The researchers then correlated the genetic test results with results from microscopic pathology examinations, tissue cultures, X-rays, CT scans, and breathing tests in each patient. They identified six genes that correlate with lymphocytic bronchitis, potentially opening the way to a genetic test that would identify OB before it manifests. "The beauty of this approach is that it could be applied in a regular laboratory," Caughey says.
However, he cautions, "we need to validate this data in a larger, separate set of patients to prove that these biomarker genes actually work. And we're testing that now." Currently, Caughey's research team is studying biopsy samples from more than 100 UCSF lung transplant patients, who regularly undergo biopsies as part of standard follow-up care.
Another potential benefit of the research, predicts Caughey, will be a better understanding of lung rejection at the genetic level. In turn, he believes, this could lead to the development of medications that directly target genes responsible for the scarring process in the lung, instead of anti-rejection drugs that broadly compromise the immune system, which are the major tools currently available to fight lung rejection.
Co-authors of the study were Xiang Xu, MD, PhD, Jeffrey A. Golden, MD, Gregory Dolganov, PhD, Kirk D. Jones, MD, Samantha Donnelly, PhD, and Timothy Weaver, Bsc, all of UCSF.