Data from: Loss of GD1-positive Lactobacillus correlates with inflammation in human lungs with COPD

Objectives: The present study assesses the relationship between contents of GD1 (glycerol dehydratase)-positive Lactobacillus, presence of Lactobacillus and the inflammatory response measured in host lung tissue in mild to moderate chronic obstructive pulmonary disease (COPD). We hypothesise that there will be a loss of GD1 producing Lactobacillus with increasing severity of COPD and that GD1 has anti-inflammatory properties. Setting: Secondary care, 1 participating centre in Vancouver, British Columbia, Canada. Participants: 74 individuals who donated non-cancerous portions of their lungs or lobes removed as treatment for lung cancer (normal lung function controls (n=28), persons with mild (GOLD 1) (n=21) and moderate (GOLD 2) COPD (n=25)). Outcome measures: Primary outcome measure was GD1 positivity within each group and whether or not this impacted quantitative histological measures of lung inflammation. Secondary outcome measures included Lactobacillus presence and quantification, and quantitative histological measurements of inflammation and remodelling in early COPD. Results: Total bacterial count (p>0.05) and prevalence of Lactobacillus (p>0.05) did not differ between groups. However, the GD1 gene was detected more frequently in the controls (14%) than in either mild (5%) or moderate (0%) COPD (p<0.05) samples. Macrophage and neutrophil volume fractions (0.012±0.005 (mean±SD) vs 0.026±0.017 and 0.005±0.002 vs 0.015±0.014, respectively) in peripheral lung tissue were reduced in samples positive for the GD1 gene (p<0.0035). Conclusions: A reduction in GD1 positivity is associated with an increased tissue immune inflammatory response in early stage COPD. There is potential for Lactobacillus to be used as a possible therapeutic, however, validation of these results need to be completed before an anti-inflammatory role of Lactobacillus in COPD can be confirmed.

研究目的：本研究旨在评估甘油脱水酶 (glycerol dehydratase, GD1) 阳性乳酸杆菌 (Lactobacillus) 的含量、乳酸杆菌的存在情况与轻中度慢性阻塞性肺疾病 (chronic obstructive pulmonary disease, COPD) 患者宿主肺组织中检测到的炎症反应之间的关联。本研究提出如下假说：随着COPD病情严重程度升高，产GD1的乳酸杆菌丰度会下降，且GD1具有抗炎特性。
研究场景：二级医疗照护，加拿大不列颠哥伦比亚省温哥华市1家参与中心。
研究对象：74名因肺癌接受手术切除并捐赠非癌性肺组织或肺叶的受试者，其中包括肺功能正常的对照组（n=28）、轻度（GOLD 1，n=21）及中度（GOLD 2，n=25）COPD患者。
结局指标：主要结局指标为各组中GD1阳性率，以及GD1阳性是否对肺炎症的定量组织学检测结果存在影响。次要结局指标包括乳酸杆菌的存在情况与定量检测结果，以及早期COPD患者肺组织炎症与重塑的定量组织学检测结果。
研究结果：各组的总细菌计数（p>0.05）及乳酸杆菌检出率（p>0.05）均无显著差异。但对照组GD1基因检出率（14%）显著高于轻度COPD组（5%）与中度COPD组（0%）（p<0.05）。在GD1基因阳性的肺组织样本中，外周肺组织的巨噬细胞和中性粒细胞体积分数分别为0.012±0.005（平均值±标准差）与0.005±0.002，显著低于GD1阴性样本的0.026±0.017与0.015±0.014（p<0.0035）。
研究结论：早期COPD患者中，GD1阳性率降低与肺组织免疫炎症反应增强存在关联。乳酸杆菌具备开发为治疗制剂的潜力，但需先验证本研究结果，方能确认乳酸杆菌在COPD中的抗炎作用。