Immunostimulatory Effects of Recombinant Erysipelothrix rhusiopathiae Expressing Porcine Interleukin-18 in Mice and Pigs

ABSTRACTInterleukin-18 (IL-18), which was originally called gamma interferon (IFN-γ)-inducing factor, has been shown to play an important role in innate and acquired immune responses. In this study, attenuatedErysipelothrix rhusiopathiaestrains were engineered to produce porcine IL-18 (poIL-18) and evaluated for their potential immunostimulatory effect in animals. Recombinant poIL-18 was successfully expressed in the recombinantE. rhusiopathiaestrains YS-1/IL-18 and KO/IL-18. The culture supernatant of YS-1/IL-18 was confirmed to induce IFN-γ production in murine splenocytesin vitro, and this production was inhibited by incubation with anti-poIL-18 monoclonal antibodies. Furthermore, more IFN-γ production was induced upon stimulation of splenocytes with concanavalin A for splenocytes from mice that were intraperitoneally inoculated with YS-1/IL-18 than for splenocytes from control mice inoculated with the parent strain YS-1. Peritoneal macrophages from mice preinoculated with YS-1/IL-18 exhibited enhanced phagocytosis ofSalmonella entericasubsp.entericaserovar Typhimurium compared with peritoneal macrophages from control mice preinoculated with YS-1. We also confirmed the immunostimulatory effect on humoral immune responses against antigens ofE. rhusiopathiaeandMycoplasma hyopneumoniaein gnotobiotic pigs that were orally preinoculated with KO/IL-18. Thus, these results provide evidence thatE. rhusiopathiaeis a promising vector for the expression of host cytokines and suggest the potential utility ofE. rhusiopathiaevector-encoded cytokines in the activation of host innate and acquired immune responses.

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The Life Cycle Stages of Pneumocystis murina Have Opposing Effects on the Immune Response to This Opportunistic Fungal Pathogen

Infection and Immunity ◽

10.1128/iai.00519-16 ◽

2016 ◽

Vol 84 (11) ◽

pp. 3195-3205 ◽

Cited By ~ 9

Author(s):

Heather M. Evans ◽

Grady L. Bryant ◽

Beth A. Garvy

Keyword(s):

Cell Wall ◽

Life Cycle ◽

Immune Responses ◽

Immune Cells ◽

Innate Immune ◽

Innate Immune Cells ◽

Content Type ◽

Life Cycle Stages ◽

Ifn Γ

The cell wall β-glucans of Pneumocystis cysts have been shown to stimulate immune responses in lung epithelial cells, dendritic cells, and alveolar macrophages. Little is known about how the trophic life forms, which do not have a fungal cell wall, interact with these innate immune cells. Here we report differences in the responses of both neonatal and adult mice to the trophic and cystic life cycle stages of Pneumocystis murina . The adult and neonatal immune responses to infection with Pneumocystis murina trophic forms were less robust than the responses to infection with a physiologically normal mixture of cysts and trophic forms. Cysts promoted the recruitment of nonresident innate immune cells and T and B cells into the lungs. Cysts, but not trophic forms, stimulated increased concentrations of the cytokine gamma interferon (IFN-γ) in the alveolar spaces and an increase in the percentage of CD4 + T cells that produce IFN-γ. In vitro , bone marrow-derived dendritic cells (BMDCs) stimulated with cysts produced the proinflammatory cytokines interleukin 1β (IL-1β) and IL-6. In contrast, trophic forms suppressed antigen presentation to CD4 + T cells, as well as the β-glucan-, lipoteichoic acid (LTA)-, and lipopolysaccharide (LPS)-induced production of interleukin 1β (IL-1β), IL-6, and tumor necrosis factor alpha (TNF-α) by BMDCs. The negative effects of trophic forms were not due to ligation of mannose receptor. Our results indicate that optimal innate and adaptive immune responses to Pneumocystis species are dependent on stimulation with the cyst life cycle stage. Conversely, trophic forms suppress β-glucan-induced proinflammatory responses in vitro , suggesting that the trophic forms dampen cyst-induced inflammation in vivo .

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Impact of Malaria Preexposure on Antiparasite Cellular and Humoral Immune Responses after Controlled Human Malaria Infection

Infection and Immunity ◽

10.1128/iai.03069-14 ◽

2015 ◽

Vol 83 (5) ◽

pp. 2185-2196 ◽

Cited By ~ 26

Author(s):

Joshua M. Obiero ◽

Seif Shekalaghe ◽

Cornelus C. Hermsen ◽

Maxmillian Mpina ◽

Else M. Bijker ◽

...

