INICSA   23916
INSTITUTO DE INVESTIGACIONES EN CIENCIAS DE LA SALUD
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Bronchiolar epithelium participation in the neonatal prevetion of asthma.
Autor/es:
GARCÍA LN, SCALERANDI MV, URIBE ECHEVARRÍA EM, LEIMGRUBER C, QUINTAR AA AND MALDONADO CA
Reunión:
Congreso; IMMUNOCOLOMBIA 2015 - 11th Congress of the Latin American Association of Immunology; 2015
Resumen:
Although the susceptibly for allergic disease has a hereditary element, the current worldwide raise in asthma prevalence have evidenced that environmental changes are also implicated. A possible explanation for this phenomenon has been suggested by the socalled hygiene hypothesis, based on epidemiological studies. This hypothesis states that the urban hygienic conditions skip the earlylife exposure to microbes hence they are clue to promote innate immune activation by signaling through the Tolllike receptors (TLRs) and thus preventing the allergic response. Even though the way this microbial stimuli exert such prevention is still not well know, the use of murine models have highlighted the possible compensatory mechanisms involved. Nowadays, a growing body of genetic and clinical data highlights the need to consider the role of structural components of the airway in the onset and development of asthma. In particular the epithelium is central, because this is the site where an inflammatory or noninflammatory decision must first be made to inhaled allergen. In these sense, at bronchiolar level, the epithelial Club cells (CC) are key contributors for local homeostasis. Under normal conditions these cells detoxify xenobiotics as well as oxidant gasses, participate in mucociliary clearance of environmental agents and through their pluripotencial capacity, they are involved in the epithelial maintenance and repair. In addition, these cells modulate the local inflammation by secreting the antiinflammatory Club cell secretory protein (CCSP) and participate in the innate immune response through the secretion of the collectins surfactant protein (SP) A and D as well as several cytokines and chemokines. Among these mediators, it has been reported that both, CCSP and SPD, exhibited Th2 immunomodulatory effect.Beside these lung protective functions, CC also have been linked to the allergic remodeling process of asthma, since they are the principal cells to produce eotaxin and undergo mucus metaplasia in response to Th2 inflammation. Previous results of our laboratory indicate that this mucous transdifferentiation induced the diminution of the normal SPD and CCSP content, while the intranasal stimulus with Lipopolysaccharide (LPS) increase the Club cell expression of these proteins as well as the receptor TLR4. OBJECTIVE: The aim of this study was to modify the microbial environment to which lung epithelium of newborn Balb/c mice are exposed and study the possible influence on the subsequent development of airway allergic inflammation to Ovolabumin (OVA). MATERIAL AND METHODS Offspring Balb/c mice were intranasal (in.)pre exposed to 5μl of PBS or E. Coli LipopolysaccharideLPS (200mg/ml), 3 times per week , between days 3 to 13 after birth. At the age of 4 and 6 weeks, female mice were systemically sensitized by means of 100μl intraperitoneal injection of OVA/Alumm (1mg/1mg/ml). Then, mice were assigned into groups (n=10) and in. challenged on 10 consecutive days with OVA (1mg/ml) (LPSn/OVA and PBSn/OVA group) or vehicle (LPSn and PBSn group). Twenty four hours later animals were sacrificed, bronchoalveolar lavages (BAL) were performed and lung tissues were obtained. After centrifugation BAL supernatant were reserved at 20°C for ELISA assay while pellet were used for flow cytometry (FC) analysis and differential cell count in cytospin slide with May GrünwaldAbout Submit Journals Research Topics 3 My frontiersSearch for articles, people, events and more. MARIA SCALERANDIEVENT ABSTRACT19/8/2015 Frontiers | Manage Abstracts | My Submissions | All Abstractshttp://www.frontiersin.org/Journal/MySubmissionViewDetails.aspx?stage=100&articleid=154253&submissionid=154918 2/3< BackGiemsa staining. The right lungs were processed for electron and light microscopy analysis as well as immunohistochemistry (IC) and Alcian Blue (AB)PAS staining. Moreover, to further investigate the changes primed by LPSneonatal instillation in the bronchiolar epithelium, a group of animals (n=6) (equally exposed to PBS or LPS) were sacrificed at 20 days of live and epithelialbronchiolar samples were obtained (20/animal) by lasser dissection microscopy. RNA extractions followed by qRTPCR were conducted in these samples. RESULTS Ultrastructural analysis demonstrated in LPSn/OVA the preservation in the normal phenotype of CC as well as a meaningful reduction (p