The effect of angiotensin II on the accessory function of BALF macrophages in the cases of sarcoidosis of long duration
Nagai, S.
Nihon Kyobu Shikkan Gakkai Zasshi 26(9): 957-964
1988
ISSN/ISBN: 0301-1542 PMID: 3266769 Document Number: 323070
Most cases of sarcoidosis show spontaneous regression but there are some cases with a long duration. Therefore, there must be some factors which result in a state of continuous activation of macrophages to maintain T lymphocyte alveolitis. It has been reported that ACE is released from activated macrophages at the lesions. We hypothesized that this enzyme could convert Angiotension I to Angiotensin II, which could enhance the accessory function of BALF macrophages in T cell proliferation. From this viewpoint, we investigated the effect of A-I/A-II, which was added exogenously, on the accessory function. The study population included 7 cases of active prolonged sarcoidosis, 7 freshly active cases and 8 healthy controls. In mixed cell culture of blood T cells and BALF macrophages under stimulation of anti-OKT3 antibody for 72 hrs, 3H-thymidine incorporation in the last 18 hrs was counted. Angiotensin I/Angiotensin II was added from the start of culture. We found that A-II enhanced this accessory function in the cases of sarcoidosis with longer duration, but not in the cases of freshly active sarcoidosis and healthy controls. These findings suggest that T lymphocyte alveolitis is maintained in the cases of sarcoidosis with longer duration by an autostimulatory mechanism whereby A-II is derived from activated macrophages.