Cytokine Synthesis Inhibitory Factor Research Articles

Cytokine Profile Following Varnimcabtagene Autoleucel (IMN-003A) in Patients with Relapsed Refractory B Cell Malignancies in the First-in-India Industry Phase-2 Study (IMAGINE)

Background: Varnimcabtagene autoleucel (Var-cel, IMN-003A) is an autologous CD19 directed CAR-T cell product with a 4-1BB co-stimulatory domain and a non-FMC63 murine single chain variable fragment (A3B1 binder), manufactured in India, tested in the IMAGINE study (CTRI/2022/03/041162), a phase-2 clinical trial for patients (pts) with relapsed and/or refractory B cell malignancies. This abstract evaluates the cytokine profile and its correlation with safety outcomes and CAR-T expansion following var-cel infusion. Methods: Serum was collected pre-infusion and upto 13 timepoints post infusion as per study schedule for evaluating cytokine levels. Nine cytokines (IFN-g, TNF-α, IL-1β, IL-2, IL-7, IL-8, IL-10, IL-15 and MCP-1) were measured using a multiplexed kit on the Magpix platform. IL-6 level was measured using electrochemiluminescence immunoassay (ECLIA). Safety and adverse event data were collected for analysis along with measuring various cytokine levels in the serum. CAR-T persistence post infusion was monitored using ddPCR. Results: 24 patients (pts) were infused with var-cel in the IMAGINE study. Var-cel levels in peripheral blood post-infusion were measured at multiple timepoints for all infused pts using ddPCR platform. The var-cel levels peaked (Tmax) at a median of 10 days post infusion (D+10; range: 10 - 28 days) with median Cmax of 125,242 (range 18,256 - 413,968 copies/µg genomic DNA). The median duration of persistence was 56 days with persistent CAR seen in 3 pts at last follow-up. Adverse events of special interest (AESIs) reported were CRS (Grade [G] 1 62.5%; G3+ 4.2%; overall 66.7%) and ICANS (G1 4.2%; G3+ 0%; overall 4.2%). The median onset of CRS at D+5, 5 days before the median var-cel Tmax of D+10. The median duration for CRS was 3 days. No G3+ ICANS was reported. Serum IL-6 levels peaked at a median of D+7 post infusion and reached above 40 pg/mL for 13 pts, all of whom experienced CRS. All eight pts with no CRS had peak IL-6 levels below 40 pg/mL. Despite this significant association with CRS (p<0.001, Man-Whitney test) and published causation, IL-6 level peaked towards the end of clinical course of CRS manifestation, but usually at or before peak var-cel expansion (Tmax). Interestingly, the increase in IL-6 levels tended to begin early and persist longer for some B-NHL patients compared to B-ALL patients. Preliminary multiplexed cytokine analysis for evaluated pts (n=6) indicated that IFN-γ, TNF-α, IL-1β, IL-2, IL-7, IL-8 remained within published physiological limits for most patients at all timepoints (except one pt with highest levels at screening). One patient showed mild increase in IFN-γ (peak 50.88 pg/mL) and two pts showed mild increase in IL-8 around D+4 to D+7 (peak 47.71 pg/mL). IL-15 and MCP-1 levels were relatively higher (>2 fold) from D0 to D+7 post infusion, compared to the screening timepoint, consistent with the duration of CRS. Only IL-10, an anti-inflammatory and cytokine synthesis inhibitory factor stood out having a sharp peak (median: 230 pg/mL) for all six patients at D+4 to D+10, consistent with the timeline for end of CRS and before var-cel Tmax. Occasional pt with no clinical CRS also showed IL-10 peak. Updated cytokine profile data shall be presented at the meeting. Conclusions: This is the first-in-India industry study evaluating cytokine profile at multiple timepoints before and after var-cel infusion and its correlation with clinical CRS. As per published literature, IL-6 levels were significantly associated with clinical CRS and showed association with peak var-cel expansion. There was a sharp increase in both IL-6 and IL-10 levels in serum post infusion, concurrent with clinical CRS prior to peak var-cel expansion. A further detailed study of cytokine profile following var-cel infusion shall help prognosticate safety outcomes.

The mechanisms related to fibroblasts in burn surface.

