Preliminary studies on human "transfer factor" activity in guinea pigs. Systemic transfer of cutaneous delayed-type hypersensitivity to PPD and SKSD

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.

An animal model for evaluation of antigen-specific dialyzable leukocyte extracts therapy of osteosarcoma

The effects of human osteosarcoma (OS)-specific dialyzable leukocyte extracts (DLE) in hamsters bearing human OS were investigated. The DLE used in this investigation was prepared from rabbits immunized with human osteosarcoma-associated antigens (DLE-OSAA). Tuberculin (DLE-PPD) and control DLE were prepared from rabbits injected with tuberculin or 0.85% NaCl (DLE-NaCl). DLE was administered subcutaneously into inbred hamsters (each injection contained DLE derived from 10(7) rabbit leukocytes). Four groups of animals were studied: group 1, amputation alone; group 2, amputation plus DLE-OSAA; group 3, amputation plus DLE-PPD; group 4, amputation plus DLE-NaCl. Of the DLE-OSAA-treated animals (group 2), 60% were still alive at 300 days postamputation; whereas in animals in groups 1, 3, and 4, all died within 90 days postamputation. In separate experiments, we found that 100% of the animals in groups 1, 3, and 4 developed pulmonary metastases within 30-60 days postamputation, whereas only 20% of the animals in group 2 developed metastases at the same time; indeed 40% of the DLE-OSAA-treated animals were free of metastases in 240-300 days postamputation. Both the leukocyte adherence inhibition assay (LAI) and lymphocyte DNA synthesis assay (LDS) were used to monitor the transfer of antigen-specific cell-mediated immunity in each group of tumor-bearing hamsters. All surviving hamsters in group 2 had high LAI and LDS activity. Our results suggest that DLE-OSAA is effective in preventing pulmonary metastases and death of OS-bearing hamsters (after amputation) as compared with amputation alone, amputation plus DLE-NaCl, and amputation plus DLE-PPD, and that its effect is via an antigen-specific mechanism.

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.

Transfer of osteosarcoma-specific cell-mediated immunity in hamsters by rabbit dialyzable leukocyte extracts

We have investigated the transfer of specific cell-mediated immunity (CMI) to osteosarcoma-associated antigens (OSAA) to hamsters with dialyzable leukocyte extracts (DLE) from OSAA-immunized rabbits. The transfer of specific CMI was determined by leukocyte adherence inhibition (LAI) assay and skin testing. DLE was prepared from rabbits immunized with OSAA, purified protein derivative (PPD), or fibrosarcoma cell plasma membrane preparation (FSM). Control DLE was prepared from rabbits injected with 0.85% NaCl. Significant leukocyte adherence inhibition was observed with leukocytes from hamsters that had received OSAA-specific, PPD-specific, and FSM-specific rabbit DLE, when OSAA, PPD, and FSM were used as antigens, respectively. Similarly, significant ear swelling after injection of OSAA, PPD, or FSM was observed only in hamsters that had received DLE from rabbits immunized with OSAA, PPD, or FSM, respectively. These results suggest that CMI specific for OSAA, PPD, or FSM can be transferred to normal hamsters by DLE from immunized rabbits.

Specific mediation of cellular immunity to Toxoplasma gondii in somatic cells of mice

Lymphocytes from mice immunized against Toxoplasma gondii protected T. gondii-infected macrophage and kidney cell cultures. After contact with antigens, supernatants of such immune lymphocytes, also contained a factor protective for T. gondii-infected macrophages and kidney cells. Supernatants were protective only when the lymphocytes and kidneys cells were isogeneic. Protection was specific in that supernatants from only T. gondii-immune, but not Besnoitia jellisoni-immune, lymphocytes provided protection against toxoplasmosis. Sixteen to 24 h were required for an appreciable amount of protective factor to be secreted; a similar absorption time was necessary for kidney cells to be protected. Peritoneal lymphocyte lysates, prepared as transfer factor, contained protective substances with a potency similar to that of lymphocyte supernatants, which were also strain restricted in their effect.

