CSF2 and inborn error of immunity: In addition, diseases due to aAbs targeting specific cytokines or cytokine pathways, which are classified in a unique category termed “phenocopies of primary immunodeficiency”, comprise acquired immunodeficiency characterized by the presence of some anti-cytokine aAbs, notably to IFN-γ, interleukin (IL)-6, IL-17, IL-22, and granulocyte macrophage colony stimulating factor (GM-CSF).