For example, AAbs to interferon gamma (IFNγ), a key mediator of protective immune responses against intracellular organisms [4], have been found to be associated with chronic, disseminated, treatment refractory infections with intracellular organisms such as mycobacteria, while AAbs to GM-CSF (Granulocyte Macrophage Colony Stimulating Factor), are associated with PAP (Pulmonary Alveolar Proteinosis), since GM-CSF orchestrates the maturation and function of pulmonary alveolar macrophages [5,6]. Here, CSF2 is linked to infection.