Cell-mediated immunity: correlation of mixed-leucocyte-macrophage migration inhibition with delayed-type hypersensitivity after immunization and donor-specific transfer of cell migration inhibition by dialyzable leucocyte extract

Active and adoptive sensitization of rhesus monkeys (Macacca mulatta) as well as the development of a novel sensitive in vitro cell migration inhibition assay for cell-mediated immunity (CMI) in this species are described. First, the correlation of mixed leucocyte-macrophage migration tests (LMMI) with the whole blood lymphocyte transformation (LT) and the delayed hypersensitivity skin test (DH) in immunized animals are shown. Second, these tests are used to demonstrate adoptive transfer of specific/nonspecific cellular immunity (CMI) with dialyzable leucocyte extract (DLE) from immunized donor to unimmunized recipient monkeys. Seventeen animals were immunized with keyhole limpet haemocyanin (KLH) or hepatitis B surface antigen (HBsAg) in Freund's complete adjuvant (FCA) or with FCA alone. Acquisition of antigen-specific cell-mediated immunity was detected by all three tests within 5 weeks of immunization. Positive LMMI responses were associated with positive DH and LT. However, there was no correlation between the magnitude or time of development of the three responses. Therefore, the LMMI test, like the LT test, is an in vitro parameter of DH, but reflects the activity of different subpopulations of lymphocytes and is regulated by different mechanisms. In addition, 12 naive animals received DLE. Within 3 weeks, transfer of sensitivity was detected towards antigens to which the recipients had previously not been reactive but the donors had been. An enhancement of transformation response to phytohaemagglutinin was also seen. Thus, rhesus DLE contains both donor-specific transfer factor-like and nonspecific adjuvant-like activities. In DLE recipients, unlike immunized animals, LMMI responses were dissociated from DH or LT responses in that positive LMMI was mostly seen with negative DH or LT to antigens. Therefore, LMMI emerged as the most sensitive assay for detecting adoptive transfer of CMI by DLE in vivo, supporting the view that different mechanisms regulate LMMI, LT, and DH.

In vivo effects of human dialyzable leukocyte lysate. III. Modulation of the spleen cell proliferative response to antigen by components of leukocyte dialysates and an initial characterization of an ampliative nucleoside

The augmentative effects of isolated components of human dialyzable leukocyte lysates upon the proliferative response to antigen were investigated. Sequential Sephadex G-25 and Bio-Gel P-4 chromatography separated five distinct fractions which, 24 hr after injection into Keyhole limpet hemacyanin (KLH)-sensitive mice, either augmented or suppressed the in vitro spleen cell proliferative response to KLH. An amplifier molecule was isolated from one of the augmentative fractions by high-pressure, reverse-phase liquid chromatography. Preliminary structural analysis of the amplifier component indicated a nucleoside structure, similar to--but possibly distinct from--thymidine.

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.

Transfer factor and possible applications in gynecology

Dialyzable transfer factor (TFd) is reviewed against its historical background, preparation methods, physiochemical properties, possible mechanisms of action, pharmacology, and clinical studies, including several areas relating to gynecology. The possible role of TFd as an adjunct in the treatment of cancer is discussed. The discussion centers on gynecologic cancer in several patients who have received TFd. The difficulties and future possibilities for this modality of treatment are considered.

Immunotherapy of viral infections with transfer factor

It has been reported that dialysable leucocyte extract preparations, thought to contain transfer factor, may be used therapeutically for the treatment of a variety of immunodeficiency syndromes. Clinical and laboratory studies have suggested that such preparations, in addition to transferring specific cellular immunity may also contain non-specific adjuvant activities. Attempts at immunotherapy of viral infections are described against a background of current research on the biological and biochemical properties of leucocyte dialysates.