Demonstration of α2-macroglobulin in cultured fibroblasts, using crossed immunoelectrophoresis

Normal human fibroblasts, cultured in medium supplemented with newborn calf serum (NCS), were examined using crossed immunoelectrophoresis, with antibodies directed against NCS. About ten serum components were detected in cell sonicates. The procedure by which the cells were dissociated (EDTA or trypsin) did not affect the number of peaks observed. The most prominent serum component present in cell sonicates was identified as α₂-macroglobulin.