The relationship between differential cell counts and latex-stimulated luminol and lucigenin-amplified chemiluminescence (CL) was investigated by mixing alveolar macrophages (AM) obtained at bronchoalveolar lavage (BAL) with allogeneic peripheral blood neutrophils (PMN) in varying proportions. In 5 non-asthmatic subjects, the mean luminol-amplified CL increased linearly from 2.1 (0.9 SEM) x 10(5) counts per second (cps) with less than 2% PMN, greater than 96% AM to 47.3 (11.1 SEM) x 10(5) cps with greater than 94% PMN, 0% AM (r = 0.996, p less than 0.001). The regression had a y-intercept indistinguishable from 0 cps, suggesting that luminol-amplified CL exclusively reflected PMN activity. Using the same technique, the mean lucigenin-amplified CL showed a fall from 35 (2.3 SEM) x 10(5) cps with a cell population of greater than 96% AM, less than 2% PMN to 20 (2.3 SEM) x 10(5) cps with 0% AM, greater than 94% PMN. Both PMN and AM appeared to contribute to lucigenin-amplified CL, with AM contributing approximately 1.7 times as much activity per cell as PMN. Lucigenin-amplified CL appeared to be an appropriate technique for measuring AM activity when the proportion of PMN in mixed cell populations was small. A linear relationship was found between percent PMN count and luminol-amplified CL measured in a mixed BAL cell population from asthmatic subjects (p less than 0.01) and non-asthmatic controls (p less than 0.01). The slope of this regression line was significantly greater for subjects with asthma than for control subjects (p less than 0.01), suggesting a uniform increase in PMN activity in cells obtained from asthmatic airways.