scholarly journals Specific CD4+T-Cell Reactivity and Cytokine Release in Different Clinical Presentations of Leptospirosis

2015 ◽  
Vol 22 (12) ◽  
pp. 1276-1284 ◽  
Author(s):  
Magdalena Sarah Volz ◽  
Verena Moos ◽  
Kristina Allers ◽  
Enno Luge ◽  
Anne Mayer-Scholl ◽  
...  

ABSTRACTClinical manifestations of leptospirosis are highly variable: from asymptomatic to severe and potentially fatal. The outcome of the disease is usually determined in the immunological phase, beginning in the second week of symptoms. The underlying mechanisms, predictive factors, and individual immune responses that contribute to clinical variations are not well understood. The aim of this study was to determine the specifics of CD4+T-cell reactivity and cytokine release after stimulation with leptospiral antigens in patients with leptospirosis of different disease severities (patients with mild and severe symptoms) and in control subjects (with and without proven exposure toLeptospira). Whole-blood specimens were stimulated withLeptospiraantigensin vitro. Subsequently, intracellular staining of cytokines was performed, and flow cytometry was used to assess the expression of CD40 ligand (CD40L) and the production of gamma interferon (IFN-γ), interleukin-10 (IL-10), IL-2, and tumor necrosis factor alpha (TNF-α) by CD4+T cells. The production of inflammatory cytokines such as TNF-α by CD4+T cells after stimulation with leptospiral antigens was highest in patients with severe disease. In contrast, the ratio of IL-10 production to TNF-α production was higher in exposed subjects than in patients with mild and severe disease. Levels of proinflammatory cytokines such as TNF-α may be useful markers of the severity of the immunological phase of leptospirosis. IL-10 production by T cells after antigen-specific stimulation may indicate a more successful downregulation of the inflammatory response and may contribute to an asymptomatic course of the disease.

2012 ◽  
Vol 81 (3) ◽  
pp. 740-752 ◽  
Author(s):  
Brian M. Gray ◽  
Clinton A. Fontaine ◽  
Sara A. Poe ◽  
Kathryn A. Eaton

ABSTRACTDisease due to the gastric pathogenHelicobacter pylorivaries in severity from asymptomatic to peptic ulcer disease and cancer. Accumulating evidence suggests that one source of this variation is an abnormal host response. The goal of this study was to use a mouse model ofH. pylorigastritis to investigate the roles of regulatory T cells (Treg) as well as proinflammatory T cells (Th1 and Th17) in gastritis, gastric T cell engraftment, and gastric cytokine production. Our results support published data indicating that severe gastritis in T cell recipient mice is due to failure of Treg engraftment, that Treg ameliorate gastritis, and that the proinflammatory response is attributable to interactions between several cell subsets and cytokines. We confirmed that gamma interferon (IFN-γ) is essential for induction of gastritis but showed that IFN-γ-producing CD4 T cells are not necessary. Interleukin 17A (IL-17A) also contributed to gastritis, but to a lesser extent than IFN-γ. Tumor necrosis factor alpha (TNF-α) and IL-17F were also elevated in association with disease. These results indicate that whileH. pylori-specific CD4+T cells and IFN-γ are both essential for induction of gastritis due toH. pylori, IFN-γ production by T cells is not essential. It is likely that other proinflammatory cytokines, such as IL-17F and TNF-α, shown to be elevated in this model, also contribute to the induction of disease. We suggest that gastritis due toH. pyloriis associated with loss of immunoregulation and alteration of several cytokines and cell subsets and cannot be attributed to a single immune pathway.


2014 ◽  
Vol 82 (9) ◽  
pp. 3775-3782 ◽  
Author(s):  
Lyticia A. Ochola ◽  
Cyrus Ayieko ◽  
Lily Kisia ◽  
Ng'wena G. Magak ◽  
Estela Shabani ◽  
...  