Mesenchymal stem cells (MSCs) can promote burn wound healing, skin appearance, and function recovery by promoting the differentiation and migration of fibroblasts of a wound. The burn environment can activate the autophagy of MSCs. However, it is not clear whether this autophagy can affect the proliferation and migration of fibroblasts. In this study, pretreated MSCs with rapamycin and 3-methyladenine modulated autophagy and co-cultured with fibroblasts of burn. Cell migration was detected by immunofluorescence chemical staining. Western blot analysis and enzyme-linked immunosorbent assay were performed to detect 2,3-Dioxygenase (IDO), cytokine synthesis inhibitory factor 10 (IL-10), cytokine synthesis inhibitory factor 6 (IL-6), prostaglandin E2 (PGE2), transforming growth factor beta 1 (TGF-β1) proteins levels, and the autophagy proteins p62 and microtubule-associated protein LC3-II/I. We demonstrated that autophagy regulates MSCs survival and proliferation in burn wound transplants and found that autophagy inhibition with 3-methyladenine reduced MSCs-mediated, fibroblast proliferation and migration in burn environment. However, rapamycin-induced autophagy had the opposite effect and increased the TGF-β1 expression. Therefore, we speculate that MSCs may promote fibroblast proliferation and migration by secreting TGF-β1 via the AKT/mTOR (RAC-alpha serine/threonine-protein kinase/mammalian target of rapamycin) pathway. Autophagy of MSCs regulates burn wound fibroblast proliferation and migration by affecting TGF-β1 and prostaglandin E2 production adjacent to MSCs transplanted on the burn wound. The results of this study provide a potential strategy for promoting MSCs treatment of burns.

Evaluation of some biochemical markers in relation to COVID-19 mRNA vaccine

Background The coronavirus disease 2019 (COVID-19) has become a national pandemic for more than 2 years, and it continues to have an unimaginable impact on our way of life and quality of life. It is critical to gain a deeper understanding of how immunity is regulated in response to SARS-CoV-2 infection. The C-reactive.protein.(CRP) was the first acute phase protein to be identified, and it serves as a highly sensitive systemic indication of tissue damage, infection, as well as inflammation. Smooth muscle cells, lymphocytes, macrophages, endothelial cells, and adipocytes are all involved in the production of this protein. Interleukin.10.(IL-10), commonly described as human. cytokine.synthesis.inhibitory.factor (CSIF). The IL-10 gene in humans produces interleukin 10, a pleiotropic cytokine with strong anti-inflammatory as well as immunosuppressive activities. The Aim the aim of this study is to evaluate the vaccine effectiveness using diagnostic biochemical markers. Material and method this study included 125 patients (56 males and 69 females) with vaccinated and non-vaccinated COVID-19 with an age range of 20–70 years. These patients are divided into two main groups: 1. vaccinated (vaccinated with COVID-19 infection, vaccinated without COVID-19 disease, vaccinated recoveredfrom the CoV-19 virus), 2. Unvaccinated (infected with the CoV-19 virus and non-vaccinated, recovered from COVID-19 and unvaccinated). The outcome is measured using the enzyme-linked immunosorbent assay (ELISA) technique. This study was conducted during the period from November 2021 to May 2022 at Al-Shifaa medical center and the vaccine unit at Al-Diwaniyah Educational Hospital, Diwaniyah governorate, Iraq. Results The results showed an increase in CRP level for the vaccinated groups was significantly higher (P<0.0001) in group G2 (vaccinated with COVID) more than in G1 (vaccinated without COVID) and G3 (vaccinated recovered COVID). For non-vaccinated groups, it was significantly higher (P<0.01) in group G4 (no vaccine with COVID) more than in group G5 (no vaccine recovered COVID). The results also showed that the IL-10 in the 2nd and 4th weeks after vaccination had a higher level in G1 (vaccinated without COVID) and G2 (vaccinated with COVID) than in any other time incident. For G4 (no vaccine with COVID) showed that a significant increase was noticed in the 2nd week after diagnosis more than other time incidents. While G3 (vaccinated recovered COVID), G5 (no vaccine recovered COVID) showed that no significant increase was noticed among the different time incidents. Conclusion the use of mRNA for CoV-19 vaccination significantly modulates the increment of C-reactive protein and interleukin-10 and improves the immune response in patients with COVID-19 infection.

IL-10: A Paradigm for Counterregulatory Cytokines.

![][1] Interleukin-10 was first discovered in 1989 as cytokine synthesis inhibitory factor produced by CD4+ Th2 clones in response to the lectin Con A or Ag stimulation ([1][2]). At this time, increasing evidence suggested that Th1 and Th2 subsets possessed reciprocal inhibitory functions

Interleukin-10 Gene Polymorphisms in Recurrent Aphthous Stomatitis

Recurrent aphthous stomatitis (RAS) is a common oral inflammatory disease with unknown etiology in which the immune system seems to have a role in oral tolerance. Interleukin (IL)-10 is a cytokine synthesis inhibitory factor. Single nucleotide polymorphisms (SNPs) of IL10 gene could alter this cytokine production. The aim of this study was to investigate frequencies of IL10 alleles and genotypes in a group of individuals with RAS. Genomic DNA of 60 Iranian patients with RAS were typed for IL10 gene (C/A −1082, C/T −819, and C/A −592), using PCR-SSP method. Frequency of each allele and genotype was compared to control group.A significantly higher frequencies of the T allele at position −819 (p = 0.006) and the A allele at position of −592 (p < 0.001) were found in the patients with RAS group, when compared to the controls. IL10 GA genotype at position −1082 (p = 0.007), CA genotype at position −592 (p = 0.001), and CT genotype at position −819 (p = 0.001) were significantly higher in the RAS patients. The results of this study suggest that certain SNPs of IL10 gene have association with predisposition of individuals to RAS. However, further multicenter studies should be conducted to confirm the results of this study.

Expression of inhibitory markers is increased on effector memory T cells during hepatitis C virus/HIV coinfection as compared to hepatitis C virus or HIV monoinfection

Hepatitis C virus (HCV)/HIV coinfection is associated with rapid progression of hepatic fibrosis and liver disease. T-cell response has been implicated in the pathophysiological outcome of the disease. This study sought to evaluate the role of memory T-cell exhaustion in enhancing immune dysfunction during coinfection. Sixty-four patients were included in the study; HCV monoinfected (n = 21), HIV monoinfected (n = 23), HCV/HIV coinfected (n = 20), and healthy controls (n = 20). Peripheral blood mononuclear cells (PBMCs) were isolated; immunophenotyped and functional assays were performed. A significant increase in the naive T cells and central memory T cells and a marked reduction in effector memory T cells (TEM) were observed with coinfection as compared to monoinfection. Inhibitory markers programmed death 1 (PD-1) and T-cell immunoglobulin and mucin domain containing molecule 3 (TIM3) were highly upregulated on TEM in coinfection and functionally, these TEM cells displayed lowered proliferation. Increased expression of PD-1 and TIM3 correlated with decreased levels of CD8+CD107a+ TEM cells in coinfection. Pro-inflammatory cytokines interferon-γ and interleukin-2 (IL-2) secretion by TEM cells were also reduced during chronic viral infection. Secretion of IL-10, a human cytokine synthesis inhibitory factor, was significantly upregulated in CD4 TEM with HCV/HIV coinfection in comparison to HCV monoinfection. TEM cells play an important role during viral infection and enhanced expression of inhibitory markers is associated with decreased proliferation and cytotoxicity and increased IL-10 production, which was pronounced in HCV/HIV coinfection. Thus, decreased TEM functionality contributes to diminished host immune responses during HCV/HIV coinfection as compared to HCV or HIV monoinfection.

Abstract 481: Athero-metabolic and Inflammatory Alterations Promote In-stent Restenosis in ApolipoproteinE Deficient Rats

Purpose Recently, Apoliprotein E deficient (ApoE-/-) rats have been generated by genetic manipulation, while the bench-to-bedside relevance of this novel model for coronary stenosis research has not been elucidated. Here, we seek to characterize vascular inflammation and in-stent cross-sectional stenosis (ICS) development in the abdominal aorta of ApoE-/- rats. Methods Trans-abdominal aorta bare-metal stent (Multi-LinkMini Vision, Abbott Vascular Inc., Santa Clara, CA; 2.5 x 8 mm; 12 atm) implantation was performed in ApoE-/- rats (Sigma Aldrich Genetic Engineering, Saint Louis, MO). At 7 and 28 days, quantification of ICS, neointimal (NI) area, injury score and inflammation score was conducted using image analysis software (DISKUS, Hilgers, Königswinter). Blood serum analysis for Interleukin (IL)-6, -8 and -10 and for cholesterol levels was performed. Results Serum cholesterol levels were elevated in ApoE-/- rats (8.63±1.73mmol/l vs. 1.98±0.55mmol/l; p&lt;0.001) as compared to ApoE+/+ rats. IL-6 and (294.7±80.2pg/ml vs. 187.2±2.8pg/ml; p&lt;0.05) and IL-8/CXCL8 (767.5±127.5pg/ml vs. 342.0±39.7pg/ml; p&lt;0.05) were upregulated, while IL-10/cytokine-synthesis inhibitory factor was downregulated (16.8±1.4pg/ml vs. 90.7±6.5pg/ml; p&lt;0.001) in ApoE-/- rats. After stent implantation, injury scores were similar in all groups. At 7 days, ICS (11.1±1.9% vs. 2.1±0.5%; p&lt;0.01) and NI area (0.59±0.09mm2 vs. 0.075±0.02mm2; p&lt;0.01) was increased as compared to controls; concomitantly, at 28 days, ICS (26.6±3.9% vs. 13.1±1.9%; p&lt;0.001) and NI area (1.47±0.37mm2 vs. 0.54±0.10mm2; p&lt;0.01) were elevated. Furthermore, infiltration by chronic inflammatory cells was increased in ApoE-/- rats at 28 days (456.2±181.4 vs. 108.0±25.9 per high power field; p&lt;0.05). Conclusions In ApoE-/- rats, cholesterol levels as well as pro-inflammatory IL-6 and -8 are upregulated, while anti-inflammatory IL-10 is downregulated. Concomitantly, ApoE-/- rats develop increased ICS after abdominal stent implantation. This novel small animal model enables the characterization of distinctive molecular and mechanical ICS mechanisms in an atherogenic milieu that, notably, renders disposable any miniaturization of tested stents as opposed to mouse models.

Herpesviruses and the microbiome

The focus of this article will be to examine the role of common herpesviruses as a component of the microbiome of atopic patients and to review clinical observations suggesting that atopic patients might be predisposed to more severe and atypical herpes-related illness because their immune response is biased toward a TH2 cytokine profile. Human populations are infected with 8 herpesviruses, including herpes simplex virus HSV1 and HSV2 (also termed HHV1 and HHV2), varicella zoster virus (VZV or HHV3), EBV (HHV4), cytomegalovirus (HHV5), HHV6, HHV7, and Kaposi sarcoma-associated herpesvirus (termed KSV or HHV8). Herpesviruses are highly adapted to lifelong infection of their human hosts and thus can be considered a component of the human "microbiome" in addition to their role in illness triggered by primary infection. HSV1 and HSV2 infection and reactivation can present with more severe cutaneous symptoms termed eczema herpeticum in the atopic population, similar to the more severe eczema vaccinatum, and drug reaction with eosinophilia and systemic symptoms syndrome (DRESS) is associated with reactivation of HSV6 and possibly other herpesviruses in both atopic and nonatopic patients. In this review evidence is reviewed that primary infection with herpesviruses may have an atypical presentation in the atopic patient and conversely that childhood infection might alter the atopic phenotype. Reactivation of latent herpesviruses can directly alter host cytokine profiles through viral expression of cytokine-like proteins, such as IL-10 (EBV) or IL-6 (cytomegalovirus and HHV8), viral encoded and secreted siRNA and microRNAs, and modulation of expression of host transcription pathways, such as nuclear factor κB. Physicians caring for allergic and atopic populations should be aware of common and uncommon presentations of herpes-related disease in atopic patients to provide accurate diagnosis and avoid unnecessary laboratory testing or incorrect diagnosis of other conditions, such as drug allergy or autoimmune disease. Antiviral therapy and vaccines should be administered promptly when indicated clinically.

Pro-Inflammatory Signaling by IL-10 and IL-22: Bad Habit Stirred Up by Interferons?

Interleukin (IL)-10 and IL-22 are key members of the IL-10 cytokine family that share characteristic properties such as defined structural features, usage of IL-10R2 as one receptor chain, and activation of signal transducer and activator of transcription (STAT)-3 as dominant signaling mode. IL-10, formerly known as cytokine synthesis inhibitory factor, is key to deactivation of monocytes/macrophages and dendritic cells. Accordingly, pre-clinical studies document its anti-inflammatory capacity. However, the outcome of clinical trials assessing the therapeutic potential of IL-10 in prototypic inflammatory disorders has been disappointing. In contrast to IL-10, IL-22 acts primarily on non-leukocytic cells, in particular epithelial cells of intestine, skin, liver, and lung. STAT3-driven proliferation, anti-apoptosis, and anti-microbial tissue protection is regarded a principal function of IL-22 at host/environment interfaces. In this hypothesis article, hidden/underappreciated pro-inflammatory characteristics of IL-10 and IL-22 are outlined and related to cellular priming by type I interferon. It is tempting to speculate that an inherent inflammatory potential of IL-10 and IL-22 confines their usage in tissue protective therapy and beyond that determines in some patients efficacy of type I interferon treatment.

Interleukin 10 knockout frail mice develop cardiac and vascular dysfunction with increased age

Cardiovascular dysfunction is a primary independent predictor of age-related morbidity and mortality. Frailty is associated with activation of inflammatory pathways and fatigue that commonly presents and progresses with age. Interleukin 10 (IL-10), the cytokine synthesis inhibitory factor, is an anti-inflammatory cytokine produced by immune and non-immune cells. Homozygous deletion of IL-10 in mice yields a phenotype that is consistent with human frailty, including age-related increases in serum inflammatory mediators, muscular weakness, higher levels of IGF-1 at midlife, and early mortality. While emerging evidence suggests a role for IL-10 in vascular protection, a clear mechanism has not yet been elucidated. MethodsIn order to evaluate the role of IL-10 in maintenance of vascular function, force tension myography was utilized to access ex-vivo endothelium dependent vasorelaxation in vessels isolated from IL-10 knockout IL-10(tm/tm) and control mice. Pulse wave velocity ((PWV), index of stiffness) of vasculature was measured using ultrasound and blood pressure was measured using the tail cuff method. Echocardiography was used to elucidated structure and functional changes in the heart. ResultsMean arterial pressures were significantly higher in IL-10(tm/tm) mice as compared to C57BL6/wild type (WT) controls. PWV was increased in IL-10(tm/tm) indicating stiffer vasculature. Endothelial intact aortic rings isolated from IL-10(tm/tm) mice demonstrated impaired vasodilation at low acetylcholine doses and vasoconstriction at higher doses whereas vasorelaxation responses were preserved in rings from WT mice. Cyclo-oxygenase (COX-2)/thromboxane A2 inhibitors improved endothelial dependent vasorelaxation and reversed vasoconstriction. Left ventricular end systolic diameter, left ventricular mass, isovolumic relaxation time, fractional shortening and ejection fraction were all significantly different in the aged IL-10(tm/tm) mice compared to WT mice. ConclusionAged IL-10(tm/tm) mice have stiffer vessels and decreased vascular relaxation due to an increase in eicosanoids, specifically COX-2 activity and resultant thromboxane A2 receptor activation. Our results also suggest that aging IL-10(tm/tm) mice have an increased heart size and impaired cardiac function compared to age-matched WT mice. While further studies will be necessary to determine if this age-related phenotype develops as a result of inflammatory pathway activation or lack of IL-10, it is essential for maintaining the vascular compliance and endothelial function during the aging process. Given that a similar cardiovascular phenotype is present in frail, older adults, these findings further support the utility of the IL-10(tm/tm) mouse as a model of frailty.

Systemic Delivery of IL-10 by Bone Marrow Derived Stromal Cells Has Therapeutic Benefits in Sepsis Therapy*

Sepsis is one of the most serious problems of modern medicine nowadays and improvements in treatments are urgently needed. Bone marrow derived stromal cells (BMSCs) have a potent immunosuppressive effect in humans in vivo. IL-10, a cytokine synthesis inhibitory factor, plays an important role in anti-inflammatory response. Here BMSCs were infected with recombinant adenovirus encoding murine IL-10 (mIL-10) and a GFP marker to obtain GFP positive BMSC-mIL-10 cells. The BMSC-mIL-10 cells were injected into mice with cecal ligation and puncture (CLP)-induced sepsis, and the enhanced expression of IL-10 in blood was confirmed by ELISA. Indeed, in CLP mice mode, the systematic delivery of IL-10 via BMSCs effectively suppressed the production of proinflammatory cytokines, including TNF-α, IL-6, IL-1α and IL-1β, compared to BMSCs alone. The therapeutic benefits were further demonstrated by an increased prevention from body loss, increased survival rate, and the suppression of inflammatory response in lung and kidney. Furthermore, these effects may be mediated by inhibiting the activation of NF-κB in macrophages and neutrophils. Collectively, these results suggest that systemic delivery of IL-10 by BMSCs may serve as a potential treatment in sepsis therapy.

