Basophils Amplify Type 2 Immune Responses, but Do Not Serve a Protective Role, during Chronic Infection of Mice with the Filarial Nematode Litomosoides sigmodontis

Abstract

Material

Type 2 Innate Immunity in Helminth Infection Is Induced Redundantly and Acts Autonomously following CD11c+Cell Depletion

“…Likewise, in transgenic constructs of basophil-specific lineage ablation, normal Th2 responsiveness to N. brasiliensis is observed (39,60). Nonetheless, basophils can significantly enhance Th2 immunity in settings such as infected tissue (64) and can promote rapid primary (60) and secondary (41) Th2 immunity to N. brasiliensis.…”

The Use of Filariae as a Therapeutic Agent for Hypersensitivity Diseases

“…The reduction in allergen-specific and autoantibody levels is an interesting phenomenon, as other groups have reported similar results when infection is given prior to sensitization (17; 47; 180). In contrast to reductions in antibodies specific to environmental or self-antigens, levels of L. sigmodontis-specific and non-specific antibodies rise throughout the course of infection (223). Indeed, our ELISA and ELISPOT data (Fig.…”

“…Basophil activity rises steadily 37 throughout acute infection and activation peaks at week 8 when MF are first detected in the blood (223). At week 10, there is a simultaneous decrease in basophil activation and increase in MF production (223). Thus, parasite-induced immune regulation appears to peak at 10 weeks post-infection.…”

“…L. sigmodontis antigen (LsAg)-specific IgE starts being produced at week 6 when Th2 cytokines IL-4 and IL-5 reach peak levels. Basophil activity rises steadily 37 throughout acute infection and activation peaks at week 8 when MF are first detected in the blood (223). At week 10, there is a simultaneous decrease in basophil activation and increase in MF production (223).…”

Immunology of Lymphatic Filariasis

“…In murine filarial infections, effector mechanisms involve multiple innate immune cells, with antibodies acting as initiators of immunity by activating Fc receptor expressing cells. Basophils, by their ability to produce high levels of IL-4, act as effectors to promote filarial killing in secondary or challenge infections (35). Although eosinophils are crucial contributors to the early IL-4 pool, they are also important in protection against primary filarial infections (36, 37).…”