Chronic obstructive pulmonary disease (COPD) is a chronic lung disease that is considered to be both preventable and treatable. It is highly associated with smoking and those who are frequently exposed to smoking environments.
Symptoms of COPD usually include cough and shortness of breath, and the disease is characterized by sputum production, neutrophilic bronchial airway inflammation, bacterial colonization, and very poor health conditions. It is expected that by 2030 COPD will be the fourth leading cause of death according to the World Health Organization (WHO) (after heart disease, cardiovascular disease and HIV / AIDS).
Dachang Wu, Chenxia Hou, Yanxia Li, Zinan Zhao, Jianjun Liu, Xin Lu, Xueqi Shang and Yi Xin, the study authors, aimed to determine the composition of the COPD patients’ sputum in terms of the microbiota environment. They wanted to analyze the microorganisms during the clinical stable phase of their diseases.
To accomplish this researchers used a molecular genetics-based approach. Through DNA isolation, PCR amplification and DGGE profiling, they performed several tests to understand the pathogenic organisms that were part of the sputum composition of both COPD patients and healthy groups (to compare them). PCR-denaturing gradient gel electrophoresis (DGGE) and universal primers aiming at the V3 region of the gene ’16S rRNA’ and excised bands cloned for sequencing were successfully managed as well.
To quantify each subpopulation of microbiota, real-time PCR was used; they targeted specific sequences of Streptococcus pneumoniae, Klebsiella pneumoniae and Pseudomonas aeruginosa to measure their presence.
The DGGE profiles showed relevant differences between COPD patients’ sputum and healthy patients’ sputum, and the real-time PCR displayed a higher amount of Streptococcus pneumonia, Klebsiella pneumonia and Pseudomonas aeruginosa in the composition of the COPD patients’ sputum.
Results suggest a very strong relationship between the differences of the microbiota and the disease itself and, by determining the exact microorganisms flora, it might be possible to improve diagnosis and treatment techniques to ease these patients’ lives.