Basophils Are Dispensable for the Control of a Filarial Infection

Abstract

Basophils are innate effector cells that contribute to allergic reactions and provide protection against parasites. Using basophil-deficient Mcpt8-cre mice, we have previously shown that these granulocytes contributed to the immune mediated early control of the gastrointestinal helminth Strongyloides ratti in mice. In this study, we analyze the impact of basophils on the immune response and defense against the tissue-dwelling filarial helminth parasite Litomosoides sigmodontis. Although basophils and IgE increased at the site of infection, the absence of basophils did not change the outcome of L. sigmodontis infection. Worm burden in the thoracic cavity and microfilaremiae in the peripheral blood were alike in L. sigmodontis–infected Mcpt8-cre mice compared with Mcpt8 wild type littermates during the entire course of infection. Analysis of the cytokine and Ab response to L. sigmodontis revealed no consistent alterations in the absence of basophils. Furthermore, basophil-deficient and -competent mice were protected to the same extent during a secondary infection with L. sigmodontis. In summary, our findings suggest that basophils are dispensable for the initiation of the appropriate immune response and host defense against L. sigmodontis infection in mice.