Identification of a class of small molecules that up-regulate production of anti-inflammatory cytokine IL10 via inhibition of GSK3β (51.10)

Abstract Interleukin-10 (IL-10), also known as human cytokine synthesis inhibitory factor (CSIF), is an anti-inflammatory cytokine produced primarily by monocytes and to a lesser extent by lymphocytes. This cytokine exhibits pleiotropic effects in immunoregulation and inflammation and is capable of inhibiting synthesis of various pro-inflammatory cytokines such as IFNγ, IL-2, IL-3, IL-6, TNFα and GM-CSF made by cells such as macrophages and Th-1 cells. During the course of our investigation to find small molecules that are capable of inhibiting the production of a pro-inflammatory cytokine, IL-23, we came across a sub-set of small molecules that exhibited an interesting property of up-regulating expression of IL-10 besides inhibiting IL-23 production. Such observation prompted us to further investigate the mechanism of action and target identification for this class of compounds. Preliminary experiments revealed that enhanced IL-10 production upon LPS stimulation of human THP-1 monocytic cells in the presence of compounds appears to be due to inhibition of GSK3β kinase. Results from these studies were further substantiated by screening the lead candidate against a panel of kinases in-vitro including GSK3β and a cell-based β-cateinin accumulation assay that directly measures GSK3β kinase on-target activity.

Role of IL-10 in the resolution of airway inflammation.

IL-10 can be considered an important agent in the resolution of inflammation. Originally named "cytokine synthesis inhibitory factor" for its ability to inhibit IFN-gamma and IL-2 production in Th2 cells, it is secreted by monocytes, macrophages, mast cells, T and B lymphocytes, and dendritic cells (DCs). IL-10 production and release by monocytic cells in response to allergic challenge is upregulated by TNF-alpha, and by negative feedback regulation of itself. However, it is also secreted by T regulatory cells (Tregs), under the control of IL-2. Importantly in the context of asthma, IL-10 inhibits eosinophilia, by suppression of IL-5 and GM-CSF, by direct effects on eosinophil apoptosis, and effects on cell proliferation through down-regulation of IL-1. A number of its cytokine suppressive characteristics are now thought to occur through its upregulation of suppressor of cytokine signaling (SOCS)-3. IL-10 is also a suppressor of nitric oxide (NO) production, which may have ramifications for its role in airway inflammatory diseases. Initial clinical trials have demonstrated relative safety and few clinically adverse events at doses of recombinant human IL-10 below 50 microg/kg, with mixed success in treatment of patients with inflammatory bowel disease and psoriasis. However, both steroid therapy and allergen specific immunotherapy are known to elevate endogenous IL-10 levels, which may account for their efficacy, suggesting that further study of IL-10 as a target for treatment of airway inflammatory diseases such as asthma and COPD is warranted.

Interleukin-10 containing normal human serum inhibits granzyme B release but not perforin release from alloreactive and EBV-specific T cell clones

Interleukin-10 (IL-10), also known as cytokine synthesis inhibitory factor, is capable of inhibiting synthesis of pro-inflammatory cytokines like IFNγ, IL-2, IL-3, TNFα and GM-CSF made by cells such as macrophages and T helper Type 1 cells. We observed that normal human serum, derived from a healthy individual but containing large amounts of IL-10, inhibited cytotoxic activity and interfered with granzyme B release from alloreactive cytotoxic T cell (CTL) clones in vitro, but did not affect perforin release. The addition of normal human serum containing high levels of anti-IL-10 IgG neutralized the inhibitory effects of IL-10 serum. Moreover, we have identified that cytotoxic activity and granzyme B release from an Epstein-Barr virus (EBV)-specific CTL clone was similarly inhibited in the presence of IL-10 serum, while perforin release was unaffected. Anti-IL-10 IgG serum also appeared to neutralize the inhibitory effect of IL-10 serum on an EBV-specific CTL clone.

