Egbert Piasecki

Interferon responses in schizophrenia and major depressive disorders

The spontaneous and induced interferon (IFN) production in whole blood cultures was examined in 45 psychiatric inpatients and in 65 normal controls. Among inpatients there were 32 who were chronic schizophrenics (14 women, 18 men) and 13 who were severely depressed (11 women, 2 men). The analysis of the pooled results of assays in the heterogeneous population showed that leukocytes of the psychiatric patients produced significantly lower levels of IFN after stimulation with virus (NDV), lipopolysaccharide (LPS), and IFN spontaneously released without the inducers that control cells. In contrast, there was no difference between the psychiatric patients and controls in IFN response to phytohemagglutinin and phorbol myristate acetate (PHA + PMA). The results apparently confirmed observations made by Moises et al (1985) and Katila et al (1989). We have also tested our hypothesis that the statistics may mask the individual pattern of IFN response related to the specific psychiatric diagnosis, however. In fact, in the group of chronic schizophrenics we have found either high or low responders to all IFN inducers (NDV, PHA + PMA and LPS). Furthermore, the patients with high IFN response had dominant positive symptoms of schizophrenia (delusions, hallucinations, bizarre behavior and thought disorder). Whereas, in the patients with low IFN response the negative symptoms prevailed (asociality or withdrawal, flat affect, attention impairment, abolition or apathy). In plasma samples of schizophrenics, factors were detected that transferred a hypersensitivity to the IFN inducers to normal donor leukocytes. For instance, in leukocytes cultured in the presence of plasma from schizophrenics, there were 71% of high IFN responders after stimulation with NDV, versus 26% of high IFN responders in the presence of plasma from normal controls. We suggest that the factors may belong to the class of opioid peptides, which interact with the production of cytokines including IFNs.

Organoselenides as potential immunostimulants and inducers of interferon gamma and other cytokines in human peripheral blood leukocytes

A number of organoselenium compounds have been described as anti-inflammatory, antioxidant, glutathione peroxidase-like agents and inhibitors of prostaglandin synthesis. Here we report that bis [2-(N-phenyl-carboxamido)]phenyl diselenide, 2-phenyl-1,2-benzisoselenazol-3(2H)-one (Ebselen) and related compounds are inducers of interferon gamma (IFN-γ) and tumor necrosis factor (TNF) in human peripheral blood leukocytes. The IFN and TNF response was rapid, occurring within 20 h, and high-up to 1000 and 2000 units ml−1-and was clearly related to the dosage and the structure of the compounds. The action of the compounds and phytohemagglutinin was synergistic. The IFN gamma and TNF production was reduced after removing adherent cells. Although the mode of action of the compounds is not known, they appear to interact directly or indirectly with both adherent and non-adherent leukocytes, and stimulate the synthesis of a set of different cytokines including factors controlling the cell proliferation. Therefore, organoselenides may be regarded as the biological response modifiers.

Cyclophosphamide and IL-12-transduced DCs enhance the antitumor activity of tumor antigen-stimulated DCs and reduce Tregs and MDSCs number.

A hostile tumor microenvironment, characterized by an abundance of T regulatory cells and myeloid-derived suppressor cells (MDSCs), considerably limits the efficacy of dendritic cell (DC)-based vaccines. The intention of this study was to enhance the antitumor activity of vaccines consisting of bone marrow-derived DCs stimulated with TAg (BMDC/TAg) via single administration of cyclophosphamide and multiple injections of interleukin (IL)-12-transduced DCs (BMDC/IL-12). The combined chemoimmunotherapy was applied in the treatment of mice with subcutaneously (SC) growing, advanced MC38 colon carcinoma. The highest level of tumor growth inhibition, accompanied by high cytotoxic activity of effector cells, and their increased influx into tumor tissue, was observed after application of cyclophosphamide in combination with BMDC/TAg and BMDC/IL-12. The effect was probably associated with the elimination of T regulatory cells from spleens and tumors, but most of all with changes in the number and differentiation stage of MDSCs. After the therapy, the percentage of granulocytic and monocytic MDSCs in spleens was significantly lower than in the control group. Moreover, MDSCs derived from spleens and tumors showed increased expression of MHC class II, which may indicate the higher maturation stage of the myeloid cells as well as their enhanced capacity toward antigen presentation. The obtained data indicate that the optimal composition of antitumor vaccines able to limit the suppressor activity of MDSCs is essential to enhance the elimination of tumor cells and to achieve an optimal therapeutic effect.

