Interleukin 17A is an immune marker for chlamydial disease severity and pathogenesis in the koala (Phascolarctos cinereus)

The koala (Phascolarctos cinereus) is an iconic Australian marsupial species that is facing many threats to its survival. Chlamydia pecorum infections are a significant contributor to this ongoing decline. A major limiting factor in our ability to manage and control chlamydial disease in koalas is a limited understanding of the koala’s cell-mediated immune response to infections by this bacterial pathogen. To identify immunological markers associated with chlamydial infection and disease in koalas, we used koala-specific Quantitative Real Time PCR (qrtPCR) assays to profile the cytokine responses of Peripheral Blood Mononuclear Cells (PBMCs) collected from 41 koalas with different stages of chlamydial disease. Target cytokines included the principal Th1 (Interferon gamma; IFNγ), Th2 (Interleukin 10; IL10), and pro-inflammatory cytokines (Tumor Necrosis Factor alpha; TNFα). A novel koala-specific IL17A qrtPCR assay was also developed as part of this study to quantitate the gene expression of this Th17 cytokine in koalas. A statistically significant higher IL17A gene expression was observed in animals with current chlamydial disease compared to animals with asymptomatic chlamydial infection. A modest up-regulation of pro-inflammatory cytokines, such as TNFα and IFNγ, was also observed in these animals with signs of current chlamydial disease. IL10 gene expression was not evident in the majority of animals from both groups. Future longitudinal studies are now required to confirm the role played by cytokines in pathology and/or protection against C. pecorum infection in the koala.     

Pathophysiologic and prognostic role of proinflammatory and regulatory cytokines as a proinflammatory and regulatory cytokine in dengue fever

PurposeCytokines are important immune-modulators and improper T-cell activation can lead to cytokine storms which are believed to result in endothelial permeability and leakage, a typical feature of Dengue disease progressing into a more severe stage. Many cytokines have been implied in causing severe Dengue manifestations among which IL-10 poses to be an important one. Inflammatory cytokines such as TNFα and IFN γ can be pointed out in Dengue pathogenesis and prognosis. Therefore, we sought to investigate the T cell activation of Dengue infected patients via these three markers and asses their levels and correlate cytokine levels with disease severity and clinical outcomes.MethodsSamples using standard blood collection techniques were obtained from patients with clinical signs suggestive of dengue. A haematological was obtained subsequently. Serological markers including IgM and NS1 were assessed using ELISA following which ELISA will be done for immunological markers including TNFα, IFN γ (markers of pro-inflammatory response and IL-10 (marker for regulatory response).ResultsThere was a significant correlation between IL10 and clinical features. There was no significant correlation between TNF alpha and clinical features. IFN gamma had a positive correlation with the clinical features. There was a positive cumulative correlation between clinical features, platelet counts, IL10 and TNF alpha but not with IFN gamma contrary to its correlation as a separate entity with just the clinical features.ConclusionsThe present study clearly indicates that IL10 is a highly sensitive marker of Severe Dengue and can be used as a screening tool in Secondary Dengue patients or those with warning signs. TNF alpha as it correlates strongly with patients with warning signs can be used for prognosis is patients presenting with symptoms. However, interferon gamma correlates strongly with low platelet counts and can be a measure to screen patients presenting with fever with thrombocytopenia.     

Comparative analysis of spontaneous and mycobacterial antigen-induced secretion of Th1, Th2 and pro-inflammatory cytokines by peripheral blood mononuclear cells of tuberculosis patients

The cytokines produced by T helper (Th)1 cells (IFN‐γ, IL‐2 and TNF‐β) correlate with protection, whereas the cytokines released by Th2 cells (IL‐4, IL‐5) and the anti‐inflammatory cytokine IL‐10 correlate with pathogenesis of tuberculosis (TB). However, the pro‐inflammatory cytokines (IL‐1β, IL‐6, IL‐8, TNF‐α and IL‐12p70) are responsible for both protection and pathogenesis of TB. The aim of this work was to carry out a comparative analysis of cytokines present in early (day 2) and late (day 6) cultures of peripheral blood mononuclear cells (PBMCs) obtained from pulmonary tuberculosis patients. PBMCs were cultured in vitro in the absence and presence of exogenously added complex mycobacterial antigens and RD1 peptide pool. The supernatants were collected on day 2 and day 6 of culture and assayed for secreted cytokines using the flow cytomix assay. All of the cytokines, except for IL‐12p70, were spontaneously secreted by PBMCs of 27–100% TB patients, but only TNF‐α concentration was significantly higher on day 2 than day 6 (P < 0.05). Two days following antigenic stimulation, only IL‐1β, IL‐6, TNF‐α and IL‐10 were secreted in response to some mycobacterial antigens. However, 6 days later, all of the cytokines, except for IL‐2, IL‐4, IL‐5 and IL‐8, were secreted significantly in response to all complex antigens and RD1 peptides, compared with the non‐stimulated cultures (P < 0.05). In conclusion, the study shows that the longer in vitro stimulation time (6 days) was necessary for the optimal induction of IFN‐γ and TNF‐β, and practically convenient for the detection of IL‐10, IL‐1 β, TNF‐α and IL‐6.     