Interleukin-10 containing normal human serum inhibits granzyme B release but not perforin release from alloreactive and EBV-specific T cell clones

AbstractInterleukin-10 (IL-10), also known as cytokine synthesis inhibitory factor, has pleiotropic effects in immunoregulation and inflammation. It is capable of inhibiting synthesis of pro-inflammatory cytokines like interferon γ (IFNγ), IL-2, IL-3, tumor necrosis factor α(TNFα) and granulocyte macrophage colony stimulating factor (GM-CSF) made by cells such as macrophages and T helper Type 1 cells. We observed that normal human serum, derived from a healthy individual but containing large amounts of IL-10 (arbitrarily designated as "IL-10 serum"), inhibited cytotoxic activity and interfered with granzyme B release from alloreactive cytotoxic T cell (CTL) clones in vitro, but did not affect perforin release. The addition of normal human serum containing high levels of anti-IL-10 IgG (arbitrarily designated as "anti-IL-10 IgG serum") neutralized the inhibitory effects of IL-10 serum. Moreover, we have identified that cytotoxic activity and granzyme B release from an Epstein-Barr virus (EBV)-specific CTL clone was similarly inhibited in the presence of IL-10 serum, while perforin release was unaffected. Anti-IL-10 IgG serum also appeared to neutralize the inhibitory effect of IL-10 serum on an EBV-specific CTL clone.

Interleukin-10 containing normal human serum inhibits granzyme B release but not perforin release from alloreactive and EBV-specific T cell clones

AbstractInterleukin-10 (IL-10), also known as cytokine synthesis inhibitory factor, has pleiotropic effects in immunoregulation and inflammation. It is capable of inhibiting synthesis of pro-inflammatory cytokines like interferon [gamma] (IFN[gamma]), IL-2, IL-3, tumor necrosis factor [alpha] (TNF[alpha]) and granulocyte macrophage colony stimulating factor (GM-CSF) made by cells such as macrophages and T helper Type 1 cells. We observed that normal human serum, derived from a healthy individual but containing large amounts of IL-10 (arbitrarily designated as "IL-10 serum"), inhibited cytotoxic activity and interfered with granzyme B release from alloreactive cytotoxic T cell clones in vitro, but did not affect perforin release. The addition of normal human serum containing high levels of anti-IL-10 IgG (arbitrarily designated as "anti-IL-10 IgG serum") neutralized the inhibitory effects of IL-10 serum. Moreover, we have identified that cytotoxic activity and granzyme B release from an Epstein-Barr virus (EBV)-specific cytotoxic T cell clone was similarly inhibited in the presence of IL-10 serum, while perforin release was unaffected. Anti-IL-10 IgG serum also appeared to neutralize the inhibitory effect of IL-10 serum on an EBV-specific T cell clone. When anti-IL-10 IgG was depleted from anti-IL-10 IgG containing serum (arbitrarily designated as "anti-IL10 IgG free serum"), the neutralizing effect disappeared for both alloreactive and an EBV-specific T cell clone.

Interleukin-10

Interleukin (IL)-10, initially described as cytokine synthesis inhibitory factor, is a pleotropic cytokine produced by many cell populations. Its main biological functions appear to be quite diverse: on the one hand it is involved in the limitation and termination of inflammatory responses and the regulation of differentiation and proliferation of several immune cells, and on the other hand it mediates immunostimulatory properties that support the elimination of infectious and non-infectious particles with limited inflammation. Numerous investigations, including expression analyses in patients, and both in vitro and in vivo studies suggest a major physiological and pathophysiological impact of IL-10. Activation of the neuro-endocrine axis following acute stress reactions leads to systemic IL-10 release, preventing hyperinflammatory reactions. IL-10 is overexpressed in many solid tumors and lymphomas and considered to promote further tumor development. In contrast, a relative IL-10 deficiency has been observed and is regarded to be of pathophysiological relevance in certain inflammatory disorders characterized by a type 1 cytokine pattern such as psoriasis. Recombinant human IL-10 has been tested in several clinical trials including rheumatoid arthritis, inflammatory bowel disease, psoriasis, organ transplantation, and hepatitis C. The results are heterogeneous and give new insight into the immunobiology of IL-10. However, further investigations would be desirable to better determine the effect/side effect profile as well as the best first line target indication and optimal therapeutic regimen.

