T follicular helper cells: Their development and importance in the context of helminthiasis.

The development of T follicular helper cells (Tfh) is a multifactorial process that occurs in multiple stages. After their activation the Tfh cells interact with the B cells to complete their differentiation. During this process, the Tfh cells begin to express canonical molecules such as the transcription factor B-cell lymphoma 6 protein, the CXC chemokine receptors type 5, and the inducible T-cell costimulator, as well as secreting other molecules such as IL-21. This whole process is regulated positively and negatively by several factors so that the best response is offered in the face of diseases of various origins, among them helminthiasis. In this context, the role of circulating Tfh, IL-4 and IgG subtypes is essential for an effective response against these pathogens. In this review, the migration process and the differentiation of Tfh, the regulation, their cell subtypes and the role of Tfh in the context of helminth infections will be addressed.