STUDY OF IGE-DEPENDENT SULPHIDOLEUKOTRIENE CELLULAR RELEASABILITY

Cellular releasability of mediators, as termed by Lichtenstein and Con roy (1), can be triggered by interaction with allergens, anti-IgE anti bodies or other agonists. Genetic factors can also influence the cell releasability. We studied 104 subjects, including 92 atopic patients ( 62 sensitive to D. pteronyssinus and 54 sensitive to Lolium perenne) a nd 12 healthy controls. Sulphidoleukotriene (sLT) production was measu red after allergen and anti-IgE stimulus with CAST-ELISA, and histamin e release using a fluorometric method. We found a significant sLT prod uction after anti-IgE stimulation, higher than in basal conditions wit h medium alone. The sLT production was also significantly higher in se nsitive patients than in healthy controls. We found 14.5% of healthy a nd atopic subjects to be non-responders to anti-IgE stimulus. We also found a positive and significant correlation between sLT production an d histamine release. Moreover, we observed a significant positive corr elation between IgE-dependent and antigen-specific sLT release. We als o noticed a decrease in sLT production and a decrease in histamine rel ease with aging. Male patients had a sLT production significantly high er than female patients. With respect to clinical diagnosis, the group of patients with rhinitis had the highest mediator production. Finall y, pollinic patients studied during the spring had a higher sLT produc tion to anti-IgE than those studied out of this season. We conclude th at quantification of sLT production after anti-IgE stimulation is a us eful method to study cell releasability of mediators and that such rel easability is higher in atopic patients than in healthy donors. We mus t emphasize the usefulness in allergy diagnosis of relying not only on the use of methods demonstrating the existence of sensitization to an allergen, but also of techniques able to quantify the ability to resp ond to that allergen. In this way we would be able to evaluate the cli nical and immunological evolution of patients and to follow up the eff icacy of their treatment.