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Role of Lysophosphatidylcholine in Allergic Airway Disease Manifestation
AB198 Abstracts
643
J ALLERGY CLIN IMMUNOL FEBRUARY 2016
SIRT1 Attenuates Nasal Polypogenesis By Suppressing Epithelial-to-Mesenchymal Transition
SUNDAY
Hyun-Woo Shin1,2, Mingyu Lee1, Dae Woo Kim, MD3,4; 1Seoul National University College of Medicine, Department of Pharmacology and Biomedical Sciences, South Korea, 2Seoul National University Hospital, Department of Otorhinolaryngology-Head and Neck Surgery, 3Seoul National University Hospital and Boramae Medical Center, South Korea, 4 Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul, South Korea. RATIONALE: Nasal polyps imply a refractory clinical course in chronic rhinosinusitis (CRS). Previously, we showed that hypoxia-inducible factor (HIF)-1 could mediate nasal polypogenesis via epithelial-to-mesenchymal transition (EMT). SIRT1, a histone deacetylase, reportedly suppresses the transcriptional activity of HIF-1. Thus, the authors hypothesized that SIRT1 attenuates nasal polyposis by inhibiting HIF-1-induced EMT. METHODS: The effects of SIRT1 on nasal polypogenesis were investigated in previously developed murine models. Immunohistochemistry, immunoblotting and immunoprecipitation were done to evaluate SIRT1 level, EMT and hypoxic markers in human nasal epithelial cells or sinonasal tissues from the mice and the CRS patients with or without nasal polyp. RESULTS: SIRT1 transgenic (TG) mice had significantly fewer mucosal lesions with epithelial disruption and fewer nasal polyps than wild-type (WT) mice. In addition, resveratrol (a SIRT1 activator) treatment suppressed nasal polypogenesis in WT mice; however, sirtinol (a SIRT1 inhibitor) administration increased the polyp burden in SIRT1 TG mice. In CRS sinonasal specimens, SIRT1 was downregulated in the mucosa from patients with polyps as compared with patients without polyps. SIRT1 overexpression or activation reversed hypoxia-induced EMT in human nasal epithelial cells (hNECs). The intranasal transfection of a sh-SIRT1 lentiviral vector induced more nasal polypoid lesions in SIRT1 TG mice. Finally, mucosal extracts from CRS without nasal polyps increased SIRT1 expression in nasal epithelial cells, and those from CRS with nasal polyps did not. CONCLUSIONS: SIRT1 suppressed nasal polyp formation, possibly due to inhibition of HIF-1-induced EMT. Thus, nasal epithelium SIRT1 may be a therapeutic target for nasal polyps.
644
Thymic Stromal Lymphopoietin Prostaglandin D2 Generation in Exacerbated Respiratory Disease
Controls Aspirin-
Kathleen M. Buchheit, MD1,2, Katherine N. Cahill, MD1,2, Howard Katz, PhD1,2, Katherine Murphy3, Chunli Feng, MD4, Kathleen LeeSarwar1,2, Juying Lai1, Neil Bhattacharyya, MD2,5, Elliot Israel, MD, FAAAAI5, Joshua A. Boyce, MD, FAAAAI1,2, Tanya M. Laidlaw, MD, FAAAAI4; 1Brigham and Women’s Hospital, Division of Rheumatology, Immunology and Allergy, Boston, MA, 2Harvard Medical School, Boston, MA, 3Brigham and Women’s Hospital, 4Brigham and Women’s Hospital, Division of Rheumatology, Immunology, and Allergy, Boston, MA, 5 Brigham and Women’s Hospital, Boston, MA. RATIONALE: Prostaglandin D2 (PGD2) is the dominant cyclooxygenase product of mast cells and is an effector of aspirin-induced respiratory reactions in aspirin-exacerbated respiratory disease (AERD). We evaluated the role of the innate cytokine thymic stromal lymphopoietin (TSLP) acting on mast cells to generate PGD2 and facilitate tissue eosinophilia and nasal polyposis in AERD. METHODS: Urinary eicosanoids were measured in aspirin-tolerant controls and patients with AERD. Nasal polyp specimens from subjects with AERD and chronic rhinosinusitis were analyzed via qPCR, western blot, and immunohistochemistry. Human cord blood and peripheral blood-derived mast cells were stimulated with TSLP in vitro to assess PGD2 generation. RESULTS: Urinary levels of a stable PGD2 metabolite (uPGD-M) were 2-fold higher in subjects with AERD relative to controls, and increased
further during aspirin-induced reactions. Peak uPGD-M levels during aspirin reactions correlated with reductions in blood eosinophil counts and lung function, and increases in nasal congestion. Mast cells sorted from nasal polyps expressed PGD2 synthase (hPGDS) mRNA at higher levels than did eosinophils sorted from the same tissue. Whole nasal polyp TSLP mRNA expression correlated with mRNA encoding hPGDS (r 5 .75), the mast cell-specific marker carboxypeptidase A3 (r 5 .74), and uPGD-M (r50.74). The cleaved, active form of TSLP was increased in AERD nasal polyps relative to aspirin-tolerant controls. Recombinant TSLP induced PGD2 generation by cultured human mast cells. CONCLUSIONS: Our study demonstrates that mast cell-derived PGD2 is a major effector of type 2 immune responses driven by TSLP, and suggests that dysregulation of this system contributes to the pathophysiology of AERD.
