Dialyzable leukocyte extract therapy in immunodepressed patients with cutaneous leishmaniasis

Differential Activity of Human Leukocyte Extract on Systemic Immune Response and Cyst Growth in Mice with Echinococcus Multilocularis Infection After Oral, Subcutaneous and Intraperitoneal Routes of Administration

Alveolar echinococcosis (AE) caused by the larval stage of Echinococcus multilocularis is serious parasitic diseases associated with the host´s immunosuppression. The effects of human non-immune dialyzable leukocyte extract (DLE) on immune cells in blood and spleen and parasitic cysts weight in Balb/c mice after oral (PO), subcutaneous (SC) and intraperitoneal administration (IP) were compared. The reduction in cysts weight (p < 0.01) was recorded after PO route, whereas moderate reduction was found after SC and IP routes. The elevation of lymphoid populations in blood and spleen was found after PO administration (p < 0.01) in parallel with reduced myeloid population. Infection-elicited decline in B220+B cells was partially abolished by PO route, but DLE routes did not influence the CD3+ T cells. The proportions of CD3+CD4+Th lymphocytes were moderately upregulated, whereas CD3+CD8+Tc populations were reduced after all DLE routes (p < 0.01). PO administration increased CD11b+MHCII^high blood monocytes, CD11b-SigleF+ cell, but not CD11b+Si-glecF+ eosinophils in the blood, stimulated after SC and IP routes. DLE induced downregulation of NO production by LPS-stimulated adherent splenocytes ex vivo. Con A-triggered T lymphocyte proliferation was associated with the elevated IFN-γ production and transcription factor Tbet mRNA expression. The alleviation of Th2 (IL-4) and Treg (TGF-β) cytokine production by lymphocytes ex vivo paralleled with downregulation of gene transcription for cytokines, GATA and FoxP3. Reduction of myeloid cells with suppressive activity was found. The SC and IP routes affected partially the cysts weights, diminished significantly gene transcription, NO levels and Th2 and Treg cytokines production. Results showed that PO route of DLE administration was the most effective in ameliorating immunosuppression via stimulation of Th1 type, reducing Th2 and Treg type of immunity and CD3+CD8+Tc lymphocytes in the blood and spleens during E. multilocularis infection in mice.

Transfer Factor: Myths and Facts

Transfer factor (TF), also called "Lawrence transfer factor", or dialyzable leukocyte extract (DLE), has been used since the mid-twentieth century to transfer specific skin hypersensitivity through the injection of leukocytes from immunized donors to animals and humans. The main mechanism of action of TF has been suggested at the level of cell-mediated immunity, as it induces the production of migration inhibitory factor (MIF) and interferon gamma (IFN-γ). Otherwise, TF can inhibit nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB), and decrease tumoral necrosis factor α (TNF-α) and IL-4 levels. Given these biological effects, TF has been prescribed for a wide variety of conditions including infections, allergies, autoimmunity, and cancer, with inconsistent results. The exact nature of TF, however, remains unknown, so it has been impossible to accurately define its pharmacokinetics or dosage. This is further complicated because researchers have used TF in a variety of ways across the different studies: antigen-specific or non-antigen-specific, orally or subcutaneously administered, human and non-human origin. In this review we summarize the most important data about what TF is, its mechanism of action, how it is produced, its biological effects, and the available clinical trials using it, in order to establish its role and potential clinical applications in modern medicine.

Transfer Factor as an Option for Managing the COVID-19 Pandemic

Covid-19 or SARS-CoV-2, a new RNA virus with high infectivity, and seemingly low mutability, which appeared in 2019 in the Wuhan province of China, has created a pandemic with dire consequences. At the end of May 2020, it became the first cause of mortality. As no treatment or vaccine may become available before many months, and because occurrence of similar pandemics is only a matter of time, arguments are presented here for testing the effect of transfer factor (TF), an immunomodulator devoid of toxicity, which has been extensively studied in the past for the treatment and prevention of viral infections.

Histopathology of murine toxoplasmosis under treatment with dialyzable leukocyte extract

BACKGROUND

Dialyzable leukocyte extracts (DLEs) contain molecules smaller than 10 kDa with biological activity in receptor organisms. Primarily, they participate in the regulation of the Th1 immune response, which is essential for the control of several intracellular infections, such as toxoplasmosis. This disease is associated with congenital infection, encephalitis or systemic infections in immunocompromised individuals. The clinical course of this infection fundamentally depends on a well-regulated immune response and timely treatment with the appropriate drugs.

