Tumor immunity is primarily mediated by cells as CD8+ cytotoxic T lymphocytes (CTL) recognize tumor antigen by MHC class I molecules. But most tumors are associated with a decreased expression of MHC class I to escape the antitumor immunity of the host. Our previous data have demonstrated that MPL has an antitumor effect on metastatic lung cancer of B16 melanoma with enhancing cytotoxicity due to increase of IFN-gamma and IL-2, and decrease of IL-4, which indicates the stimulation of type 1 helper T cells (Th1). To determine the effects of MPL, IFN-gamma, TNF-alpha, and IL-1 alpha on MHC class I expression of B16 melanoma cells, we evaluated the expression of MHC class I molecules with treatments of MPL, IFN-gamma, TNF-alpha, and IL-1 alpha by flow cytometry. The supernatant of MPL-treated spleen cells in vitro upregulated the expression of MHC class I molecules of B16 melanoma cells compared to the control supernatant of spleen cells. The MHC class I expression of B16 melanoma cells treated with IFN-gamma, but not TNF-alpha or IL-1 alpha, increased in a time-dependent manner. In conclusion, MPL upregulated MHC class I expression of B16 melanoma cells by activating spleen cells via IFN-gamma. These data suggest that increased IFN-gamma by MPL is responsible for the upregulation of MHC class I expression to augment cytotoxicity. Therefore, we suggest that MPL could play an important role in immunotherapy.
Adjuvants, Immunologic/pharmacology* ; Animal ; Histocompatibility Antigens Class I/biosynthesis* ; Interferon Type II/pharmacology ; Interferon Type II/biosynthesis* ; Lipid A/pharmacology ; Lipid A/analogs & derivatives* ; Mice ; Mice, Inbred C57BL ; Tumor Cells, Cultured ; Up-Regulation (Physiology)

In order to investigate cytokine productions in patients undergoing continuous ambulatory peritoneal dialysis (CAPD), we studied the production of interleukin (IL)-1 beta, -6 and interferon (IFN)-gamma by cultured peripheral blood mononuclear cells (PBMC) in peritonitis-free CAPD patients. The correlation of cytokine production with plasma parathyroid hormone (PTH) and albumin levels was also evaluated. While the release of IL-1 beta was not markedly different from controls release of IL-6 from 24-hour cultured PBMCs was significantly greater than that of controls, (Mean +/- S.D., IL-6: 2186.8 +/- 1217.9 pg/ml, vs 1516.3 +/- 767.9, P <0.05). The addition of lipopolysaccharide (LPS, 10 micrograms/ml, significantly stimulated IL-1 beta and -6 production of PBMCs in CAPD patients and controls, compared to an unstimulated condition. The LPS-induced IL-1 beta production was also not markedly different from controls, whereas LPS-induced IL-6 production was significantly higher than controls (IL-6: 13,220.7 +/- 7177.4 vs 7411.4 +/- 1236.9, P <0.05). However, the percentage increases of IL-6 production stimulated with LPS in CAPD patients were not significantly different from controls (p > 0.05). No difference of baseline IFN-gamma was detected between CAPD patients controls, but phytohemagglutinin (PHA, 10 micrograms/ml)-stimulated IFN-gamma release was significantly higher in CAPD patients than controls (2425.9 +/- 1565.0 pg/ml vs 1364.0 +/- 755.1, P <0.05). There was no significant correlation between PTH and, IL-1 beta, serum albumin level and LPS-stimulated IL-6 production (r = 0.54, P <0.05). In conclusion, CAPD seems to partly induce activation of PBMCs with an enhanced release of IL-6 and IFN-gamma, and CAPD patients with higher serum albumin levels tend to show higher IL-6 production in immune response.
Adult ; Cells, Cultured ; Female ; Human ; Interferon Type II/biosynthesis* ; Interleukin-1/biosynthesis* ; Interleukin-6/biosynthesis* ; Male ; Middle Age ; Monocytes/metabolism ; Parathyroid Hormones/blood ; Peritoneal Dialysis, Continuous Ambulatory* ; Serum Albumin/analysis

The cytokine pattern on viral antigen recognition is believed to exert a profound influence on the resolution of viral infections and viral clearance. This study was initiated to investigate whether a cytokine imbalance oriented toward Th2 type response plays a role in chronic hepatitis B. Cytokine profiles of peripheral blood mononuclear cells associated with chronic hepatitis B were analysed by RT-PCR. Upon HBsAg stimulation, expression of IFN-gamma, IL-2, IL-4, and IL-10 was detected in 41%, 8%, 41%, and 50% of the patients, respectively. Among these cytokines, the expression of IFN-gamma was associated with high levels of serum AST/ALT. However, we could not prove that Th2 type cytokines had a protective effect on hepatocytes. Upon HBxAg stimulation, there was no recognizable association of cytokine patterns with AST/ALT levels. In conclusion, production of a Th1 cytokine, IFN-gamma, by HBsAg-reactive cells was associated with hepatocyte damage in chronic hepatitis B, while no counteracting effect of Th2 cytokines produced by those cells was observed.
Cytokines/genetics ; Cytokines/biosynthesis* ; Hepatitis B Surface Antigens/pharmacology ; Hepatitis B Surface Antigens/immunology* ; Hepatitis B, Chronic/immunology* ; Human ; Interferon Type II/genetics ; Interferon Type II/biosynthesis ; Leukocytes, Mononuclear/immunology ; Liver/cytology ; Recombinant Fusion Proteins/pharmacology ; Recombinant Fusion Proteins/immunology ; Th1 Cells/immunology* ; Th1 Cells/drug effects ; Th2 Cells/immunology* ; Th2 Cells/drug effects ; Trans-Activators/pharmacology ; Trans-Activators/immunology*

We have investigated in vitro proliferative responses of peripheral blood mononuclear cells and productions of interferon-gamma and soluble interleukin-2 receptors by these cells from 6 patients with chronic active hepatitis B immediately before and 24 hours after a single intravenous injection of 100 mg of polyadenylic.polyuridylic acid. Cell proliferations were assessed by the technique of tritiated-thymidine incorporation and productions of interferon-gamma and soluble interleukin-2 receptors were measured by enzyme-linked immunosorbent assay. The administration of polyadenylic.polyuridylic acid to the patients has resulted in significant increases of in vitro proliferations of their peripheral blood mononuclear cells as well as productions of interferon-gamma by these cells. However, in vitro productions of soluble interleukin-2 receptors were not changed significantly. These results suggest that the enhanced cellular responses by polyadenylic.polyuridylic acid might be due to the increased sensitivity rather than the increased expression of cellular interleukin-2 receptor.
Adult ; Hepatitis B/*immunology ; Hepatitis, Chronic/*immunology ; Human ; Immunity, Cellular/drug effects ; Interferon Type II/biosynthesis ; Leukocytes, Mononuclear/*drug effects/immunology ; Male ; Middle Age ; Poly A-U/*pharmacology ; Receptors, Interleukin-2/biosynthesis ; Solubility

For those with allergy, vaccination with a specific allergen has often been used as a major therapeutic measure. However, the universal application of this technique in clinics have been restricted due to its low success rates and the risk of active systemic anaphylactic shock (ASAS). In this regard, we constructed a fusion protein (OVA-DT), ovalbumin (OVA) fused with diphtheria toxin protein (DT), which may exert a specific cytotoxicity to cells bearing OVA-specific IgE. Its therapeutic effect was evaluated in mice (BALB/c) sensitized with OVA (Os-mice). OVA challenges to the OVA-sensitized mice (Os-mice) caused ASAS to death within 30 min, but OVA-DT treatment afforded mice complete protection. When OVA-DT was treated to the Os-mice, none showed the signs of ASAS when re-challenged 48 h after the treatment. OVA-DT itself was not found to be toxic or allergenic in normal mice. The effect of OVA-DT on the biological functions of mast cells was also studied. Binding of OVA-DT to OVA-specific IgE bearing mast cells and the inhibition of histamine release from these cells were observed. In addition, OVA-DT treatment inhibited the proliferation of OVA-specific B cells in mice. In Os-mice treated with OVA-DT, levels of anti-OVA IgG2a in serum and the production of IFN-gamma by splenic lymphocytes were found to increase, but the production of IL-4 by these cells decreased. Re-direction of cytokine profiles from OVA-specific Th2 to OVA-specific Thl is suggested. These results indicate that OVA-DT can protect Os-mice from ASAS due to OVA challenge, because it inactivates OVA-specific IgE-expressing cells, including mast cells and B cells.
Anaphylaxis/prevention | control* ; Animal ; B-Lymphocytes/immunology ; Female ; Histamine Release/drug effects ; IgE/metabolism ; Interferon Type II/biosynthesis ; Interleukin-4/biosynthesis ; Lymphocyte Transformation/drug effects ; Mast Cells/metabolism ; Mice ; Mice, Inbred BALB C ; Ovalbumin/immunology* ; Recombinant Fusion Proteins/therapeutic use*

