Here, we used C5aR1fl/fl and LysM-C5aR1 KO mice in a model of OVA-driven experimental allergic asthma to assess the impact of conditional C5aR1 deletion inLysM-expressing cells on their recruitment to the airways and the lung tissue and the development of allergic asthma. The gene discussed is C5AR1; the disease is allergic asthma.