title: S1P-induced airway smooth muscle hyperresponsiveness and lung inflammation in vivo: molecular and cellular mechanisms.
abstract: OBJECTIVE
  Sphingosine-1-phosphate (S1P) has been shown to be involved in the asthmatic disease as well in preclinical mouse experimental models of this disease. The aim of this study was to understand the mechanism(s) underlying S1P effects on the lung.
  
  
  METHODS
  BALB/c, mast cell-deficient and Nude mice were injected with S1P (s.c.) on days 0 and 7. Functional, molecular and cellular studies were performed.
  
  
  RESULTS
  S1P administration to BALB/c mice increased airway smooth muscle reactivity, mucus production, PGD2 , IgE, IL-4 and IL-13 release. These features were associated to a higher recruitment of mast cells to the lung. Mast cell-deficient Kit (W) (-sh/) (W) (-sh) mice injected with S1P did not display airway smooth muscle hyper-reactivity. However, lung inflammation and IgE production were still present. Treatment in vivo with the anti-CD23 antibody B3B4, which blocks IgE production, inhibited both S1P-induced airway smooth muscle reactivity in vitro and lung inflammation. S1P administration to Nude mice did not elicit airway smooth muscle hyper-reactivity and lung inflammation. Naïve (untreated) mice subjected to the adoptive transfer of CD4+ T-cells harvested from S1P-treated mice presented all the features elicited by S1P in the lung.
  
  
  CONCLUSIONS
  S1P triggers a cascade of events that sequentially involves T-cells, IgE and mast cells reproducing several asthma-like features. This model may represent a useful tool for defining the role of S1P in the mechanism of action of currently-used drugs as well as in the development of new therapeutic approaches for asthma-like diseases.
authors.affiliation: Dipartimento di Farmacia, Università di Napoli Federico II, Napoli, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Roviezzo
authors.forename: R
authors.initials: R
authors.lastname: Sorrentino
authors.forename: A
authors.initials: A
authors.lastname: Bertolino
authors.forename: L
authors.initials: L
authors.lastname: De Gruttola
authors.forename: M
authors.initials: M
authors.lastname: Terlizzi
authors.forename: A
authors.initials: A
authors.lastname: Pinto
authors.forename: M
authors.initials: M
authors.lastname: Napolitano
authors.forename: G
authors.initials: G
authors.lastname: Castello
authors.forename: B
authors.initials: B
authors.lastname: D'Agostino
authors.forename: A
authors.initials: A
authors.lastname: Ianaro
authors.forename: R
authors.initials: R
authors.lastname: Sorrentino
authors.forename: G
authors.initials: G
authors.lastname: Cirino
mesh_terms: D000818:Animals; D016535:Bronchial Hyperreactivity / Q000097:blood / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D007073:Immunoglobulin E / Q000097:blood; D018793:Interleukin-13 / Q000276:immunology; D015847:Interleukin-4 / Q000276:immunology; D008246:Lysophospholipids / Q000276:immunology*; D008407:Mast Cells / Q000276:immunology; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D008819:Mice, Nude; D011014:Pneumonia / Q000097:blood / Q000276:immunology*; D015230:Prostaglandin D2 / Q000097:blood; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000276:immunology
chemical_list: D018793:Interleukin-13; D008246:Lysophospholipids; D015847:Interleukin-4; C060506:sphingosine 1-phosphate; D007073:Immunoglobulin E; D013110:Sphingosine; D015230:Prostaglandin D2