Interferon-gamma and interleukin-10 levels in serum and saliva are related to different types of oral lichen planus

Abstract BACKGROUND: Many cytokines can be detected in saliva and serum, and have more clinical significance in the diagnosis, prognosis and treatment of oral mucosa disease. OBJECTIVE: To compare the ...     

Production of interleukin-12 is under the control of endogenous interleukin-10 in myocardial ischemia-reperfusion

Interleukin (IL)-12 is a heterodimeric cytokine that is secreted mainly by antigen-presenting cells and plays a key role in determining the nature of immune response to exogenous or endogenous antigens. Negative regulators of IL-12 production include IL-10. With use of wild-type and IL-10-deficient mice, the aim of the current investigation was to determine whether IL-12 is produced in myocardial reperfusion injury and whether endogenous IL-10 modulates its production. IL-10 levels were significantly higher than baseline at both 2 h and 6 h after the start of the reperfusion. In the IL-10-deficient animals, no IL-12 could be detected in the plasma. In the wild-type animals, at baseline, and at 1-6 h after myocardial ischemia-reperfusion, no detectable increases in IL-12 were measured. However, in the IL-10-deficient mice, a significant and pronounced increase in IL-12 was detected. IL-10-deficient mice also exhibited significantly higher mortality during reperfusion than wild-type animals. We conclude that the production of IL-12 in myocardial reperfusion injury is dramatically affected by the levels of endogenous IL-10.     

Interferon-gamma inhibits macrophage apolipoprotein E production by posttranslational mechanisms.

Macrophage-derived apolipoprotein (apo) E and multimers of a synthetic apo E-peptide display monokine-like functions by inhibiting mitogen- or antigen-driven lymphocyte proliferation. This study demonstrated how the target lymphocyte itself can modulate macrophage apo E production. The lymphokine interferon-gamma (IFN) dramatically inhibited the accumulation of apo E in the supernatant of human monocytic THP-1 cells when present during phorbol myristate acetate-induced differentiation. A similar effect was observed when IFN was added to differentiated THP-1 cells. Treatment with IFN did not change the steady-state levels of apo E mRNA. Furthermore, in the presence of IFN no increased degradation or increased uptake of extracellular apo E was detected. Pulse-chase experiments indicated that IFN reduced the accumulation of extracellular apo E and increased the degradation of intracellular apo E. The inhibitory effect of IFN on apo E production also was observed in human monocyte-derived macrophages. Thus, our data demonstrated that IFN inhibited macrophage apo E production by posttranslational mechanisms. This represents a previously uncharacterized immunoregulatory interaction and lends further support to a relationship between lipid metabolism and the immune system.     

Histamine inhibits the production of interleukin-12 through interaction with H2 receptors.

IL-12 is essential for T helper 1 (Th1) development and inhibits the induction of Th2 responses. Atopic diseases, which are characterized by Th2 responses, are associated with the overproduction of histamine. Here we present evidence that histamine, at physiological concentrations, strongly inhibits human IL-12 p40 and p70 mRNA and protein production by human monocytes. The use of specific histamine receptor antagonists reveals that this inhibition is mediated via the H2 receptor and induction of intracellular cAMP. The inhibition of IL-12 production is independent of IL-10 and IFN-gamma. The observation that histamine strongly reduces the production of the Th1-inducing cytokine IL-12 implies a positive feedback mechanism for the development of Th2 responses in atopic patients.     

