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Updated: Apr 17, 2026
Author Spotlight: Investigating the Key Factors of Obliterative Bronchiolitis After Lung Transplantation
Published on: November 10, 2023
Metalloproteinase Profiling in Lung Transplant Recipients With Good Outcome and Bronchiolitis Obliterans Syndrome
Irene H Heijink1, Dennie Rozeveld, Sicco van der Heide
11 Department of Pathology and Medical Biology, Experimental Pulmonology and Inflammation Research, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands. 2 Department of Pulmonology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands. 3 GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands. 4 Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands. 5 Department of Analytical Biochemistry, Center for Pharmacy, University of Groningen, the Netherlands.
Background:
Bronchiolitis obliterans syndrome (BOS), the major cause of death on lung transplantation, is characterized by bronchiolar inflammation and tissue remodeling. Matrix metalloproteinases (MMPs) have been implicated in these processes, although it is still unclear whether MMP activity and binding to their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs), is abnormal in BOS.
Methods:
We studied total MMP-1,-2,-3,-7,-8,-9,-12,-13 levels, their activity state using activity-based extraction and their binding to TIMP-1, -2, -3, and -4 in bronchoalveolar lavage (BAL) of lung transplant recipients with good outcome and BOS using a multiplex immunoassay.
Results:
The BAL levels of TIMP-1 and -2 and MMP-2, -3, -7, -8, and -9 were significantly increased in BOS compared to good outcome recipients. Interestingly, activity of MMP-7, but none of the other MMPs, was detected in good outcome recipients, whereas no active MMPs were observed in BOS recipients. However, BAL levels of TIMP-bound MMP-8 and -9 were higher in BOS than in good outcome recipients, suggesting activity of these MMPs in an earlier stage.
Conclusions:
We demonstrate that development of BOS is associated with increased levels of TIMP-1 and -2 and total MMP-2, -3, -7, -8, and -9. Although active MMP-7 was only observed in good outcome recipients, levels of TIMP-bound MMP-8 and -9 were higher in BOS. By enabling profiling of active and TIMP-bound MMPs, our novel method may open opportunities for the screening of early predictors for BOS.
