Predicting Disease Progression in Cystic Fibrosis

Interleukin-17A: A Potential Therapeutic Target in Chronic Lung Diseases

BACKGROUND

Interleukin-17A (IL-17A) is a pro-inflammatory cytokine that has gained a lot of attention because of its involvement in respiratory diseases. Interleukin-17 cytokine family includes six members, out of which, IL-17A participates towards the immune responses in allergy and inflammation. It also modulates the progression of respiratory disorders.

OBJECTIVE

The present review is an insight into the involvement and contributions of the proinflammatory cytokine IL-17A in chronic respiratory diseases like Idiopathic Pulmonary Fibrosis (IPF), Chronic Obstructive Pulmonary Distress (COPD), asthma, pneumonia, obliterative bronchiolitis, lung cancer and many others.

CONCLUSION

IL-17A is a major regulator of inflammatory responses. In all the mentioned diseases, IL- 17A plays a prime role in inducing the diseases, whereas the lack of this pro-inflammatory cytokine reduces the severity of respective respiratory diseases. Thereby, this review suggests IL-17A as an instrumental target in chronic respiratory diseases.

Sputum microbiota is predictive of long-term clinical outcomes in young adults with cystic fibrosis

BACKGROUND

Complex polymicrobial communities infect cystic fibrosis (CF) lower airways. Generally, communities with low diversity, dominated by classical CF pathogens, associate with worsened patient status at sample collection. However, it is not known if the microbiome can predict future outcomes. We sought to determine if the microbiome could be adapted as a biomarker for patient prognostication.

METHODS

We retrospectively assessed prospectively collected sputum from a cohort of 104 individuals aged 18-22 to determine factors associated with progression to early end-stage lung disease (eESLD; death/transplantation <25 years) and rapid pulmonary function decline (>-3%/year FEV₁ over the ensuing 5 years). Illumina MiSeq paired-end sequencing of the V3-V4 region of the 16S rRNA was used to define the airway microbiome.

RESULTS

Based on the primary outcome analysed, 17 individuals (16%) subsequently progressed to eESLD. They were more likely to have sputum with low alpha diversity, dominated by specific pathogens including Pseudomonas. Communities with abundant Streptococcus were observed to be protective. Microbial communities clustered together by baseline lung disease stage and subsequent progression to eESLD. Multivariable analysis identified baseline lung function and alpha diversity as independent predictors of eESLD. For the secondary outcomes, 58 and 47 patients were classified as rapid progressors based on absolute and relative definitions of lung function decline, respectively. Patients with low alpha diversity were similarly more likely to be classified as experiencing rapid lung function decline over the ensuing 5 years when adjusted for baseline lung function.

CONCLUSIONS

We observed that the diversity of microbial communities in CF airways is predictive of progression to eESLD and disproportionate lung function decline and may therefore represent a novel biomarker.