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PROBLEM: We investigated if the PROGINS mutation increases the risk of hepatitis E virus (HEV) infection in liver transplant recipients. METHODS: PROGINS was analysed through KASP assay; HEV serologies assessed via ELISA and multiplex cytokine assays were evaluated in plasma with the ProcartaPlex human immunoassay. RESULTS: Seventy liver transplant recipients were evaluated, of which 23 (33%) were HEV IgG-positive (HEV+). The frequency of PROGINS in the HEV+ group was 34%, compared to 14% in those that were HEV IgG negative (HEV−). Cytokine measurements in a sub-set of samples from HEV+/PROGINS+ individuals showed decreased plasma levels of MIG (monokine induced by gamma interferon), APRIL (A proliferation-inducing ligand) and SCF (stem cell factor), as well as increased levels of eotaxin-3 and interleukin-31 compared to those HEV−/PROGINS− samples. CONCLUSIONS: Our findings suggest an association between the PROGINS mutation and seropositivity for HEV in liver transplant recipients with consequent distorted cytokine levels.

Objective Primary Sjögren syndrome (pSS) is characterized by T and B cell infiltration of exocrine glands. The cysteine protease cathepsin S (CatS) is crucially involved in MHCII processing and T cell stimulation, and elevated levels have been found in patients with RA, psoriasis and pSS. However, little is known about the functional characteristics and mechanisms of SS-A- and SS-B-specific T cells in pSS patients. We herein investigated the inhibition of CatS activity in different biocompartments of pSS patients including antigen-specific T cell responses. Methods Ex vivo CatS activity was assessed in tears, plasma and saliva of 15 pSS patients and 13 healthy controls (HC) and in the presence or absence of the specific CatS inhibitor RO5459072. In addition, antigen (SS-A (60kD), SS-B, influenza H3N2, tetanus toxoid and SEB)-specific T cell responses were examined using ex vivo IFN-γ/IL-17 Dual ELISPOT and Bromdesoxyuridin (BrdU) proliferation assays in the presence or absence of RO5459072. Supernatants were analysed for IL-1β, IL-6, IL-10, TNF-α, IL-21, IL-22 and IL-23, using conventional ELISA. Results CatS activity was significantly elevated in tear fluid, but not other biocompartments, was inversely associated with exocrinic function in pSS patients and could significantly be suppressed by RO5459072. Moreover, CatS inhibition by RO5459072 led to strong and dose-dependent suppression of SS-A/SS-B-specific T cell effector functions and cytokine secretion by CD14+ monocytes. However, RO5459072 was incapable of suppressing SS-A/SS-B-induced secretion of cytokines in CD14+ monocytes when T cells were absent, confirming a CatS/MHCII-mediated mechanism of suppression. Conclusion CatS activity in tear fluid seems to be a relevant biomarker for pSS disease activity. Conversely, CatS inhibition diminishes T cell and associated monokine responses towards relevant autoantigens in pSS. Thus, CatS inhibition may represent a promising novel treatment strategy in pSS. Electronic supplementary material The online version of this article (10.1186/s13075-019-1955-2) contains supplementary material, which is available to authorized users.

In a pilot study, we showed that the intermittent administration of benznidazole in chronic Chagas disease patients resulted in a low rate of treatment suspension and therapeutic failure, as assessed by quantitative PCR (qPCR) at the end of treatment. Here, a 3-year posttreatment follow-up study of the same cohort of patients is presented. The treatment scheme consisted of 12 doses of benznidazole at 5 mg/kg of body weight/day in two daily doses every 5 days. Parasite load, Trypanosoma cruzi-specific antibodies, and serum chemokine levels were measured prior to treatment and after a median follow-up of 36 months posttreatment by DNA minicircle kinetoplastid and nuclear DNA satellite sequence qPCR methods, conventional serological techniques, a Luminex-based assay with recombinant T. cruzi proteins, and a cytometric bead array. At the end of follow-up, 14 of 17 (82%) patients had negative qPCR findings, whereas three of 17 (18%) had detectable nonquantifiable findings by at least one of the qPCR techniques. A decline in parasite-specific antibodies at 12 months posttreatment was confirmed by conventional serological tests and the Luminex assays. Monocyte chemoattractant protein 1 levels increased after treatment, whereas monokine induced by gamma interferon levels decreased. New posttreatment electrocardiographic abnormalities were observed in only one patient who had cardiomyopathy prior to treatment. Together, these data strengthen our previous findings by showing that the intermittent administration of benznidazole results in a low rate of treatment suspension, with treatment efficacy comparable to that of a daily dose of 5 mg/kg for 60 days. Fil: Alvarez, María Gabriela. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; Argentina Fil: Ramirez Gomez, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina Fil: Bertocchi, Graciela Luciana. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; Argentina Fil: Fernandez, Marisa Liliana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina Fil: Hernandez Vasquez, Yolanda Maria. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina Fil: Lococo, Bruno Edgardo. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; Argentina Fil: Lopez Albizu, Maria Constanza. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina Fil: Schijman, Alejandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina Fil: Checura, Cintia Carolina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina Fil: Abril, Marcelo. Fundación Mundo Sano; Argentina Fil: Laucella, Susana Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina Fil: Tarleton, Rick L.. University of Georgia; Estados Unidos Fil: Natale, Maria Ailen. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Castro Eiro, Melisa Daiana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sosa-Estani, Sergio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina. Instituto de Efectividad Clínica y Sanitaria; Argentina Fil: Viotti, Rodolfo Jorge. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; Argentina

Background: During periodontal inflammation, bacteria induces chemokine expression and migration of various inflammatory cells. The aim of the study was to learn if periodontal treatment alters salivary concentrations of macrophage activation-related chemokines and if such alterations correlate with abundance of periodontitis-associated bacteria. Methods: Twenty-five patients with periodontitis completed the study (NCT02913248 at clinicaltrials.gov). Periodontal parameters and stimulated saliva samples were obtained at baseline and 2, 6 and 12 weeks after non-surgical periodontal treatment. Salivary concentrations of monocyte chemoattractant proteins (MCP-1-4), macrophage-derived chemokine (MDC), macrophage migration inhibitory factor (MIF), monokine induced by interferon-gamma (MIG), macrophage inflammatory protein (MIP-1α) and interferon-inducible protein (IP-10) were quantified using the Luminex® xMAP™ technique and abundance of bacteria was quantified using next-generation sequencing. Results: The treatment improved all periodontal parameters and caused an increase in the concentrations of MCP-2, MDC and MIP-1α at week 12 compared to baseline, week 2 and week 6, respectively. Salivary concentrations of MCP-1-2, MDC, MIG, MIP-1α and IP-10 correlated with the abundance of specific periodontitis-associated bacteria. Conclusions: Periodontal treatment impacts salivary concentrations of MCP-2, MDC and MIP-1α, which correlate with the abundance of specific periodontitis-associated bacteria. This indicates that these chemokines reflect periodontal status and possess potential in illustrating a response to treatment.

