Effect of Haemophilus influenzae infection on lung CD8+ T cells in COPD

描述(由申请人提供)： 慢性阻塞性肺疾病(COPD)是美国第三大死亡原因，但目前还没有治疗方法来阻止这种疾病的发展。COPD的特点是气流阻塞，不同程度的气道重塑和肺泡破坏，以及包括中性粒细胞、巨噬细胞和CD8+T细胞在内的肺炎性细胞的涌入。FEV1测定的CD8+T细胞数量与肺功能呈负相关，提示CD8+T细胞参与了COPD的发病。CD8+T细胞可以释放炎性细胞因子和介质，这可能会导致肺破坏。当肺CD8+T细胞与Toll样受体识别的合成细菌配体，特别是TLR2/1共同刺激时，这些效应功能被增强。TLR2/1识别非分型流感嗜血杆菌(NTHI)的外膜蛋白，NTHI是COPD中与呼吸道感染相关的主要细菌病原体之一，既是稳定期疾病，也是导致病情恶化的重要感染触发因素。本研究的目的是确定肺CD8+T细胞是否会通过上调其效应器功能，如分泌炎性细胞因子、杀伤自体肺细胞和招募额外的CD8+T细胞来对NTHI共刺激做出反应。为了实现这一目标，将使用经同意接受临床指征手术切除的受试者的肺组织。组织将从患有和不患有COPD的两名受试者身上获得。分离的肺CD8+T细胞将与抗原提呈细胞和NTHI共同培养，以确定NTHI共同刺激对效应分子产生的影响，这将通过流式细胞仪进行测量。这将与肺功能的测量相关联。共培养试验也将用于确定NTHI共刺激是否诱导肺CD8+T细胞杀伤自体肺细胞。通过直接从人肺组织中分离CD8+T细胞，并在体外用它们研究CD8和NTHI的相互作用，我们可能会对COPD的发病机制和进展有独特的见解。

DESCRIPTION (provided by applicant): Chronic obstructive pulmonary disease (COPD) is the 3rd leading cause of death in the U.S., yet there are no current therapeutic treatments to halt the progression of this disease. COPD is characterized by airflow obstruction, variable degrees of airway remodeling and alveolar destruction, and an influx of lung inflammatory cells, including neutrophils, macrophages, and CD8+ T cells. The inverse correlation between numbers of airway CD8+ T cells and lung function, as determined by FEV1, implicates CD8+ T cells in COPD pathogenesis. CD8+ T cells can release inflammatory cytokines and mediators that could contribute to lung destruction. These effectors functions are augmented when lung CD8+ T cells are co-stimulated with synthetic bacterial ligands recognized by toll-like receptors (TLRs), in particular TLR2/1. TLR2/1 is known to recognize the outer membrane protein of nontypeable Haemophilus influenzae (NTHI), one of the predominant bacterial pathogens associated with airway infection in COPD, both in stable disease and as an important infectious trigger of exacerbations. The goal of this study is to determine whether lung CD8+ T cells will respond to NTHI co-stimulation by up-regulating their effector functions, such as secreting inflammatory cytokines, killing autologous lung cells, and recruiting additional CD8+ T cells. To carry out this objective, lung tissue from consented subjects undergoing clinically-indicated surgical resections will be used. Tissue will be obtained from both subjects with and without COPD. Isolated lung CD8+ T cells will be co-cultured with antigen- presenting cells and NTHI to determine what effect NTHI co-stimulation has on the production of effector molecules, which will be measured by flow cytometry. This will be correlated with measures of lung function. The co-culture assay will also be used to determine whether NTHI co-stimulation induces the lung CD8+ T cells to kill autologous lung cells. By isolating CD8+ T cells directly from human lung tissue and using them in vitro to study CD8 and NTHI interactions, we may gain unique insights into how COPD pathogenesis is initiated and progresses.