VH genes expressed in peripheral blood IgE-producing B cells from patients with atopic dermatitis

Abstract

SUMMARYIn 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 e 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.

Unlike in Children with Allergic Asthma, IgE Transcripts from Preschool Children with Atopic Dermatitis Display Signs of Superantigen-Driven Activation

“…An excessive usage of V H families that are normally infrequently used in secondary immune responses might hence be indicative of a superantigen-like activation of B cells (1). However, not all studies on immunogenetic characteristic of the IgE response in atopic eczema found a biased V H usage (7,8).…”

“…Although some of these aspects have already been addressed in studies with adult patients [ (7)(8)(9), reviewed in Refs. 1 and 10], hitherto the molecular characteristics of the IgE response have not been analyzed systematically in children with atopic dermatitis, even though this specific age group is of particular interest for the evolvement of the IgE response in atopic dermatitis.…”

Local Somatic Hypermutation and Class Switch Recombination in the Nasal Mucosa of Allergic Rhinitis Patients

“…The selected patients exhibited serum IgE levels Ͼ200 IU/ml to ensure success in RT-PCR amplification of V H regions (27,33). Fifteen sequences were analyzed from the nasal biopsy samples of each patient.…”

Characterization of VHε gene expressed in PBL from children with atopic diseases: detection of homologous VH1–69 derived transcripts from three unrelated patients

“…With a new approach using V H family specific primers, the IgE V H repertoire of patients with allergic disease have been analyzed [12][13][14][15]. The dominance of V H 5 genes from asthma patients was observed [12,13], on the other hand, no bias for the usage of IgE V H was detected in AD patients [14].…”