APOPTOSIS AND BCL-2 EXPRESSION OF DUST-LADEN MACROPHAGES OF HUMAN BRONCHOPULMONARY LYMPH NODES / 解剖学报

ABSTRACT

Objective To investigate apoptosis and bcl-2 expression of dust cells in human bronchopulmonary lymph nodes and murine peritoneal macrophages treated with carbon particles and study the relation of apoptosis of dust-laden macrophages and structural changes of the lymph nodes. Methods Distribution of dust particles, apoptotic cells and structural changes of the lymph nodes were viewed on paraffin sections and ultrathin sections. Apoptosis and bcl-2 expression of dust cells in human bronchopulmonary lymph nodes and macrophages treated with carbon particles were observed with TUNEL staining and bcl-2 antibody labeling. Results In the bronchopulmonary lymph nodes of the adult group, dust particles were deposited significantly in macrophages, the lymphatic tissue decreased, collagen fibres and density of blood vessels increased. In ultrathin section, the nucleus condensed and contained vacuoles. There were TUNEL-positive cells and bcl-2 labeling positive cells in dust cells of the lymph nodes and macrophages 24*!h after phagocytizing carbon particles. Bcl-2 was expressed strongly in the active macrophages decomposing dust particles or carbon particles. Conclusion Deposition of dust particles induces apoptosis and overexpression of antiapoptotic gene bcl-2 of macrophages in human bronchopulmonary lymph nodes. Structural changes of the bronchopulmonary lymph nodes in adult may relate to apoptosis of dust-laden macrophages.