Sex-dependent Influence of LMAN1 on Allergen-induced Airway Hyperresponsiveness
Allergic asthma is a chronic inflammatory disease of the airways characterized by a type 2-high adaptive immune response towards common aeroantigens such as dust mite, pollen and animal dander. Despite the advances made towards translation of various biologics into the clinic, the limited efficacy of these therapies in certain populations, combined with the ineligibility of some patients for treatment (clinically or economically), have led to the continued need for the development of more widely effective allergic asthma therapies. Our lab previously identified lectin mannose-binding 1 (LMAN1) as a novel receptor for house dust mite (HDM) and showed that in vitro, LMAN1 downregulated inflammatory NF-?B signaling in DCs in response to HDM. In this follow-up work, we investigated the in vivo relevance of LMAN1 by subjecting LMAN1 knockout (KO) mice and wild type (WT) littermate controls to a model of HDM-induced allergic asthma. Surprisingly, we discovered that loss of LMAN1 led to opposing effects on airway hyperresponsiveness (AHR) which were dependent on the sex of the mice.  HDM-treated female LMAN1 KO mice showed increased AHR, while HDM-treated male KO mice showed decreased AHR, compared with their WT counterparts. We further identified the features of HDM-induced asthma which may account for the gender-biased effects of LMAN1 on lung function. This work not only highlights the complexity of the loss of LMAN1 in vivo but also suggests that such sex-dependent responses should be taken into consideration when pursuing LMAN1 as a therapeutic target for treatment of allergic asthma. Overall design: Primary murine tracheal epithelial cell cultures (MTECs) were established from WT and LMAN1 KO mice of both sexes. Cultures were left untreated or treated with HDM overnight, prior to extraction of RNA for RNA sequencing.