Keyword(s):

Immune Responses ◽

Intradermal Injection ◽

Content Type ◽

Human Malaria ◽

Humoral Immune ◽

Humoral Immune Responses ◽

Controlled Human Malaria Infection ◽

Circulating Lymphocytes ◽

Ifn Γ

To understand the effect of previous malaria exposure on antiparasite immune responses is important for developing successful immunization strategies. Controlled human malaria infections (CHMIs) using cryopreservedPlasmodium falciparumsporozoites provide a unique opportunity to study differences in acquisition or recall of antimalaria immune responses in individuals from different transmission settings and genetic backgrounds. In this study, we compared antiparasite humoral and cellular immune responses in two cohorts of malaria-naive Dutch volunteers and Tanzanians from an area of low malarial endemicity, who were subjected to the identical CHMI protocol by intradermal injection ofP. falciparumsporozoites. Samples from both trials were analyzed in parallel in a single center to ensure direct comparability of immunological outcomes. Within the Tanzanian cohort, we distinguished one group with moderate levels of preexisting antibodies to asexualP. falciparumlysate and another that, based onP. falciparumserology, resembled the malaria-naive Dutch cohort. PositiveP. falciparumserology at baseline was associated with a lower parasite density at first detection by quantitative PCR (qPCR) after CHMI than that for Tanzanian volunteers with negative serology. Post-CHMI, both Tanzanian groups showed a stronger increase in anti-P. falciparumantibody titers than Dutch volunteers, indicating similar levels of B-cell memory independent of serology. In contrast to the Dutch, Tanzanians failed to increaseP. falciparum-specificin vitrorecall gamma interferon (IFN-γ) production after CHMI, and innate IFN-γ responses were lower inP. falciparumlysate-seropositive individuals than in seronegative individuals. In conclusion, positiveP. falciparumlysate serology can be used to identify individuals with better parasite control but weaker IFN-γ responses in circulating lymphocytes, which may help to stratify volunteers in future CHMI trials in areas where malaria is endemic.

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Interleukin-18 Is Critical for Mucosa-Associated Invariant T Cell Gamma Interferon Responses toFrancisellaSpeciesIn Vitrobut NotIn Vivo

Infection and Immunity ◽

10.1128/iai.00117-18 ◽

2018 ◽

Vol 86 (5) ◽

Cited By ~ 13

Author(s):

Eric Jesteadt ◽

Irma Zhang ◽

Huifeng Yu ◽

Anda Meierovics ◽

Wei-Jen Chua Yankelevich ◽

...

Keyword(s):

Pulmonary Infection ◽

Gamma Interferon ◽

Interleukin 18 ◽

Class I Mhc ◽

Content Type ◽

Mait Cells ◽

Ifn Γ ◽

Mait Cell

ABSTRACTMucosa-associated invariant T (MAIT) cells are a subset of innate T cells that express a semi-invariant Vα chain paired with limited Vβ chains. MAIT cells are activated by riboflavin metabolite derivatives presented by the nonpolymorphic major histocompatibility complex class I (MHC-I)-like molecule MR1. The precise mechanisms required to activate MAIT cells are an area of intense interest. Here we used two closely related intracellular pathogens with distinct inflammasome activation phenotypes to probe the role of innate cytokines in MAIT cell activation. Using anin vitroassay containing transgenic murine MAIT cells, we show that macrophages infected withFrancisella novicida, a strong inflammasome activator, released high levels of interleukin-18 (IL-18) and stimulated high levels of MAIT cell gamma interferon (IFN-γ) through a partially MR1-independent pathway. In contrast, macrophages infected withFrancisella tularensislive vaccine strain (LVS), a weak inflammasome activator, generated little IL-18 and stimulated low MAIT cell IFN-γ through an MR1-dependent pathway. By manipulating the quantities of IL-18 in these cultures, we show that the IL-18 concentration is sufficient to influence the magnitude of MAIT cell IFN-γ production. Correspondingly, infected IL-18-deficient macrophages failed to induce substantial MAIT cell IFN-γ. In contrast, we found that MAIT cell IFN-γ production in the lungs of IL-18-deficient mice was not significantly different from that in WT mice duringF. tularensisLVS pulmonary infection. Overall, we demonstrate that while IL-18 is essential for the MAIT cell IFN-γ responsein vitro, it is not essential for MAIT cell IFN-γ production duringin vivoLVS pulmonary infection, suggesting that additional signals can drive MAIT cell IFN-γ productionin vivo.

