The Department of Genetic Medicine at Weill Cornell leads a dynamic and innovative translational research program, advancing diverse fields such as Genetic Therapy and Personalized Medicine.
Our translational research program aims to leverage our expertise in genetic therapies and personalized medicine to develop clinical solutions that target the molecular causes of human diseases.
The Department of Genetic Medicine advances treatments and diagnostics through diverse clinical trials, including drug testing and research to better understand diseases.
The Department of Genetic Medicine at Weill Cornell leads a dynamic and innovative translational research program, advancing diverse fields such as Genetic Therapy and Personalized Medicine.
Our translational research program aims to leverage our expertise in genetic therapies and personalized medicine to develop clinical solutions that target the molecular causes of human diseases.
The Department of Genetic Medicine advances treatments and diagnostics through diverse clinical trials, including drug testing and research to better understand diseases.
Kazeros A, Harvey B, Carolan B, Vanni H, Krause A, Crystal R
Journal
Am J Respir Cell Mol Biol
Volume
39
Issue
6
Pagination
747-57
Date Published
06/27/2008
ISSN
1535-4989
Keywords
Apoptosis, Macrophages, Alveolar, Smoking
Abstract
Mononuclear phagocytes play an important role in the removal of apoptotic cells by expressing cell surface receptors that recognize and remove apoptotic cells. Based on the knowledge that cigarette smoking is associated with increased lung cell turnover, we hypothesized that alveolar macrophages (AMs) of normal cigarette smokers may exhibit enhanced expression of apoptotic cell removal receptor genes. AMs obtained by bronchoalveolar lavage of normal nonsmokers (n = 11) and phenotypic normal smokers (n = 13; 36 +/- 6 pack-years) were screened for mRNA expression of all known apoptotic cell removal receptors using Affymetrix HG-U133 Plus 2.0 microarray chips with TaqMan RT-PCR confirmation. Of the 14 known apoptotic receptors expressed, only MER tyrosine kinase (MERTK), a transmembrane tyrosine kinase receptor, was significantly up-regulated in smokers. MERTK expression was then assessed in AMs of smokers versus nonsmokers by TaqMan RT-PCR, immunocytochemistry, Western analysis, and flow analysis. Smoker AMs had up-regulation of MERTK mRNA levels (smoker vs. nonsmoker: 3.6-fold by microarray, P < 0.003; 9.5-fold by TaqMan RT-PCR, P < 0.02). Immunocytochemistry demonstrated a qualitative increase in MERTK protein expression on AMs of smokers. Increased protein expression of MERTK on AMs of smokers was confirmed by Western and flow analyses (P < 0.007 and P < 0.0002, respectively). MERTK, a cell surface receptor that recognizes apoptotic cells, is expressed on human AMs, and its expression is up-regulated in AMs of cigarette smokers. This up-regulation of MERTK may reflect an increased demand for removal of apoptotic cells in smokers, an observation with implications for the development of chronic obstructive pulmonary disease, a disorder associated with dysregulated apoptosis of lung parenchymal cells.