Chemokines are a group of low molecular weight peptides. Their major function is the recruitment of leukocytes to inflammation sites, but they also play a key role in tumor growth, angiogenesis, and metastasis. In the last few years, accumulated experimental evidence supports that monokine induced by interferon (IFN)‐gamma (CXCL9), a member of CXC chemokine family and known to attract CXCR3‐ (CXCR3‐A and CXCR3‐B) T lymphocytes, is involved in the pathogenesis of a variety of physiologic diseases during their initiation and their maintenance. This review for the first time presents the most comprehensive summary for the role of CXCL9 in different types of tumors, and demonstrates its contradictory role of CXCL9 in tumor progression. Altogether, this is a useful resource for researchers investigating therapeutic opportunities for cancer.

Osteoarthritis (OA) is one of the most common causes of chronic disability in adults due to pain and altered joint function. Although most patients report pain and functional limitation, symptoms, age of onset and disease progression are extremely variable. While inflammation could play a central role in the OA pathogenesis and progression, many underpinning mechanisms are still unclear. A number of proinflammatory mediators have been found in OA joints and could play a role, such as IL-1, IL-6, IL-7, IL-8, IL-15, IL-17, IL-18, TNF-alpha, macrophage chemotactic protein (MCP)-1, interferon-induced protein (IP)-10, monokine induced by interferon (MIG), oncostatin M (OSM), growth-related oncogene (GRO)-alpha, chemokine (C-C-motif) ligand 19 (CCL19), macrophage inflammatory protein (MIP)-1beta, and TGF-alpha. Biological approaches have recently got increasing interest due to their anti-inflammatory and immunomodulatory properties, regenerative potential, and high tolerability. The primary aim of this paper is to report the current concepts on regenerative medicine for knee OA with a particular focus on Autologous Protein solution (APS). APS is a blood derived product obtained by using a proprietary device, made of APS Separator, which isolates WBCs and platelets in a small volume of plasma, and APS Concentrator, which further concentrates platelets, WBCs and plasma proteins. The result is a peculiar formulation differing from other biologic products as it contains high levels of growth factors (EGF, IGF-1, PDGF-AB, PDGF-BB, VEGF, TGF-β1) along with high concentrations of anti-inflammatory mediators (IL-1ra, sIL-1RII, sTNF-RI, sTNF-RII) and low levels of pro-inflammatory cytokines (Il-1β and TNF-α). While emerging evidence supports the use of APS, as confirmed by in vitro studies and preliminary clinical results, the real clinical potential of APS and its benefits are still under investigation.

Staphylococcus aureus is the leading cause of skin and skin structure infection (SSSI), a primary portal of entry for invasive infection. Our prior studies discovered a role for protective innate memory against recurrent methicillin-resistant S. aureus (MRSA) SSSI. In the present study, the dynamics and mechanisms of this response were explored in recurrent SSSI in WT mice. Priming by prior infection reduced skin lesion severity and MRSA burden, and protected against dissemination at day 7 but not day 2. Cytokine and cellular signatures in SSSI differed at day 2 versus 7, and were distinct in skin versus blood or spleen. Cytokines associated with protection in skin included increased IL-17, IL-6, monokine inducible by IFN-γ (MIG), and RANTES, while increased IP-10 correlated with protection from dissemination. Cellular signatures of protection included increased Th17, M1 macrophage, and dendritic cell populations in abscesses, and total macrophages in lymph nodes. Priming potentiated S. aureus-specific phagocytic killing by bone marrow-derived macrophages in vitro, and their adoptive transfer into naive skin afforded protective efficacy in vivo. Present findings indicate that protective immunity in recurrent S. aureus infection is locally targeted, and involves specific memory conferred by macrophages. These insights provide targets for vaccine and immunotherapeutic development against MRSA.

Lymphoma-associated hemophagocytic syndrome (LAHS) is a serious disorder, and its early diagnosis and treatment with appropriate chemotherapy are very important. However, reliable markers for early diagnosis of LAHS have not been identified. We screened serum cytokines using a newly introduced assay system, cytometric bead array (CBA), and identified interferon-inducible protein 10 (IP-10)/CXCL10 and monokine induced by interferon gamma (MIG)/CXCL9 as useful markers. Serum concentrations of IP-10 and MIG at the time of LAHS diagnosis were greater than 500 and 5,000 pg/ml, respectively. The sensitivity and specificity for LAHS diagnosis were 100 and 95 %, respectively, when we set the above values as the cut-off levels. Serum levels of these two chemokines were already elevated at the time of admission and significantly decreased after successful treatment, indicating their usefulness for both the diagnosis and therapeutic outcomes for LAHS. IP-10 and MIG were also useful in distinguishing severe from moderate/mild LAHS, and B-cell-type LAHS from T-cell/natural killer cell-type LAHS. Furthermore, IP-10 and MIG were of use to distinguish LAHS from sepsis in patients with hematologic malignancies. Rapid measurement of IP-10 and MIG by CBA appeared to be important for early diagnosis and treatment of LAHS.

Thai patients with scrub typhus caused by the intracellular pathogen Orientia tsutsugamushi displayed elevated plasma concentrations of granzymes A and B, interferon-gamma (IFN)-gamma-inducible protein 10, and monokine induced by IFN-gamma. These data suggest that activation of cytotoxic lymphocytes is part of the early host response to scrub typhus.

金沢大学大学院医学系研究科血管分子科学, Background: Although chemokines play an important role in various inflammatory diseases, there have been few studies about the role of chemokines in alopecia areata (AA). Objectives: To determine serum levels of chemokines in patients with AA and their clinical correlations. Methods: Serum samples from 85 patients with AA, 20 patients with atopic dermatitis, 20 patients with psoriasis vulgaris and 28 normal controls were examined by the cytometric bead array assay assessing monokine induced by interferon (IFN)-γ (MIG), RANTES, interleukin-8 (IL-8), IFN-inducible protein-10, monocyte chemoattractant protein-1, macrophage inflammatory protein (MIP)-1α, MIP-1β and eotaxin levels. Secreted chemokine levels from peripheral blood mononuclear cells (PBMC) of patients with AA were also investigated. Results: Serum MIG, RANTES, IL-8 and eotaxin levels were selectively increased in patients with AA compared with normal controls. Levels of MIG, RANTES and IL-8 secreted from PBMC of patients with AA were also increased. Furthermore, elevated serum MIG and RANTES levels significantly correlated with the disease activity. RANTES levels were nonsignificantly associated with a predisposition to atopy. Conclusions: These results suggest that MIG and RANTES play an important role in the development of AA and are useful as markers of disease activity and as therapeutic targets. © 2007 The Authors.全文公開200809

Monokines (i.e., interleukin [IL]-12, -18, and -15) induce natural killer (NK) cells to produce interferon-gamma (IFN-gamma), which is a critical factor for immune surveillance of cancer and monocyte clearance of infection. We show that SET, which is a potent inhibitor of protein phosphatase type 2A (PP2A) activity, is highly expressed in human CD56bright NK cells, which produce more IFN-gamma than CD56dim NK cells. SET was up-regulated upon monokine stimulation of primary human NK cells. Furthermore, ectopic overexpression of SET significantly enhanced IFN-gamma gene expression in monokine-stimulated NK cells. In contrast, RNAi-mediated suppression of SET expression renders NK cells inefficient in producing high levels of IFN-gamma in response to monokine costimulation. Mechanistically, suppression of PP2A activity by SET is important for IFN-gamma gene expression in NK cells. In fact, treatment of primary human NK cells with the PP2A activator 1,9-dideoxy-forskolin, as well as administration of the drug to C57BL/6 mice, significantly reduced NK-dependent IFN-gamma production in response to monokine treatment. Further, SET knockdown or pharmacologic activation of PP2A diminished extracellular signal-regulated kinase 1/2, p65RelA, signal transducer and activator of transduction 4 (STAT4), and STAT5 activity in monokine-stimulated NK cells, potentially contributing to the reduction in IFN-gamma gene expression. Thus, SET expression is essential for suppressing PP2A phosphatase activity that would otherwise limit NK cell antitumoral and/or antiinflammatory functions by impairing NK cell production of IFN-gamma.

Background: Exaggerated activation of cytokines/chemokines has been proposed as a factor in adverse outcome of severe acute respiratory syndrome (SARS). Previous studies on chemokines have included only small numbers of patients, and the utility of plasma chemokines as prognostic indicators is unclear.Methods: We studied 255 archival plasma samples collected during the first or second week after disease onset. The chemokines interferon-inducible protein-10 (IP-10), monokine induced by interferon-γ (MIG), interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1), and regulated upon activation normal T cell expressed and secreted (RANTES) were measured by cytometric bead array with a 4-color FACSCalibur flow cytometer. Reverse transcription and real-time quantitative PCR and immunohistochemical staining were performed to analyze the production of IP-10 in lung tissue at autopsy. Conditional logistic regression was used to identify independent predictors for adverse disease outcome.Results: Increases in IP-10, MIG, and IL-8 during the first week after onset of fever were associated with adverse outcome (intensive care unit admission or death) in the univariate analysis. During the second week, only MIG concentration was associated with prognosis. After adjusting for other risk factors, plasma IP-10 concentration at the first week remained as an independent prognostic factor, with an odds ratio for adverse outcome of 1.52 (95% confidence interval, 1.05–2.55) per fold increase in plasma IP-10 concentration above the median. During the second week, chemokines provided little independent prognostic information. IP-10 was increased in lung tissue from patients who died of SARS.Conclusions: Increased plasma IP-10 during the first week of SARS symptoms is an independent predictor of outcome. Chemokine activation may be an early event in SARS, and an exaggerated host response may produce complications.

The role of chemokines during some viral infections is unpredictable because the inflammatory response regulated by these molecules can have two, contrasting effects—viral immunity and immunopathologic injury to host tissues. Using Theiler's virus infection of SJL mice as a model of this type of disease, we have investigated the roles of two chemokines—regulated on activation, normal T cell-expressed and secreted (RANTES) chemokine and monokine induced by IFN-γ (MIG)—by treating mice with antisera that block lymphocyte migration. Control, infected mice showed virus persistence, mild inflammation and a small degree of demyelination in the white matter of the spinal cord at 6 weeks post-infection. Treatment of mice with RANTES antiserum starting at 2 weeks post-infection increased both viral antigen expression and the severity of inflammatory demyelination at 6 weeks post-infection. MIG antiserum increased the spread of virus and the proportion of spinal cord white matter with demyelination. Overall, viral antigen levels correlated strongly with the extent of pathology. At the RNA level, high virus expression was associated with low IL-2 and high IL-10 levels, and RANTES antiserum decreased the IL-2/IL-10 ratio. Our results suggest that RANTES and MIG participate in an immune response that attempts to restrict viral expression while limiting immunopathology and that anti-chemokine treatment poses the risk of exacerbating both conditions in the long term.

The approximately 50 known chemokines are classified in distinct subfamilies: CXC, CC, CX3C, and C. Although the signaling of chemokines often is promiscuous, signaling events between members of these distinct chemokine classes are hardly observed. The only known exception so far is the murine CC chemokine ligand (CCL)21 (secondary lymphoid tissue chemokine, Exodus-2, 6Ckine), which binds and activates the murine CXC chemokine receptor CXCR3. However, this exception has not been found in humans. In this study, we provide evidence that human CCL21 is a functional ligand for endogenously expressed CXCR3 in human adult microglia. In absence of CCR7 expression, CCL21 induced chemotaxis of human microglia with efficiency similar to the CXCR3 ligands CXC chemokine ligand 9 (monokine induced by IFN-3γ) and CXC chemokine ligand 10 (IFN-γ-inducible protein-10). Because human CCL21 did not show any effects in CXCR3-transfected HEK293 cells, it is indicated that CXCR3 signaling depends on the cellular background in which the CXCR3 is expressed.

