Spontaneous allergic autocytotoxicity (spACT) of white blood cells (WBC) was assessed in six bronchial asthma patients and eighteen normal control individuals. The observed alterations of non-primed WBC membrane were revealed as an increased uptake of trypan blue exclusion dye, an indicator of death cells. The phenomenon of spACT might be associated with a lack of T suppressor cell intervention, increased refractoriness of WBC membrane leading to its increased permeability and enhanced releasability of chemical mediators of anaphylaxis, which probably bypasses IgE events. In six bronchial asthma patients, three were sensitive toward wheat, two had cow milk sensitivity, and one had corn sensitivity. When WBC of these patients were studied in the direct ACT assay, an additional augmentation of spACT effect by specific food antigens was observed. Surprisingly, Broncho-Vaxom (BX) did not inhibit or enhance spACT. However, BX has antagonistic activity toward direct ACT response in the dose-dependent concentration as previously reported. Our preliminary clinical experience leads us to believe that the spACT assay can serve as a useful clinical discriminator of potential responders versus non-responders to therapy with new agents, when WBC disintegration by autoinduction is involved.