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Activities of Murine Peripheral Blood Lymphocytes Provide Immune Correlates That Predict Francisella tularensis Vaccine Efficacy

Infection and Immunity ◽

10.1128/iai.01348-15 ◽

2016 ◽

Vol 84 (4) ◽

pp. 1054-1061 ◽

Cited By ~ 10

Author(s):

Roberto De Pascalis ◽

Lara Mittereder ◽

Nikki J. Kennett ◽

Karen L. Elkins

Keyword(s):

Gene Expression ◽

Immune Responses ◽

Francisella Tularensis ◽

Peripheral Blood ◽

Vaccine Efficacy ◽

Murine Splenocytes ◽

Content Type ◽

Correlates Of Protection ◽

Immune Correlates

We previously identified potential correlates of vaccine-induced protection againstFrancisella tularensisusing murine splenocytes and further demonstrated that the relative levels of gene expression varied significantly between tissues. In contrast to splenocytes, peripheral blood leukocytes (PBLs) represent a means to bridge vaccine efficacy in animal models to that in humans. Here we take advantage of this easily accessible source of immune cells to investigate cell-mediated immune responses against tularemia, whose sporadic incidence makes clinical trials of vaccines difficult. Using PBLs from mice vaccinated withF. tularensisLive Vaccine Strain (LVS) and related attenuated strains, we combined the control ofin vitroFrancisellareplication within macrophages with gene expression analyses. Thein vitrofunctions of PBLs, particularly the control of intramacrophage LVS replication, reflected the hierarchy ofin vivoprotection conferred by LVS-derived vaccines. Moreover, several genes previously identified by the evaluation of splenocytes were also found to be differentially expressed in immune PBLs. In addition, more extensive screening identified additional potential correlates of protection. Finally, expression of selected genes in mouse PBLs obtained shortly after vaccination, withoutex vivorestimulation, was different among vaccine groups, suggesting a potential tool to monitor efficacious vaccine-induced immune responses againstF. tularensis. Our studies demonstrate that murine PBLs can be used productively to identify potential correlates of protection againstF. tularensisand to expand and refine a comprehensive set of protective correlates.

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Enhancement of Neutrophil Function by Interleukin-18 Therapy Protects Burn-Injured Mice from Methicillin-Resistant Staphylococcus aureus

Infection and Immunity ◽

10.1128/iai.01298-10 ◽

2011 ◽

Vol 79 (7) ◽

pp. 2670-2680 ◽

Cited By ~ 29

Author(s):

Manabu Kinoshita ◽

Hiromi Miyazaki ◽

Satoshi Ono ◽

Akihito Inatsu ◽

Hiroyuki Nakashima ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Burn Injury ◽

Neutrophil Function ◽

Scid Mice ◽

Interleukin 18 ◽

Methicillin Resistant ◽

Content Type ◽

Mrsa Infection ◽

Ifn Γ

ABSTRACTMethicillin-resistantStaphylococcus aureus(MRSA) infection is a grave concern in burn-injured patients. We investigated the efficacy of interleukin-18 (IL-18) treatment in postburn MRSA infection. Alternate-day injections of IL-18 into burn-injured C57BL/6 mice significantly increased their survival after MRSA infection and after methicillin-sensitiveS. aureusinfection. Although IL-18 treatment of burn-injured mice augmented natural IgM production before MRSA infection and gamma interferon (IFN-γ) production after MRSA infection, neither IgM nor IFN-γ significantly contributed to the improvement in mouse survival. IL-18 treatment increased/restored the serum tumor necrosis factor (TNF), IL-17, IL-23, granulocyte colony-stimulating factor (G-CSF), and macrophage inflammatory protein (MIP-2) levels, as well as the neutrophil count, after MRSA infection of burn-injured mice; it also improved impaired neutrophil functions, phagocytic activity, production of reactive oxygen species, and MRSA-killing activity. However, IL-18 treatment was ineffective against MRSA infection in both burn- and sham-injured neutropenic mice. Enhancement of neutrophil functions by IL-18 was also observedin vitro. Furthermore, when neutrophils from IL-18-treated burn-injured mice were adoptively transferred into nontreated burn-injured mice 2 days after MRSA challenge, survival of the recipient mice increased. NOD-SCID mice that have functionally intact neutrophils and macrophages (but not T, B, or NK cells) were substantially resistant to MRSA infection. IL-18 treatment increased the survival of NOD-SCID mice after burn injury and MRSA infection. An adoptive transfer of neutrophils using NOD-SCID mice also showed a beneficial effect of IL-18-activated neutrophils, similar to that seen in C57BL/6 mice. Thus, although neutrophil functions were impaired in burn-injured mice, IL-18 therapy markedly activated neutrophil functions, thereby increasing survival from postburn MRSA infection.

