Pneumocystis pneumonia: pitfalls and hindrances to establish a reliable animal model

International audience ; Pneumocystis pneumonia is a severe lung infection that occurs primarily in largely immunocompromised patients. Few treatment options exist and the mortality remains substantial. To develop new strategies in the fields of diagnosis and treatment, it appears critical to improve the scientific knowledge about the biology of the Pneumocystis agent and the course of the disease. In the absence of in vitro continuous culture system, in vivo animal studies represent a crucial cornerstone for addressing Pneumocystis pneumonia in laboratories. These models constitute an essential complement to clinical studies. Here, we provide an overview of the animal models of Pneumocystis pneumonia that were reported in the literature over the last 60 years. It summarizes the various technical parameters to consider in the preparation of the model and the interpretation of the limits / results of such studies. Overall, this review highlights the great heterogeneity of the variables studied: the choice of the host species and its genetics, the different immunosuppressive regimens to render animal susceptible, the experimental challenge, and the different validation methods of the model.