Homozygous mice for the targeted mutation are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities.

To evaluate the function of MC-expressed FceRIα in PH development, MC-specific Fcer1a KO mice (Fcer1aMC−/−, MCKO) were generated by cross breeding Fcer1a^flox/flox mice (WT) mice with Mcpt5-Cre transgenic mice (Fig. 4d). Four weeks of hypoxia exposure resulted in PH in WT mice, indicated by increased RVSP and decreased PA AT/ET, which were improved in the MCKO mice (Fig. 4e,g). No significant changes were observed in RV hypertrophy, consistent with previous findings of cromolyn administration in the MCT model15 (Fig. 4f). Histological analyses showed decreased wall thickness and vascular muscularization in MCKO compared with WT mice under hypoxia (Fig. 4h–j). Together, these results suggested that FceRIα expressed in MCs contributed to the development of PH.(source: Shu, T et al.,2021)