OBJECTIVE

The aim of this study was to evaluate the effect of treatment with a leukocyte extract, derived from crocodile lymphoid tissue, on the histopathology and brain parasite load in NIH mice that had been infected with cysts of Toxoplasma gondii (ME-49 strain).

METHODS

The treatment was applied during the acute and chronic stages of the infection. Histopathological changes were evaluated in the ileum, liver and spleen at one, four and eight weeks after infection and in the brain at week 8. The parasite load was evaluated by counting the cysts of T. gondii found in the brain.

FINDINGS

Compared to the control mouse group, the mice infected with T. gondii and under treatment with DLE showed less tissue damage, mainly at the intestinal, splenic and hepatic levels. In addition, a greater percentage of survival was observed, and there was a considerable reduction in the parasite load in the brain.

CONCLUSIONS

The results suggest that DLE derived from crocodile is a potential adjunctive therapy in the conventional treatment of toxoplasmosis.

Serum Derived Transfer Factor Stimulates the Innate Immune System to Improve Survival Traits in High Risk Pathogen Scenarios

Preclinical Research Transfer Factors (TFs) are low molecular weight (<5,000 daltons) biological response mediators. In the present study, a serum derived TF improved the ability of the recipient animal to survive high-risk infectious challenges (salmonellosis and canine parvoviral enteritis (CPV)) by altering the host's cytokine response profile. Mice mortally challenged with 5,000 colony-forming units of Salmonella experienced a group mortality of 73% while mice treated with a single 5 mg dose of the TF demonstrated a significant decrease in morbidity (7%, p ≤ 0.01). The splenic bacterial load in untreated mice was over 10,000 times higher than that in the TF treated mice. Twenty-four hours post-administration, the treated murine population expressed a rapid temporal increase in serum IL-6 (26-fold) and INF-γ (77-fold) concentrations. IL-6 can act as a critical signal regulating action against bacterial pathogens. A comparative double-blind study performed using dogs confirmed to be undergoing a canine parvovirus challenge showed that when conventional supportive therapy was supplemented with a single 5 mg TF dose there was a reduction (p ≤ 0.01) in group mortality (68% of the TF treated group survived versus 32% of the placebo group), an observation consistent with the observed increase in INF-γ, a cytokine associated with promoting antiviral activity. Drug Dev Res 78 : 189-195, 2017. © 2017 Wiley Periodicals, Inc.

Immodin and its immune system supportive role in paclitaxel therapy of 4T1 mouse breast cancer

It is evident that standard chemotherapy agents may have an impact on both tumor and host immune system. Paclitaxel (PTX), a very potent anticancer drug from a taxane family, has achieved prominence in clinical oncology for its efficacy against a wide range of tumors including breast cancer. However, significant toxicity, such as myelosuppression, limit the effectiveness of Paclitaxel-based treatment regimens. Immodin (IM) is low molecular dialysate fraction of homogenate made from human leukocytes. It contains a mixture of substances from which so far have been described e.g. Imreg 1 and Imreg 2 formed by the dipeptide tyrosine-glycine and the tripeptide tyrosine-glycine-glycine, respectively. The aim of this study was to explore immunopharmacological activities of IM, using the strongly immunogenic 4T1 mouse breast cancer model, and evaluate its effect on the reactivity and the efficiency of PTX cancer therapy. The results highlight a potentially beneficial role for IM in alleviating PTX-induced toxicity, especially on the nonspecific immunity, during breast cancer therapy. Co-treatment exhibited an antitumor effect including reduced tumor growth, prolonged survival of tumor bearing mice, increased number of monocytes and lymphocytes in peripheral blood. In spleens, IM+PTX therapy elevated proportion of whole lymphocytes in the account of myelo-monocytic cells characteristic with low expression of CD11c+ and bearing Fc receptor (CD16/32) as well as T-lymphocytes, NK cells and dendritic cells. Accumulation of tumor-associated granulocytes in stroma of PTX-treated group and intensive 4T1-necrosis/apoptosis in tumors after co-treatment were also recorded. These findings suggest the possibility of using IM alongside PTX treatment for maintaining the immune system functions and increasing patient survival.