Interleukin-12 primes human CD4 and CD8 T cell clones for high production of both interferon-gamma and interleukin-10

Interleukin-12 (IL-12) induces differentiation of T helper 1 (Th1) cells, primarily through its ability to prime T cells for high interferon-gamma (IFN-gamma) production. We now report that the presence of IL-12 during the first several days of in vitro clonal expansion in limiting dilution cultures of polyclonally stimulated human peripheral blood CD4+ and CD8+ T cells also induces stable priming for high IL-10 production. This effect was demonstrated with T cells from both healthy donors and HIV+ patients. Priming for IL-4 production, which requires IL-4, was maximum in cultures containing both IL-12 and IL-4. IL-4 modestly inhibited the IL-12-induced priming for IFN-gamma, but almost completely suppressed the priming for IL-10 production. A proportion of the clones generated from memory CD45RO+ cells, but not those generated from naive CD45RO- CD4+ T cells, produced some combinations of IFN-gamma, IL-10, and IL-4 even in the absence of IL-12 and IL-4, suggesting in vivo cytokine priming; virtually all CD4+ clones generated from either CD45RO(-) or (+) cells, however, produced high levels of both IFN-gamma and IL-10 when IL-12 was present during expansion. These results indicate that each Th1-type (IFN-gamma) and Th2-type (IL-4 and IL-10) cytokine gene is independently regulated in human T cells and that the dichotomy between T cells with the cytokine production pattern of Th1 and Th2 cells is not due to a direct differentiation-inducing effect of immunoregulatory cytokines, but rather to secondary selective mechanisms. Particular combinations of cytokines induce a predominant generation of T cell clones with anomalous patterns of cytokine production (e.g., IFN-gamma and IL-4 or IFN-gamma and IL-10) that can also be found in a proportion of fresh peripheral blood T cells with "memory" phenotype or clones generated from them and that may identify novel Th subsets with immunoregulatory functions.     

Pancreatic islet production of murine interleukin-10 does not inhibit immune-mediated tissue destruction.

IL-10 inhibits macrophage-dependent antigen presentation, cytokine production, and generation of allospecific cells in vitro. These findings have lead to the widespread expectation that IL-10 may be a useful immunosuppressive agent to inhibit allograft rejection or autoimmunity in vivo. We used two experimental paradigms to study effects of murine IL-10 on in vivo immune responses. First, fetal pancreata or adult pancreatic islets from transgenic mice expressing IL-10 in pancreatic beta cells (Ins-IL-10 mice) were grafted across the MHC barrier to examine if IL-10 could inhibit allograft rejection. Second, Ins-IL-10 mice were crossed with transgenic mice expressing lymphocytic choriomeningitis virus (LCMV) antigens in pancreatic beta cells. These mice were infected with LCMV to elicit autoimmune diabetes, allowing us to ask if IL-10 protects islets from autoimmune destruction. We observed that allografts from IL-10-transgenic donors were rejected with comparable kinetics to the rejection of control nontransgenic allografts, indicating that IL-10 does not inhibit allograft rejection. After LCMV infection, IL-10 and LCMV antigen double transgenic mice developed diabetes earlier than LCMV antigen single transgenic littermates, suggesting that IL-10 does not inhibit islet antigen presentation or recognition. Our results contrast to in vitro observations and suggest that IL-10 cannot overcome immune-mediated tissue destruction within the pancreas.     

Interferon-alpha and interleukin-12 are induced differentially by Toll-like receptor 7 ligands in human blood dendritic cell subsets

Dendritic cells (DCs) play a crucial role in the immune responses against infections by sensing microbial invasion through toll-like receptors (TLRs). In humans, two distinct DC subsets, CD11c(-) plasmacytoid DCs (PDCs) and CD11c(+) myeloid DCs (MDCs), have been identified and can respond to different TLR ligands, depending on the differential expression of cognate TLRs. In this study, we have examined the effect of TLR-7 ligands on human DC subsets. Both subsets expressed TLR-7 and could respond to TLR-7 ligands, which enhanced the survival of the subsets and upregulated the surface expression of costimulatory molecules such as CD40, CD80, and CD86. However, the cytokine induction pattern was distinct in that PDCs and MDCs produced interferon (IFN)-alpha and interleukin (IL)-12, respectively. In response to TLR-7 ligands, the Th1 cell supporting ability of both DC subsets was enhanced, depending on the cytokines the respective subsets produced. This study demonstrates that TLR-7 exerts its biological effect in a DC subset-specific manner.     

