Characterization of human dialyzable transfer factor from normal and chronic lymphoid leukemia sources

Dialysates of lymphomonocytes can be roughly quantified through the use of optical density and measurements of RNA and protein contents. Dialysates of normal lymphocytes (N-TFd) contain about 224 +/- 67 mug of RNA-like material per 10(8) cells, 75 to 90% of which is eluted in fractions II and III on Biogel P10 chromatography. In contrast, dialysates of lymphocytes from patients suffering chronic lymphoid leukemia (CLL-TFd) contain approximately 12 times less RNA-like material (about 27 +/- 11 mug per 10(8) lymphocytes) and have a different characteristic chromatographic pattern. Bioassays with crude dialysates confirm (a) that N-TFd increases 3H-thymidine incorporation by nonsenstitized lymphocytes "in vitro" in the presence of PPD, and (b) that inbred Lewis rats develop positive skin tests (systemic transfer) after receiving injections of N-TFd or of fractions II and III from Biogel fractionation of N-TFd. Neither test gives positive results when CLL-TFd is used.