The effects of killer cell immunoglobulin-like receptor (KIR) genes on susceptibility to HIV-1 infection in the Polish population

Killer cell immunoglobulin-like receptors (KIR) are the most polymorphic receptors of natural killer (NK) cells. Their activity diversifies the functions of NK cells in the antiviral immune response, so the presence of certain KIR may affect transmission of HIV-1. The aim of the study was to evaluate the influence of KIR genes on the susceptibility to HIV-1 infection in the Polish population depending on the route of exposure. We determined the frequencies of activating (2DS1, 2DS2, 2DS3, 2DS4f, 2DS4del, 2DS5, 3DS1) and inhibitory (2DL1, 2DL2, 2DL3, 2DL5, 3DL1) KIRs in HIV-1-positive patients (n = 459), individuals exposed to HIV-1 but uninfected (EU, n = 118) and in uninfected, healthy blood donors (BD, n = 98). Analysis was performed using stepwise logistic regression. Apart from KIRs, CCR5-∆32, and CCR2-64I, alleles were also analyzed, as we knew or suspected that these features could affect susceptibility to HIV infection. The regression confirmed the protective effect of CCR5-∆32 (OR = 0.25, p = 0.006) and CCR2-64I (OR = 0.59, p = 0.032) against HIV infection. Among KIR genes, 2DL3 was found to be a protective factor (OR = 0.30, p = 0.015). A similar effect was seen for 3DS1 but only in intravenous drug users (IDUs) (OR = 0.30, p = 0.019), not in sexually exposed people. 2DL5 was found to be a factor facilitating HIV infection (OR = 2.13, p = 0.013). A similar effect was observed for 2DL2 but only in females (OR = 2.15, p = 0.040), and 2DS1 in IDUs (OR = 3.03, p = 0.022). Our results suggest a beneficial role of KIR3DS1 and 2DL3 supporting resistance to HIV infection and a harmful effect of 2DS1, 2DL5, and 2DL2 genes promoting HIV acquisition.

Frequency of human endogenous retroviral sequences (HERV) K113 and K115 in the Polish population, and their effect on HIV infection.

Background The human genome contains about 8% of endogenous retroviral sequences originated from germ cell infections by exogenous retroviruses during evolution. Most of those sequences are inactive because of accumulation of mutations but some of them are still capable to be transcribed and translated. The latter are insertionally polymorphic HERV-K113 and HERV-K115. It has been suggested that their presence and expression was connected with several human diseases. It is also believed that they could interfere with the replication cycle of exogenous retroviruses, including HIV. Results Prevalence of endogenous retroviral sequences HERV-K113 and HERV-K115 was determined in the Polish population. The frequencies were found as 11.8% for HERV-K113 and 7.92% for HERV-K115. To verify the hypothesis that the presence of these HERVs sequences could affect susceptibility to HIV infection, comparison of a control group (HIV-negative, not exposed to HIV; n = 303) with HIV-positive patients (n = 470) and exposed but uninfected (EU) individuals (n = 121) was performed. Prevalence of HERV-K113 and HERV-K115 in the EU group was 8.26% and 5.71%, respectively. In the HIV(+) group we detected HERV-K113 sequences in 12.98% of the individuals and HERV-K115 sequences in 7.23% of the individuals. There were no statistically significant differences between groups studied. Conclusion The frequency of HERV-K113 and HERV-K115 sequences in Poland were found to be higher than usually shown for European populations. No relation between presence of the HERVs and HIV infection was detected.

Antitumor effect of murine dendritic and tumor cells transduced with IL-2 gene

Interleukin (IL-) 2 acts on a number of types of immune cells promoting their effector functions. To replace systemic administration of recombinant form of this cytokine, various genetically modified cells have been used in different preclinical models for tumor growth inhibition. In this study, dendritic or tumor cells transduced with retroviral vector carrying IL-2 gene (JAWS II/IL-2, X63/IL-2, MC38/IL-2 cells) alone or combined with tumor antigenstimulated dendritic cells (JAWS II/TAg) were exploited to treat colon carcinoma MC38-bearing mice. After the peritumoral injection of vaccine cells, the tumor growth delay and the increase in the number of tumor infiltrating CD4+ and CD8+ T lymphocytes were noted. A considerable increase in CD4+ cell influx into tumor tissue was observed when JAWS II/IL-2 cells or JAWS II/TAg with syngeneic MC38/IL-2 cells were applied. The increase in intensity of CD8+ cell infiltration was associated with immune reaction triggered by the same combination of applied cells or JAWS II/TAg with allogeneic X63/IL-2 cells. The effect observed in vivo was accompanied by MC38/0 cell specific cytotoxic activity of spleen cells in vitro. Thus, the application of vaccines, including IL-2-secreting cells of various origins, was able to induce different antitumor responses polarized by exogenous IL-2 and the encountered tumor antigen.

