Home
|
Inbox
|
Search
|
View Abstract
Validating Immunoproteasome Activity Profiling In Peripheral Blood Of Healthy Smokers And Copd Patients As A Biomarker Approachg Immunoproteasome Activity Profiling In Peripheral Blood Of Healthy Smokers And Copd Patients As A Biomarker Approach
Description
.abstract img { width:300px !important; height:auto; display:block; text-align:center; margin-top:10px } .abstract { overflow-x:scroll } .abstract table { width:100%; display:block; border:hidden; border-collapse: collapse; margin-top:10px } .abstract td, th { border-top: 1px solid #ddd; padding: 4px 8px; } .abstract tbody tr:nth-child(even) td { background-color: #efefef; } .abstract a { overflow-wrap: break-word; word-wrap: break-word; }
A3121 - Validating Immunoproteasome Activity Profiling In Peripheral Blood Of Healthy Smokers And Copd Patients As A Biomarker Approachg Immunoproteasome Activity Profiling In Peripheral Blood Of Healthy Smokers And Copd Patients As A Biomarker Approach
Author Block: S. Meiners1, I. E. Kammerl1, A. Schneider1, J. Schimmer1, M. Frankenberger1, A. Koch2; 1CPC, Munich, Germany, 2University Hospital, Ludwigs-Maximilians University Munich, Munich, Germany.
Rationale:
The immunoproteasome is the main proteolytic machinery in immune cells and play an essential role in effective antiviral defense by improving generation of major histocompatibility class I antigen epitopes. We recently showed that immunoproteasome activity is markedly reduced in end-stage COPD lung tissue and expression is impaired in early-stage bronchoalveolar lavage cells (Kammerl et al. AJRCCM 2016 Jun 1;193(11):1230-41). We hypothesize that altered immunoproteasome function will affect the immune response in COPD patients and contributes to disease progression and virus-induced exacerbations. The aim of this study is to characterize immunoproteasome function in peripheral blood of COPD patients in order to evaluate immunoproteasome activity as a potential biomarker for COPD disease status and severity.
Methods and Results:
For a first proof-of-concept analysis of proteasome activity profiling in blood, we characterized proteasome function inpPeripheral blood mononuclear cells (PBMCs) of 20 male non-smokers and 20 healthy smokers (18-30y, smokers with at least 1.5 pack years). We then assayed proteasome function in 20 COPD patients (GOLD III-IV) and 20 healthy age-matched controls. Serum cotinine levels confirmed the smoking status of the probands. Immune cell composition was resolved by FACS analysis. Proteasome and immunoproteasome subunit expression were determined by RTqPCR, Western blot or proteome analysis. Proteasome and immunoproteasome activity was analyzed using subunit-specific activity based probes and native gel analysis. In smokers, we did not observe any change in mRNA levels. However, mass spectrometry revealed that several of the 20S and 19S proteasome subunits were elevated. While proteasome activity measured by activity-based probes was not significantly altered, assembly of active proteasome complexes was slightly changed. In PBMCs of COPD patients, expression of the immunoproteasome subunits LMP2, LMP7 and MECL1 was increased. Activity of the proteasome was not significantly changed but showed a trend towards increased immunoproteasome function.
Conclusion:
Our preliminary results indicate that proteasome activity profiling in the blood is feasible. While the proteasome system in the blood of young healthy smokers is rather stable, COPD patients show significant changes in RNA expression of the immunoproteasome. We are currently validating these findings in additional COPD patients and controls and will then correlate immunoproteasome function with the patients’ data to validate immunoproteasome activity profiling as a potential biomarker approach for COPD.
Author Block: S. Meiners1, I. E. Kammerl1, A. Schneider1, J. Schimmer1, M. Frankenberger1, A. Koch2; 1CPC, Munich, Germany, 2University Hospital, Ludwigs-Maximilians University Munich, Munich, Germany.
Rationale:
The immunoproteasome is the main proteolytic machinery in immune cells and play an essential role in effective antiviral defense by improving generation of major histocompatibility class I antigen epitopes. We recently showed that immunoproteasome activity is markedly reduced in end-stage COPD lung tissue and expression is impaired in early-stage bronchoalveolar lavage cells (Kammerl et al. AJRCCM 2016 Jun 1;193(11):1230-41). We hypothesize that altered immunoproteasome function will affect the immune response in COPD patients and contributes to disease progression and virus-induced exacerbations. The aim of this study is to characterize immunoproteasome function in peripheral blood of COPD patients in order to evaluate immunoproteasome activity as a potential biomarker for COPD disease status and severity.
Methods and Results:
For a first proof-of-concept analysis of proteasome activity profiling in blood, we characterized proteasome function inpPeripheral blood mononuclear cells (PBMCs) of 20 male non-smokers and 20 healthy smokers (18-30y, smokers with at least 1.5 pack years). We then assayed proteasome function in 20 COPD patients (GOLD III-IV) and 20 healthy age-matched controls. Serum cotinine levels confirmed the smoking status of the probands. Immune cell composition was resolved by FACS analysis. Proteasome and immunoproteasome subunit expression were determined by RTqPCR, Western blot or proteome analysis. Proteasome and immunoproteasome activity was analyzed using subunit-specific activity based probes and native gel analysis. In smokers, we did not observe any change in mRNA levels. However, mass spectrometry revealed that several of the 20S and 19S proteasome subunits were elevated. While proteasome activity measured by activity-based probes was not significantly altered, assembly of active proteasome complexes was slightly changed. In PBMCs of COPD patients, expression of the immunoproteasome subunits LMP2, LMP7 and MECL1 was increased. Activity of the proteasome was not significantly changed but showed a trend towards increased immunoproteasome function.
Conclusion:
Our preliminary results indicate that proteasome activity profiling in the blood is feasible. While the proteasome system in the blood of young healthy smokers is rather stable, COPD patients show significant changes in RNA expression of the immunoproteasome. We are currently validating these findings in additional COPD patients and controls and will then correlate immunoproteasome function with the patients’ data to validate immunoproteasome activity profiling as a potential biomarker approach for COPD.
|
Home
|
Inbox
|
Search
|