| Autor: |
Rana Abadalkareem, Laurie C.K. Lau, Andrew F. Walls, John Pedersen, Rhys George, Rose-Marie Mackay, Yaroslav Shkanov |
| Rok vydání: |
2016 |
| Předmět: |
|
| Zdroj: |
5.3 Allergy and Immunology. |
| DOI: |
10.1183/13993003.congress-2016.oa4957 |
| Popis: |
SP-D, a key orchestrator of innate immunity in the lung, has been found to be degraded in the airways of asthmatic patients. Chronic mast cell activation is also a prominent feature in asthmatic airways, and is associated with the release of mediators of inflammation including a series of proteases. Among these is the lysosomal cysteine-type peptidase DPPI. We have investigated the capacity of DPPI to cleave SP-D and alter its functionality. Recombinant human mast cell protease DPPI was incubated with recombinant fragment human surfactant protein D over a range of physiological conditions and time periods. The potential for SP-D cleavage was analysed by SDS polyacrylamide gel electrophoresis (PAGE), and Western blotting with antibodies specific for SP-D and DPPI was employed to confirm the identity of component proteins. Confirmatory studies were performed investigating native SP-D in bronchoalveolar lavage fluid. Functionality of SP-D was assessed by measuring inhibition of bacterial growth. DPPI induced a concentration-dependent degradation of SP-D with the appearance of new fragments of 8 and 10 kDa. The addition of selective protease inhibitors or heat-inactivation of DPPI resulted in substantially less degradation of SP-D, indicating dependence of an intact catalytic site. The ability of DPPI to alter the structural integrity of SP-D could contribute in important ways to inflammatory changes in the asthmatic lung. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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