Treatment with atorvastatin alters the ratio of interleukin-12/interleukin-10 gene expression [corrected

BACKGROUND: Statins have been shown to have pleiotropic effects extending beyond their ability to lower cholesterol. MATERIAL AND METHODS: Seventeen patients with heterozygous familial hypercholesterolaemia participated in a single-blind placebo controlled study. The patients underwent three treatment regimens: placebo (4 weeks), atorvastatin 10 mg day(-1) (4 weeks) and atorvastatin 40 mg day(-1) (12 weeks). Following each treatment period, serum lipids and plasma mevalonic acid were measured, mononuclear leukocytes were isolated and total RNA was prepared. The content of mRNA for IL-12p35 and IL-10 was assayed, blinded, by real-time quantitative polymerase chain reactions. RESULTS: Treatment of the subjects with atorvastatin decreased the abundance of IL-12p35 mRNA in mononuclear cells, but did not alter that of IL-10, so that the ratio of the IL-12p35 to IL-10 mRNA content was significantly reduced (P < 0.0026). The IL-12p35/IL-10 ratio correlated significantly with plasma mevalonic acid concentrations but not with serum LDL concentrations. CONCLUSIONS: This study provides evidence that atorvastatin exerts an immunomodulatory effect in vivo, characterized by a decrease in the ratio of IL-12 mRNA to IL-10 mRNA in leukocytes. The immunomodulatory effect of statins, in addition to their cholesterol-lowering properties, may contribute to the rapid cardiovascular benefit observed during treatment with statins and reduced the rate of rejection in patients with solid organ transplantation.     

Anti-oxidants reverse uraemia-induced down-regulation of mitochondrial membrane potential and interleukin-10 production

BACKGROUND: The anti-inflammatory cytokine, interleukin-10 (IL-10), has potent immunomodulatory effects. We hypothesized that previously reported defective synthesis of IL-10 by immunocompetent cells exposed to a uraemic milieu may be due to impaired mitochondrial membrane potential (MMP). MATERIALS AND METHODS: The human promonocytic THP-1 cell line was differentiated to monocytes and incubated with pooled control or uraemic plasma with and without catalase or N-acetyl L-cysteine (NAC). Basal hydrogen peroxide (H(2)O(2)) production was measured by flow cytometry. To measure MMP, cells were stained with rhodamine 123 (Rh123) and the uptake of Rh123 assessed by flow cytometry. To assess the relative contribution of the NADPH oxidase and mitochondrial electron transport chain (ELT) to endotoxin (ET)-stimulated IL-10 production among monocytic cells, cells were incubated with and without a selective NADPH oxidase inhibitor, apocynin and mitochondrial ELT inhibitors, diphenyliodinium and rotenone, washed and ET-stimulated IL-10 production was measured. In other experiments, cells were incubated with pooled control or uraemic plasma in the presence or absence of antioxidants followed by overnight incubation with ET. IL-10 production by monocytes in the cell supernatant was then quantified. RESULTS: Basal H(2)O(2) production was significantly higher among differentiated THP-1 cells exposed to uraemic plasma compared with normal plasma (180.57 +/- 10.24 vs. 41.57 +/- 8.98 MCI; P = 0.02). Uraemic plasma also down regulated MMP (4.60 +/- 1.28 vs. 8.00 +/- 1.59 MCI with normal plasma; P = 0.03). Both diphenyliodinium and rotenone, selective inhibitors of the mitochondrial ELT, inhibited ET-stimulated IL-10 production. In contrast, apocynin, a selective NADPH oxidase inhibitor, did not inhibit ET-stimulated IL-10 production. Further, ET-stimulated IL-10 production by cells incubated with uraemic plasma was significantly lower when compared to cells exposed to normal plasma. Pre-incubation with catalase and NAC restored uraemia-induced down regulation of MMP. In addition, ET-stimulated IL-10 production by cells incubated with uraemic plasma was also restored by both catalase and NAC. CONCLUSIONS: Our observations suggest that ET-stimulated IL-10 synthesis by monocytic cells is mitochondrial ELT-dependent and NADPH oxidase-independent. Monocytic cells exposed to a uraemic environment exhibit higher basal ROS production, lower MMP, and impaired ET-stimulated IL-10 synthesis. Anti-oxidants restore MMP and up-regulate ET-stimulated IL-10 synthesis.     

