Low-dose amphotericin B and murine dialyzable spleen extracts protect against systemic candida infection in mice

CD80 Expression Correlates with IL-6 Production in THP-1-Like Macrophages Costimulated with LPS and Dialyzable Leukocyte Extract (Transferon®)

Transferon® is a complex drug based on a mixture of low molecular weight peptides. This biotherapeutic is employed as a coadjuvant in clinical trials of several diseases, including viral infections and allergies. Given that macrophages play key roles in pathogen recognition, phagocytosis, processing, and antigen presentation, we evaluated the effect of Transferon® on phenotype and function of macrophage-like cells derived from THP-1 monocytes. We determined the surface expression of CD80 and CD86 by flow cytometry and IL-1β, TNF-α, and IL-6 levels by ELISA. Transferon® alone did not alter the steady state of PMA-differentiated macrophage-like THP-1 cells. On the contrary, simultaneous stimulation of cells with Transferon® and LPS elicited a significant increase in CD80 (P ≤ 0.001) and CD86 (P ≤ 0.001) expression, as well as in IL-6 production (P ≤ 0.05) compared to the LPS control. CD80 expression and IL-6 production exhibited a positive correlation (r = 0.6, P ≤ 0.05) in cells exposed to Transferon® and LPS. Our results suggest that the administration of Transferon® induces the expression of costimulatory molecules and the secretion of cytokines in LPS-activated macrophages. Further studies are necessary to determine the implication of these findings in the therapeutic properties of Transferon®.

Local delivery polymer provides sustained antifungal activity of amphotericin B with reduced cytotoxicity

IMPACT STATEMENT

Amphotericin B (AmB) is an effective and commonly used antifungal agent. However, nephrotoxicity and poor solubility limits its usage. The proposed polymerized cyclodextrin (pCD) system therefore is an attractive method for AmB delivery, as it retains the antifungal activity of AmB while decreasing toxicity, and confining drug release to the local environment. This system could potentially be used for both prevention and treatment of established fungal infections, as AmB is toxic to fungus whether associated or released from pCD.

Amphotericin B-copper (II) complex alters transcriptional activity of genes encoding transforming growth factor-beta family members and related proteins in renal cells

BACKGROUND

Several chemical modifications have been developed to overcome the toxicity of amphotericin B (AmB). Oxidized forms of AmB (AmB-ox), which may occur in patient's circulation during therapy, are as toxic as AmB. Complexes with copper (II) ions (AmB-Cu²⁺) have been reported to be less toxic to human cells. Previous studies showed that AmB changed the expression of transforming growth factor-beta (TGF-β). Therefore, the objective of this study was to investigate the influence of AmB and its modified forms on the expression of genes encoding for TGF-β family members and related proteins in renal cells.

METHODS

Human renal proximal tubule cells (RPTEC) were treated with AmB-Cu²⁺, AmB, or the oxidized form AmB-ox. The expression of TGF-β family members and related genes was determined using oligonucleotide microarrays. TGF-β1 protein level was determined using ELISA method. The mRNA level of TGF-β isoforms, TGF-β receptors and differentiating genes was evaluated by real-time RT-qPCR.

RESULTS

AmB-Cu²⁺ increased the mRNA levels of TGF-β1 and TGF-β2 isoforms and two genes encoding receptors: TGFBR1 and TGFBR2. TGF-β1 protein level in culture medium was not increased after stimulation with AmB-Cu²⁺. Microarray analysis revealed changes in both pro-fibrotic and anti-fibrotic genes.

CONCLUSIONS

These results suggest that AmB-Cu²⁺ may induce repair mechanisms in renal proximal tubule cells via changes in the expression of genes involved in intracellular signaling.

A new form of amphotericin B - the complex with copper (II) ions - downregulates sTNFR1 shedding and changes the activity of genes involved in TNF-induced pathways: AmB-Cu2+ downregulates sTNFR1 shedding and changes the activity of genes involved in TNF-induced pathways

BACKGROUND

A new form of amphotericin B (AmB)- complex with copper (II) ions (AmB-Cu²⁺) - is less toxic to human renal cells. Cytokines, including Tumor Necrosis Factor (TNF), are responsible for nephrotoxicity observed in patients treated with AmB. Another problem during therapy is the occurrence of oxidized forms of AmB (AmB-ox) in patients' circulation. To elucidate the molecular mechanism responsible for the reduction of the toxicity of AmB-Cu²⁺, we evaluated the expression of genes encoding TNF and its receptors alongside encoding proteins involved in TNF-induced signalization.

METHODS

Renal cells (RPTECs) were treated with AmB, AmB-Cu²⁺ or AmB-ox. The expression of TNF and its receptors was evaluated by ELISA tests and real-time RT-qPCR. The expression of TNF-related genes was appointed using oligonucleotide microarrays.

RESULTS

Only sTNFR1 was detected, and its level was lower in AmB-Cu²⁺- and AmB-ox-treated cells. TNFR1 mRNA was downregulated in AmB-ox, while TNFR2 mRNA was upregulated in AmB and AmB-Cu²⁺. Several changes in the expression of TNF-related genes coincided with changes in the expression of TNF receptors.

CONCLUSIONS

The lower toxicity of AmB-Cu²⁺ could result from the changes in the expression of TNF receptors, which coincided with the changes in the expression of genes encoding proteins involved in TNF-induced pathways. This situation might subsequently result in a changes in intracellular signalization and influence the toxicity of tested forms of AmB on renal cells.

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.

Swine Dialyzable Spleen Extract as Antiviral Prophylaxis

Worldwide, the most highly consumed meat is of porcine origin. The production and distribution of swine meat are affected by diverse health matters, such as influenza and diarrhea, which cause head losses and require the use of antibiotics and other drugs in hog farms. To stimulate newborn piglet immune responses and increase resistance to infections, we developed a spray-drying technique to produce dried swine dialyzable spleen extract (sDSE), an immunomodulator. Based on the size-exclusion ultra performance liquid chromatography quantitative analysis, it was possible to recover up to 58% of the product after the drying process. The biological activity of orally administered dried sDSE increased mouse survival and induced cytokine production in a herpes infection model.