SLAT regulates Th1 and Th2 inflammatory responses by controlling Ca2+/NFAT signaling.
SWAP-70-like adapter of T cells (SLAT) is a novel guanine nucleotide exchange factor for Rho GTPases that is upregulated in Th2 cells, but whose physiological function is unclear. We show that SLAT(-/-) mice displayed a developmental defect at one of the earliest stages of thymocyte differentiation, the double-negative 1 (DN1) stage, leading to decreased peripheral T cell numbers. SLAT(-/-) peripheral CD4(+) T cells demonstrated impaired TCR/CD28-induced proliferation and IL-2 production, which was rescued by the addition of exogenous IL-2. Importantly, SLAT(-/-) mice were grossly impaired in their ability to mount not only Th2, but also Th1-mediated lung inflammatory responses, as evidenced by reduced airway neutrophilia and eosinophilia, respectively. Levels of Th1 and Th2 cytokine in the lungs were also markedly reduced, paralleling the reduction in pulmonary inflammation. This defect in mounting Th1/Th2 responses, which was also evident in vitro, was traced to a severe reduction in Ca(2+) mobilization from ER stores, which consequently led to defective TCR/CD28-induced translocation of nuclear factor of activated T cells 1/2 (NFATc1/2). Thus, SLAT is required for thymic DN1 cell expansion, T cell activation, and Th1 and Th2 inflammatory responses.
Bécart
Stéphane
S
Division of Cell Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California 92037, USA.
Charvet
Céline
C
Canonigo Balancio
Ann J
AJ
De Trez
Carl
C
Tanaka
Yoshihiko
Y
Duan
Wei
W
Ware
Carl
C
Croft
Michael
M
Altman
Amnon
A
D000818:Animals; D018106:CD28 Antigens / Q000235:genetics / Q000276:immunology; D020013:Calcium Signaling / Q000235:genetics / Q000276:immunology*; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D049109:Cell Proliferation; D004268:DNA-Binding Proteins / Q000172:deficiency / Q000276:immunology*; D020662:Guanine Nucleotide Exchange Factors; D007249:Inflammation / Q000235:genetics / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology; D051379:Mice; D018345:Mice, Knockout; D050778:NFATC Transcription Factors / Q000235:genetics / Q000276:immunology*; D009687:Nuclear Proteins / Q000172:deficiency / Q000276:immunology*; D011014:Pneumonia / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D011657:Pulmonary Eosinophilia / Q000235:genetics / Q000276:immunology / Q000473:pathology; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology* / Q000473:pathology; D018418:Th2 Cells / Q000276:immunology* / Q000473:pathology; D013950:Thymus Gland / Q000276:immunology / Q000473:pathology
D018106:CD28 Antigens; D004268:DNA-Binding Proteins; D020662:Guanine Nucleotide Exchange Factors; D007376:Interleukin-2; D050778:NFATC Transcription Factors; D009687:Nuclear Proteins; D011948:Receptors, Antigen, T-Cell; C494005:Nfatc1 protein, mouse; C494007:Nfatc2 protein, mouse; C473249:Def6 protein, mouse