MESSENGER-RNA EXPRESSION OF THE CYTOKINE GENE-CLUSTER, INTERLEUKIN-3 (IL-3), IL-4, IL-5, AND GRANULOCYTE MACROPHAGE COLONY-STIMULATING FACTOR, IN ALLERGEN-INDUCED LATE-PHASE CUTANEOUS REACTIONS IN ATOPIC SUBJECTS

Cryostat sections from skin biopsies from 24-h allergen-induced late-phase cutaneous reactions (LPR) in 14 human atopic subjects were hybridized with S-35-labeled RNA probes for a number of cytokines. mRNA was detected for interleukin 3 (IL-3) (8/14), IL-4 (10/14), IL-5 (11/14), and granulocyte/macrophage colony-stimulating factor (GM-CSF) (13/14). Only 5 of 14 gave hybridization signals for IL-2, and 0 of 14 for interferon-gamma. Biopsies from diluent controls gave only occasional weak signals. These results suggest that cells infiltrating the site of the 24-h LPR transcribe mRNA for the IL-3, IL-4, IL-5, and GM-CSF gene cluster and support the hypothesis that atopy is associated with preferential activation of cells having a similar cytokine profile to the murine T helper type 2 subset.