Dataset Information

Evolution of the Immune Response to Chronic Airway Colonization with Aspergillus fumigatus Hyphae.

ABSTRACT: Airway colonization by the mold Aspergillus fumigatus is common in patients with underlying lung disease and is associated with chronic airway inflammation. Studies probing the inflammatory response to colonization with A. fumigatus hyphae have been hampered by the lack of a model of chronic colonization in immunocompetent mice. By infecting mice intratracheally with conidia embedded in agar beads (Af beads), we have established an in vivo model to study the natural history of airway colonization with live A. fumigatus hyphae. Histopathological examination and galactomannan assay of lung homogenates demonstrated that hyphae exited beads and persisted in the lungs of mice up to 28 days postinfection without invasive disease. Fungal lesions within the airways were surrounded by a robust neutrophilic inflammatory reaction and peribronchial infiltration of lymphocytes. Whole-lung cytokine analysis from Af bead-infected mice revealed an increase in proinflammatory cytokines and chemokines early in infection. Evidence of a Th2 type response was observed only early in the course of colonization, including increased levels of interleukin-4 (IL-4), elevated IgE levels in serum, and a mild increase in airway responsiveness. Pulmonary T cell subset analysis during infection mirrored these results with an initial transient increase in IL-4-producing CD4(+) T cells, followed by a rise in IL-17 and Foxp3(+) cells by day 14. These results provide the first report of the evolution of the immune response to A. fumigatus hyphal colonization.

SUBMITTER: Urb M

PROVIDER: S-EPMC4534667 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Evolution of the Immune Response to Chronic Airway Colonization with Aspergillus fumigatus Hyphae.

Urb Mirjam M Snarr Brendan D BD Wojewodka Gabriella G Lehoux Mélanie M Lee Mark J MJ Ralph Benjamin B Divangahi Maziar M King Irah L IL McGovern Toby K TK Martin James G JG Fraser Richard R Radzioch Danuta D Sheppard Donald C DC

Infection and immunity 20150629 9

Airway colonization by the mold Aspergillus fumigatus is common in patients with underlying lung disease and is associated with chronic airway inflammation. Studies probing the inflammatory response to colonization with A. fumigatus hyphae have been hampered by the lack of a model of chronic colonization in immunocompetent mice. By infecting mice intratracheally with conidia embedded in agar beads (Af beads), we have established an in vivo model to study the natural history of airway colonizatio ...[more]

PMID: 26123803

Similar Datasets

Project description:BackgroundAspergillus fumigatus is the most common etiologic agent of invasive aspergillosis in immunocompromised patients. Several studies have addressed the mechanism involved in host defense but only few have investigated the pathogen's response to attack by the host cells. To our knowledge, this is the first study that investigates the genes differentially expressed in conidia vs hyphae of A. fumigatus in response to neutrophils from healthy donors as well as from those with chronic granulomatous disease (CGD) which are defective in the production of reactive oxygen species.Methodology/principal findingsTranscriptional profiles of conidia and hyphae exposed to neutrophils, either from normal donors or from CGD patients, were obtained by using the genome-wide microarray. Upon exposure to either normal or CGD neutrophils, 244 genes were up-regulated in conidia but not in hyphae. Several of these genes are involved in the degradation of fatty acids, peroxisome function and the glyoxylate cycle which suggests that conidia exposed to neutrophils reprogram their metabolism to adjust to the host environment. In addition, the mRNA levels of four genes encoding proteins putatively involved in iron/copper assimilation were found to be higher in conidia and hyphae exposed to normal neutrophils compared to those exposed to CGD neutrophils. Deletants in several of the differentially expressed genes showed phenotypes related to the proposed functions, i.e. deletants of genes involved in fatty acid catabolism showed defective growth on fatty acids and the deletants of iron/copper assimilation showed higher sensitivity to the oxidative agent menadione. None of these deletants, however, showed reduced resistance to neutrophil attack.ConclusionThis work reveals the complex response of the fungus to leukocytes, one of the major host factors involved in antifungal defense, and identifies fungal genes that may be involved in establishing or prolonging infections in humans.

Dataset Information

Evolution of the Immune Response to Chronic Airway Colonization with Aspergillus fumigatus Hyphae.

Publications

Evolution of the Immune Response to Chronic Airway Colonization with Aspergillus fumigatus Hyphae.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets