High CD95 expression of BAL lymphocytes predicts chronic course in patients with sarcoidosis

The prognosis of sarcoidosis is highly variable, with spontaneous remission in some patients. Apoptosis may be associated with spontaneous resolution of the granulomata. CD95 (Fas), an apoptotic molecule, and CD29 and CD45RO (T-cell memory markers) are expressed at higher levels on T lymphocytes from sarcoid patients compared with normal subjects. However, the prognostic significance of CD95, CD29 and CD45RO expression in sarcoidosis is not clear. It was hypothesized that expression of CD95 would correlate with spontaneous remission.

CD29, CD45, CD45RO and CD95 expression of BAL fluid and peripheral blood (PB) lymphocytes was studied with flow cytometry in 50 patients with sarcoidosis. Results of the 15 chronic patients and 21 patients who remitted spontaneously were compared.

BAL CD95 (59 vs 8, P = 0.002), and PB CD95 (48 vs 18, P = 0.004) and PB CD45RO (50 vs 41, P = 0.003) expression was significantly higher in patients with chronic disease compared with those with spontaneous remission. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy for these markers were: BAL CD95 (cut-off: 42.5%) 73.3%, 85.7%, 78.6%, 81.8% and 80.6%; PB CD95 (cut-off: 25%) 86.7%, 66.7%, 65%, 87.5% and 75%; and PB CD45RO (cut-off: 44.5%) 80%, 61.9%, 60%, 81.3% and 69.4%, respectively.

Levels of BAL and PB CD95 and PB CD45RO were unexpectedly elevated in patients with chronic disease and may be useful in predicting prognosis in patients with sarcoidosis. Further studies with more patients are necessary to confirm the prognostic role and cut-off value for these markers.