Differential effects of in vitro and in vivo hyperthermia on the production of interleukin-10

OBJECTIVE: To determine whether hyperthermia activates an anti-inflammatory response. DESIGN: A prospective study. SETTING: Heatstroke Center, Makkah, and King Faisal Specialist Hospital, Riyadh, Saudi Arabia. PATIENTS: Twenty-five heatstroke patients pre-cooling (rectal temperature 42.4 +/- 0.8 degrees C) (group 1) and 13 normothermic heat-stressed subjects were studied (group 2). Twelve of the 25 heatstroke patients were also studied post-cooling (group 3). Mononuclear cells from six healthy blood donors resting at 24 degrees C were used for in vitro study. INTERVENTIONS: Mononuclear cells were cultured at a concentration of 1 x 10(6)/ml without and with lipopolysaccharide (LPS) added at concentration of 10, 100, and 1000 ng/ml. The cells were incubated for 24 h at 37, 39, 41, and 43 degrees C. ELISA was used to measure IL-10 in the supernatant and plasma from heatstroke and heat-stressed subjects. RESULTS: All patients in group 1, 40% of group 2, and 37% of group 3, showed elevation of IL-10 (1289 +/- 2519, 248 +/- 393, and 172 +/- 226 pg/ml, respectively) compared with normal control levels, (< 100 pg/ml) P < 0.05. IL-10 level on admission did not correlate with degree of hyperthermia. During 24 h incubation at 37 degrees C without LPS, no IL-10 was detected, whereas with 10 ng/ml LPS, monocytes released 658 +/- 291 pg IL-10/10(6) cells. At 39 degrees C and 41 degrees C IL-10 release was decreased to 225 +/- 114, and 245 +/- 90 pg/10(6) cells, respectively; and was completely inhibited at 43 degrees C (67 +/- 10 pg/10(6) cells), P < 0.0001. CONCLUSION: Heat-stress with and without hyperthermia is associated with anti-inflammatory response in vivo. However, it does not seem to be the direct effect of heat on monocytes, suggesting that other environmental or genetic factors may be involved.     

High interleukin-10 production in first-degree relatives of patients with generalized but not cutaneous lupus erythematosus.

BACKGROUND: Preclinical research suggests that interleukin-10 (IL-10) is associated with susceptibility to and severity of systemic lupus erythematosus. Chronic cutaneous lupus erythematosus is thought to be immunogenetically different from systemic lupus erythematosus. We hypothesized that high innate production of IL-10 underlies systemic but not chronic cutaneous lupus erythematosus. METHODS: IL-10 production was determined after endotoxin stimulation of whole-blood samples. In whole-blood samples, disease activity and medication influence the IL-10 production in patients. Therefore, healthy first-degree relatives of patients were evaluated. One hundred sixty-six first-degree relatives of patients with systemic lupus, 50 first-degree relatives of patients with chronic cutaneous lupus, and 133 control persons were studied. Innate IL-10 production of the patient was estimated as the mean IL-10 production of the unaffected relatives. Polymorphisms located -1082, -819, and -592 base pairs relative to the IL-10 gene were typed by allele-specific oligohybridization of polymerase chain reaction-amplified DNA fragments. RESULTS: IL-10 production was higher in the families of patients with systemic lupus than in the control families (1517 +/- 94 vs 1180 +/- 59 pg/mL; P = 0.003). IL-10 production in the families of patients with chronic cutaneous lupus was similar to that in control families (1216 +/- 82 vs 1180 +/- 59 pg/ml; P = 0.74). IL-10 production was also similar in families of patients with severe compared with nonsevere systemic lupus (P = 1.0). The frequency of -1082/-819/-592 haplotypes GCC, ACC, and ATA was similar among patients and compared with the control persons (P = 0.29). CONCLUSIONS: High innate IL-10 production underlies susceptibility for systemic lupus erythematosus but not the severity of the disease. It is not related to chronic cutaneous lupus erythematosus.     

