Smytheman Thomas, Pecor Tiffany, Miller Dana E, Ferede Debora, Kaur Suhavi, Harband Matthew H, Abdelaal Hazem F M, Guerrero-Bustamante Carlos A, Freeman Krista G, Harrington Whitney E, Frenkel Lisa M, Hatfull Graham F, Coler Rhea N, Larsen Sasha E
Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA.
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
Virol J. 2025 Jan 20;22(1):14. doi: 10.1186/s12985-024-02552-2.
For much of the last decade, tuberculosis (TB) was the leading cause of mortality due to an infectious pathogen (Mycobacterium tuberculosis, M.tb). Approximately 1.3 million deaths in 2023 worldwide were attributed to TB disease. Focused intervention strategies to block transmission would significantly reduce the global health burden of TB. Mycobacteriophages (phages) are a sorely underutilized biologic therapy for the pathogen M.tb, and here we aimed to address outstanding questions about their utility for clinical applications. We aimed to determine the impact of repeated mucosal or intravenous (IV) delivery of representative anti-M.tb phage FionnbharthΔ45Δ47 (Fionnbharth) in a preclinical mouse model. In addition, we specifically sought to understand which route induced anti-phage antibodies, which may reduce the long-term impact of phage therapy. C57BL/6 mice were dosed weekly for 6 weeks by either route and serum and bronchoalveolar lavage fluid (BALf) were evaluated for anti-phage humoral responses by ELISA. We found that aerosol delivery disperses phage across all lung lobes where M.tb is also found after experimental infection by the same route. Repeated aerosol delivery was well tolerated and did not induce robust neutralizing humoral immunity. In contrast, Mice receiving IV phage developed increasing magnitude and neutralizing total IgG and IgA responses over time. To determine whether pre-treatment environmental exposure to Fionnbharth-like phages could induce antibody responses that are potentially neutralizing, ~ 500 human plasma samples from normal donors were evaluated by ELISA. We observed that 5% of samples had antibodies to Fionnbharth (with end point titers > 10 dilution), although none were neutralizing. Furthermore, we found that highly-purified phage preparations did not activate mouse or human derived toll like receptor (TLR) 4 or TLR9 in HEKblue reporter assays. These data together support using Fionnbharth in anti-M.tb therapy phage cocktail strategies and that aerosol delivery should be prioritized for further efficacy testing.
在过去十年的大部分时间里，结核病（TB）是由传染性病原体（结核分枝杆菌，M.tb）导致死亡的主要原因。2023年全球约有130万人死于结核病。旨在阻断传播的针对性干预策略将显著减轻全球结核病的健康负担。分枝杆菌噬菌体（噬菌体）是一种尚未得到充分利用的针对病原体M.tb的生物疗法，在此我们旨在解决有关其临床应用效用的悬而未决的问题。我们旨在确定在临床前小鼠模型中重复经黏膜或静脉内（IV）递送代表性抗M.tb噬菌体FionnbharthΔ45Δ47（Fionnbharth）的影响。此外，我们特别试图了解哪种途径会诱导抗噬菌体抗体，这可能会降低噬菌体疗法的长期影响。通过这两种途径每周给C57BL/6小鼠给药，持续6周，并通过ELISA评估血清和支气管肺泡灌洗液（BALf）中的抗噬菌体体液反应。我们发现气溶胶递送可将噬菌体分散到所有肺叶，在通过相同途径进行实验性感染后，M.tb也存在于这些肺叶中。重复气溶胶递送耐受性良好，且未诱导强大的中和性体液免疫。相比之下，接受静脉内噬菌体的小鼠随着时间的推移产生的中和性总IgG和IgA反应的幅度不断增加。为了确定预先接触类似Fionnbharth的噬菌体的环境是否会诱导可能具有中和作用的抗体反应，通过ELISA对来自正常供体的约500份人类血浆样本进行了评估。我们观察到5%的样本具有针对Fionnbharth的抗体（终点效价>10倍稀释），尽管没有一种具有中和作用。此外，我们发现在HEKblue报告基因检测中，高度纯化的噬菌体制剂不会激活小鼠或人类来源的Toll样受体（TLR）4或TLR9。这些数据共同支持在抗M.tb治疗噬菌体鸡尾酒策略中使用Fionnbharth，并且应优先考虑气溶胶递送以进行进一步的疗效测试。
