New pathway opens CF treatment possibilities
inflammation in lung tissue, a discovery that could help in the
design of more targeted drug treatments for patients with various
lung diseases, including cystic fibrosis, reports Wai Lang
Chu.
The pathway heralds a new direction in which laboratory researchers into lung inflammation can take especially as current research remains stumped at how the inflammation - a characteristic of CF, is never "switched off," thus infections cannot be completely treated.
Researchers from the Laboratory of Lung Immunology and Host Defence at the Children's Hospital of Pittsburgh, measured mediators of inflammation in cystic fibrosis patients, focusing on interleukin 23 (IL-23) and interleukin-17 (IL-17).
In previous studies, IL-23 and IL-17 have been found to be good targets for neutralisation and blocking the inflammatory response. In identifying these mediators of inflammation it may be possible to treat the patient earlier and more effectively, preventing lung disease or give patients a better quality of life.
Jay Kolls, who is the division chief of Pediatric Pulmonology at the hospital said: "What's intriguing is that by targeting IL-17 we may also be able to inhibit IL-8, a well-known inflammatory instigator in CF, since our laboratory studies suggest expression of this cytokine is dependant on IL-17."
"A treatment that focuses on IL-17 instead of IL-8 may be the more rational approach," he added.
The discovery of this new pathway identifies a target for more specific regulation of the inflammatory pathways that ultimately contribute to lung damage in CF. Modulating this pathway could lead to a safer and more effective anti-inflammatory therapy for CF and perhaps other inflammatory lung diseases.
"Clinical trials of non-specific anti-inflammatory therapies have shown some clinical benefit, but significant side effects have limited their utility," said co-author Joseph Pilewski, associate professor of Medicine, Pediatrics and Cell Biology and Physiology at the University of Pittsburgh School of Medicine.
More than 30,000 patients in the US have CF, and Pennsylvania is one of only 11 states that screen for lung disease. Throughout most of the world, lung infections are a major cause of death and illness among children. Although death rates are low in the United States, lung infection is the leading reason children visit doctors.
Dr Kolls' team is investigating gene-based strategies to probe the immune system's ability to fight infection in the T-cell depleted setting.
In mice when T-cells are depleted, the mice are able to protect themselves against infections when given an experimental therapy that takes certain proteins secreted by T-cells - the growth factor, IL-17, for example - and reconstitutes them into the system.
Such an approach might someday treat infections, which do not respond well to antibiotics, such as pneumocystis.
Dr Kolls said, "I think that if we can understand the inflammation processes, we can make an impact on their lives." He added that the discovery could also have applications with Multiple Sclerosis, as well as Inflammatory Bowel Disease.
The results of this study are to be published in the July issue of The Journal of Immunology.
