Expression of eicosanoid receptors subtypes and eosinophilic inflammation: implication on chronic rhinosinusitis

BACKGROUND: Eicosanoid receptors are G-protein-coupled receptors playing an important immunomodulatory role in airway diseases. However, there is little information on the expression of these receptors and their link with eosinophilic inflammation in paranasal sinus diseases. We aimed with this study to investigate the tissue expression of leukotrienes and prostaglandin E2 receptors in chronic rhinosinusitis patients and the link of this regulation with eosinophilic inflammation. METHODS: Samples were prepared from nasal tissue of patients with chronic rhinosinusitis without nasal polyps (CRS, n = 11), with nasal polyps (CRS-NP, n = 13) and healthy subjects (Controls, n = 6). mRNA expression of CysLT(1), CysLT(2), BLT(1), BLT(2), E-prostanoid receptors (EP(1), EP(2), EP(3), EP(4)) and sol-IL-5Rα was determined by real-time PCR. Concentrations of PGE2, LTC4/D4/E4, LTB4 and sol-IL-5Rα were determined by ELISA and of ECP by ImmunoCap. Protein expression and tissue localization of eicosanoid receptors and activated eosinophils were evaluated by immunohistochemistry. RESULTS: CysLT(1 )mRNA expression was significantly increased in CRS-NP compared to CRS and controls, and CRS compared to controls, whereas CysLT(2 )mRNA was enhanced in both CRS groups without differences between them. Levels of both receptors correlated to the number of activated eosinophils, sol-IL-5Rα, ECP and LTC(4)/D(4)/E(4 )concentrations in the disease groups. PGE(2 )protein concentrations and prostanoid receptors EP(1 )and EP(3 )were down-regulated in the CRS-NP tissue vs. CRS and controls, whereas EP(2 )and EP(4 )expression was enhanced in CRS and CRS-NP patients vs. controls. No differences in BLT receptors were observed between patients and controls. CONCLUSION: CyLTs receptors are up-regulated in nasal polyp tissue and their expression correlate with eosinophilic inflammation supporting previous results. Eicosanoid receptors mRNA pattern observed suggests that down-regulation of EP(1 )and EP(3 )in CRS-NP and up-regulation EP(2 )and EP(4 )in CRS and CRS-NP groups may have some role in the development of the diseases and their regulation may not be directly linked to eosinophil activation but involve post-transcriptional events mainly related to other inflammatory cell sources

Transcription Regulation of Sex-Biased Genes during Ontogeny in the Malaria Vector Anopheles gambiae

In Anopheles gambiae, sex-regulated genes are responsible for controlling gender dimorphism and are therefore crucial in determining the ability of female mosquitoes to transmit human malaria. The identification and functional characterization of these genes will shed light on the sexual development and maturation of mosquitoes and provide useful targets for genetic control measures aimed at reducing mosquito fertility and/or distorting the sex ratio

Social Transfer of Pathogenic Fungus Promotes Active Immunisation in Ant Colonies

Social contact with fungus-exposed ants leads to pathogen transfer to healthy nest-mates, causing low-level infections. These micro-infections promote pathogen-specific immune gene expression and protective immunization of nest-mates

Salivary Biomarkers for Detection of Systemic Diseases

Peer reviewe

CalpA, a Drosophila calpain homolog specifically expressed in a small set of nerve, midgut, and blood cells.

Calpains are calcium-dependent proteases believed to participate in calcium-regulated signal pathways in cells. Ubiquitous calpains as well as tissue-specific calpains have been found in vertebrates. We isolated cDNA clones for a highly tissue-specific calpain gene from Drosophila melanogaster, CalpA, at 56C-D on the second chromosome. The expression of the CalpA gene product was monitored by using a specific antiserum directed against the product expressed by one cDNA clone. The encoded protein is found in a few neurons in the central nervous system, in scattered endocrine cells in the midgut, and in blood cells. In the blood cell line mbn-2, calpain is associated with a granular component in the cytoplasm. The expression of this protein is more restricted than that of the corresponding transcripts, which are widely distributed in the central nervous system, digestive tract, and other tissues. The sequence of CalpA is closely related to that of vertebrate calpains, but an additional segment is inserted in the calmodulin-like carboxy-terminal domain. This insert contains a hydrophobic region that may be involved in membrane attachment of the enzyme. Differential splicing also gives rise to a minor transcript that lacks the calmodulin-like domain