Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, Jeju National University, Jeju 63243, Republic of Korea.
Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, Jeju National University, Jeju 63243, Republic of Korea.
Immunobiology. 2023 Sep;228(5):152709. doi: 10.1016/j.imbio.2023.152709. Epub 2023 Jul 17.
Adjuvants are used to elicit strong immune responses for vaccines that show poor immunogenicity. Previously, we demonstrated that a sonicated bacterin of Bordetella bronchiseptica can be used as a safe adjuvant that enhances the antigen-presenting capability of dendritic cells (DCs). In this study, we purified the lipopolysaccharide (LPS) of B. bronchiseptica (Bb-LPS) and investigated its immunogenic effects on DCs compared to those of Escherichia coli O26:B6 (O26)-derived LPS (O26-LPS), a positive control. Bb-LPS was purified using an LPS extraction kit. Limulus amebocyte lysate assay was performed to determine the optimal concentration of Bb-LPS and O26-LPS for treatment. Bb-LPS increased the metabolic activity of DCs at a concentration of 0 to 250 EU/mL, similar to that of O26-LPS. Bb-LPS significantly increased the expression level of CD40 and CD54, related to the immune responses of DCs. Bb-LPS enhanced the antigen-presenting capability of DCs and significantly increased the interferon-gamma/interleukin-4 ratio of CD4 T cells co-cultured with DCs to 0.95 (p < 0.05). Moreover, Bb-LPS increased the production of pro-inflammatory cytokines in a safer manner than that obtained by O26-LPS. In vivo safety tests revealed that Bb-LPS was less toxic than O26-LPS in mice. This study demonstrated that Bb-LPS showed unique immune characteristics and immunogenic effects on the antigen-presenting capability of DCs, which differed from those of O26-LPS. This study provides valuable information for basic and clinical research for developing safe vaccine adjuvants.
佐剂用于增强免疫原性差的疫苗产生强烈的免疫应答。此前，我们证明博德特氏菌巴氏杆菌的超声细菌疫苗可以作为一种安全的佐剂，增强树突状细胞（DCs）的抗原呈递能力。在这项研究中，我们纯化了博德特氏菌（Bb）的脂多糖（LPS），并研究了其与阳性对照大肠杆菌 O26:B6（O26）衍生的 LPS（O26-LPS）相比对 DCs 的免疫原性作用。Bb-LPS 是使用 LPS 提取试剂盒进行纯化的。使用鲎变形细胞溶解物测定法确定 Bb-LPS 和 O26-LPS 的最佳处理浓度。Bb-LPS 在 0 至 250 EU/mL 浓度范围内增加了 DCs 的代谢活性，与 O26-LPS 相似。Bb-LPS 显著增加了与 DCs 免疫反应相关的 CD40 和 CD54 的表达水平。Bb-LPS 增强了 DCs 的抗原呈递能力，并使与 DCs 共培养的 CD4 T 细胞的干扰素-γ/白细胞介素-4 比值显著增加到 0.95（p<0.05）。此外，Bb-LPS 以比 O26-LPS 更安全的方式增加了促炎细胞因子的产生。体内安全性测试表明，与 O26-LPS 相比，Bb-LPS 在小鼠中毒性更低。这项研究表明，与 O26-LPS 相比，Bb-LPS 对 DCs 的抗原呈递能力具有独特的免疫特性和免疫原性作用。本研究为开发安全疫苗佐剂的基础和临床研究提供了有价值的信息。