Impaired cytokine responses in patients with cryopyrin‐associated periodic syndrome (CAPS)

Cryopyrin‐associated periodic syndrome (CAPS) is characterized by dysregulated inflammation with excessive interleukin (IL)‐1β activation and secretion. Neonatal‐onset multi‐system inflammatory disease (NOMID) is the most severe form. We explored cytokine responses in 32 CAPS patients before and after IL‐1β blocking therapy. We measured cytokines produced by activated peripheral blood monuclear cells (PBMCs) from treated and untreated CAPS patients after stimulation for 48 h with phytohaemagglutinin (PHA), PHA plus IL‐12, lipopolysaccharide (LPS) or LPS plus interferon (IFN)‐γ. We measured IL‐1β, IL‐6, IL‐10, tumour necrosis factor (TNF), IL‐12p70 and IFN‐γ in the supernatants. PBMCs from three untreated CAPS patients were cultured in the presence of the IL‐1β blocker Anakinra. Fifty healthy individuals served as controls. CAPS patients had high spontaneous production of IL‐1β, IL‐6, TNF and IFN‐γ by unstimulated cells. However, stimulation indexes (SIs, ratio of stimulated to unstimulated production) of these cytokines to PHA and LPS were low in NOMID patients compared to controls. Unstimulated IL‐10 and IL‐12p70 production was normal, but up‐regulation after PHA and LPS was also low. LPS plus IFN‐γ inadequately up‐regulated the production of IL‐1β, IL‐6, TNF and IL‐10 in CAPS patients. In‐vitro but not in‐vivo treatment with Anakinra improved SIs by lowering spontaneous cytokine production. However, in‐vitro treatment did not improve the low stimulated cytokine levels. Activating mutations in NLRP3 in CAPS are correlated with poor SIs to PHA, LPS and IFN‐γ. The impairment in stimulated cytokine responses in spite of IL‐1β blocking therapy suggests a broader intrinsic defect in CAPS patients, which is not corrected by targeting IL‐1β.     

GRACE score of myocardial infarction patients correlates with oxidative stress index,hsCRP and inflammation

BackgroundEtiopathogenesis of myocardial infarction (MI) is contributed by oxidative injury and inflammatory response. The interplay of these processes determines outcomes in MI patients. However, studies showing the relationship of oxidative stress and inflammatory cytokines with prognosis and severity of MI are lacking.ObjectiveThe present study was designed to assess the degree of oxidative stress and inflammation in correlation with GRACE (Global Registry of Acute Coronary Events) risk score in patients of MI.MethodsMI patients were segregated according to GRACE risk score and age. Blood samples of the patients were used for determination of level of total peroxide, Total Antioxidant Status (TAS), Oxidative Stress Index (OSI), pro-inflammatory molecules such as high sensitive C-reactive protein (hsCRP), Tumor Necrosis Factor α (TNFα), interleukin 1 β (IL 1β), interleukin 6 (IL 6), anti-inflammatory cytokine interleukin 10 (IL 10), and TNFα/IL 10 cytokine ratio.ResultsWe found significant elevation in concentration of total peroxide, TAS and OSI in all MI patients than healthy volunteers, this elevation showed pronouncement with higher GRACE score (GS) and age. Alteration in pro-inflammatory and anti-inflammatory cytokines was seen in MI patients than control group, and this alteration displayed polarization with GS and age.ConclusionMI patients with higher GS and age have greater degree of OSI and inflammation, and these biochemical parameters were significantly correlated with GS and thus disease severity.     

Pharmacokinetics and pharmacodynamics of pegylated interferon lambda-1 in cynomolgus monkeys

Type III lambda interferons (IFNs) have activity similar to type I IFNs, but a more restricted receptor distribution. A pegylated human IFN lambda-1 (pegIFNλ) is under development for chronic hepatitis C. Induction of receptor signaling (STAT1 phosphorylation) and expression of interferon-stimulated genes (ISGs) by pegIFNλ were assessed in, respectively, cynomolgus monkey leukocyte subsets and hepatocytes stimulated in vitro. ISG induction by pegIFNλ or IFNα was also assessed in peripheral leukocytes and liver biopsies after single and repeat (x3) dosing of pegIFNλ (0.03, 0.3, 3.0 mg/kg) or unpegylated IFNα-2b (10(7) IU/kg). Single-dose pharmacokinetics of pegIFNλ were evaluated. Strong ISG induction occurred in cultured hepatocytes and liver biopsies with both pegIFNλ and IFNα. However, STAT1 phosphorylation, MHC class 1 upregulation, and ISG induction in leukocytes only occurred with IFNα. Serum neopterin was unaffected by pegIFNλ; however, β-2-microglobulin was elevated at all doses. The terminal half-life of pegIFNλ was 23 h with a 59 mL/kg volume of distribution, consistent with other pegylated IFNs. Serum exposure was dose-proportional across the dosing range. These data demonstrate the suitability of cynomolgus monkeys for the preclinical evaluation of pegIFNλ. Additionally, the absence of pegIFNλ pharmacologic activity in leukocytes is consistent with its low receptor expression in blood.     

T-cells producing multiple combinations of IFNγ, TNF and IL10 are associated with mild forms of dengue infection

Multifunctional interleukin 10 (IL10)⁺Th1 cells have been implicated in favorable evolution of many infectious diseases, promoting an efficacious immune response while limiting immunopathology. Here, we investigated the presence of multifunctional CD4⁺ and CD8⁺ T-cells that expressed interferon gamma (IFNγ), IL10 and tumor necrosis factor (TNF), or its combinations during dengue infection. Peripheral blood mononuclear cells (PBMCs) from outpatients with dengue (mild dengue forms) and hospitalized patients (or patients with dengue with warning signs and severe dengue) were cultured in the presence of envelope (ENV) or NS3 peptide libraries of DENV during critical (hospitalization period) and convalescence phases. The production of IFNγ, IL10 and TNF by CD4⁺ and CD8⁺ T-cells was assessed by flow cytometry. Our data show that patients with mild dengue, when compared with patients with dengue with warning signs and severe dengue, presented higher frequencies of multifunctional T-cells like NS3-specific IFNγ/IL10-producing CD4⁺ T-cells in critical phase and NS3- and ENV-specific CD8⁺ T-cells producing IFNγ/IL10. In addition, NS3-specific CD8⁺ T-cells producing high levels of IFNγ/TNF and IFNγ/TNF/IL10 were also observed in the mild dengue group. We observed that multifunctional T-cells produced higher levels of cytokines as measured by intracellular content when compared with single producer T-cells. Importantly, multifunctional CD4⁺ and CD8⁺ T-cells producing IFNγ, TNF and IL10 simultaneously displayed positive correlation with platelet levels, suggesting a protective role of this population. The presence of IL10⁺Th1 and IL10⁺Tc1 multifunctional cells was associated with mild dengue presentation, suggesting that these cells play a role in clinical evolution of dengue infection.     

Hepatitis C virus load and expression of a unique subset of cellular genes in circulating lymphoid cells differentiate non‐responders from responders to pegylated interferon alpha–ribavirin treatment

Based on investigations of liver biopsy material, certain cellular genes have been implicated as correlates of success or failure to interferon alpha–ribavirin (IFN/RBV) therapy against hepatitis C. The current study aimed at determining whether expression of host genes thought to be relevant to HCV replication in the liver would be correlated with HCV infection status in peripheral blood mononuclear cells (PBMCs) and also with patient responsiveness to IFN/RBV treatment. Therefore, PBMCs from patients with chronic hepatitis C responding (n = 35) or not (n = 49) to IFN/RBV and from healthy controls (n = 15) were evaluated for HCV RNA load and cellular gene expression. Non‐responders had 3‐ to 10‐fold higher basal levels of interleukin (IL)‐8, IFN‐stimulated gene 15 (ISG15), 2′,5′‐oligoadenylate synthetase (OAS), and Toll‐like receptors (TLR)‐4, ‐5, and ‐7 compared to responders. Non‐responders with similar post‐treatment follow‐ups as responders persistently expressed 6‐ to 20‐fold greater levels of IL‐8, ISG15, and OAS after therapy. Higher expression of IFN‐α, IFN‐γ, and IFN‐λ was found in PBMCs of individuals achieving sustained virological response, either before or after therapy. Pre‐treatment HCV RNA loads in PBMCs of non‐responders were significantly higher (P = 0.016) than those of responders. In conclusion, the data indicate that immune cells of responders and non‐responders to IFN/RBV therapy exhibited significantly different virological and host gene expression profiles. Elevated baseline HCV loads and TLR‐4, ‐5, and ‐7 levels, and persistently high levels of IL‐8, ISG15, and OAS were correlated with IFN non‐responsiveness. The results warrant further investigations on the utilization of PBMCs for predicting success or failure to IFN‐based therapies. J. Med. Virol. 85:441–448, 2013. © 2012 Wiley Periodicals, Inc.     