645
Role of Lysophosphatidylcholine in Allergic Airway Disease Manifestation
Preeti Bansal1, Shailendra N. Gaur, MD, FAAAAI2, Naveen Arora, PhD3; 1CSIR Institute of Genomics and Integrative Biology, New Delhi, India, 2University Of Delhi, Delhi, India, 3CSIR- Institute of Genomics and Integrative Biology, Delhi, India. RATIONALE: Secretory phospholipase A2 (sPLA2) is involved in allergic and inflammatory response and hydrolyses phosphatidylcholine (PC) to lysophosphatidylcholine (LPC). LPC levels increase in BALF and sera of asthma and rhinitis patients. In the present study the role of LPC was studied in mouse model of allergic airway disease. METHODS: Mice were immunized with cockroach extract (CE) and sPLA2 inhibitor was given to block LPC release. AHR, TLC, DLC, lung inflammation, Th2 type cytokines, sPLA2 activity and LPC were analysed. Mice were given LPC to study its role in allergic disease manifestation, with or without CE sensitization. The involvement of NKT cells in LPC induced response was studied by anti-CD1d antibody before CE/LPC exposure. RESULTS: CE challenge increased AHR, TLC, DLC, lung inflammation, Th2 type cytokines, sPLA2 activity and LPC level significantly as compared to control mice (p<0.05). sPLA2 inhibitor blocked its activity, LPC release and decreased AHR, and inflammatory parameters significantly (p<0.05). LPC exposure with or without CE sensitization increased the AHR, TLC, DLC, lung inflammation, and Th2 type cytokines significantly (p<0.05) demonstrating the role of LPC in allergic disease manifestation. CE challenge or LPC exposure increased LY49C+TCRb+ NKT cells in BALF and spleen significantly (p<0.05), which was blocked by anti-CD1d antibody. It also decreased AHR and allergic inflammation parameters significantly (p<0.05). CONCLUSIONS: Allergen challenge increases sPLA2 activity and LPC release resulting in allergic airway disease manifestation via CD1drestricted LY49C+TCRb+ NKT cells.
643
J ALLERGY CLIN IMMUNOL FEBRUARY 2016
SIRT1 Attenuates Nasal Polypogenesis By Suppressing Epithelial-to-Mesenchymal Transition
SUNDAY
Hyun-Woo Shin1,2, Mingyu Lee1, Dae Woo Kim, MD3,4; 1Seoul National University College of Medicine, Department of Pharmacology and Biomedical Sciences, South Korea, 2Seoul National University Hospital, Department of Otorhinolaryngology-Head and Neck Surgery, 3Seoul National University Hospital and Boramae Medical Center, South Korea, 4 Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul, South Korea. RATIONALE: Nasal polyps imply a refractory clinical course in chronic rhinosinusitis (CRS). Previously, we showed that hypoxia-inducible factor (HIF)-1 could mediate nasal polypogenesis via epithelial-to-mesenchymal transition (EMT). SIRT1, a histone deacetylase, reportedly suppresses the transcriptional activity of HIF-1. Thus, the authors hypothesized that SIRT1 attenuates nasal polyposis by inhibiting HIF-1-induced EMT. METHODS: The effects of SIRT1 on nasal polypogenesis were investigated in previously developed murine models. Immunohistochemistry, immunoblotting and immunoprecipitation were done to evaluate SIRT1 level, EMT and hypoxic markers in human nasal epithelial cells or sinonasal tissues from the mice and the CRS patients with or without nasal polyp. RESULTS: SIRT1 transgenic (TG) mice had significantly fewer mucosal lesions with epithelial disruption and fewer nasal polyps than wild-type (WT) mice. In addition, resveratrol (a SIRT1 activator) treatment suppressed nasal polypogenesis in WT mice; however, sirtinol (a SIRT1 inhibitor) administration increased the polyp burden in SIRT1 TG mice. In CRS sinonasal specimens, SIRT1 was downregulated in the mucosa from patients with polyps as compared with patients without polyps. SIRT1 overexpression or activation reversed hypoxia-induced EMT in human nasal epithelial cells (hNECs). The intranasal transfection of a sh-SIRT1 lentiviral vector induced more nasal polypoid lesions in SIRT1 TG mice. Finally, mucosal extracts from CRS without nasal polyps increased SIRT1 expression in nasal epithelial cells, and those from CRS with nasal polyps did not. CONCLUSIONS: SIRT1 suppressed nasal polyp formation, possibly due to inhibition of HIF-1-induced EMT. Thus, nasal epithelium SIRT1 may be a therapeutic target for nasal polyps.