Herpes murine model as a biological assay to test dialyzable leukocyte extracts activity

Human dialyzable leukocyte extracts (DLEs) are heterogeneous mixtures of low-molecular-weight peptides that are released on disruption of peripheral blood leukocytes from healthy donors. DLEs improve clinical responses in infections, allergies, cancer, and immunodeficiencies. Transferon is a human DLE that has been registered as a hemoderivate by Mexican health authorities and commercialized nationally. To develop an animal model that could be used routinely as a quality control assay for Transferon, we standardized and validated a murine model of cutaneous HSV-1 infection. Using this model, we evaluated the activity of 27 Transferon batches. All batches improved the survival of HSV-1-infected mice, wherein average survival rose from 20.9% in control mice to 59.6% in Transferon-treated mice. The activity of Transferon correlated with increased serum levels of IFN-γ and reduced IL-6 and TNF-α concentrations. Our results demonstrate that (i) this mouse model of cutaneous herpes can be used to examine the activity of DLEs, such as Transferon; (ii) the assay can be used as a routine test for batch release; (iii) Transferon is produced with high homogeneity between batches; (iv) Transferon does not have direct virucidal, cytoprotective, or antireplicative effects; and (v) the protective effect of Transferon in vivo correlates with changes in serum cytokines.

Antiviral mode of action of bovine dialyzable leukocyte extract against human immunodeficiency virus type 1 infection

BACKGROUND

Bovine dialyzable leukocyte extract (bDLE) is derived from immune leukocytes obtained from bovine spleen. DLE has demonstrated to reduce transcription of Human Immunodeficiency Virus Type 1 (HIV-1) and inactivate the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway. Therefore, we decided to clarify the mode of antiviral action of bDLE on the inhibition of HIV-1 infection through a panel of antiviral assays.

RESULTS

The cytotoxicity, HIV-1 inhibition activity, residual infectivity of bDLE in HIV-1, time of addition experiments, fusion inhibition of bDLE for fusogenic cells and the duration of cell protection even after the removal of bDLE were all assessed in order to discover more about the mode of the antiviral action.HIV-1 infectivity was inhibited by bDLE at doses that were not cytotoxic for HeLa-CD4-LTR-β-gal cells. Pretreatment of HIV-1 with bDLE did not decrease the infectivity of these viral particles. Cell-based fusion assays helped to determine if bDLE could inhibit fusion of Env cells against CD4 cells by membrane fusion and this cell-based fusion was inhibited only when CD4 cells were treated with bDLE. Infection was inhibited in 80% compared with the positive (without EDL) at all viral life cycle stages in the time of addition experiments when bDLE was added at different time points. Finally, a cell-protection assay against HIV-1 infection by bDLE was performed after treating host cells with bDLE for 30 minutes and then removing them from treatment. From 0 to 7 hours after the bDLE was completely removed from the extracellular compartment, HIV-1 was then added to the host cells. The bDLE was found to protect the cells from HIV-1 infection, an effect that was retained for several hours.

CONCLUSIONS

bDLE acted as an antiviral compound and prevented host cell infection by HIV-1 at all viral life cycle stages. These cell protection effects lingered for hours after the bDLE was removed. Interestingly, bDLE inhibited fusion of fusogenic cells by acting only on CD4 cells. bDLE had no virucidal effect, but could retain its antiviral effect on target cells after it was removed from the extracellular compartment, protecting the cells from infection for hours.bDLE, which has no reported side effects or toxicity in clinical trials, should therefore be further studied to determine its potential use as a therapeutic agent in HIV-1 infection therapy, in combination with known antiretrovirals.

