サルコイドーシスの肺肉芽腫形成に対するPropionibacterium acnesの関与に関する研究

第1編 サルコイドーシス肺胞リンパ球のPropionibacterium acnesに対するInterleukin-2産生及びInterleukin-2受容体発現について

抄録

We previously reported that alveolar lymphocytes in patients with active sarcoidosis are sensitized to Propionibacterium acnes (P. acnes) which may play a significant role in the induction of alveolitis in these patients. We further investigated the production of Interleukin-2 (IL-2), and the responsiveness to IL-2 of alveolar lymphocytes obtained from sarcoidosis patients and stimulated by P. acnes in vitro.
In 21 untreated sarcoidosis patients, 7 treated patients and 13 control subjects, the mean IL-2 activity of fluid released from cultured alveolar lymphocytes was 9.8±15.7 (M±SD), 1.9±4.7 and 0.2±0.8u/ml respectively. The IL-2 activity of lymphocytes from untreated patients was significantly higher than that of control subjects (p<0.02).
Neither peripheral lymphocytes in sarcoidosis patients nor in controls produced IL-2 stimulated by P. acnes.
The responsiveness of alveolar lymphocytes to recombinant IL-2 was evaluated by ³H-thymidine uptake in the presence and absence of P. acnes. Lymphocytes stimulated by P. acnes showed a significantly increased uptake (3, 766±3, 929 dpm) compared to unstimulated lymphocytes (1, 123±968 dpm) obtained from 11 untreated sarcoidosis patients (p<0.02). On the other hand, the responsiveness of lymphocytes obtained from 6 control subjects was low regardless of stimulation by P. acnes.
There was a significant correlation (p<0.05) between the P. acnes-induced production of IL-2 by alveolar lymphocytes and the blastogenesis of alveolar lymphocytes in untreated sarcoidosis patients.
Our findings indicate that P. acnes stimulates IL-2 production and IL-2 receptor induction in alveolar lymphocytes from patients with active sarcoidosis. This study supported our hypothesis that P. acnes could be an antigen causing sarcoidosis.