As shown in Table 5, the most frequently cited article was published by Bruce C Trapnell in NEJM in 2003 (15), which reports that GM-CSF autoantibodies are markedly elevated in autoimmune PAP but not in patients with secondary PAP, congenital PAP, other lung diseases, or healthy people. This evidence concerns the gene CSF2 and autoimmune pulmonary alveolar proteinosis.