The extraction and partial purification of transfer factor from human urine.

Abstract

The objectives of this study were: (1) to confirm that transfer factor (TF) (also known as dialyzable leukocyte extract) can be extracted from human urine; (2) to develop a more efficient method of extraction, and; (3) to determine the molecular weight of the TF in urine. The study used urine from donors with known skin test reactions to purified protein derivative of Seiberts (PPD-S) and coccidoidin immitis (cocci). For the first study, a forty-eight hour catch of urine and bovine leukocytes were divided into aliquots and processed using dual acetone precipitation followed by dialysis through a 6,000 molecular weight cut off membrane under negative pressure for 4 to 5 days to extract the TF-like substance. Results confirmed that TF activity could be derived from human urine, and that this procedure could be used with blood to extract TF. In the second study, tangential flow filtration combined with stirred cell final filtration and dual acetone precipitation required only 10 hours to produce TF activity nearly identical to the first study. The stirred cell and acetone procedure could also be used to extract TF from leukocyte extracts. Concentrated urine aliquots placed in equilibrium dialysis membranes demonstrated that the most active fraction was the 2,000 dialysate which was consequently subjected to Fast Atom Bombardment (FAB) ionization using a four sector mass spectrometer. This produced two groups of activity: one between 1270-1510, and the other between 1880-2142 daltons. In conclusion, TF can be extracted from human urine. Tangential flow filtration followed by stirred cell filtration can be used to extract the active substance, and the molecular weight of the active substance in urine TF is between 1279-1510 or 1880-2142 daltons.