Access the full article and editorial published in the European Respiratory Journal
The study included 101 women with LAM and 22 healthy controls from the National Centre for LAM in the UK. A second cohort of 152 women from the USA was used for replication and for a survival study. Researchers carried out genotyping studies (which identify differences in the DNA sequence) with all participants, and mass spectrometry proteomics with 50 LAM patients and 20 controls.
The study surveyed proteins from serum samples and 126 proteins were detected in all patients in the initial discovery cohort. Proteomic analysis showed VTDB was 2.6-fold lower in LAM than controls, and that VTDB was also lower in women with progressive LAM compared with stable LAM.
Genotyping studies suggested that genotype is not responsible for the lower VTDB levels in LAM versus controls.
The data also showed an association between VTDB genotype and median time of death or transplant.
The researchers say this suggests that VTDB is a novel biomarker of disease severity and clinical outcome in LAM, and that the GC genotype is the first genetic host factor found to influence transplant-free survival in LAM.
The findings are discussed in more detail in an accompanying editorial by Heng-Jia Liu and Elizabeth Henske, also published in the ERJ.