Mucoproteins of Human Plasma. IV. Electrophoretic Demonstration of Mucoproteins in Serum at pH 4.5.

Abstract
When serum is subjected to electrophoresis at pH 4.5, two components are seen which have isoelectric points more acid than those of albumin. One of these has been identified with a mucoprotein which has been shown to increase in amount in cancer, pneumonia, and certain other diseases. The second component, with a less acid isoelectric point, may also be a mucoprotein, but this point has not been definitely established.