An allograft is often considered an immunologically inert playing field on which host leukocytes assemble and wreak havoc. However, we demonstrate that graft-specific physiologic responses to early injury initiate and promulgate destruction of vascularized grafts. Serial analysis of allografts showed that intragraft expression of the three chemokine ligands for the CXC chemo-kine receptor CXCR3 was induced in the order of interferon (IFN)-gamma-inducible protein of 10 kD (IP-10, or CXCL10), IFN-inducible T cell alpha-chemoattractant (I-TAC; CXCL11), and then monokine induced by IFN-gamma (Mig, CXCL9). Initial IP-10 production was localized to endothelial cells, and only IP-10 was induced by isografting. Anti-IP-10 monoclonal antibodies prolonged allograft survival, but surprisingly, IP-10-deficient (IP-10(-/-)) mice acutely rejected allografts. However, though allografts from IP-10(+/+) mice were rejected by day 7, hearts from IP-10(-/-) mice survived long term. Compared with IP-10(+/+) donors, use of IP-10(-/-) donors reduced intragraft expression of cytokines, chemokines and their receptors, and associated leukocyte infiltration and graft injury. Hence, tissue-specific generation of a single chemokine in response to initial ischemia/reperfusion can initiate progressive graft infiltration and amplification of multiple effector pathways, and targeting of this proximal chemokine can prevent acute rejection. These data emphasize the pivotal role of donor-derived IP-10 in initiating alloresponses, with implications for tissue engineering to decrease immunogenicity, and demonstrate that chemokine redundancy may not be operative in vivo.

Summary Human disease associated with influenza A subtype H5N1 reemerged in January, 2003, for the first time since an outbreak in Hong Kong in 1997. Patients with H5N1 disease had unusually high serum concentrations of chemokines (eg, interferon induced protein-10 [IP-10] and monokine induced by interferon γ [MIG]). Taken together with a previous report that H5N1 influenza viruses induce large amounts of proinflam-matory cytokines from macrophage cultures in vitro, our findings suggest that cytokine dysfunction contributes to the pathogenesis of H5N1 disease. Development of vaccines against influenza A (H5N1) virus should be made a priority.

Background: Complex biological processes such as acute inflammation induced by trauma/hemorrhagic shock/ (T/HS) are dynamic and multi-dimensional. We utilized multiplexing cytokine analysis coupled with data-driven modeling to gain a systems perspective into T/HS. Methodology/Principal Findings: Mice were subjected to surgical cannulation trauma (ST) 6 hemorrhagic shock (HS; 25 mmHg), and followed for 1, 2, 3, or 4 h in each case. Serum was assayed for 20 cytokines and NO2 2 /NO3 2 . These data were analyzed using four data-driven methods (Hierarchical Clustering Analysis [HCA], multivariate analysis [MA], Principal Component Analysis [PCA], and Dynamic Network Analysis [DyNA]). Using HCA, animals subjected to ST vs. ST + HS could be partially segregated based on inflammatory mediator profiles, despite a large overlap. Based on MA, interleukin [IL]-12p40/ p70 (IL-12.total), monokine induced by interferon-c (CXCL-9) [MIG], and IP-10 were the best discriminators between ST and ST/HS. PCA suggested that the inflammatory mediators found in the three main principal components in animals subjected to ST were IL-6, IL-10, and IL-13, while the three principal components in ST + HS included a large number of cytokines including IL-6, IL-10, keratinocyte-derived cytokine (CXCL-1) [KC], and tumor necrosis factor-a [TNF-a]. DyNA suggested that the circulating mediators produced in response to ST were characterized by a high degree of interconnection/complexity at all time points; the response to ST + HS consisted of different central nodes, and exhibited zero network density over the first 2 h with lesser connectivity vs. ST at all time points. DyNA also helped link the conclusions from MA and PCA, in that central nodes consisting of IP-10 and IL-12 were seen in ST, while MIG and IL-6 were central nodes in ST + HS. Conclusions/Significance: These studies help elucidate the dynamics of T/HS-induced inflammation, complementing other forms of dynamic mechanistic modeling. These methods should be applicable to the analysis of other complex biological processes.

The acute phase reaction is an early response aimed at the defence of the organism and at the re-establishment of homeostasis in response to acute infection, inflammation and other pathological states (Kushner, 1982). The putative mechanism responsible for this reaction is based on an initial signal derived from macrophages and other cells that synthesize and secrete several factors (probably cytokines) capable of inducing, in hepatocytes, a series of events. One of the most important mediators of the liver acute phase response is the monokine Interleukin (IL)-6 (Gauldie et al., 1987). The acute phase response consists in a change in the concentration of several plasma proteins, generally synthesized in the liver, including 1-glycoprotein (AGP), complement factor C3, serum amyloid A, Haptoglobin and Hemopexin.

Inflammatory cytokines have been implicated in the pathogenesis of rheumatoid arthritis (RA), whereas the mechanisms for constitutive production of inflammatory cytokines in affected joints are largely unknown. Recently, integrin-mediated interaction with extracellular matrix (ECM) proteins has been demonstrated to play a role in regulating cytokine production in T cells and monocytes. In this study, we investigated the contribution of the beta 1 integrin-mediated interaction with ECM proteins to the persistent cytokine gene expression in RA synovial fluid mononuclear cells (SFMNC). We examined mRNA expression of 14 cytokines in the SFMNC of three RA patients, which were either fresh or cultured overnight in serum-free medium on ECM-coated plates, by polymerase chain reaction with a panel of oligonucleotide primers specific for each cytokine. The persistent expression of various cytokine mRNA found in fresh SFMNC was maintained after overnight culture in serum-free medium on ECM proteins, especially on laminin (LM), but not on serum albumin. This effect of LM was inhibited by an anti-integrin beta 1 chain (CD29) mAb, as well as by an anti-CD3 mAb, indicating an important role of the beta 1 integrin-mediated interaction with ECM proteins in regulating persistent cytokine gene expression in RA SFMNC, and a key role of T cells in regulating inflammatory monokine production.

Identification of patients at risk of a complicated course after liver resection is crucial for adapting post-operative care. In the present study, we investigated the diagnostic value of the plasma levels of various cytokines obtained immediately after surgery. IL-6, IL-10, IL-8, monokine induced by interferon-γ (MIG), monocyte chemotactic protein-1 (MCP-1) and interferon-inducible protein-10 (IP-10) concentrations were measured in 26 patients after liver resection using a cytometric bead assay and were correlated with liver function, resectate weight, surgery duration, ischemia/reperfusion, hospitalization time and occurrence of complications. Patients with post-surgical complications showed distinctive patterns of IL-6 and IL-8 as early as minutes to hours after surgery. In addition, although pre-operative bilirubin in most patients remained within the normal range, a cut-off of 1 mg/dl separated the patients into groups with different profiles of IL-6, IL-8, and MCP-1 secretion and different likelihoods of experiencing post-operative complications (bilirubin levels ≥1.0 vs.

