Department of Pulmonary Medicine, Unit 1462, The University of Texas MD Anderson Cancer Center, Houston, TX USA.
Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX USA.
Front Pharmacol. 2014 Feb 6;5:8. doi: 10.3389/fphar.2014.00008. eCollection 2014.
We have previously discovered a synergistically therapeutic combination of two Toll-like receptor ligands, an oligodeoxynucleotide (ODN) and Pam2CSK4. Aerosolization of these ligands stimulates innate immunity within the lungs to prevent pneumonia from bacterial and viral pathogens. Here we examined the safety and tolerability of this treatment in mice, and characterized the expression of biomarkers of innate immune activation. We found that neutrophils appeared in lung lavage fluid 4 h after treatment, reached a peak at 48 h, and resolved by 7 days. The peak of neutrophil influx was accompanied by a small increase in lung permeability. Despite the abundance of neutrophils in lung lavage fluid, only rare neutrophils were visible histopathologically in the interstitium surrounding bronchi and veins and none were visible in alveolar airspaces. The cytokines interleukin 6 (IL-6), tumour necrosis factor, and Chemokine (C-X-C motif) ligand 2 rose several hundred-fold in lung lavage fluid 4 h after treatment in a dose-dependent and synergistic manner, providing useful biomarkers of lung activation. IL-6 rose fivefold in serum with delayed kinetics compared to its rise in lavage fluid, and might serve as a systemic biomarker of immune activation of the lungs. The dose-response relationship of lavage fluid cytokines was preserved in mice that underwent myeloablative treatment with cytosine arabinoside to model the treatment of hematologic malignancy. There were no overt signs of distress in mice treated with ODN/Pam2CSK4 in doses up to eightfold the therapeutic dose, and no changes in temperature, respiratory rate, or behavioral signs of sickness including sugar water preference, food disappearance, cage exploration or social interaction, though there was a small degree of transient weight loss. We conclude that treatment with aerosolized ODN/Pam2CSK4 is well tolerated in mice, and that innate immune activation of the lungs can be monitored by the measurement of inflammatory cytokines in lung lavage fluid and serum.
我们之前发现了两种 Toll 样受体配体（一种寡脱氧核苷酸（ODN）和 Pam2CSK4）的协同治疗组合。这些配体的雾化吸入可刺激肺部的固有免疫，以防止细菌和病毒病原体引起的肺炎。在这里，我们检查了这种治疗方法在小鼠中的安全性和耐受性，并对固有免疫激活的生物标志物的表达进行了特征描述。我们发现，治疗后 4 小时，中性粒细胞出现在肺灌洗液中，48 小时达到峰值，7 天内恢复。中性粒细胞流入的峰值伴随着肺通透性的轻微增加。尽管肺灌洗液中中性粒细胞丰富，但在支气管和静脉周围的间质中仅可见少量组织病理学可见的中性粒细胞，在肺泡气腔中则不可见。细胞因子白细胞介素 6（IL-6）、肿瘤坏死因子和趋化因子（C-X-C 基序）配体 2 在治疗后 4 小时以剂量依赖性和协同方式在肺灌洗液中升高数百倍，为肺激活提供了有用的生物标志物。与灌洗液相比，IL-6 在血清中的升高具有延迟的动力学，并且可能作为肺部免疫激活的系统生物标志物。在接受阿糖胞苷进行骨髓清除性治疗以模拟血液恶性肿瘤治疗的小鼠中，灌洗液细胞因子的剂量反应关系得以保留。用 ODN/Pam2CSK4 治疗的小鼠没有明显的不适迹象，剂量高达治疗剂量的 8 倍，并且没有体温、呼吸率或疾病行为迹象（包括糖水偏好、食物消失、笼内探索或社交互动）变化，尽管有一定程度的短暂体重减轻。我们得出结论，用雾化 ODN/Pam2CSK4 治疗在小鼠中耐受性良好，并且可以通过测量肺灌洗液和血清中的炎症细胞因子来监测肺部的固有免疫激活。