Interferon-gamma and bacterial lipopolysaccharide act synergistically on human neutrophils enhancing interleukin-8, interleukin-1beta, tumor necrosis factor-alpha, and interleukin-12 p70 secretion and phagocytosis via upregulation of toll-like receptor 4

In human neutrophils, interferon (IFN)-gamma enhanced the expression of toll-like receptor 4 (TLR4), a crucial component of the signaling receptor complex for bacterial lipopolysaccharide (LPS). Lipopolysaccharide alone did not affect TLR4 expression, but costimulation with IFN-gamma and LPS induced higher levels of TLR4 expression than stimulation with IFN-gamma alone. Using the protein synthesis inhibitor cycloheximide and measuring the expression of CD35 in neutrophils stimulated with IFN-gamma and LPS alone or in combination, we could demonstrate that IFN-gamma enhances TLR4 by de novo protein synthesis, whereas the addition of LPS acts synergistically by enhancing vesicular mobilization to the cell surface. Costimulation with IFN-gamma and LPS induced neutrophil activation and enhanced secretion of the cytokines, interleukin (IL)-8, IL-1beta, tumor necrosis factor-alpha, and IL-12 p70, and phagocytosis of latex beads, processes that were blocked by a monoclonal antibody specific for TLR4. These data suggest that IFN-gamma primes neutrophils to respond to LPS.     

Influence of interleukin-10 polymorphisms on interleukin-10 expression and survival in critically ill patients

OBJECTIVE: To determine the functionality of identified polymorphisms in the promoter and upstream regions of the interleukin-10 gene in terms of release of interleukin-10 from lipopolysaccharide-stimulated whole blood from healthy volunteers and to evaluate the relationship of interleukin-10 polymorphisms to interleukin-10 release, development of sepsis, and mortality in critically ill patients. DESIGN: Observational study. SETTING: The academic unit of anesthesia and intensive care, university laboratories, and ten-bed general intensive care unit in a university teaching hospital. SUBJECTS: A total of 132 healthy volunteers plus 67 consecutive critically ill patients recruited within 24 hrs of admission to the intensive care unit, regardless of diagnosis. MEASUREMENTS: Plasma interleukin-10 levels were measured by enzyme-linked immunosorbent assay. Single nucleotide polymorphisms were detected by restriction fragment length polymorphism analysis. Dinucleotide repeat polymorphisms were identified after polymerase chain reaction using a DNA size analyzer. MAIN RESULTS: Stimulated interleukin-10 release in critically ill patients was significantly lower than in healthy subjects (p < .0001). In addition, in the patients who developed sepsis, interleukin-10 release at admission to the intensive care unit was significantly lower than in patients who did not subsequently develop sepsis (median [range] 1.47 [0.13-6.90] ng/mL compared with 4.93 [0.03-16.80] ng/mL, p = .001). The A allele of the single nucleotide polymorphism at -592 base pairs was associated with lower interleukin-10 release and higher mortality in critically ill patients. Other polymorphisms were not linked to interleukin-10 release, sepsis, or mortality. CONCLUSIONS: The A allele of the -592 base pair single nucleotide polymorphism in the interleukin-10 gene is associated with lower stimulated interleukin-10 release and increased mortality. Further investigations are required to determine the nature of the functionality and the potential diagnostic and therapeutic aspects of this marker.     

Changes in interleukin-2 and interleukin-4 production in asymptomatic, human immunodeficiency virus-seropositive individuals.