Cell mediated immunity to meet the avian influenza A (H5N1) challenge

Avian influenza A subtype H5N1 virus with its recombination potential with the human influenza viruses presents a threat of producing a pandemic. The consensus is that the occurrence of such a pandemic is only a matter of time. This is of great concern, since no effective vaccine is available or can be made before the occurrence of the event. We present arguments for the use of cell mediated immunity for the prevention of the infection as well as for the treatment of infected patients. Transfer factor (TF), an immunomodulator of low molecular weight capable of transferring antigen-specific cell mediated immune information to T-lymphocytes, has been used successfully over the past quarter of a century for treating viral, parasitic, and fungal infections, as well as immunodeficiencies, neoplasias, allergies and autoimmune diseases. Moreover, several observations suggest that it can be utilised for prevention, transferring immunity prior to infection. Because it is derived from lymphocytes of immune donors, it has the potential to answer the challenge of unknown or ill-defined pathogens. Indeed, it is possible to obtain an antigen-specific TF preparation to a new pathogen before its identification. Thus, a specific TF to a new influenza virus can be made swiftly and used for prevention as well as for the treatment of infected patients.

Non-induced leukocyte extract reduces HIV replication and TNF secretion

According to UNAIDS, the global HIV/AIDS epidemic increased to 40 million the number of people living with the virus around the world. Dialyzable leukocyte extract obtained by our group is a low molecular weight dialyzable material from peripheral human leukocytes previously in vitro induced with Sendai virus (DLE-ind), and more recently, from non-induced leukocytes (DLE n/i). Previous results have shown the ability of DLE-ind to inhibit HIV in vitro replication in MT4 cell; to reduce TNFalpha secretion, and to delay in vivo progression to AIDS in early stage of HIV infection. In this work we present evidences that DLE n/i also inhibits HIV in vitro replication and reduces TNFalpha secretion in human whole blood like DLE obtained from induced leukocytes. Taking together these results show that both properties of DLE, HIV in vitro inhibition and TNF production modulation, are not dependent on in vitro Sendai virus induction of leukocytes.

Transfer factors as immunotherapy and supplement of chemotherapy in experimental pulmonary tuberculosis

Problems of logistics, compliance and drug resistance point to an urgent need for immunotherapeutic strategies capable of shortening the current six month antibiotic regimens used to treat tuberculosis. One potential immunotherapeutic agent is transfer factors. Transfer factors (TF) are low molecular weight dialysable products from immune cells which transmit the ability to express delayed-type hypersensitivity (DTH) and cell mediated immunity from sensitized donors to nonimmune recipients. In this study we determined the efficiency of TF as immunotherapy to treat experimental tuberculosis. When BALB/c mice are infected via the trachea with Mycobacterium tuberculosis H37Rv there is an initial phase of partial resistance dominated by Th-1 type cytokines plus tumour necrosis factor-alpha (TNFalpha) and the inducible isoform of nitric oxide synthase (iNOS), followed by a phase of progressive disease characterized by increasing expression of IL-4, diminished expression of TNFalpha and iNOS, and low DTH. Animals in this late progressive phase of the disease (day 60) were treated with different doses of TF (one injection per week) obtained from spleen cells when the peak of immune protection in this animal model is reached (day 21), or with different doses of TF from peripheral leucocytes of PPD + healthy subjects. We show here that the treatment with murine or human TF restored the expression of Th-1 cytokines, TNFalpha and iNOS provoking inhibition of bacterial proliferation and significant increase of DTH and survival. This beneficial effect was dose dependent. Interestingly, murine TF in combination with conventional chemotherapy had a synergistic effect producing significant faster elimination of lung bacteria loads than chemotherapy alone.

Characterization of the cellular immune response in American cutaneous leishmaniasis

The in vitro and in vivo cellular immune reactivity of 49 patients with American cutaneous leishmaniasis (ACL) was evaluated using mitogens and parasite antigens. Patients were examined before treatment and were classified on the basis of clinical and histopathological criteria as suffering localized cutaneous leishmaniasis (LCL, 32 patients) or mucocutaneous leishmaniasis (MCL, 11 patients). A small group (6 patients) of treated diffuse cutaneous leishmaniasis (DCL) patients was also examined. The lymphocyte proliferative responses to PHA were significantly lower than those of controls (87 individuals, from either endemic or nonendemic zones) in LCL, and particularly MCL. Con A responses were, however, effectively normal in these patients. Both in vivo and in vitro cellular immune responses to leishmanial antigens were significantly greater in MCL and LCL patients than in the controls, the intensity of the reactions being by far the greatest in MCL. DCL patients demonstrated a complete absence of specific immune responsiveness both in vivo and in vitro. The significance of these results in the mechanisms leading to the resolution of the infection or production of pathologic lesions is discussed.