CSF2 and pulmonary alveolar proteinosis: In an analysis of anti-GM-CSF AAbs isolated from patients with Pulmonary Alveolar Proteinosis (PAP), Piccoli and colleagues showed that while monoclonal anti-Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) AAbs showed diminished capacity to neutralize the cytokine in a bioassay, combinations of three non-competing anti-GM-CSF AAbs were effective in neutralizing the biological activity of GM-CSF.