ABSTRACTIndividuals naturally exposed toPlasmodium falciparumlose clinical immunity after a prolonged lack of exposure.P. falciparumantigen-specific cytokine responses have been associated with protection from clinical malaria, but the longevity ofP. falciparumantigen-specific cytokine responses in the absence of exposure is not well characterized. A highland area of Kenya with low and unstable malaria transmission provided an opportunity to study this question. The levels of antigen-specific cytokines and chemokines associated in previous studies with protection from clinical malaria (gamma interferon [IFN-γ], interleukin-10 [IL-10], and tumor necrosis factor alpha [TNF-α]), with increased risk of clinical malaria (IL-6), or with pathogenesis of severe disease in malaria (IL-5 and RANTES) were assessed by cytometric bead assay in April 2008, October 2008, and April 2009 in 100 children and adults. During the 1-year study period, none had an episode of clinicalP. falciparummalaria. Two patterns of cytokine responses emerged, with some variation by antigen: a decrease at 6 months (IFN-γ and IL-5) or at both 6 and 12 months (IL-10 and TNF-α) or no change over time (IL-6 and RANTES). These findings document thatP. falciparumantigen-specific cytokine responses associated in prior studies with protection from malaria (IFN-γ, TNF-α, and IL-10) decrease significantly in the absence ofP. falciparumexposure, whereas those associated with increased risk of malaria (IL-6) do not. The study findings provide a strong rationale for future studies of antigen-specific IFN-γ, TNF-α, and IL-10 responses as biomarkers of increased population-level susceptibility to malaria after prolonged lack ofP. falciparumexposure.


Hepatology ◽  
2012 ◽  
Vol 55 (4) ◽  
pp. 1130-1138 ◽  
Author(s):  
Stephen M. Brindley ◽  
Allison M. Lanham ◽  
Frederick M. Karrer ◽  
Rebecca M. Tucker ◽  
Andrew P. Fontenot ◽  
...  

2008 ◽  
Vol 35 (11) ◽  
pp. 2220-2228 ◽  
Author(s):  
LIPING PANG ◽  
LISHA WANG ◽  
TALIN SUO ◽  
HUIQIN HAO ◽  
XIANFENG FANG ◽  
...  

ObjectiveTo study the effect of tumor necrosis factor-α (TNF-α) antagonist (etanercept) treatment on the peripheral T cell reactivity of patients with ankylosing spondylitis (AS).MethodsPeripheral blood mononuclear cells were collected from 40 patients with AS at baseline, after 2 and 6 weeks of etanercept treatment or placebo treatment, and from healthy controls. The number of cells secreting various cytokines was detected by enzyme linked immunospot. Serum soluble interleukin 2 (IL-2) receptor level was measured by ELISA. T cell proliferation was assayed with the WST-1 live cell-staining method. The myeloid dendritic cell (mDC) and regulatory T cell (Treg) levels were analyzed by fluorescence activated cell sorting.ResultsAfter 2 and 6 weeks of etanercept treatment, the number of TNF-α-secreting monocytes decreased. Although the T cell proliferation rate remained stable, the number of T cells secreting IL-2 and interferon-γ under anti-CD3/anti-CD28 stimulation was significantly decreased. The level of serum soluble IL-2R (sIL-2R), a T cell activation marker, also declined. The changes in T cell reactivity were correlated with a significant increase in MHC Class II-positive mDC cells in circulation. An increase in Treg cell numbers was also observed.ConclusionThe anti-TNF-α therapy blockaded MHC Class II-positive mDC maturation, enhanced regulatory T cell levels, and suppressed the functions of effector T cells. The reduced T cell reactivity could contribute to the efficacy of the TNF-α antagonist therapy in patients with AS.


2015 ◽  
Vol 83 (5) ◽  
pp. 2118-2126 ◽  
Author(s):  
Truc Hoang ◽  
Else Marie Agger ◽  
Joseph P. Cassidy ◽  
Jan P. Christensen ◽  
Peter Andersen

Protein energy malnutrition (PEM) increases susceptibility to infectious diseases, including tuberculosis (TB), but it is not clear how PEM influences vaccine-promoted immunity to TB. We demonstrate that PEM during low-level steady-state TB infection in a mouse model results in rapid relapse ofMycobacterium tuberculosis, as well as increased pathology, in bothMycobacterium bovisBCG-vaccinated and unvaccinated animals. PEM did not change the overall numbers of CD4 T cells in BCG-vaccinated animals but resulted in an almost complete loss of antigen-specific cytokine production. Furthermore, there was a change in cytokine expression characterized by a gradual loss of multifunctional antigen-specific CD4 T cells and an increased proportion of effector cells expressing gamma interferon and tumor necrosis factor alpha (IFN-γ+TNF-α+and IFN-γ+cells). PEM duringM. tuberculosisinfection completely blocked the protection afforded by the H56-CAF01 subunit vaccine, and this was associated with a very substantial loss of the interleukin-2-positive memory CD4 T cells promoted by this vaccine. Similarly, PEM during the vaccination phase markedly reduced the H56-CAF01 vaccine response, influencing all cytokine-producing CD4 T cell subsets, with the exception of CD4 T cells positive for TNF-α only. Importantly, this impairment was reversible and resupplementation of protein during infection rescued both the vaccine-promoted T cell response and the protective effect of the vaccine againstM. tuberculosisinfection.