The role of alpha-MSH as a modulator of cutaneous inflammation.

Among various neuropeptides such as substance P, calcitonin gene-related peptide and others, alpha-melanocyte-stimulating hormone (alpha-MSH) was found to be produced in the skin. Moreover, melanocortin receptor 1 (MC-1R), which is specific for alpha-MSH and ACTH, is expressed in the skin on keratinocytes, dendritic cells, macrophages and endothelial cells. In monocytes, macrophages and dendritic cells alpha-MSH inhibits the production and activity of immunoregulatory and proinflammatory cytokines such as IL-2, IFN-gamma, TNF-alpha and IL-1. It downregulates the expression of costimulatory molecules such as CD86 and CD40 and induces the production of suppressor factors such as the cytokine synthesis inhibitory factor IL-10. On endothelial cells alpha-MSH is capable of downregulating the LPS-induced expression of adhesion molecules such as vascular cell adhesion molecule (VCAM) and E-selectin. Moreover, the LPS-induced activation of transcription factors such as NF kappa B is downregulated by alpha-MSH. In a mouse model i.v. or topical application of alpha-MSH was found to inhibit the induction phase as well as the effector phase of contact hypersensitivity (CHS) reactions and to induce hapten-specific tolerance. These findings indicate that the production of immunosuppressing neuropeptides such as alpha-MSH by epidermal cells may play an essential role during the pathogenesis of immune and inflammatory reactions in the skin.

IL-10 Inhibits Porphyromonas gingivalis LPS-Stimulated Human Gingival Fibroblasts Production of IL-6

Lipopolysaccharides (LPS) of Porphyromonas gingivalis have been implicated in the initiation and development of periodontal diseases. In a previous study, we investigated the signal transduction pathway of P. gingivalis and demonstrated that LPS stimulates the production of interleukin (IL)-6 in human gingival fibroblasts (HGFs), which in turn activates osteoclasts in vitro. The cytokine, IL-10, was initially described as cytokine synthesis inhibitory factor. In this study, we examined that effect of IL-10 on P. gingivalis LPS-induced human gingival fibroblast production of IL-6. LPS-induced IL-6 production was inhibited by IL-10 in a dose-dependent manner. Flow cytometric analysis showed that HGFs bind to fluorescein-isothiocyanate (FITC) labeled IL-10. Western blotting analysis demonstrated the expression of IL-10 receptor on the cell surface of these cells. Engagement of LPS initiated the protein tyrosine phosphorylation of several intracellular proteins including extracellular signal-regulated kinase 2 (ERK2), and these events were suppressed by IL-10. These results suggest that IL-10 inhibits the inflammatory response via the IL-10 receptor in P. gingivalis LPS-initiated periodontal diseases.

Modulation of Formyl Peptide Receptor Expression by IL-10 in Human Monocytes and Neutrophils

IL-10, originally described as a cytokine synthesis inhibitory factor, is secreted by a number of cells of the immune system, including monocytes and T cells. Although IL-10 is being assigned as an immunosuppressive cytokine, our study showed that FMLP-R mRNA was rapidly up-regulated by exposure of monocytes to graded concentrations of this cytokine, with maximal (three- to fourfold) stimulation with 10 ng/ml. The effect was rapid, being observable as early as 1 h of treatment with IL-10, maximal between 2 and 4 h, and still evident after 24 h and was associated with an increase of receptor expression on the cell surface as assessed by flow cytometry analysis. Pretreatment of monocytes with actinomycin D completely abrogated the effect of IL-10, suggesting a transcriptional regulation. Moreover, IL-10-treated monocytes showed a significantly enhanced functional responsiveness to FMLP with enhanced (three- to fourfold) chemotaxis and augmented (twofold) intracellular calcium mobilization. In polymorphonuclear neutrophils (PMN), IL-10 also mediated a twofold augmentation of FMLP-R expression. In parallel experiments, we observed that IL-10 could differentially modulate other chemotactic receptors. Hence, we observed that IL-10 augmented two-to threefold platelet-activating factor receptor (PAF-R) expression, whereas it had no significant effect on the fifth component of complement (C5a) receptor (C5a-R) expression. Collectively, our results demonstrate that IL-10 may play an important role in inflammatory process through modulation of chemotactic receptor expression.