NK cell activity was examined in 40 patients with radiographically defined asbstosis and 54 sex- and age- matched controls in oder to investigate immunological abnormality in asbestosis.
The results were as follows:
1. NK cell activity in healthy controls was 17.4±12.2%. NK cell activity was independent of the donor's sex and age.
2. NK cell activity in asbestosis (32.3±18.2%) was significantly higher (p<0.001) than that in healthy controls.
3. NK cell activity showed a tendency to decrease as asbestosis progressed.
4. NK cell activity in patients exposed to asbestos dust for over 21 years was significantly higher (p<0.01) than in patients exposed for less than 20 years.
5. NK cell activity in patients with pleural thickening was significantly higher (p<0.05) than in patients without pleural thickening.
6. NK cell activity in patients with asbestosis-related lung cancer was significantly lower (p<0.05) than that in patients without lung cancer.
7. An increase in IgG was seen in 35%, in IgA in 30%, in IgM in 10% and in IgE 16%. ANA was detected in one of 11 cases, and rheumatoid factor was detected in 6 out of 11 cases.
The above results suggest that NK cell activity might be an useful immunological parameter in evaluating the development of asbestosis and asbestosis-related lung cancer.
