Human transfer factor activity in the guinea pig: absence of antigen specificity

Effect of leukocyte and other tissue dialysates on NBT reduction and prostaglandin production in mice

The effects of human leukocyte, porcine spleen and bovine liver dialysate fractions on Listeria resistance were measured by survival studies and by assessing the capacity of peritoneal macrophages to produce superoxide anion (0-2) and prostaglandins. Leukocyte (DLE) and other tissue dialysates were fractionated on a Sephadex G-10 column. Thereafter the significant activities were found in fraction III of DLE, fraction II of porcine spleen and fraction II + III of bovine liver dialysate. The treatment with active porcine spleen dialysate fraction increased the capacity of peritoneal macrophages to generate superoxide anion. On the other hand, this fraction significantly decreased the production of prostaglandin PGE2 and thromboxan B2. These results may indicate that all dialysates can be a source of a non-specifically-acting immunomodulatory preparation and that the infection-resistance-increasing substances seem to operate via the monocyte/macrophage activation.

Dialysable leukocyte extracts (transfer factor) augment nonspecifically keyhole limpet haemocyanin and horseshoe crab haemocyanin skin reactivity in unimmunized human recipients

Dialysable leukocyte extracts (DLE) may induce marked changes in the immune expression of human recipients. It is unclear whether the conversion of skin reactivity by DLE is due to a donor-related specific transfer factor or to an antigen nonspecific augmenting factor which enhances a preexisting low-level response in DLE recipients. In this study, DLE from immunized and unimmunized human and calf donors or saline was administered to 88 medical students. The recipient population demonstrated minimal background responses to the test antigens keyhole limpet haemocyanin (KLH) and horseshoe crab haemocyanin (HCH). The results indicate that the DLE preparations from both immunized and unimmunized donors significantly stimulated skin reactivity but not in vitro responses to both KLH and HCH in the recipient population. The results suggest that these DLE preparations contain an immunologically nonspecific augmentor, which stimulates a preexisting low-level response in the unimmunized population to become a clearly observable skin reaction.

Effect of human leukocyte and other tissue dialysates on Listeria resistance and phagocytosis in mice

The effect of dialyzable transfer factor (TFd) on Listeria resistance was measured by survival studies and by assessing phagocytic capacity of peritoneal macrophages. Unfractionated dialysates from human leukocytes (DLE), bovine liver, porcine spleen and kidney as well as saline were injected i.p. into NMRI mice 72 h before the i.p. injection of 1-3 x 10(6) Listeria organisms. The results show that DLE, porcine spleen and bovine liver dialysate increased the LD50 5-20 times. Porcine kidney dialysate had no effect on the survival of the mice. After the fractionation of porcine spleen dialysate on Sephadex G-10 column, a significant activity was found in two fractions, II and IX. When active fractions were given together (II + IX) i.p. three days prior to the infection with listeria organisms, the survival of mice increased significantly, whereas no effect was seen when the fractions were given i.v. and the bacteria i.p. Also the treatment with active fractions increased significantly the phagocytic capacity of peritoneal macrophages. Taken together, our results suggest that the Listeria protective substances seem to operate via monocyte activation.

Augmentation of delayed-type hypersensitivity in antigen-primed guinea pigs by human dialyzable leukocyte extract. Chromatographic and enzymatic characterization of the active principle

Column chromatographic purification and sensitivity towards enzymatic treatments of dialyzable transfer factor (TFd), the immunologically specific component of dialyzable leukocyte extract (DLE), have previously been used in its biochemical characterisation. In the present work we studied the effect of enzymes and the Sephadex G-10 chromatographic separation of the components of DLE augmenting delayed-type hypersensitivity. Skin reactivities to streptokinase-streptodornase (SK-SD) and tuberculin PPD were significantly augmented by injecting DLE into antigen-primed guinea pigs. The augmentation caused by DLE treatment correlated to the pre-existing level of immunity in the recipients. Most of the augmentory activity resided in 2 adjacent fractions, eluting early from a Sephadex G-10 column. This augmentation was destroyed by alkaline hydrolysis, by treatment with pronase, proteinase K, ribonuclease, and nuclease P1, but not by alkaline phosphatase or phosphodiesterase II. The observed sensitivities towards these enzymes, except that for ribonuclease, were closely similar to those described for the specific TFd component of DLE. These results are compatible with the idea that either the nonspecific augmenting and the specific TFd molecules are principally similar, or that the TFd molecules, in addition to their capacity to transfer specific immunity, also have an augmenting effect, which needs in its manifestation a sub-threshold dose of immunogen.

