Separation of folate binding protein from human serum by DEAE-cellulose column chromatography.

On diethylaminoethyl-cellulose column chromatography, the folate binding protein in the serum of 21 patients eluted in the early effluents as a single sharply defined peak. The chromatographic behavior of the folate binder remained unchanged whether or not the serum was, before chromatography, complexed with tritium-labeled pteroylglutamic acid ([3H]PGA), dialyzed, or charcoal-adsorbed. Heating to 100 degrees C for 10 min dissociated the [3H]PGA-binder complex while destroying the folate binding property. The presence or appearance of this folate binder in increased amounts in the serum of patients with various diseases may be related to conditions of increased tissue turnover.