Confirmation of CRP-SAA complexes in the serum samples or cell culture media and expression of SAA in lung cancer tissues. a Identification of CRP-SAA complexes in mixed serum from ten healthy controls and from ten lung cancer patients through co-immunoprecipitation (co-IP). b Identification of CRP-SAA complexes in serum samples from individual healthy controls and lung cancer patients through co-IP. c Identification of CRP-SAA complexes in culture media from mixed 293FT-CRP and 293FT-SAA cells through co-IP. d Immunohistochemical assay shows high expression of SAA in both lung adenocarcinoma and squamous cell carcinoma tissues and low expression in normal lung tissues. e Enzyme-linked immunosorbent assay (ELISA) for the detection of CRP-SAA and total SAA. f The standard curve of the ELISA system for CRP-SAA using serially diluted culture media from mixed 293FT-CRP and 293FT-SAA cells.