Developmental Change in Microheterogeneity of Serum Transferrin of Chickens

Developmental change in microheterogeneity of chicken serum transferrin (Tf) was investigated by polyacrylsmide-gel isoelectric focusing, direct immunofixation, and densitometry. Three main Tf species (Tf-0, Tf-1, and Tf-2, which have 0, 1, and 2 sialic acid residues per molecule, respectively) were resolved and their relative ratios were determined. As development proceeded, a relative increase occurred in the most acidic species (Tf-2) with decreases in the less acidic ones (Tf-0 and Tf-1).