Reduced in vitro production of interferon-gamma, interleukin-4 and interleukin-12 and increased production of interleukin-6, interleukin-10 and tumour necrosis factor-alpha in systemic lupus erythematosus. Weak correlations of cytokine production with disease activity

Production of cytokines in unstimulated and mitogen-stimulated cultures were evaluated by ELISPOT in 34 SLE patients with low to moderate disease activity and 23 healthy controls. Significantly reduced production of IFN gamma, IL4 and IL12 and significantly increased production of IL6, IL10 and TNF alpha were found in patients with SLE. Regression analysis revealed that production of all six cytokines tended to decrease with increasing disease activity, but negative correlation with SLEDAI was significant (p < 0.05) only for PHA-stimulated IL4, unstimulated and PHA-stimulated IL10 and SAC-stimulated IL6. Negative correlation of stimulated and unstimulated IL6 and TNF alpha production with anti-DNA antibody levels were also significant.     

Tributyltin exposure alters cytokine levels in mouse serum

Tributyltin (TBT), a toxic environmental contaminant, has been widely utilized for various industrial, agricultural and household purposes. Its usage has led to a global contamination and its bioaccumulation in aquatic organisms and terrestrial mammals. Previous studies suggest that TBT has debilitating effects on the overall immune function of animals, rendering them more vulnerable to diseases. TBT (at concentrations that have been detected in human blood) alters secretion of inflammatory cytokines from human lymphocytes ex vivo. Thus, it is important to determine if specified levels of TBT can alter levels of cytokines in an in vivo system. Mice were exposed to biologically relevant concentrations of TBT (200, 100 or 25?nM final concentrations). The quantitative determination of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL2, IL5, IL7, IL12βp40, IL13, IL15, keratinocyte chemoattractant (KC), macrophage inflammatory protein 1β (MIP), MIP2 and regulated on activation normal T-cell-expressed and secreted (RANTES) was performed in mouse sera by MAGPIX analysis and Western blot. Results indicated alterations (both decreases and increases) in several cytokines. The pro-inflammatory cytokines IFNγ, TNFα, IL-1β, IL-2, IL5, IL12βp40 and IL-15 were altered as were the chemokines MIP-1 and RANTES and the anti-inflammatory cytokine IL-13. Increases in IFNγ and TNFα were seen in the serum of mice exposed to TBT for less than 24?h. Levels of IL1β, IL-12 βp40, IL-5 and IL-15 were also modulated in mouse serum, depending on the specific experiment and exposure level. IL-2 was consistently decreased in mouse serum when animals were exposed to TBT. There were also TBT-induced increases in MIP-1β, RANTES and IL-13. These results from human and murine samples clearly suggest that TBT exposures modulate the secretion inflammatory cytokines.     

Trypanosoma carassii hsp70 increases expression of inflammatory cytokines and chemokines in macrophages of the goldfish (Carassius auratus L.)

We report on the cloning and characterization of Trypanosoma carassii 70 KDa heat shock protein (hsp70). T. carassii hsp70 was secreted/excreted into culture medium in vitro and was recognized by sera from infected fish. Recombinant hsp70 (rhsp70) activated goldfish macrophages and stimulated the production of pro-inflammatory cytokines including interferon gamma (IFNγ), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, (IL)-12 and chemokines CCL-1 and CXCL-8 (IL-8). T. carassii hsp70-induced cytokine expression was abrogated by pronase treatment of macrophages confirming the existence of receptor(s) on goldfish macrophage surface that recognize parasite molecule. Parasite hsp70 also up-regulated the expression inducible nitric oxide synthase (iNOS) isoforms A and B and induced a strong nitric oxide response of goldfish macrophages.     

