Pulmonary disorders triggered by inhalation of occupational and environment
al mineral particulates can be endpoints of a chronic inflammatory process
in which alveolar macrophages (AMs), as a first line of defense, play a cru
cial role, The biological processes involved in particulate-induced activat
ion of AMs include indirect or direct interactions of particulates with the
cell membrane, subsequent stimulation of signal transduction pathways, and
activation of gene transcription. Depending on the nature of particulate i
nvolved, particulate-induced activation of AMs has been shown to result in
the release of potent mediators, such as reactive oxygen and nitrogen speci
es, cytokines, eicosanoids, and growth factors. The prolonged and enhanced
production of such effector molecules may result in a complex cascade of ev
ents that can contribute to the development of pulmonary disorders. This pa
per will give a short review of the present knowledge of AM interaction wit
h inhaled mineral particulates and of the possible implications these inter
actions may have in the development of pulmonary disorders.