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Retrospective Performance Analyses of over Two Million U.S. QuantiFERON Blood Sample Results

Microbiology Spectrum ◽

10.1128/spectrum.00096-21 ◽

2021 ◽

Author(s):

Caixia Bi ◽

Richard B. Clark ◽

Ronald Master ◽

Hema Kapoor ◽

Martin H. Kroll ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Immune Responses ◽

Blood Sample ◽

Interferon Gamma ◽

Performance Data ◽

Content Type ◽

Test Systems ◽

Ifn Γ ◽

Performance Analyses

Both the QuantiFERON-TB Gold Plus (QFT-Plus) and the QuantiFERON-TB Gold In-Tube (QFT-GIT) tests are interferon gamma (IFN-γ) release assays (IGRAs) intended to detect in vitro cell-mediated immune responses to Mycobacterium tuberculosis antigens. In this study, we retrospectively analyzed performance data for both the QFT-GIT and QFT-Plus test systems from over 2 million samples.

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Oxidative Stress Compromises Lymphocyte Function in Neonatal Dairy Calves

Antioxidants ◽

10.3390/antiox10020255 ◽

2021 ◽

Vol 10 (2) ◽

pp. 255

Author(s):

Wilmer Cuervo ◽

Lorraine M. Sordillo ◽

Angel Abuelo

Keyword(s):

Oxidative Stress ◽

Immune Responses ◽

Immune Cell ◽

Lymphocyte Activation ◽

Dairy Calves ◽

Lymphocyte Function ◽

Newborn Calves ◽

Ifn Γ ◽

The Impact

Dairy calves are unable to mount an effective immune response during their first weeks of life, which contributes to increased disease susceptibility during this period. Oxidative stress (OS) diminishes the immune cell capabilities of humans and adult cows, and dairy calves also experience OS during their first month of life. However, the impact that OS may have on neonatal calf immunity remains unexplored. Thus, we aimed to evaluate the impact of OS on newborn calf lymphocyte functions. For this, we conducted two experiments. First, we assessed the association of OS status throughout the first month of age and the circulating concentrations of the cytokines interferon-gamma (IFN-γ) and interleukin (IL) 4, as well as the expression of cytokine-encoding genes IFNG, IL2, IL4, and IL10 in peripheral mononuclear blood cells (PBMCs) of 12 calves. Subsequently, we isolated PBMCs from another 6 neonatal calves to investigate in vitro the effect of OS on immune responses in terms of activation of lymphocytes, cytokine expression, and antibody production following stimulation with phorbol 12-myristate 13-acetate or bovine herpesvirus-1. The results were compared statistically through mixed models. Calves exposed to high OS status in their first month of age showed higher concentrations of IL-4 and expression of IL4 and IL10 and lower concentrations of IFN-γ and expression of IFNG and IL2 than calves exposed to lower OS. In vitro, OS reduced lymphocyte activation, production of antibodies, and protein and gene expression of key cytokines. Collectively, our results demonstrate that OS can compromise some immune responses of newborn calves. Hence, further studies are needed to explore the mechanisms of how OS affects the different lymphocyte subsets and the potential of ameliorating OS in newborn calves as a strategy to augment the functional capacity of calf immune cells, as well as enhance calves’ resistance to infections.

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Effect ofTityus serrulatusvenom on cytokine production and the activity of murine macrophages

Mediators of Inflammation ◽

10.1080/09629350210308 ◽

2002 ◽

Vol 11 (1) ◽

pp. 23-31 ◽

Cited By ~ 27

Author(s):

Vera L. Petricevich

Keyword(s):