Profil des cytokines associées à la protection contre les accès palustres au cours de la grossesse en zone hypo-endémique au Sénégal

Background: Malarial infection in non immune pregnant women is a major risk factor for pregnancy failure. However in malaria endemic areas, intermittent preventive treatment (IPTp) have been adopted to prevent malaria in pregnancy women since 2003 in Senegal. The impact of IPT on the development of immunity is not very well documented. We conducted a prospective study at the RoiBaudouin maternity hospital of Guediawaye in Senegal to assess IL10, IL12, TNFα and IFNγ cytokines production in pregnant women under IPTp. Cytokines were analyzed in 82 sera at inclusion and delivery. P. falciparum HRP2 antigen was detected in 17% of women included by rapid diagnostic test (RDT). At inclusion the mean of IL10 response was higher in P. falciparum negative women (8 UA) compare to RDT-positive women (7 UA) p=0.069 while in delivery the opposite was found p=0.014. Low production of inflammatory cytokines IL12, IFNγ and TNFα was noted in both groups. Between inclusion and delivery, a significant increase of IL-10 production was noted while a decrease of IFNγ and TNFα cytokine was noted. Thus, IL12 and IFNγ responses may synergistically associate as malaria immune response during pregnancy.     

Inborn errors of interferon (IFN)-mediated immunity in humans: insights into the respective roles of IFN-α/β, IFN-γ, and IFN-λ in host defense

Summary: Interferon (IFN) was originally identified as a substance ‘interfering’ with viral replication in vitro. The first IFNs to be identified were classified as type I IFNs (IFN-α/β and related molecules), two other types have since been identified: type II IFN (IFN-γ) and type III IFNs (IFN-λ). Each IFN binds to one of three type-specific receptors. In the mouse model of experimental infections in vivo, IFN-α/β are essential for immunity to most viruses tested, whereas IFN-γ is important for immunity to a smaller number of viruses, together with bacteria, fungi, and parasites, consistent with IFN-γ acting as the ‘macrophage activating factor.’ The precise role of IFN-λ remains unclear. In recent years, inborn errors affecting the production of, or the response to, IFNs have been reported in human patients, shedding light onto the function of IFNs in natura. Disorders of IFN-γ production, caused by IL12B, IL12RB1, and specific NEMO mutations, or of IFN-γ responses, caused by IFNGR1, IFNGR2, and dominant STAT1 mutations, confer predisposition to mycobacterial disease in patients resistant to most viruses. By contrast, disorders of IFN-α/β and IFN-λ production, caused by UNC93B1 and TLR3 mutations, confer predisposition to herpes simplex encephalitis (HSE) in otherwise healthy patients. Consistently, patients with impaired responses to IFN-α/β, IFN-γ, and presumably IFN-λ (carrying recessive mutations in STAT1), or with impaired responses to IFN-α/β and impaired IFN-γ production (carrying mutations in TYK2), or with impaired production of IFN-α/β, IFN-γ, and IFN-λ (carrying specific mutations in NEMO), are vulnerable to mycobacterial and viral infections, including HSE. These experiments of nature suggest that the three types of IFNs play at least two different roles in host defense. IFN-γ is essential for anti-mycobacterial immunity, whereas IFN-α/β and IFN-λ are essential for anti-viral immunity. Future studies in humans aim to define the specific roles of IFN-α/β and IFN-λ types and individual molecules in host defense in natura.     

Dendritic cell‐based therapeutic vaccine elicits polyfunctional HIV‐specific T‐cell immunity associated with control of viral load

Efforts aimed at restoring robust immune responses limiting human immunodeficiency virus (HIV)‐1 replication therapeutically are warranted. We report that vaccination with dendritic cells generated ex vivo and loaded with HIV lipopeptides in patients (n = 19) on antiretroviral therapy was well tolerated and immunogenic. Vaccination increased: (i) the breadth of the immune response from 1 (1–3) to 4 (2–5) peptide‐pool responses/patient (p = 0.009); (ii) the frequency of functional T cells (producing at least two cytokines among IFN‐γ, TNF‐α, and IL‐2) from 0.026 to 0.32% (p = 0.002) and from 0.26 to 0.35% (p = 0.005) for CD4⁺ and CD8⁺ T cells, respectively; and (iii) the breadth of cytokines secreted by PBMCs upon antigen exposure, including IL‐2, IFN‐γ, IL‐21, IL‐17, and IL‐13. Fifty percent of patients experienced a maximum of viral load (VL) 1 log₁₀ lower than the other half following antiretroviral treatment interruption. An inverse correlation was found between the maximum of VL and the frequency of polyfunctional CD4⁺ T cells (p = 0.007), production of IL‐2 (p = 0.006), IFN‐γ (p = 0.01), IL‐21 (p = 0.006), and IL‐13 (p = 0.001). These results suggest an association between vaccine responses and a better control of viral replication. These findings will help in the development of strategies for a functional cure for HIV infection.