2016 ◽  
Vol 23 (4) ◽  
pp. 282-293 ◽  
Author(s):  
Vijaya Satchidanandam ◽  
Naveen Kumar ◽  
Sunetra Biswas ◽  
Rajiv S. Jumani ◽  
Chandni Jain ◽  
...  

ABSTRACTWe previously reported that Rv1860 protein fromMycobacterium tuberculosisstimulated CD4+and CD8+T cells secreting gamma interferon (IFN-γ) in healthy purified protein derivative (PPD)-positive individuals and protected guinea pigs immunized with a DNA vaccine and a recombinant poxvirus expressing Rv1860 from a challenge with virulentM. tuberculosis. We now show Rv1860-specific polyfunctional T (PFT) cell responses in the blood of healthy latentlyM. tuberculosis-infected individuals dominated by CD8+T cells, using a panel of 32 overlapping peptides spanning the length of Rv1860. Multiple subsets of CD8+PFT cells were significantly more numerous in healthy latently infected volunteers (HV) than in tuberculosis (TB) patients (PAT). The responses of peripheral blood mononuclear cells (PBMC) from PAT to the peptides of Rv1860 were dominated by tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) secretions, the former coming predominantly from non-T cell sources. Notably, the pattern of the T cell response to Rv1860 was distinctly different from those of the widely studiedM. tuberculosisantigens ESAT-6, CFP-10, Ag85A, and Ag85B, which elicited CD4+T cell-dominated responses as previously reported in other cohorts. We further identified a peptide spanning amino acids 21 to 39 of the Rv1860 protein with the potential to distinguish latent TB infection from disease due to its ability to stimulate differential cytokine signatures in HV and PAT. We suggest that a TB vaccine carrying these and other CD8+T-cell-stimulating antigens has the potential to prevent progression of latentM. tuberculosisinfection to TB disease.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3436-3436 ◽  
Author(s):  
Simon Heidegger ◽  
Diana Kreppel ◽  
Michael Bscheider ◽  
Alexander Wintges ◽  
Sarah Bek ◽  
...  

Abstract Antibody-mediated targeting of regulatory T cell receptors such as CTLA-4 has been shown to enhance anti-tumor immune responses against several cancer entities including malignant melanoma. Yet, therapeutic success in patients remains variable underscoring the need for novel combinatorial approaches. Here we established a vaccination protocol that combines selective engagement of the nucleic acid-sensing pattern recognition receptor RIG-I, antigen and CTLA-4-blockade. We found that vaccination together with RIG-I ligation strongly synergized with CTLA-4 blockade to induce expansion and activation of antigen-specific CD8+ T cells and potent anti-tumor immunity. Cross-priming of cytotoxic T cells as well as anti-tumor immunity required the adapter protein MAVS and type I interferon (IFN) signaling and were mediated by dendritic cells. In addition, the benefit of the combined immunization with anti-CTLA-4 was reduced by systemic antibiotics pointing to the requisite of an intact commensal microbiota in this context. Together, our findings describe a novel combinatorial strategy that may form the basis for the design of new type I IFN-based regimens that enhance antigen-specific T cell reactivity against cancer. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2067-2067
Author(s):  
Muneyoshi Futami ◽  
Keisuke Suzuki ◽  
Satomi Kato ◽  
Yoshio Tahara ◽  
Yoichi Imai ◽  
...  