644
Thymic Stromal Lymphopoietin Prostaglandin D2 Generation in Exacerbated Respiratory Disease
Controls Aspirin-
Kathleen M. Buchheit, MD1,2, Katherine N. Cahill, MD1,2, Howard Katz, PhD1,2, Katherine Murphy3, Chunli Feng, MD4, Kathleen LeeSarwar1,2, Juying Lai1, Neil Bhattacharyya, MD2,5, Elliot Israel, MD, FAAAAI5, Joshua A. Boyce, MD, FAAAAI1,2, Tanya M. Laidlaw, MD, FAAAAI4; 1Brigham and Women’s Hospital, Division of Rheumatology, Immunology and Allergy, Boston, MA, 2Harvard Medical School, Boston, MA, 3Brigham and Women’s Hospital, 4Brigham and Women’s Hospital, Division of Rheumatology, Immunology, and Allergy, Boston, MA, 5 Brigham and Women’s Hospital, Boston, MA. RATIONALE: Prostaglandin D2 (PGD2) is the dominant cyclooxygenase product of mast cells and is an effector of aspirin-induced respiratory reactions in aspirin-exacerbated respiratory disease (AERD). We evaluated the role of the innate cytokine thymic stromal lymphopoietin (TSLP) acting on mast cells to generate PGD2 and facilitate tissue eosinophilia and nasal polyposis in AERD. METHODS: Urinary eicosanoids were measured in aspirin-tolerant controls and patients with AERD. Nasal polyp specimens from subjects with AERD and chronic rhinosinusitis were analyzed via qPCR, western blot, and immunohistochemistry. Human cord blood and peripheral blood-derived mast cells were stimulated with TSLP in vitro to assess PGD2 generation. RESULTS: Urinary levels of a stable PGD2 metabolite (uPGD-M) were 2-fold higher in subjects with AERD relative to controls, and increased
further during aspirin-induced reactions. Peak uPGD-M levels during aspirin reactions correlated with reductions in blood eosinophil counts and lung function, and increases in nasal congestion. Mast cells sorted from nasal polyps expressed PGD2 synthase (hPGDS) mRNA at higher levels than did eosinophils sorted from the same tissue. Whole nasal polyp TSLP mRNA expression correlated with mRNA encoding hPGDS (r 5 .75), the mast cell-specific marker carboxypeptidase A3 (r 5 .74), and uPGD-M (r50.74). The cleaved, active form of TSLP was increased in AERD nasal polyps relative to aspirin-tolerant controls. Recombinant TSLP induced PGD2 generation by cultured human mast cells. CONCLUSIONS: Our study demonstrates that mast cell-derived PGD2 is a major effector of type 2 immune responses driven by TSLP, and suggests that dysregulation of this system contributes to the pathophysiology of AERD.
645
Role of Lysophosphatidylcholine in Allergic Airway Disease Manifestation
Preeti Bansal1, Shailendra N. Gaur, MD, FAAAAI2, Naveen Arora, PhD3; 1CSIR Institute of Genomics and Integrative Biology, New Delhi, India, 2University Of Delhi, Delhi, India, 3CSIR- Institute of Genomics and Integrative Biology, Delhi, India. RATIONALE: Secretory phospholipase A2 (sPLA2) is involved in allergic and inflammatory response and hydrolyses phosphatidylcholine (PC) to lysophosphatidylcholine (LPC). LPC levels increase in BALF and sera of asthma and rhinitis patients. In the present study the role of LPC was studied in mouse model of allergic airway disease. METHODS: Mice were immunized with cockroach extract (CE) and sPLA2 inhibitor was given to block LPC release. AHR, TLC, DLC, lung inflammation, Th2 type cytokines, sPLA2 activity and LPC were analysed. Mice were given LPC to study its role in allergic disease manifestation, with or without CE sensitization. The involvement of NKT cells in LPC induced response was studied by anti-CD1d antibody before CE/LPC exposure. RESULTS: CE challenge increased AHR, TLC, DLC, lung inflammation, Th2 type cytokines, sPLA2 activity and LPC level significantly as compared to control mice (p<0.05). sPLA2 inhibitor blocked its activity, LPC release and decreased AHR, and inflammatory parameters significantly (p<0.05). LPC exposure with or without CE sensitization increased the AHR, TLC, DLC, lung inflammation, and Th2 type cytokines significantly (p<0.05) demonstrating the role of LPC in allergic disease manifestation. CE challenge or LPC exposure increased LY49C+TCRb+ NKT cells in BALF and spleen significantly (p<0.05), which was blocked by anti-CD1d antibody. It also decreased AHR and allergic inflammation parameters significantly (p<0.05). CONCLUSIONS: Allergen challenge increases sPLA2 activity and LPC release resulting in allergic airway disease manifestation via CD1drestricted LY49C+TCRb+ NKT cells.