The innate immune response to Aspergillus fumigatus
Author:
Balloy V, Chignard M
Date: 11 August 2009
Abstract:
Despite the development of new treatments, the mortality due to invasive pulmonary aspergillosis remains above 50%, reaching 95% in certain situations. The battle against Aspergillus fumigatus involves several components of the pulmonary innate immune system: cells, mediators, and natural antifungal molecules involved in the recognition and elimination of the fungus, thereby preventing colonization of the respiratory system. With the 10,000-15,000l of air we inhale each day, the lungs are constantly exposed to a wide range of microorganisms, such as A. fumigatus. This fungus is ubiquitous in the environment and can release large numbers of spores able, due to their small size, to penetrate the respiratory tract. The spores of A. fumigatus, like those of any other pathogen, are then confronted with the innate immune system-a constitutive defense system that is permanently active and tightly regulated. The various elements of the pulmonary innate immune system-physical and cellular barriers and soluble mediators-are involved in the recognition and elimination of pathogens, thereby preventing colonization of the respiratory system. Consequently, the presence of spores in immunocompetent hosts is completely innocuous, because these spores are normally eliminated. However, changes in one of the components of the defense system may lead to the development of pulmonary infections. Thus, in immunocompromised individuals, the spores are able to develop and cause pulmonary mycoses. These mycoses, known as aspergillosis, are highly variable, with the range of presentations extending from an allergy-type illness, allergic bronchopulmonary aspergilloses, to a very serious generalized and frequently fatal infection: invasive pulmonary aspergillosis (IPA). Despite the development of new treatments, the mortality of IPA remains above 50%, reaching 95% in certain situations. Immunosuppression, whether due to drug treatment or secondary to an underlying disease, plays a key role in the occurrence of IPA. Patients suffering from hematological disorders and patients who have undergone transplantation are therefore at a particularly high risk of IPA.
Download the full article (Disclaimer)
This manuscript library of ~16,000 articles (1729-2024) related to Aspergillus and aspergillosis is intended for individual study only, and is provided as contribution to global understanding of the topic. Please refer to the publisher’s guidance about any other usage.