The asthmatic inflammatory responses present different type of cells involved in this process, such as: Lymphocytes and Eosinophils. In experienced hands the bronchoalveolar lavage (BAL) is a well-tolerated and valuable tool for investigation of basic mechanisms in asthma and other immunological respiratory diseases. The purpose of this work was to study the different cells involved in asthmatic inflammatory responses in allergic and aspirin sensitivity patients and compared with Extrinsic Allergic Alveolitis patients (EAA) by BAL procedure. We studied 27 asthmatic patients. This group was divided by etiological conditions in: allergic asthmatic patients (a) (n: 19), (9 male and 10 female) demonstrated by reversible fall of FEV 1 (3) 20% and 2 or more positive skin test for common aeroallergens. The aspirin asthmatic patients (b) (n: 8) (5 male and 3 female) demonstrated by progressive challenge with aspirin and fall of FEV 1 (3) 20%. The third group with compatible symptoms and signs of EAA, demonstrated by lung biopsy, (n: 9) (8 male and 1 female) (c). We determined in all patients: Total IgE serum level by ELISA test. BAL was performed by standard procedure in all patients. The cells count were performed in BAL and were separated in Eosinophils, T lymphocytes defined by monoclonal anti CD 3 antibody, Lymphocytes CD 4 and CD 8 by monoclonal anti CD 4 and CD 8 antibodies respectively. The B lymphocytes defined by surface immunoglobulin isotypes IgG, IgM, IgA and IgE. The IgE level was in (a) 630 +/- 350 kU/L, in (b) it was 85 +/- 62 kU/L and in EAA (c) 55 +/- 23 kU/L, p < .0005. Eosinophil percentage in (a) was 25 +/- 13% of cells, in (b) was 28 +/- 15% of cells, NS, and 0 in (c), p < .0005. Lymphocytes T level was 43 +/- 15% of cells in (a), it was 32 +/- 15% of cells in (b) and it was 54 +/- 19% of cells in (c), NS. Lymphocytes CD 4 (+) level was 30 +/- 10% of cells in (a), it was 24 +/- 11% of cells in (b) and it was 8 +/- 6% of cells in (c), p < .005. Lymphocytes CD8 level was 8 +/- 6% of cells in (a), it was 7 +/- 4% of cells in (b) and it was 44 +/- 15% of cells in EAA (c), p < .005. Lymphocytes B level was 8 +/- 4% cells in (a), it was 2.9 +/- 2.5% cells in (b) and it was 3 +/- 2.7% of cells in (c), p < .025. The features described here suggest the importance of the Eosinophils and CD 4 +/- Lymphocytes in asthmatic response of allergic asthmatic patients as well as in aspirin sensitivity asthmatic patients. The LBA cellular profile of E.AA patients presented eosinophilia and CE8+ Lymphocite predominance when compared with both asthmatic cellular profile.