Figure 4.

In vitro cell binding and specificity of MF-anti-CEA by ELISA. (A) Detection of CEA expressed in human colorectal cancer cells. LS174T and HCT116 cells were assessed by ELISA with anti-CEA at two different concentrations as primary antibody; (B) LS174T cells’ binding efficacy of MF-anti-CEA. ELISA was performed with either MF-anti-CEA or supernatants from antibody conjugation process as primary antibody; (C) MF-anti-CEA specificity for CEA was assessed in LS174T and HCT116 cells by ELISA with MF-anti-CEA as primary antibody. In figures (B and C) PBS and MF were utilized as negative controls and free anti-CEA antibody as positive control.

Note: Different letters mean statistical difference (P < 0.05).

Abbreviations: MF, magnetic fluid; CEA, carcinoembryonic antigen; ELISA, enzyme-linked immunosorbent assay; PBS, phosphate buffered saline.