Cytokine Production ◽

Peritoneal Macrophages ◽

Interferon Γ ◽

Enzyme Linked Immunosorbent Assay ◽

No Production ◽

Dependent Manner ◽

Immune Functions ◽

Macrophage Activity ◽

Ifn Γ

The purpose of this study was to investigate the effects ofTityus serrulatusvenom (TSV) on murine peritoneal macrophages evaluated in terms of activation. The effects of crude TSV were analysed by detection of cytokines, oxygen intermediate metabolites (H2O2) and nitric oxide (NO) in supernatants of peritoneal macrophages. Several functional bioassays were employed including anin vitromodel for envenomating: cytotoxicity of TSV was assessed using the lyses percentage. Tumor necrosis factor (TNF) activity was assayed by measuring its cytotoxic activity on L-929 cells, and interleukin-6 (IL-6) and interferon-γ (IFN-γ) were assayed by enzyme-linked immunosorbent assay, whereas NO levels were detected by Griess colorimetric reactions in culture supernatant of macrophages incubated with TSV and subsequently exposed to either lipopolysaccharide or IFN-γ. Incubation of macrophages with TSV increased production of IL-6 and IFN-γ in a dose-dependent manner. TNF production was not detected in supernatants treated with TSV at any concentration. The increase in IL-6 secretion was not associated with concentration-dependent cytoxicity of TSV on these cells. These data suggest that the cytotoxicity does not appear to be the main cause of an increased cytokine production by these cells. Although NO is an important effector molecule in macrophage microbicidal activity, the inducing potential of the test compounds for its release was found to be very moderate, ranging from 125 to 800 mM. Interestingly, NO levels of peritoneal macrophages were increased after IFN-γ. Moreover, NO production had an apparent effect on macrophage activity. The results obtained here also shown that the TSV induces an important elevation in H2O2release. These results combined with NO production suggest that TSV possesses significant immunomodulatory activities capable of stimulating immune functionsin vitro.

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Evaluation of Immunostimulatory Activities of Synthetic Mannose-Containing Structures Mimicking the β-(1→2)-Linked Cell Wall Mannans of Candida albicans

Clinical and Vaccine Immunology ◽

10.1128/cvi.00298-12 ◽

2012 ◽

Vol 19 (11) ◽

pp. 1889-1893 ◽

Cited By ~ 14

Author(s):

Kaarina Ranta ◽

Kaisa Nieminen ◽

Filip S. Ekholm ◽

Moniká Poláková ◽

Mattias U. Roslund ◽

...

Keyword(s):

Candida Albicans ◽

Mononuclear Cells ◽

Human Peripheral Blood ◽

Peripheral Blood Mononuclear ◽

Content Type ◽

Mouse Macrophages ◽

Ifn Γ ◽

Low Levels ◽

Necrosis Factor

ABSTRACTImmunostimulatory properties of synthetic structures mimicking the β-(1→2)-linked mannans ofCandida albicanswere evaluatedin vitro. Contrary to earlier observations, tumor necrosis factor (TNF) production was not detected after stimulation with mannotetraose in mouse macrophages. Divalent disaccharide 1,4-bis(α-d-mannopyranosyloxy)butane induced TNF and some molecules induced low levels of gamma interferon (IFN-γ) in human peripheral blood mononuclear cells (PBMC).

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Leishmanicidal Activity of Isoselenocyanate Derivatives

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00904-18 ◽

2018 ◽

Vol 63 (2) ◽

pp. e00904-18 ◽

Cited By ~ 3

Author(s):

Celia Fernández-Rubio ◽

Esther Larrea ◽

José Peña Guerrero ◽

Eduardo Sesma Herrero ◽

Iñigo Gamboa ◽

...

Keyword(s):

Cell Cycle ◽

Amphotericin B ◽

Cell Cycle Progression ◽

Leishmania Major ◽

Antitumor Agents ◽

Peritoneal Macrophages ◽

Reference Drug ◽

Content Type ◽

Leishmanicidal Activity

ABSTRACTConventional chemotherapy against leishmaniasis includes agents exhibiting considerable toxicity. In addition, reports of drug resistance are not uncommon. Thus, safe and effective therapies are urgently needed. Isoselenocyanate compounds have recently been identified with potential antitumor activity. It is well known that some antitumor agents demonstrate effects againstLeishmania. In this study, thein vitroleishmanicidal activities of several organo-selenium and organo-sulfur compounds were tested againstLeishmania majorandLeishmania amazonensisparasites, using promastigotes and intracellular amastigote forms. The cytotoxicity of these agents was measured in murine peritoneal macrophages and their selectivity indexes were calculated. One of the tested compounds, the isoselenocyanate derivative NISC-6, showed selectivity indexes 2- and 10-fold higher than those of the reference drug amphotericin B when evaluated inL. amazonensisandL. major, respectively. The American strain (L. amazonensis) was less sensitive to NISC-6 thanL. major, showing a trend similar to that observed previously for amphotericin B. In addition, we also observed that NISC-6 significantly reduced the number of amastigotes per infected macrophage. On the other hand, we showed that NISC-6 decreases expression levels ofLeishmaniagenes involved in the cell cycle, such astopoisomerase-2(TOP-2),PCNA, andMCM4, therefore contributing to its leishmanicidal activity. The effect of this compound on cell cycle progression was confirmed by flow cytometry. We observed a significant increase of cells in the G1phase and a dramatic reduction of cells in the S phase compared to untreated cells. Altogether, our data suggest that the isoselenocyanate NISC-6 may be a promising candidate for new drug development against leishmaniasis.

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