Abstract
Asthma is a complex disease of the airways primarily mediated by T helper 2 cells and innate lymphoid type 2 cells (Licona et al.,2013). Mice do not develop spontaneous asthma and therefore models have been developed for the assessment of key processes that underlie human pathology (Nial et al.,2008). Exposure to House Dust Mite (HDM) extract induces many key features of acute airway inflammation including elevated IgE levels, eosinophilia, goblet cell metaplasia, epithelial hypertrophy and airway hyperresponsiveness (AHR) in response to methacholine (Hammad et al., 2009; Dullaers et al., 2012; Coquet et al., 2015). The exact dose and duration of exposure to HDM can affect the type and extent of inflammation. In our case, we start with a low sensitizing dose that is increased on challenge, while others use differing schedules or a higher antigen concentration during sensitization of mice (Hondowicz et al., 2016; Trompette et al., 2014; Zaiss et al., 2015). We believe that using a low sensitizing dose more accurately separates the primary and secondary immune responses and reduces the possibility that HDM given during sensitization continues to fuel the immune response during challenge (Coquet et al., 2015; Plantinga et al., 2013). Here, we outline in text, pictures and video how to administer HDM extracts or cytokines via the intranasal route and briefly touch upon the subsequent analysis of inflammation in the airways [covered otherwise in ( Han et al., 2013)].
Keywords: HDM, IL-33, Asthma, Lavage, Airway Inflammation
Materials and Reagents
Equipment
Procedure
Note: All experiments using mice should be approved by the relevant animal ethics committee in accordance with both national and international guidelines.
Representative data
Figure 6. Flow cytometry plots of cells isolated from BAL. BAL cells from C57Bl/6 mice were collected 4 days after the last HDM challenge. Representative FSC-A/SSC-A profiles from mice exposed to HDM or a naïve control are shown in A (HDM-exposed) and B (Naïve). The presence of eosinophils in the BAL can be defined as Siglec-F+CD11c- cells and alveolar macrophages as Siglec-F+CD11c+. The difference between inflamed BAL and naïve control is evident by the increased proportion of eosinophils (typically values range from 60-90%) in the former A and their almost complete absence in the latter B.
Notes
Acknowledgments
The authors acknowledge the services of the MTC animal facility (Karolinska Institute, Sweden). This work was supported by a Swedish Research Council Young Investigator Grant and a grant from the Swedish Cancer Society. This protocol was adapted from Coquet et al., 2015.
References
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Hi there. Typically we use a model whereby we sensitise with 1ug and challenge with 10ug. 100ug is quite a high dose, which is certainly used by other groups, but not usually by us. You can always titrate the amounts of hdm you use and this can be very important depending on the questions you want to answer. Good luck, j