Immunomodulation in guinea pigs by porcine spleen cell dialysate

The effect of porcine spleen dialysate was studied on delayed-type hypersensitivity reactions, as well as on the phagocytic capacity and intracellular prostaglandin levels of peritoneal macrophages. Porcine spleen cell dialysate was fractionated on Sephadex G-10 and these fractions, as well as unfractionated dialysate, were injected intraperitoneally into antigen-primed guinea pigs. The guinea pigs were tested for delayed-type hypersensitivity towards PPD and SK-SD. The results show that unfractionated spleen cell dialysate augmented slightly the delayed-type hypersensitivity reactions, and after fractionation a significant augmentory activity was detected in two adjacent, early eluting fractions. This active elution region corresponds to the elution region where most of the guinea pig DTH augmenting activity of leukocyte dialysate is also detected. Furthermore, these fractions significantly augmented the phagocytic capacity of peritoneal macrophages, and decreased the intracellular levels of prostaglandin PGE2, thromboxan B2 and prostacyclin. These results indicate that porcine spleen cells from non-immunized animals can be used as a source for a non-specifically acting immunomodulatory preparation, which resembles that found in human leukocyte dialysate. These immunomodulatory substance(s) seem to operate via monocyte activation.

Investigations of transfer factor activity in resistance to Trichostrongylus colubriformis infections in guinea-pigs

Resistance to challenge infection with Trichostrongylus colubriformis was studied in an outbred strain of guinea-pigs. Resistance was conferred by previous infections of 50 or 100 infective larvae and by intraperitoneal, intramuscular and subcutaneous administration of dialysed transfer factor prepared from guniea-pigs infected with T. colubriformis, by intraperitoneal administration of transfer factor prepared from the blood of sheep infected with T. colubriformis and on one of three occasions using transfer factor prepared from guinea-pigs which had not been infected with T. colubriformis. No significant resistance was transferred by administration of antigen prepared from adult T. colubriformis, or by non-dialysed transfer factor, or by dialysed transfer factor prepared from T. colubriformis-infected guinea-pig tissue which had been stored for several months at - 20 degrees C.

Transfer factor

The understanding of passive transfer of cell mediated-immune responses with transfer factor and other cell free materials has progressed to the point that investigators are seeking the chemical identity of the molecule(s) that are responsible for these effects and are working on their mechanisms of action. In addition, clinical trials are underway that should clarify the potential for use of transfer factor in treatment of infections, neoplastic and autoimmune diseases. This chapter will critically review the past and current data concerning the components of transfer factor and their effects on immunologic and inflammatory reactions. Some of the recently developed animal models will be described and evaluated, and the clinical studies that have provided conclusive data regarding efficacy will be reviewed.

Studies on the chemical nature of dialysable transfer factor. Comparison of human leukocyte dialysate and dialysates derived from human serum and from mammalian lymphoid and non-lymphoid organs

The chemical nature of human dialysable transfer factor (TFd), capable of augmenting delayed hypersensitivity (DH) in human recipients, and some mammalian organ dialysates, known to augment DH in antigen-primed guinea pigs, were compared using chromatography on Sephadex G-10 and G-25 columns and on thin-layer plates. The fractions of human leukocyte dialysate which eluted at or after the Vt of the Sephadex columns have previously been shown to contain the in vivo TFd-activity and therefore special attention was paid to corresponding dialysate fractions. All together 52 identified or unidentified components were found at or close to this elution region with thin-layer chromatography (TLC). The 14 identified substances were nucleobases, nucleosides, sugars and aromatic or heterocyclic amino acids. Unidentified components had similar staining characteristics as the identified ones on TLC. No evidence was found for the presence of peptides or nucleotides. There were no components specific for human leukocyte dialysate. Several of the identified and unidentified substances in fractions of humal dialysable leukocyte extract were common to all or nearly all dialysates. The possibility that some of the unidentified components might be responsible for the in vivo effect of human leukocyte dialysate in man or guinea pig is discussed.