We investigated whether Notch signaling plays a role in regulating macrophage responses to inflammation. In a wound healing assay, macrophage recruitment was decreased in Notch1+/− mice, and the wounds were characterized by decreased TNF-α expression. As wound healing progressed, Notch1+/− wounds had increased vascularization and collagen deposition compared with wild-type wounds. In mice with myeloid-specific Notch1 deletion, wounds had decreased macrophage recruitment as well as decreased TNF-α expression, indicating the specific role of Notch1 in the inflammatory response in these cells. In vitro, we found that vascular endothelial growth factor receptor-1 (VEGFR-1) was upregulated in macrophages in response to LPS/IFN-γ and that this upregulation depended on Notch signaling. Furthermore, macrophages from Notch1+/− mice had decreased expression of VEGFR-1 compared with macrophages from wild-type mice, whereas VEGFR-1 expression in Notch4−/− macrophages was normal. Inhibition of Notch signaling decreased induction of the inflammatory cytokines IL-6, IL-12, CXCL10, MCP-1, monokine induced by IFN-γ, and TNF-α in macrophages in response to LPS/IFN-γ. Additionally, macrophages from Notch1+/− mice demonstrated decreased induction of IL-6, IL-12, and TNF-α in response to stimulation compared with wild-type mice. Thus, both pharmacological inhibition of Notch and genetic analysis demonstrate that Notch1 regulates VEGFR-1 and cytokine expression in macrophages. We have also established that Notch1 is important for the inflammatory response during wound healing in mice.

For many years the IFN-gamma ex vivo ELISPOT has been a major assay for assessing human T-cell responses generated by malaria vaccines. The ELISPOT assay is a sensitive assay, but an imperfect correlate of protection against malaria. Monokine induced by gamma (MIG), or CXCL9, is a chemokine induced by IFN-gamma and has the potential to provide amplification of the IFN-gamma signal. MIG secretion could provide a measure of bio-active IFN-gamma and a functional IFN-gamma signalling pathway. We report that detecting MIG by flow cytometry and by RT-PCR can be more sensitive than the detection of IFN-gamma using these methods. We also find that there is little inter-individual variability in MIG secretion when detected by flow cytometry and that the MIG assay may be used to estimate the amount of bio-active IFN-gamma present. Measurement of MIG alongside IFN-gamma may provide a fuller picture of Th1 type responses post-vaccination.

Diverse conditions for stimulating human mononuclear cells to release thymocyte costimulatory factors were tested for their contribution to the generation of supernatants containing high titers of these monokines. Activity titers increased with LPS concentration, reaching a plateau between 1 and 10 micrograms/ml. Indomethacin did not modify the monokine release, but the assay for thymocyte costimulatory activity was substantially affected by inhibitory substances produced by the monocytes in the absence of indomethacin. The use of nylon wool columns to trap the cells was shown to be effective in raising cellular densities without decreasing activity titers. As a result, the yield per cell could be maintained even in the absence of serum, an important step toward the goal of purifying bioactive peptides from crude broths.

Summary Interferon-inducible protein-10 (IP-10)/CXCL10, which is a ligand for CXC chemokine receptor 3 (CXCR3), is known to be involved in the pathogenesis of pulmonary sarcoidosis. However, the roles of monokine induced by interferon γ (Mig)/CXCL9 and interferon-inducible T cell α chemoattractant (I-TAC)/CXCL11, which are also CXCR3 ligands, remain unclear. Mig/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11 in both bronchoalveolar lavage fluid (BALF) and serum in patients with pulmonary sarcoidosis were measured by enzyme-linked immunosorbent assay (ELISA). The expression of these chemokines in alveolar macrophages was examined using ELISA, quantitative real-time polymerase chain reaction and immunostaining. In BALF, Mig/CXCL9 and IP-10/CXCL10 were significantly elevated in stage II sarcoidosis as compared with the levels in healthy volunteers. In serum, Mig/CXCL9 and I-TAC/CXCL11 were increased in stage II of the disease. The levels of all CXCR3 ligands in BALF were correlated with the numbers of both total and CD4+ lymphocytes. Alveolar macrophages were stained positive for all CXCR3 ligands and produced increased amounts of these chemokines. Positive staining of the three chemokines was also observed in the epithelioid and giant cells in the sarcoid lungs. These findings suggest that Mig/CXCL9 and I-TAC/CXCL11 as well as IP-10/CXCL10 play important roles in the accumulation of Th1 lymphocytes in sarcoid lungs.

The plasma concentrations of granzymes are considered to reflect the involvement of cytotoxic T-cells and natural killer cells in various disease states. Interferon (IFN)-γ-inducible protein-10 (IP-10) and monokine induced by IFN-γ (Mig) are members of the non-ELR CXC chemokine family that act on T-cells and natural killer cells. This study revealed that the plasma concentrations of granzyme B (but not granzyme A), IP-10 and Mig were higher in 44 Thai patients with definite or possible leptospirosis than in healthy blood donors. These data suggest that activation of cell-mediated immunity is part of the early host response to leptospirosis.

We describe for the first time a case of macrophage activation syndrome in a child with hyperimmunoglobulinemia D with periodic fever syndrome who required intensive care support. Up-regulated monokine production, high serum levels of triglycerides and ferritin, clotting abnormalities with hypofibrinogenemia, and rapidly evolving pancytopenia should alert the clinician to the possible diagnosis of macrophage activation syndrome, even in autoinflammatory diseases characterized basically by the periodic recurrence of unprovoked inflammatory attacks. Bone marrow aspiration showing well-differentiated macrophages phagocytosing hematopoietic elements remains the main tool for a final diagnosis, and cyclosporine is the best strategy for treatment.

Vaccinia virus is reactogenic in a significant number of vaccinees, with the most common adverse events being fever, lymphadenopathy, and rash. Although the inoculation is given in the skin, these adverse events suggest a robust systemic inflammatory response. To elucidate the cytokine response signature of systemic adverse events, we used a protein microarray technique to precisely quantitate 108 serum cytokines and chemokines in vaccine recipients before and 1 week after primary immunization with Aventis Pasteur smallpox vaccine. We studied 74 individuals after vaccination, of whom 22 experienced a systemic adverse event and 52 did not. The soluble factors most associated with adverse events were selected on the basis of voting among a committee of machine-learning methods and statistical procedures, and the selected cytokines were used to build a final decision-tree model. On the basis of changes in protein expression, we identified 6 cytokines that accurately discriminate between individuals on the basis of adverse event status: granulocyte colony-stimulating factor, stem cell factor, monokine induced by interferon-gamma (CXCL9), intercellular adhesion molecule-1, eotaxin, and tissue inhibitor of metalloproteinases-2. This cytokine signature is characteristic of particular inflammatory response pathways and suggests that the secretion of cytokines by fibroblasts plays a central role in systemic adverse events.

