncA</em> (pyrazinamidase), <em>polA</em> (DNA polymerase I) and <em>rpoC</em> (RNA polymerase <em>β</em> subunit) of <em>M. smegmatis</em>. Each PNA was tested at 20 μM, 10 μM, 5 μM and 2.5 μM concentrations to determine whether they caused a dose dependent killing of <em>M. smegmatis</em> cultured in Middlebrook 7H9 broth or in a J774A.1 murine macrophage cell line.<em> Results:</em> In Middlebrook broth, the strong growth inhibitory effect against <em>M. smegmatis</em> was observed by PNAs targeting the <em>inhA </em>and <em>rpsL</em> genes at all four concentrations. The PNAs targeting the<em> pncA</em>, <em>polA</em> and<em> rpoC</em> genes were found to exhibit strong growth inhibition against <em>M. smegmatis</em> but only at 20 μM concentration. No growth inhibition of <em>M. smegmatis </em>was seen in pure culture when treated with PNAs targeting gyrA and a mismatch PNA targeting dnaG (DNA primase). All six PNAs showed killing of <em>M. smegmatis </em>in J774A.1 macrophage cell line that were statistically significant (p < 0.05). <em>Conclusion:</em> It may be concluded from this study that PNAs could be potential therapeutics for mycobacterial infections.
文摘Coumarins belong to a diverse group of naturally occurring non-nutrient phytochemicals known as benzo-α- pyrones. In this study, esculetin, a 6,7-dihydroxy derivative of coumarin with pleiotropic biological activities, was found to have no significant cytotoxic effect on normal murine macrophages, but it could increase the in vivo migration of the thioglycollate-elicited macrophages in a dose-dependent manner. Moreover, esculetin significantly increased the endocytic activity, and augmented the nitric oxide production and iNOS gene expression in LPS-treated macrophages. In addition, in vivo administration of esculetin into mice was shown to increase the mitogenesis of splenic lymphocytes towards Con A and LPS stimulations, and induced the LAK activity of splenic lymphocytes. Collectively, our results indicate that esculetin could exert immunomodulatory effects on murine macrophages and lymphocytes, both in vitro and in vivo, and this might be one of the possible mechanisms by which coumarins can exert their chemopreventive and anti-tumor activities in vivo. Cellular & Molecular Immunology. 2005;2(3): 181-188.