T follicular helper cells (Tfh) specialize in providing cognate help to B cells and are
fundamentally required for the generation of T cell–dependent B cell responses. Perturbations
in the development and/or function of Tfh cells can manifest as immunopathologies,
such as immunodeficiency, autoimmunity, and malignancy. Unraveling the cellular and
molecular requirements underlying Tfh cell formation and maintenance will help to identify
molecules that could be targeted for the treatment of immunological diseases that are
characterized by insufficient or excessive Ab responses.