V H genes expressed in peripheral blood IgE‐producing B cells from patients with atopic dermatitis

In this study we analysed the V H genes expressed in IgE‐producing peripheral B cells in two patients with severe atopic dermatitis. We found a diverse antibody repertoire containing V H genes of five different V H families, no V H 2 and 7 genes, with no biased usage of one particular V H gene family. Some V H germ‐line segments were found to be used several times within the ε transcripts ( V3–23, V3–30 ). Comparison of the IgE‐encoding V H genes with the respective germ‐line elements revealed the expression of nearly germ‐line identical as well as somatically mutated V H genes. In these latter V H genes base substitutions were distributed over both complementarity determining and framework regions. Because of the similarities between the IgE committed B cell repertoire in atopic patients and the peripheral B cell repertoire in non‐atopic individuals we conclude that the atopic V H gene repertoire probably reflects the result of an increased class switch of polyclonal B cells, including virgin and mature B cells, in response to a Th2 cytokine profile.