COMPARISON OF 2 TECHNIQUES (FLOW-CYTOMETRY AND ALKALINE IMMUNOPHOSPHATASE) IN THE EVALUATION OF ALVEOLAR MACROPHAGE IMMUNOPHENOTYPE

The alveolar macrophage (AM) plays an essential role in the pathogenes is of interstitial lung diseases. The expression of specific membrane antigens is related to the functional or madurative status of the cell s of mononuclear phagocyte system. The aim of this study was to analyz e the expression of several markers (HLA-DR, CD11b, CD16, CD14) in AM obtained by bronchoalveolar lavage from control patients (n = 6), pati ents with sarcoidosis (n = 6), diffuse neoplastic infiltration of the lung (n = 7), pulmonary fibrosis (n = 4), and hypersensitivity pneumon itis (n = 3) by two evaluation techniques (flow cytometry and alkaline immunophosphatase). In the light of the results we can conclude that in the immunophenotypical study of the alveolar macrophage, flow cytom etry (with semiquantitative evaluation to avoid the problem of autoflu orescence) is a useful tool in the evaluation of those antigens that a re only weakly or moderately expressed on AM (CD11b or CD14), whereas the alkaline immunophosphatase technique is of great interest in the e valuation of those that are strongly expressed (i.e., HLA DR). Additio nally, the variable expression of the different antigens in the differ ent alveolar-interstitial pathological states is patent in some diseas es.