Cancer immunotherapy using chimeric antigen receptor-armed T cells (CAR-T cells) have shown excellent outcomes in hematological malignancies. However, cytokine release syndrome (CRS), characterized by excessive activation of CAR-T cells and macrophages remains to be overcome. Steroid administration usually resolves signs and symptoms of CRS but abrogates CAR-T cell expansion and persistence. Tocilizumab, a humanized monoclonal antibody against interleukin-6 receptor (IL-6R), attenuates CRS without significant loss of CAR-T cell activities, while perfect rescue of CRS symptoms cannot be achieved by IL-6/IL-6R blockade. There is actual need for novel strategies to prevent or cure CRS. TO-207, an N-benzoyl-L-phenylalanine derivative compound, significantly inhibits inflammatory cytokine production in a human monocyte/macrophage-specific manner. Here we tested TO-207 for its ability to inhibit cytokine production without impaired CAR-T cell function in a CRS-simulating co-culture system consisting of CAR-T cells, target leukemic cells and monocytes. To observe a precise pattern of cytokine release from CAR-T cells and monocytes, we first established a co-culture system that mimics CRS using K562/CD19 cells, 19-28z CAR-T cells, and peripheral blood CD14+ cells. IFN-γ was produced exclusively from CAR-T cells, and TNF-α, MIP-1α, M-CSF, and IL-6 were produced from both CAR-T cells and monocytes, but monocytes were the major source of these cytokine production. MCP-1, IL-1β, IL-8, and IL-10 were released exclusively from monocytes. To observe the effect of drugs on cytokine production, prednisolone (PSL), TO-207, tocilizumab, and anakinra (an IL-1R antagonist) were added to the co-culture. PSL exhibited suppressive effects on TNF-α and MCP-1 production. Tocilizumab did not suppress these cytokines. Anakinra up-regulated IL-6 and IL-1β production, probably due to activation of negative feedback loops. Interestingly, TO-207 widely suppressed all of these monocyte-derived cytokines including TNF-α, IL-6, IL-1β, MCP-1, IL-8, and GM-CSF. Next, we observed whether the cytokine inhibition by TO-207 attenuates killing effect of CAR-T cells. PSL attenuated killing effect of CD4+ CAR-T cells and CD8+ CAR-T cells toward K562/CD19 cells. In contrast, TO-207 did not exhibit any change in cytotoxicity of CD4+ CAR-T cells and CD8+ CAR-T cells. To determine whether the effect of PSL and TO-207 on cytotoxicity changes in the presence of CD14+ monocytes, CD14+ cells were added to the co-culture. In the absence of CAR-T cells, PSL induced a modest attenuation of cytotoxicity, whereas to the CAR-T cells, PSL exhibited a significant attenuation of cytotoxicity. TO-207 exhibited a minimal effect on cytotoxicity in the absence or presence of CAR-T cells. These results suggested that CAR-T cells play a major role in the cytotoxicity toward leukemia cells, and drugs that do not affect CAR-T cell functions, such as TO-207, maintain their cytotoxic effects on leukemia cells. In conclusion, our present co-culture model with K562/CD19 cells, 19-28z CAR-T cells, and CD14+ monocytes accurately recapitulate killing effect and cytokine release profiles. IFN-γ was produced exclusively by CAR-T cells, but majority of other cytokines such as TNF-α, MIP-1α, M-CSF, IL-6, MCP-1, IL-1β, IL-8, and IL-10 were from CD14+ monocytes/macrophages. Because killing effect was largely dependent on CAR-T cells while cytokine production was dependent on monocytes/macrophages, selective inhibition of pro-inflammatory cytokines from monocytes by TO-207 would be ideal for treatment of CAR-T-related CRS. These results encourage us to consider a clinical application for CRS. Figure Disclosures Futami: Torii Pharmaceutical: Research Funding. Suzuki:Torii Pharmaceutical: Employment. Kato:Torii Pharmmaceutical: Research Funding. Tahara:Torii Pharmaceutical: Employment. Imai:Celgene: Honoraria, Research Funding; Janssen Pharmaceutical K.K: Honoraria, Research Funding; Bristol-Myers Squibb: Research Funding. Mimura:Torii Pharmaceutical: Employment. Watanabe:Torii Pharmaceutical: Employment. Tojo:AMED: Research Funding; Torii Pharmaceutical: Research Funding.


2020 ◽  
Author(s):  
Gennadi V. Glinsky

AbstractSeveral recent studies identified SARS-CoV-2 reactive T cells in people without exposure to the virus. However, pathophysiological implications of these findings remain unknown. Here, the potential impact of pre-existing T cell reactivity against SARS-CoV-2 in uninfected individuals on markedly different COVID-19 mortality levels in different countries has been investigated. The inverse correlation is documented between the prevalence of pre-existing SARS-CoV-2 reactive T cells in people without exposure to the virus and COVID-19 mortality rates in different countries. In countries with similar levels of pre-existing SARS-CoV-2 cross-reactive T cells in uninfected individuals, differences in COVID-19 mortality appear linked with the extend and consistency of implementations of social measures designed to limit the transmission of SARS-CoV-2 (lockdown; physical distancing; mask wearing). Collectively, these observations support the model that the level of pre-existing SARS-CoV-2 reactive T cells is one of the important determinants of the innate herd immunity against COVID-19. Together with the consistent social measures directed to limit the virus spread, high levels of pre-existing SARS-CoV-2 reactive T cells appear significant determinants diminishing the COVID-19 mortality. Observations reported in this contribution should have significant impact on definitions of the herd immunity threshold required to effectively stop the pandemic in different countries across the globe.


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