A new study under the lead of DZL scientists has shown, autoimmune reactions may be a causal factor in more patients as currently expected. The results have been published in the ‘American Journal of Respiratory and Critical Care Medicine’.
The term interstitial lung disease (ILD) encompasses a diverse range of disorders that are associated with scarring (fibrosis) of the lung tissue. Idiopathic pulmonary fibrosis (IPF) is one of them. This disease leads to the formation of excess fibrous connective tissue in the lung, thereby reducing its elasticity. It also impairs oxygen absorption and overall results in a deterioration of lung function.
“The underlying molecular mechanisms of the individual disease subtypes are not sufficiently understood and are therefore the subject of our research,” explains the first author of the study DZL scientist Dr. Herbert Schiller (see photo, source: HMGU). Since 2015 he has led the DZL junior research group “Systems Medicine of Chronic Lung Disease” at the Institute of Lung Biology at the Helmholtz Zentrum München (DZL site CPC Munich).
In total, the scientists examined lung tissue with the aid of mass spectrometry* obtained from 45 patients with different forms of ILD and compared them with the samples from ten healthy control subjects. In addition, they examined tissue samples of diseased and healthy areas of skin from six patients with fibrotic skin diseases.
“Interestingly, both in the lungs and skin of the fibrosis patients, we were able to identify an increased abundance of proteins specific for antibody-producing plasma cells,” explains lead author Schiller. Observations under the microscope supported these findings. This suggests that in many patients the disease could be caused by an autoimmune disorder that attacks so far unknown proteins in the lung. At present, however, there is no evidence of a causal relationship, and further studies are already initiated.
“In our study we found a high prevalence of antibody-forming plasma cells in scarred lung tissue, and the number of these cells was correlated with the reduction in the patients’ lung function,” Schiller notes. On the basis of these observations, he surmises that autoimmunity may play a bigger part in idiopathic forms of lung fibrosis than was previously assumed.
“The use of mass spectrometry to identify auto-antibodies and their antigens present in the blood of ILD patients could be the key to better diagnostic classification in the future and to potential immunotherapeutic approaches,” Schiller says. His junior research group is therefore currently engaged in developing new methods of classifying autoantibodies and in examining larger patient cohorts.
Dr. Herbert Schiller
Helmholtz Zentrum München - German Research Center for Environmental Health
Comprehensive Pneumology Center (DZL Site CPC Munich)
Max-Lebsche-Platz 31, D-81377 München
Tel. +49 89 3187 1194, email: herbert.schiller@helmholtz-muenchen.de
* Mass spectrometry is a technique used to analyze molecular masses. The substance to be examined is transferred into the gas phase and ionized. The ions are accelerated using an electric field and passed into a mass analyzer, where they are sorted and separated according to their mass-to-charge ratio.
Schiller, HB et al. (2017): Deep proteome profiling reveals common prevalence of MZB1-positive plasma B cells in human lung and skin fibrosis. American Journal of Respiratory and Critical Care Medicine, DOI: 10.1164/rccm.201611-2263OC
Source: Helmholtz Zentrum München (in English)
The cause of idiopathic pulmonary fibrosis (IPF), in particular, is still entirely unknown. Currently the outlook for IPF (median survival time of 2-5 years following diagnosis) is classified as poor. Only recently two anti-fibrotic drugs – Pirfenidon and Nintedanib – have become available for the treatment of IPF. However, since antifibrotic drugs can only slow down the progression of the disease but not halt it, lung transplantation is currently the only definitive treatment for IPF.
Since October 2015, first author Dr. Herbert Schiller has headed the DZL junior research group “Systems Medicine of Chronic Lung Disease” at the Institute of Lung Research, Helmholtz Zentrum München. The senior author of the study is Prof. Oliver Eickelberg. Until the turn of the year, he was Member of the DZL Board of Directors and Director of the Institute of Lung Biology and Disease (ILBD), Helmholtz Zentrum München. He currently heads the Division of Pulmonary and Critical Care Medicine at the University of Colorado School of Medicine in Denver.
