Innate immunity to filarial infections: the innate lymphoid cells as the new actors in the scene?

Innate immunity to filarial infections: the innate lymphoid cells as the new actors in the scene ?

Lymphatic filariasis and onchocerciasis are major neglected tropical diseases affecting over 140 million people worldwide with painful and profoundly disfiguring pathologies such as lymphedema. Despite crucial roles of granulocytes in controlling the early stages of the infection, little is known about the induction of the innate immune response at the infection site. As innate lymphoid cells (ILCs) are known to play important roles in the initiation of the inflammation, we therefore investigated comparative ILC1, ILC2 and natural killer (NK) cell population expansion during filarial infections with Brugia malayi and Onchocerca ochengi. Using a range of immunocompetent and immunodeficient mice, we have shown that in NK-deficient mice an increased parasite susceptibility was linked to a significant eosinophil recruitment impairment, indicating a potential novel role for NK cells in regulating eosinophil granulocyte filaricidal activity. Those results are providing new insights on lymphatic filariasis innate immune response, which could lead to new approaches in anti-filarial drug development (e.g. in the development of our new in vivo models of filariasis for drug screening). Moreover, it has been shown in helminth-infected patients that eosinophils and alternatively activated macrophages  could protect from the development of metabolic diseases. One could therefore question the role of the ILCs in a such context.

Profile for Dr Nicolas Pionnier