The heart transplantation-associated accelerated graft arteriosclerosis (AGAS) is one of the major causes of cardiac allograft failure. We investigated the early time-course of expresssion patterns of cytokines, transcription factor, and its inhibitor in the intraabdominally transplanted mice hearts that differed only in the D locus of class I histocompatibility antigen. The allograft hearts were harvested at 1-3, 5, 7, 14, 28, and 42 days after the transplantation, and the expressions of NF-kappaB/I-kappaB and cytokines (TNF-alpha , INF-gamma) were examined in these specimens. The expressions of TNF-alpha and INF-gamma were observed on day 1, peaking on day 5 and 7, respectively. Activated NF-kappaB (p65) expression was present on the cytoplasm and perinuclear area in the endothelial cells of coronary arteries on day 1. The peak of translocation of NF-B from cytoplasm to nucleus appeared on day 5 in the endothelial cells, myocytes, and leukocytes within the vessels, and remained elevated until day 42. The I-kappaB expression gradually increased from day 1 until day 5, but a remarkable decrease was detected on day 7. Our data suggest that the increased expressions of NF-kappaB/I-kappaB and cytokines (TNF-alpha, INF-gamma) play an important role in inducing immune responses in the donor allograft heart and hence the blockage of the expressions might be mandatory to avoid a potential graft failure.
Animal ; Chronic Disease ; Coronary Arteriosclerosis/etiology/*metabolism ; Cytokines/*biosynthesis ; *Graft Rejection ; *Heart Transplantation ; Histocompatibility Antigens Class I/analysis ; Intercellular Adhesion Molecule-1/biosynthesis ; Interferon Type II/biosynthesis ; Mice ; NF-kappa B/*biosynthesis ; Transplantation, Homologous ; Tumor Necrosis Factor/biosynthesis ; Vascular Cell Adhesion Molecule-1/biosynthesis

Phagocytosis of serum- and IgG-opsonized zymosan (SOZ and IOZ, respectively) particles into J774A.1 macrophages induced apoptosis of the cells, accompanied by the expression of p21(WAF1), one of cyclin-dependent protein kinase (CDK) inhibitors. Furthermore, phagocytosis of SOZ and IOZ particles into macophages induced superoxide formation. Tat-superoxide dismutase (SOD), which is readily transduced into the cells using Tat-domain, protected the cells from the apoptosis induced by phagocytosis of SOZ and IOZ particles. lipopolysaccharide (LPS)/interferon-gamma (IFN-gamma) also caused the apoptosis of the cells. However, Tat-SOD could not protect the cells from LPS/IFN-gamma induced apoptosis, suggesting that apoptosis mechanisms involved are different from each other. In the present study, we determined the amounts of nitric oxide (NO) produced by SOZ, IOZ, and LPS/IFN-gamma, and found that SOZ and IOZ did not induce the generation of NO in macrophages, whereas LPS/ IFN-gamma did. The apoptosis due to phagocytosis was accompanied with the release of cytochrome c from mitochondrial membrane to cytosolic fraction. Furthermore, SOZ and IOZ induced the cleavage of procasapase-3 (35 kDa) to give rise to an active caspase-3 (20 kDa), which was blocked by Tat- SOD but not by 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO), a scavenger of NO. On the other hand, LPS/IFN-gamma caused the activation of procaspase-3, which was blocked by PTIO but not by Tat-SOD. Taken together, phagocytosis of SOZ and IOZ particles induced apoptosis through superoxide but not NO in macrophages, accompanied with the release of cytochrome c and the activation of caspase-3.
Apoptosis/*immunology ; Caspases/metabolism ; Cell Line ; Cyclins/biosynthesis ; Cytochromes c/metabolism ; Immunoglobulin G/*immunology ; Interferon Type II/pharmacology ; Lipopolysaccharides/pharmacology ; Macrophages/*immunology/metabolism ; Nitric Oxide/*metabolism ; Opsonins/immunology ; Phagocytosis/*physiology ; Superoxide Dismutase/metabolism ; Superoxides/*metabolism ; Zymosan