Reaction of bis[(2-chlorocarbonyl)phenyl] Diselenide with Phenols, Aminophenols, and Other Amines towards Diphenyl Diselenides with Antimicrobial and Antiviral Properties

A reaction of bis[(2-chlorocarbonyl)phenyl] diselenide with various mono and bisnucleophiles such as aminophenols, phenols, and amines have been studied as a convenient general route to a series of new antimicrobial and antiviral diphenyl diselenides. The compounds, particularly bis[2-(hydroxyphenylcarbamoyl)]phenyl diselenides and reference benzisoselenazol-3(2H)-ones, exhibited high antimicrobial activity against Gram-positive bacterial species (Enterococcus spp., Staphylococcus spp.), and some compounds were also active against Gram-negative E. coli and fungi (Candida spp., A. niger). The majority of compounds demonstrated high activity against human herpes virus type 1 (HHV-1) and moderate activity against encephalomyocarditis virus (EMCV), while they were generally inactive against vesicular stomatitis virus (VSV).

Inhibition of vesicular stomatitis virus replication in the course of HIV infection in patients with different stages of immunodeficiency.

The replication of vesicular stomatitis virus (VSV) in isolated human leukocytes has been used to measure the level of nonspecific antiviral immunity. However, during infection with some pathogens, the main effect observed is caused by interaction between the pathogen and VSV. This was also noted in advanced stages of HIV infection, when an inverse association between HIV viral load and VSV replication was found. The mutual effect was markedly stronger than the correlation between the VSV replication level and CD4(+) T-cell count. Since successful antiretroviral therapy is associated with a decrease in HIV viremia to undetectable levels, the effect of such therapy on VSV replication was expected and confirmed in this investigation. In fact, increased VSV titers were observed together with decreased HIV viral load, particularly in the case of efficient therapeutic schemes, for example those including lopinavir/ritonavir. The results showed that VSV replication capacity reflected the progression of HIV infection. Moreover, the presence of interferon in the plasma of AIDS patients was found to be only partially responsible for the inhibition of VSV replication. The results suggest a specific HIV-VSV interaction, whether direct or indirect. Thus the VSV replication assay may be applied in evaluating the stage of HIV infection.

Treatment with cyclophosphamide supported by various dendritic cell-based vaccines induces diversification in CD4+ T cell response against MC38 colon carcinoma

The present study shows that an application of cyclophosphamide (CY) supported by dendritic cell (DC)-based vaccines affected differentiation of the activity of CD4+ T cell subpopulations accompanied by an alteration in CD8+ cell number. Vaccines were composed of bone marrow-derived DCs activated with tumor cell lysate (BM-DC/TAgTNF-α) and/or genetically modified DCs of JAWS II line (JAWS II/ Neo or JAWS II/IL-2 cells). Compared to untreated or CY-treated mice, the combined treatment of MC38 colon carcinoma-bearing mice resulted in significant tumor growth inhibition associated with an increase in influx of CD4+ and CD8+ T cells into tumor tissue. Whereas, the division of these cell population in spleen was not observed. Depending on the nature of DC-based vaccines and number of their applications, both tumor infiltrating cells and spleen cells were able to produce various amount of IFN-γ, IL-4 and IL-10 after mitogenic ex vivo stimulation. The administration of CY followed by BM-DC/TAgTNF-α and genetically modified JAWS II cells, increased the percentage of CD4+T-bet+ and CD4+GATA3+ cells and decreased the percentage of CD4+RORγt+ and CD4+FoxP3+ lymphocytes. However, the most intensive response against tumor was noted after the ternary treatment with CY + BM-DC/TAgTNF-α + JAWS II/IL-2 cells. Thus, the administration of various DC-based vaccines was responsible for generation of the diversified antitumor response. These findings demonstrate that the determination of the size of particular CD4+ T cell subpopulations may become a prognostic factor and be the basis for future development of anticancer therapy.

The effects of peritumoral therapeutic vaccination with IL-2-secreting cells on growth of MC38 colon tumours in mice, local NO production and sentinel lymph node cells activation

The antitumor effects of cytokines used in cancer immunotherapy depend on the actual balance between the host immune system and a growing tumor. One of the most potent regulatory molecules that play a critical role in generating a successful immune response is interleukin-2 (IL-2), which like other cytokines, acts in a paracrine and autocrine manner. The cytokine induces a broad spectrum of biological events, which in some cases lead to tumor regression. Among others IL-2 stimulates the proliferation of CD8+T cells and their IFN-y production. By initiation of cascade of secondary cytokines, especially IFN and TNF-a, IL-2 is also involved in activation of macrophages. Activated macrophages produce nitric oxide (NO), defined as an effector molecule that can kill or inactivate target cells.