Age influence on mice lung tissue response to Aspergillus fumigatus chronic exposure
Marta Kinga Lemieszek1, Jacek Dutkiewicz1, Marcin Golec1
1Institute of Agricultural Medicine, Lublin, Poland.
Introduction And Objective:
Exposure to conidia of Aspergillus fumigatus was described as a causative factor of a number of the respiratory system diseases, including asthma, chronic eosinophilic pneumonia, hypersensitivity pneumonitis and bronchopulmonary aspergillosis. The study investigates the effects of the repeated exposure to A. fumigatus in mice pulmonary compartment. Our work tackles two, so far insufficiently addressed, important aspects of interaction between affected organism and A. fumigatus: 1) recurrent character of exposure (characteristic for pathomechanism of the abovementioned disease states) and 2) impact of aging, potentially important for the differentiation response to an antigen.
Materials And Methods:
In order to dissect alterations of the immune system involved with both aging and chronic exposure to A. fumigatus, we used 3- and 18-month-old C57BL/6J mice exposed to repeated A. fumigatus inhalations for 7 and 28 days. Changes in lung tissue were monitored by histological and biochemical evaluation. Concentration of pro- and anti-inflammatory cytokines in lung homogenates was assessed by ELISA tests.
Results And Conclusions:
Our study demonstrated that chronic inflammation in pulmonary compartment, characterized by the significant increase of proinflammatory cytokines (IL1, IL6, IL10) levels, was the dominant feature of mice response to repeated A. fumigatus inhalations. The pattern of cytokines' profile in the course of exposure was similar in both age groups, however in old mice the growth of the cytokines' levels was more pronounced (especially in case of IL1).
Insights
Repeated Aspergillus fumigatus inhalation causes chronic lung inflammation, with higher cytokine levels in older mice. This study highlights aging
Area of Science:
- Immunology
- Pulmonology
- Aging Research
Background:
- Aspergillus fumigatus conidia exposure is linked to respiratory diseases like asthma and hypersensitivity pneumonitis.
- The impact of recurrent exposure and aging on immune responses to A. fumigatus is not fully understood.
Purpose of the Study:
- To investigate the effects of repeated A. fumigatus exposure on the pulmonary immune system in mice.
- To assess the influence of aging on the host's response to chronic A. fumigatus inhalation.
Main Methods:
- 3- and 18-month-old C57BL/6J mice were exposed to A. fumigatus inhalations for 7 and 28 days.
- Lung tissue was analyzed using histological and biochemical methods.
- Pro- and anti-inflammatory cytokine concentrations (IL-1, IL-6, IL-10) were measured via ELISA.
Main Results:
- Chronic pulmonary inflammation was observed, marked by increased pro-inflammatory cytokine levels (IL-1, IL-6, IL-10).
- Cytokine profiles were similar across age groups during exposure.
- Older mice exhibited a more pronounced increase in cytokine levels, particularly IL-1.
Conclusions:
- Repeated A. fumigatus exposure induces significant chronic inflammation in the lungs.
- Aging exacerbates the inflammatory response to A. fumigatus, leading to higher cytokine concentrations.
