Exposure to
asbestos results in serious risk of developing lung and mesothelial diseases. Currently, there are no
biomarkers that can be used to diagnose
asbestos exposure. The purpose of the present study was to determine whether the levels or detection rate of
chemokine (C-C motif) ligand 3 (CCL3) in the serum are elevated in persons exposed to
asbestos. The primary study group consisted of 76 healthy subjects not exposed to
asbestos and 172 healthy subjects possibly exposed to
asbestos. The secondary study group consisted of 535 subjects possibly exposed to
asbestos and diagnosed with pleural plaque (412), benign
hydrothorax (10),
asbestosis (86),
lung cancer (17), and
malignant mesothelioma (10). All study subjects who were possibly exposed to
asbestos had a certificate of
asbestos exposure issued by the Japanese Ministry of Health, Labour and Welfare. For the primary study group, levels of serum CCL3 did not differ between the two groups. However, the detection rate of CCL3 in the serum of healthy subjects possibly exposed to
asbestos (30.2%) was significantly higher (P < 0.001) than for the control group (6.6%). The pleural plaque, benign
hydrothorax,
asbestosis, and
lung cancer groups had serum CCL3 levels and detection rates similar to that of healthy subjects possibly exposed to
asbestos. The
CCL3 chemokine was detected in the serum of 9 of the 10 patients diagnosed with
malignant mesothelioma. Three of the patients with
malignant mesothelioma had exceptionally high CCL3 levels.
Malignant mesothelioma cells from four biopsy cases and an autopsy case were positive for CCL3, possibly identifying the source of the CCL3 in the three
malignant mesothelioma patients with exceptionally high serum CCL3 levels. In conclusion, a significantly higher percentage of healthy persons possibly exposed to
asbestos had detectable levels of serum CCL3 compared to healthy unexposed control subjects.