Although there are many reports on the splenic (systemic) T cell response after Toxoplasma gondii infection, little information is available regarding the local T cell responses of peritoneal exudate cells (PEC) and gut intraepithelial lymphocytes (IEL) following peroral infection with bradyzoites. Mice were infected with 40 cysts of the 76K strain of T. gondii, and then sacrificed at days 0, 1, 4, 7 and 10 postinfection (PI). The cellular composition and T cell responses of PEC and IEL were analyzed. The total number of PEC and IEL per mouse increased after infection, but the ratio of increase was higher in IEL. Lymphocytes were the major component of both PEC and IEL. The relative percentages of PEC macrophages and neutrophils/eosinophils increased significantly at day 1 and 4 PI, whereas those of IEL did not change significantly. The percentage of PEC NK1.1 and gamma delta T cells peaked at day 4 PI (p < 0.0001), and CD4 and CD8 alpha T cells increased continuously after infection. The percentages of IEL CD8 alpha and gamma delta T cells decreased slightly at first, and then increased. CD4 and NK1.1 T cells of IEL did not change significantly after infection. IFN-gamma-producing PEC NK1.1 T cells increased significantly from day 1 PI, but the other T cell subsets produced IFN-gamma abundantly thereafter. The proportion of IEL IFN-gamma-producing CD8 alpha and gamma delta T cells increased significantly after infection, while IEL NK1.1 T cells had similar IFN-gamma production patterns. Taken together, CD4 T cells were the major phenotype and the important IFN-gamma-producing T cell subsets in PEC after oral infection with T. gondii, whereas CD8 alpha T cells had these roles in IEL. These results suggest that PEC and IEL comprise different cell differentials and T cell responses, and according to infection route these factors may contribute to the different cellular immune responses.
Acute Disease ; Animals ; Ascitic Fluid/cytology/*metabolism ; Female ; Interferon Type II/*biosynthesis ; Intestinal Mucosa/cytology ; Lymphocytes/*metabolism ; Mice ; Mice, Inbred C57BL ; Support, Non-U.S. Gov't ; T-Lymphocyte Subsets/*immunology ; Toxoplasmosis/*immunology

A novel Pleurotus nebrodensis polysaccharide (PN-S) was purified and characterized, and its immune-stimulating activity was evaluated in RAW264.7 macrophages. PN-S induced the proliferation of RAW264.7 cells in a dose-dependent manner, as determined by the MTT assay. After exposure to PN-S, the phagocytosis of the macrophages was significantly improved, with remarkable changes in morphology being observed. Flow cytometric analysis demonstrated that PN-S promoted RAW264.7 cells to progress through S and G2/M phases. PN-S treatment enhanced the productions of interleukin-6 (IL-6), nitric oxide (NO), interferon gamma (INF-γ), and tumor necrosis factor-α (TNF-α) in the macrophages, with up-regulation of mRNA expressions of interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), interferon gamma(INF-γ) and tumor necrosis factor-α (TNF-α) being observed in a dose-dependent manner, as measured by qRT-PCR. In conclusion, these results suggest that the purified PN-S can improve immunity by activating macrophages.
Animals ; Cell Cycle ; immunology ; Cell Line ; Cell Proliferation ; drug effects ; Fungal Polysaccharides ; pharmacology ; Immunity ; drug effects ; Interferon-gamma ; biosynthesis ; metabolism ; Interleukin-6 ; biosynthesis ; metabolism ; Macrophages ; immunology ; metabolism ; Mice ; Nitric Oxide ; biosynthesis ; Nitric Oxide Synthase Type II ; metabolism ; Pleurotus ; RNA, Messenger ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Necrosis Factor-alpha ; biosynthesis ; metabolism ; Up-Regulation

To evaluate the role of nitric oxide (NO) in IFN-gamma production and apoptosis of splenocytes in genetically different strains of mice with toxoplasmosis, BALB/c (a toxoplasmosis resistant strain) and C57BL/6 (a toxoplasmosis susceptible strain) mice were infected with Toxoplasma gondii cysts orally and subsequently injected intraperitoneally with aminoguanidine, an iNOS inhibitor (AG; 35 mg/kg per mouse daily for 14 days). When BALB/c or C57BL/6 mice were infected with T. gondii without AG treatment, number of brain cysts, NO and IFN-gamma production by splenocytes, and percentages of apoptotic splenocytes were increased compared to uninfected control mice without AG treatment. AG treatment increased the number of brain cysts, and reduced NO and IFN-gamma production in T. gondii-infected C57BL/6 mice. In contrast, in T. gondii-infected BABL/c mice, the number of brain cysts, and NO and IFN-gamma production of splenocytes was not altered by treatment with AG. However, the percentages of apoptotic splenocytes in T. gondii-infected BALB/c or C57BL/6 mice were not affected by AG treatment. These results suggest that NO modulates IFN-gamma production in T. gondii-infected C57BL/6 mice, and that NO is involved in mediating a protective response in toxoplasmosis susceptible, but not resistant, mice strain during acute infection.
Animals ; Apoptosis/drug effects/*immunology ; Comparative Study ; Female ; Guanidines/*pharmacology ; Interferon Type II/*biosynthesis ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Nitric Oxide/*biosynthesis ; Nitric-Oxide Synthase/*antagonists & inhibitors ; Research Support, Non-U.S. Gov't ; Species Specificity ; Spleen/immunology ; Toxoplasmosis, Animal/*immunology