Psoriasis vulgaris, a skin disease that is considered to be the result of a type 1 autoimmune response, provides an opportunity for studying the changes that occur in a target-diseased tissue during innovative immunotherapies. To gain a more comprehensive picture of the response to an approved biological therapy, we studied alfacept, which is a CD2 binding fusion protein. We examined T cells, dendritic cells (DCs), and expression of a number of inflammatory genes. In 22 patients, 55% demonstrated a clear histological remission of the disease, with a 73% reduction in lesional lymphocytes and a 79% decrease in infiltrating CD8+cells. Only histological responders showed marked reductions in the tissue expression of inflammatory genes IFN-γ, signal transducer and activator of transcription 1, monokine induced by IFN-γ, inducible NO synthase, IL-8, and IL-23 subunits. Parallel decreases in CD83+and CD11c+DCs also were measured by immunohistochemistry. Because we observed that alefacept binds primarily to T cells and not DCs, we suggest that T cells are the primary target for therapy, but that DCs and a spectrum of type 1 inflammatory genes are coordinately suppressed.

CXCR3 chemokines are of particular interest because of their potential involvement in a variety of inflammatory diseases, including the rejection of organ transplants. Although the rat is one of the most appropriate animals for using to study transplantation biology, the structural and functional characteristics of CXCL9 [monokine induced by interferon-gamma (Mig)] in this experimental model have not been described. Therefore, we recently conducted a series of experiments to identify and characterize the rat CXCL9 gene. Accordingly, we isolated rat CXCL9 cDNA and genomic DNA. The rat CXCL9 gene encodes a protein of 125 amino acids and spans a 3.5 kbp DNA segment containing four exons in the protein-coding region. We then analysed mRNA expression in various tissues. Transcripts for the gene were found to be expressed at high levels in the lymph nodes and spleen. Then, to confirm the function of the identified gene, rat CXCL9 was transiently expressed in COS-1 cells. Rat recombinant Mig displayed chemotactic properties and induced CXCR3 internalization in CD4+ T cells. Lastly, we analysed the expression of rat CXCL9 in a heterotopic heart allograft model. Both mRNA and protein levels of intragraft CXCL9 were significantly increased following transplantation of ACI to LEW hearts when compared with syngeneic controls. These findings indicate that rat CXCL9 has an in vivo role in the infiltration of CD4+ T cells in the transplanted graft.

Transcript expression of 24 chemokines (CKs) was examined throughout 8 days in mouse lungs with type-1 (Th1) or type-2 (Th2) cytokine-mediated granulomas induced by bead-immobilized mycobacterial purified protein derivative or Schistosoma mansoni egg antigens. Where possible, CK protein levels were also measured. In addition, we examined effects of in vivo cytokine depletions. Findings were as follows: 1) bead challenge induced increases in 18 of 24 CK transcripts with type-1 and type-2 responses displaying different patterns. CKs fell into four categories: a) type-1-dominant (gamma-interferon-inducible protein (IP-10), monokine induced by INF-gamma (MIG), macrophage inflammatory protein-2 (MIP-2), lipopolysaccharide-induced chemokine (LIX), rodent growth-related oncogene homologue (KP), macrophage inflammatory protein-1alpha (MIP-1alpha) and -1beta (MIP-1beta), lymphotactin), b) type-2-dominant (eotaxin, monocyte chemotactic protein-2 (MCP-2) and -3 (MCP-3), liver and activation-regulated chemokine (LARC), T cell activation protein-3 (TCA-3), c) type-1 and type-2 co-dominant (MCP-1, MCP-5, monocyte-derived chemokine (MDC), thymus and activation-related chemokine (TARC), C10), and d) constitutive (lungkine, secondary lymphoid-tissue chemokine (SLC), EBI1-ligand chemokine (ELC), fractalkine, macrophage inflammatory protein-1gamma (MIP1-gamma), and stromal cell derived factor-1alpha (SDF1-alpha). 2) CKs displayed characteristic temporal patterns. CXC (IP-10, MIG, MIP-2, LIX, KC) and certain CC (MCP-1, MCP-5, MIP-1alpha, MIP-1beta) CKs were produced maximally within 1 to 2 days. Others (MCP-2, MCP-3, eotaxin, lymphotactin, LARC, TCA-3) displayed peak expression later. 3) Interferon-gamma neutralization profoundly abrogated MIG, but had little effect on other CKs. Tumor necrosis factor-alpha neutralization caused up to 50% reduction in a range of CKs. These findings indicate that type-1 and type-2 granulomas display characteristic CK profiles with coordinated expression that is under cytokine-mediated regulation.

BACKGROUND: Human peripheral blood mononuclear cells (PBMC) left in microcultures for 24h without mitogen do not respond to subsequent stimulation with PHA. They regain reactivity if the native culture medium is absorbed with other party lymphocytes or partially replaced with the medium from a PHA-stimulated culture. The observations suggest that, during the incubation, some inhibitory agent had accumulated in the culture medium. AIM: The study was performed to determine the nature of the observed phenomenon in respect of the possible role of monocytes and their products IL-1 and IL-1 receptor antagonist (IL-1ra), and to test for immunodiagnostic purposes the significance of quantifying the lymphocyte response to delayed stimulation with PHA in patients suffering from inflammatory prosesses. METHODS: Lymphocyte response to delayed stimulation with PHA, calculated as the lymphocyte-monokine interaction (LM) index, was determined in the microcultures of PBMC isolated from the blood of healthy donors or of patients with acute tonsilitis. The values of LM indices were compared with the ratios of IL-1ra/IL-1beta concentration estimated by enzyme-linked immunosorbent assay method in the culture supernatants. The influences of exogenous IL-1beta, IL-1ra, anti-IL1ra antibodies and antibiotic cefaclor on the monokine concentrations and on the values of LM index were tested. RESULTS AND CONCLUSIONS: The results show that the level of lymphocyte response to delayed stimulation with PHA (LM index) is inversely proportional to the ratio of IL-1ra/IL-1beta concentration in the culture. The low LM values at high IL-1ra/IL-1beta ratios in PBMC cultures from healthy donors, reversed proportions found in patients' PBMC (acute tonsilitis), and the cefaclor-induced reduction of LM value with correlated increase of the IL-1ra/IL-1beta ratio suggest that the LM assay may prove to be useful for immunodiagnostic purposes.

