TY - JOUR
T1 - Human eosinophils constitutively express nuclear factor of activated T cells p and c
AU - Seminario, Maria Cristina
AU - Guo, Jia
AU - Bochner, Bruce S.
AU - Beck, Lisa A.
AU - Georas, Steve N.
N1 - Funding Information:
From the Department of Medicine, Divisions of Clinical Immunology and Pulmonary Medicine, The Johns Hopkins Asthma and Allergy Center, Bal-timore. *Dr Seminario is currently affiliated with the National Institute of Aging, Bal-timore, Md. Supported in part by research grants from the National Institutes of Health and American Lung Association. Dr Seminario was the recipient of an Underrepresented Minority Investigator in Asthma and Allergy Award from the National Institutes of Health and the American Academy of Aller-gy, Asthma and Immunology. Received for publication April 5, 2000; revised September 19, 2000; accept-ed for publication September 21, 2000. Reprint requests: Steve N. Georas, MD, Rm. 4B.41, Johns Hopkins Asthma and Allergy Center, 5501 Hopkins Bayview Circle, Baltimore, MD 21224. Copyright © 2001 by Mosby, Inc. 0091-6749/2001 $35.00 + 0 1/83/111931 doi:10.1067/mai.2001.111931
PY - 2001/1
Y1 - 2001/1
N2 - Background: Eosinophils are now known to produce a variety of proinflammatory cytokines, although the molecular factors that regulate their production are poorly understood. The expression of almost all of the cytokines produced by eosinophils, including the proallergic cytokine IL-4, is now known to be regulated at the level of transcription by members of the nuclear factor of activated T cells (NFAT) family of transcription factors. Objective: We sought to characterize the expression of different NFAT proteins in resting and activated eosinophils. Methods: Nuclear and whole cell extracts were obtained from both peripheral blood eosinophils and those obtained from bronchoalveolar lavage fluid of asthmatic subjects after endobronchial allergen challenge. NFAT expression was determined by using immunoprecipitation and Western blot analysis, DNA-binding assays, and RT-PCR analysis of eosinophil mRNA. Results: Both peripheral blood and bronchoalveolar lavage fluid eosinophils expressed NFATp and NFATc protein. Unlike activated T cells, which express multiple NFATc isoforms, eosinophils preferentially express the approximately 85-kd isoform. In addition, eosinophils were found to constitutively express NFATc mRNA. A brief incubation with the TH2 cytokines IL-4 and IL-5 was sufficient to induce the nuclear translocation of NFATc. Eosinophil nuclear extracts contain multiple factors that can specifically recognize the IL-4 promoter P1 NFAT site in DNA-binding assays, including NFATp. Conclusion: NFATp and NFATc can regulate the expression of cytokines and other genes in eosinophils but appear to be regulated by a novel signal transduction mechanism in these cells.
AB - Background: Eosinophils are now known to produce a variety of proinflammatory cytokines, although the molecular factors that regulate their production are poorly understood. The expression of almost all of the cytokines produced by eosinophils, including the proallergic cytokine IL-4, is now known to be regulated at the level of transcription by members of the nuclear factor of activated T cells (NFAT) family of transcription factors. Objective: We sought to characterize the expression of different NFAT proteins in resting and activated eosinophils. Methods: Nuclear and whole cell extracts were obtained from both peripheral blood eosinophils and those obtained from bronchoalveolar lavage fluid of asthmatic subjects after endobronchial allergen challenge. NFAT expression was determined by using immunoprecipitation and Western blot analysis, DNA-binding assays, and RT-PCR analysis of eosinophil mRNA. Results: Both peripheral blood and bronchoalveolar lavage fluid eosinophils expressed NFATp and NFATc protein. Unlike activated T cells, which express multiple NFATc isoforms, eosinophils preferentially express the approximately 85-kd isoform. In addition, eosinophils were found to constitutively express NFATc mRNA. A brief incubation with the TH2 cytokines IL-4 and IL-5 was sufficient to induce the nuclear translocation of NFATc. Eosinophil nuclear extracts contain multiple factors that can specifically recognize the IL-4 promoter P1 NFAT site in DNA-binding assays, including NFATp. Conclusion: NFATp and NFATc can regulate the expression of cytokines and other genes in eosinophils but appear to be regulated by a novel signal transduction mechanism in these cells.
KW - Cytokines
KW - Eosinophils
KW - HMG1/Y
KW - Nuclear factor of activated T cells
KW - Transcriptional regulation
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U2 - 10.1067/mai.2001.111931
DO - 10.1067/mai.2001.111931
M3 - Article
C2 - 11150004
AN - SCOPUS:0035144977
VL - 107
SP - 143
EP - 152
JO - Journal of Allergy and Clinical Immunology
JF - Journal of Allergy and Clinical Immunology
SN - 0091-6749
IS - 1
ER -