Two Dimensional Electrophoresis Gel image of crude and depleted umbilical cord serum samples. For each gel, 150 μg of protein was separated over pH range 4-7 (24 cm strips) and 12.5% SDS-polyacrylamide gel. The gel was visualized by silver staining. The Immunoaffinity Albumin and IgG Depletion Kit (PROTIA, Sigma-Aldrich, Saint Louis, MO, USA) Kit was used to deplete albumin and IgG in the umbilical cord serum. Removal of these proteins improved the resolution in the albumin and IgG areas on the gel and increased the intensity of low abundance proteins. A) Two Dimension Electrophoresis Gel image of crude umbilical cord serum. B) Two Dimension Electrophoresis Gel image of depleted umbilical cord serum by Immunoaffinity Albumin and IgG Depletion Kit (PROTIA, Sigma-Aldrich, Saint Louis, MO, USA). Circles: regions of gel containing albumin, heavy and light chain of IgG before (panel A) and after depletion (panel B). Rectangle: used to highlight different protein patterns in the two groups, indicating a large number of protein spots that emerged in the depleted gel.