Macrophage inflammatory protein 1alpha (MIP-1alpha) promotes natural killer (NK) cell inflammation in livers during murine cytomegalovirus (MCMV) infections, and NK cell-produced interferon gamma (IFN-gamma) contributes to defense against MCMV infections. A specific role for local NK cell IFN-gamma production, however, has not been established. The importance of MIP-1alpha and NK cell-produced IFN-gamma in shaping endogenous immune responses and defense in different compartments was examined. MIP-1alpha deficiency profoundly decreased resistance to MCMV and was associated with dramatically reduced NK cell accumulation and IFN-gamma production in liver. MIP-1alpha-independent IFN-gamma responses were observed in serum and spleen, and infection-induced elevations in blood NK cell populations occurred in absence of the factor, but peak liver expression of another chemokine, the monokine induced by IFN-gamma (Mig), depended upon presence of MIP-1alpha, NK cells, and IFN-gamma. The Mig response was also important for viral resistance. Thus, serum cytokine responses are insufficient; MIP-1alpha is critical for NK cell migration and IFN-gamma delivery to mediate protection; and Mig induction in tissues is a downstream protective response resulting from the process. These results define a critical chemokine-to-cytokine-to-chemokine cascade required for defense during a viral infection establishing itself in tissues.

Gamma interferon (IFN-γ)-inducible protein 10 (IP-10) and monokine induced by IFN-γ (Mig) are related CXC chemokines which bind to the CXCR3 receptor and specifically target activated T lymphocytes and natural killer (NK) cells. The production of IP-10 and Mig by various cell types in vitro is strongly dependent on IFN-γ. To determine whether IP-10 and Mig are released during bacterial infection in humans, we measured plasma levels of IP-10 and Mig in patients with melioidosis, a severe gram-negative infection caused byBurkholderia pseudomallei. IP-10 and Mig were markedly elevated in patients with melioidosis on admission, particularly in blood culture-positive patients, and remained elevated during the 72-h study period. Levels of IP-10 and Mig showed a positive correlation with IFN-γ concentrations and also correlated with clinical outcome. In whole blood stimulated with heat-killedB. pseudomallei, neutralization of IFN-γ and tumor necrosis factor alpha (TNF-α) partly attenuated IP-10 and Mig release, while anti-interleukin-12 (IL-12) and anti-IL-18 had a synergistic effect. Stimulation with other bacteria or endotoxin also induced strong secretion of IP-10 and Mig. These data suggest that IP-10 and Mig are part of the innate immune response to bacterial infection. IP-10 and Mig may contribute to host defense in Th1-mediated host defense during infections by attracting CXCR3+Th1 cells to the site of inflammation.

Activated T lymphocytes accumulate early in atheroma formation and persist at sites of lesion growth and rupture, suggesting that they may play an important role in the pathogenesis of atherosclerosis. Moreover, atherosclerotic lesions contain the Th1-type cytokine IFN-gamma, a potentiator of atherosclerosis. The present study demonstrates the differential expression of the 3 IFN-gamma-inducible CXC chemokines--IFN-inducible protein 10 (IP-10), monokine induced by IFN-gamma (Mig), and IFN-inducible T-cell alpha chemoattractant (I-TAC)--by atheroma-associated cells, as well as the expression of their receptor, CXCR3, by all T lymphocytes within human atherosclerotic lesions in situ. Atheroma-associated endothelial cells (ECs), smooth muscle cells (SMCs), and macrophages (MO) all expressed IP-10, whereas Mig and I-TAC were mainly expressed in ECs and MO, as detected by double immunofluorescence staining. ECs of microvessels within lesions also expressed abundant I-TAC. In vitro experiments supported these results and showed that IL-1beta, TNF-alpha, and CD40 ligand potentiated IP-10 expression from IFN-gamma-stimulated ECs. In addition, nitric oxide (NO) treatment decreased IFN-gamma induction of IP-10. Our findings suggest that the differential expression of IP-10, Mig, and I-TAC by atheroma-associated cells plays a role in the recruitment and retention of activated T lymphocytes observed within vascular wall lesions during atherogenesis.

Chemokines direct tissue invasion by specific leukocyte populations. Thus, chemokines may play a role in multiple sclerosis (MS), an idiopathic disorder in which the central nervous system (CNS) inflammatory reaction is largely restricted to mononuclear phagocytes and T cells. We asked whether specific chemokines were expressed in the CNS during acute demyelinating events by analyzing cerebrospinal fluid (CSF), whose composition reflects the CNS extracellular space. During MS attacks, we found elevated CSF levels of three chemokines that act toward T cells and mononuclear phagocytes: interferon-gamma-inducible protein of 10 kDa (IP-10); monokine induced by interferon-gamma (Mig); and regulated on activation, normal T-cell expressed and secreted (RANTES). We then investigated whether specific chemokine receptors were expressed by infiltrating cells in demyelinating MS brain lesions and in CSF. CXCR3, an IP-10/Mig receptor, was expressed on lymphocytic cells in virtually every perivascular inflammatory infiltrate in active MS lesions. CCR5, a RANTES receptor, was detected on lymphocytic cells, macrophages, and microglia in actively demyelinating MS brain lesions. Compared with circulating T cells, CSF T cells were significantly enriched for cells expressing CXCR3 or CCR5. Our results imply pathogenic roles for specific chemokine-chemokine receptor interactions in MS and suggest new molecular targets for therapeutic intervention.

