Preferential Activation of Nuclear Factor of Activated T Cells c Correlates with Mouse Strain Susceptibility to Allergic Responses and Interleukin-4 Gene Expression

• Published in: American journal of respiratory cell and molecular biology Vol. 24; no. 1; pp. 58 - 65
• Main Authors: Keen, Judith Clancy, Sholl, Lynette, Wills-Karp, Marsha, Georas, Steve N
• Format: Journal Article
• Language: English
• Published: United States Am Thoracic Soc 01-01-2001; American Thoracic Society
• Subjects: Animals; Cell Nucleus - chemistry; Cell Nucleus - metabolism; Cells, Cultured; Concanavalin A - pharmacology; DNA-Binding Proteins - metabolism; Gene Expression Regulation - immunology; Hypersensitivity - immunology; Hypersensitivity - metabolism; Immunophenotyping; Interleukin-4 - biosynthesis; Interleukin-4 - genetics; Macromolecular Substances; Male; Mice; Mice, Inbred A; Mice, Inbred C3H; NFATC Transcription Factors; Nuclear Proteins; Promoter Regions, Genetic - genetics; Sequence Analysis, DNA; Species Specificity; Spleen - cytology; Spleen - drug effects; Spleen - metabolism; Stimulation, Chemical; T-Lymphocytes - cytology; T-Lymphocytes - immunology; T-Lymphocytes - metabolism; Transcription Factors - isolation & purification; Transcription Factors - metabolism; Transcription, Genetic - genetics
• ISSN: 1044-1549; 1535-4989
• DOI: 10.1165/ajrcmb.24.1.3870

Dysregulated expression of the T helper 2 cytokine interleukin (IL)-4 is thought to play a fundamental role in the pathogenesis of allergic asthma. The molecular basis for dysregulated IL-4 production is not well understood. We analyzed in detail the molecular factors involved in regulating IL-4 transcription in a well-characterized mouse model. In this model, A/J mice developed allergen-induced IL-4 cytokine gene expression, airway inflammation, and hyperresponsiveness, whereas C3H/HeJ (C3H) mice did not. Here we report that isolated splenocytes from A/J and C3H mice stimulated ex vivo with concanavalin A reproduced the cytokine phenotype observed in the airway after antigen challenge. We hypothesized that differences in splenocyte IL-4 production involved either polymorphisms in regulatory IL-4 promoter regions, or the expression and activation of transcription factors necessary for promoter transactivation in a strain-dependent manner. To address these questions, we first sequenced ~ 700 base pairs containing well-characterized IL-4 promoter regulatory elements using genomic DNA obtained from C3H and A/J mice. Next, we used electrophoretic mobility shift assays with relevant IL-4 promoter sequences to screen nuclear extracts isolated from A/J and C3H splenocytes for functional transcriptional factor complexes. Here we show that susceptibility to antigen-induced airway hyperresponsiveness is not due to polymorphisms in the IL-4 promoter, but is associated with preferential expression of nuclear factor of activated T cells c in splenocyte nuclear extracts obtained from A/J mice. In conclusion, our data link dysregulated activation of a specific transcription factor with susceptibility to allergic airway inflammation.