Knocking down Cav1 calcium channels implicated in Th2 cell activation prevents experimental asthma.
BACKGROUND
Th2 cells orchestrate allergic asthma and the cytokines they produce (IL-4, IL-5, and IL-13) are deleterious in allergy. Therefore, it is important to identify key signaling molecules expressed by Th2 cells that are essential for their function. We have previously shown that dihydropyridines selectively modulate Th2 cell functions.


OBJECTIVE
Because dihydropyridines bind to and modulate voltage-dependent calcium (Ca(v)1) channel in excitable cells, we aimed at showing that Th2 cells selectively express functional Ca(v)1-related channels, the inhibition of which may prevent asthma.


METHODS
We looked for Ca(v)1 channel expression in Th2 and Th1 cells by real-time polymerase chain reaction and Western blotting. We sequenced the isoforms expressed by Th2 cells and tested whether Ca(v)1 antisense oligodeoxynucleotides (Ca(v)1AS) affected Ca(2+) signaling and cytokine production. Finally, we tested the effect of Ca(v)1AS in the passive asthma model by injection of ovalbumin-specific Th2 cells transfected with Ca(v)1AS into BALB/c mice challenged with intranasal ovalbumin and in the active model of asthma by intranasal delivery of Ca(v)1AS together with soluble ovalbumin in BALB/c mice previously immunized with ovalbumin in alum.


RESULTS
We show that mouse Th2 but not Th1 cells expressed Ca(v)1.2 and Ca(v)1.3 channels. Th2 cells transfected with Ca(v)1AS had impaired Ca(2+) signaling and cytokine production, and lost their ability to induce airway inflammation on adoptive transfer. Furthermore, intranasal administration of Ca(v)1AS suppressed airway inflammation and hyperreactivity in an active model of asthma.


CONCLUSIONS
These results indicate that Th2 cells selectively express Ca(v)1 channels that may be efficiently targeted in T lymphocytes to prevent experimental asthma.
Cabral
Marilena Djata
MD
INSERM U563, Centre de Physiopathologie de Toulouse Purpan, Place du Dr Baylac, Toulouse Cedex 3, France.
Paulet
Pierre-Emmanuel
PE
Robert
Virginie
V
Gomes
Bruno
B
Renoud
Marie-Laure
ML
Savignac
Magali
M
Leclerc
Catherine
C
Moreau
Marc
M
Lair
David
D
Langelot
Marie
M
Magnan
Antoine
A
Yssel
Hans
H
Mariamé
Bernard
B
Guéry
Jean-Charles
JC
Pelletier
Lucette
L
D000281:Administration, Intranasal; D000818:Animals; D001249:Asthma / Q000276:immunology / Q000517:prevention & control*; D015153:Blotting, Western / Q000379:methods; D002121:Calcium Channel Blockers / Q000276:immunology / Q000627:therapeutic use*; D015220:Calcium Channels / Q000187:drug effects* / Q000276:immunology; D051242:Caveolin 1 / Q000187:drug effects* / Q000276:immunology; D049109:Cell Proliferation / Q000187:drug effects; D004195:Disease Models, Animal; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D010047:Ovalbumin; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D018418:Th2 Cells / Q000276:immunology*; D015854:Up-Regulation / Q000276:immunology
D002121:Calcium Channel Blockers; D015220:Calcium Channels; C495541:Cav1 protein, mouse; D051242:Caveolin 1; D010047:Ovalbumin