Gamma interferon (IFN-gamma) is a cytokine which plays a critical role in resistance to Mycobacterium tuberculosis infection. While T lymphocytes and natural killer cells are a major source of IFN-gamma, previous demonstrations that it can be produced by murine macrophages prompted us to examine the capacity of human alveolar macrophages to express IFN-gamma. Here we report that in vitro infection of alveolar macrophages with M. tuberculosis induces both the release of IFN-gamma protein and a transient increase in IFN-gamma mRNA levels. The IFN-producing cells were shown to be macrophages by reverse transcription-in situ PCR. We also observed that M. tuberculosis stimulation resulted in IFN-gamma-dependent expression of the chemokines IFN-gamma-inducible protein 10 and monokine induced by IFN-gamma, suggesting that macrophage-derived IFN-gamma can function in an autocrine and/or paracrine manner. The existence of a positive regulatory loop was suggested by the observation that exogenous IFN-gamma protein could induce IFN-gamma mRNA expression in uninfected alveolar macrophages. Interleukin-12 was also found to be a potent inducer of IFN-gamma production, and M. tuberculosis-induced IFN-gamma production appears to be mediated, at least in part, by IL-12. In contrast, M. tuberculosis-induced IFN-gamma production by alveolar macrophages could be blocked by exogenous interleukin-10. These studies are the first to demonstrate an autoregulatory role for IFN-gamma produced by alveolar macrophages infected in vitro with M. tuberculosis.

Recently, interferon-gamma-inducing-factor (IGIF) has been described as a novel monokine that is a more potent interferon-gamma (IFN-gamma) inducer than IL-12. By cloning IGIF from affected tissue and studying IGIF gene expression, we describe for the first time a close association of this cytokine with an autoimmune disease. The non-obese diabetic (NOD) mouse spontaneously develops autoimmune insulitis and diabetes which can be accelerated and synchronized by a single injection of cyclophosphamide. IGIF mRNA was demonstrated by reverse transcriptase PCR in NOD mouse pancreas during early stages of insulitis. Levels of IGIF mRNA increased rapidly after cyclophosphamide treatment and preceded a rise in IFN-gamma mRNA, and subsequently diabetes. Interestingly, these kinetics mimick that of IL-12p40 mRNA, resulting in a close correlation of individual mRNA levels. Cloning of the IGIF cDNA from pancreas RNA followed by sequencing revealed identity with the IGIF sequence cloned from Kupffer cells and in vivo preactivated macrophages. When extending our study to macrophages of the spleen we observed that NOD mouse macrophages responded to cyclophosphamide with IGIF gene expression while macrophages from Balb/c mice treated in parallel did not. The IGIF gene position is located within the Idd2 interval on mouse chromosome 9 and therefore it is a candidate for the Idd2 susceptible gene. We conclude that IGIF expression is abnormally regulated in autoimmune NOD mice and closely associated with diabetes development.

SUMMARY The effect of fibronectin on IL-1α, IL-1β, tumour necrosis factor-alpha (TNF-α), and IL-6 production was investigated with cultured monocytes isolated from human peripheral blood. Monokine concentrations were determined by both ELISA and bioassay. Fibronectin markedly stimulated the secretion of IL-1α, IL-1β, TNF-α and IL-6 from cultured monocytes in a dose-dependent manner, with the maximal effect apparent within 24 h. Northern blot analysis revealed a marked increase in the abundance of mRNA specific for each monokine on exposure of monocytes to fibronectin. Monoclonal antibodies to the α chain of very late antigen (VLA)-5, the β1 integrin, the α chain of Mac-1, and the β2 integrin, as well as the synthetic peptide of GRGDSP (which corresponds to the cell-binding domain of fibronectin), inhibited (>50%) fibronectin-induced monokine production. Monoclonal antibodies to the α chain of VLA-4, and the α chain of LFA-1, as well as the synthetic peptide CS-1 (which corresponds to the alternatively spliced connecting segment of fibronectin) and the control peptide GRADSP, had no inhibitory effect on monokine production. A MoAb, R60, that recognizes an epitope of the fibronectin molecule that includes the RGD sequence, inhibited monokine production, whereas the MoAb Y16, which recognizes another epitope of fibronectin not including RGD, did not. These results indicate that fibronectin-induced production of IL-1α, IL-1β, TNF-α and IL-6 from cultured monocytes is mediated predominantly by interaction of the cell-binding domain of fibronectin with VLA-5, although Mac-1 also may contribute to this effect of fibronectin. Our results indicate that the interaction of fibronectin with integrins may contribute to the cytokine network in inflammatory response.

SUMMARY Adhesion of inflammatory cells to endothelium is a critical step for their transvascular migration to inflammatory sites. To evaluate the relationship between T lymphocytes (TL) and vascular endothelium, supernatants from allergen-stimulated TL obtained from patients sensitive to Dermatophagoides pteronyssinus (Dpt) versus healthy subjects were added to endothelial cell (EC) cultures. TL were stimulated by autologous-activated antigen-presenting cells (APC) previously fixed in paraformaldehyde to prevent monokine secretion. Two parameters were measured: the expression of adhesion molecule and the production of IL-6. Related allergen-stimulated TL supernatants from allergic patients induced an increase of VCAM-1 and inter-cellular adhesion molecule-1 (ICAM-1) expression when supernatants of the control groups (TL exposed to an unrelated allergen or not stimulated or TL obtained from healthy subjects) did not, E-selectin expression was not modulated whatever the supernatant added to EC culture. IL-6 production by EC was significantly enhanced after activation with related allergen-stimulated TL supernatants from allergies compared with control supernatants. Induction of VCAM-1 expression was inhibited by adding neutralizing antibodies against IL-4, whereas IL-6 production and ICAM-I expression were inhibited by anti-interferon-gamma (IFN-γ) antibodies. Enhanced production of IL-4 and IFN-γ was detected in related allergen-stimulated TL supernatants from allergic subjects compared with the different supernatants. These data suggest that allergen-specific TL present in the peripheral blood of allergic patients are of Th1 and Th2 subtypes. Their stimulation in allergic patients may lead to the activation of endothelial cells and thereby participate in leucocyte recruitment towards the inflammatory site.

We have investigated the interaction of soluble peptidoglycan (sPG), in comparison with lipopolysaccharide (LPS), with human mononuclear cells (MNC) by determining the capacity of sPG to induce interleukin-6 (IL-6) and IL-1 release. In addition, we investigated the modulation of their interaction by anti-CD14 monoclonal antibody and by partial structures of LPS. We found that sPG, like LPS, was able to induce IL-6 and IL-1 production by MNC. However, dose-response experiments revealed that at least 3,000 ng of sPG per ml was necessary for induction, whereas the optimal LPS concentration was 1 ng/ml. Anti-CD14 monoclonal antibody reduced sPG- and LPS-induced IL-6 and IL-1 production. Moreover, partial structures of LPS were able to reduce monokine production induced by sPG and LPS. We conclude that sPG constitutes, like LPS, an inflammatory cytokine inducer and that CD14 is involved in the activation of human monocytes not only by LPS but also by sPG.