Infection with HIV results in an incremental loss of T helper cell (TH) function, which can occur years before CD4 cell numbers are critically reduced and AIDS is diagnosed. All TH function is not affected, however, because B cell activation and hypergammaglobulinema are also characteristic of this period. Recently, in a murine model of AIDS an early loss in production of the CD4 cytokines IL-2 and IFN-gamma was correlated with an increase in the B cell stimulatory cytokines IL-4, IL-5, and IL-10. We therefore assessed the production of IL-4 generated by PBL from HIV-seropositive (HIV+) individuals who did not have AIDS, yet who exhibited different TH functional categories based on their IL-2 production profiles. We observed that the decreases in recall antigen-stimulated IL-2 production were accompanied by an increase in IL-4 production. The loss of recall antigen-stimulated responses in HIV+ individuals could be reversed in vitro by anti-IL-4 antibody. Our results suggest that the TH functions assessed by IL-4 production replace the normally dominant TH function of antigen-stimulated IL-2 production in the progression toward AIDS, and raise the possibility of cytokine cross-regulation in AIDS therapy.     

Immune complexes inhibit antimicrobial responses through interleukin-10 production. Effects in severe combined immunodeficient mice during Listeria infection.

The presence of soluble antigen-antibody complexes renders mice highly susceptible to infection with the intracellular pathogen Listeria monocytogenes. In this report we show that this inhibition is manifest at the level of the innate immune response and is mediated by IL-10. Like immuno-competent mice, mice with the severe combined immunodeficient mutation (SCID) injected with immune complexes died from a sublethal dose of L. monocytogenes. These mice were protected if pretreated with neutralizing antibodies to IL-10. In vitro, immune complexes stimulated IL-10 production by SCID splenocytes and splenic macrophages. Likewise, immune complexes inhibited TNF and IFN-gamma production by SCID splenocytes cultured with heat-killed-L. monocytogenes. This inhibition was reversed by neutralization of IL-10 but not IL-4 or TGF-beta. Immune complexes and rIL-10 inhibited cytokine production by SCID splenocytes if added before or simultaneously with heat-killed-L. monocytogenes. These data support a model in which immune complexes modulate host defense and the immune response by stimulating the production of IL-10 from macrophages.     

Defective gamma interferon production in leprosy. Reversal with antigen and interleukin 2

Antigen and mitogen-induced gamma interferon (gamma-IFN) production was studied in peripheral blood mononuclear cells from 34 leprosy patients. 17 of 18 lepromatous leprosy and borderline lepromatous patients (LL and BL) failed to release gamma-IFN in response to specific antigen (Mycobacterium leprae) and displayed reduced responses to mitogen (concanavalin A) stimulation. In contrast, cells from six tuberculoid and borderline tuberculoid patients (TT and BT) produced considerable levels of gamma-IFN under the same experimental conditions. Normal controls failed to respond to M. leprae and most displayed good responses to concanavalin A. Mid-borderline patients (BB) showed intermediate levels of gamma-IFN release. gamma-IFN release by lepromatous patients could be partially restored with purified interleukin 2 and M. leprae antigen but not with interleukin 2 alone.     

Interferon-gamma production closely related to antibody production in lymphocyte cultures stimulated with mumps virus

Enzyme-linked immunosorbent assay (ELISA) antibody to mumps virus and virus specific interferon (IFN)-gamma production were investigated in lymphocyte cultures stimulated with mumps virus before and after immunization with live mumps vaccine. Synthesis of immunoglobulin (Ig) M but not Ig G was enhanced after vaccination. Spontaneous production of mumps ELISA antibodies in lymphocyte culture increased after vaccination and substantially higher levels of antibodies were produced when lymphocytes were stimulated with mumps virus after vaccination. The production of mumps ELISA antibodies was closely related to IFN-gamma production (r = 0.326, p less than 0.01) but not to IFN-alpha production (r = 0.084, p greater than 0.05).