Comparison of diversity and function of house dust mite-specific T lymphocyte clones from atopic and non-atopic donors.

Panels of CD4+CD8- T lymphocyte clones (TLC), specific for house dust mite Dermatophagoides pteronyssinus (Dp) proteins, were generated from the peripheral blood of an atopic Dp-allergic donor (AD), suffering from severe atopic dermatitis, and a histocompatible non-atopic donor (NAD). We studied the diversity of TLC within these two panels in search for the possible occurrence of dominant clone types with properties that might be characteristic for the atopic or non-atopic state. TLC with specificities for at least four different Dp proteins were found within the panel from AD "L" and for at least three different Dp proteins within the panel from NAD "K". In addition, both panels showed a considerable but comparable restriction diversity within HLA-DR. Despite the diversity within the panels, all Dp-specific TLC from AD were found to produce IL 4, after HLA class II-restricted Dp-specific stimulation, whereas the TLC from NAD produced no or only minimal amounts of this lymphokine. Only supernatants from stimulated AD TLC could induce IgE secretion by B cells from NAD. Conclusively, these observations do not give evidence for the occurrence of an abnormal Dp-specific T cell repertoire in AD, but rather suggest aberrant secretion of the IgE-inducing lymphokine IL 4 by CD4+ Dp-specific T cells from AD.