scholarly journals The mouse lung early cellular innate immune response is not sufficient to control fungal infection with Cryptococcus neoformans

2019 ◽  
Author(s):  
Jacob Rudman ◽  
Helen Maria Marriott ◽  
Leo M. Carlin ◽  
Simon Andrew Johnston
Keyword(s):  
Immune Response ◽  
Cryptococcus Neoformans ◽  
Post Infection ◽  
Opportunistic Infections ◽  
Ex Vivo ◽  
Mouse Lung ◽  
Cell Mediated Immunity ◽  
Wide Field ◽  
Cryptococcal Infection

AbstractCryptococcus neoformanscauses life-threatening infection in the immunocompromised. This and other opportunistic pathogens are an increasing threat as immunosuppression increases globally. To counter antibiotic resistance, there is precedent for developing immune enhancing therapy. However, our understanding of how immunocompetent patients resolve these infections is poor as opportunistic infections typically resolve subclinically. Because this has led to a lack of clinical data, we rely on animal models. Currentin vivoinfection models either lack mammalian immunity or are not compatible with long term high content imaging required to model the complexities of human host-pathogen interactions. Therefore, we have developed anex vivomurine precision cut lung slice (PCLS) model to understand innate immunity in cryptococcosis. C57BL/6 mice were sacrificed 0 or 24 hours post infection withKN99αcryptococci. Lungs were inflated with 37°C agarose, 300μm thick PCLS were prepared on a vibratome and imaged by confocal or wide-field fluorescence microscopy. Using PCLS and immunofluorescence, we demonstrate cryptococcal replication and clearance rates are balanced over the first 24 hours of infection. Cell-mediated immunity is alveolar macrophage centric, although alveolar macrophages demonstrate limited phagocytosis of cryptococci and enable intracellular cryptococcal replication.Cryptococcus neoformansresponded to the lung environment by forming enlarged cells, although these were not large enough to be titan cells. To further understand cryptococcal proliferationin vivo, we also infected animals withplb1mutantCryptococcus neoformansthat has been shown to exhibit proliferation defectsin vivo. We found no difference in fungal burden withplb1infected animals 24 hours post infection, but observed significantly larger fungal cells and no incidences of phagocytosis. Thus, the PCLS model can be used to assess the lung immune response early in cryptococcal infection, demonstrating that resident lung macrophages cannot control cryptococcal infection and offer an intracellular niche forCryptococcus neoformansgrowth.

scholarly journals Melanization of Cryptococcus neoformans Affects Lung Inflammatory Responses during Cryptococcal Infection

2005 ◽  
Vol 73 (4) ◽  
pp. 2012-2019 ◽  
Author(s):  
Aron J. Mednick ◽  
Joshua D. Nosanchuk ◽  
Arturo Casadevall
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Cryptococcus Neoformans ◽  
Inflammatory Responses ◽  
Interleukin 4 ◽  
Additional Mechanism ◽  
Cryptococcal Infection ◽  
Immunomodulatory Properties ◽  
Oxidative Attack

ABSTRACT The production of melanin pigments is associated with virulence for many microbes. Melanin is believed to contribute to microbial virulence by protecting microbial cells from oxidative attack during infection. However, there is also evidence from various systems that melanins have immunomodulatory properties, which conceivably could contribute to virulence by altering immune responses. To investigate the effect of melanin on the immune response, we compared the murine pulmonary responses to infection with melanized and nonmelanized Cryptococcus neoformans cells. Infection with melanized cells resulted in a greater fungal burden during the early stages of infection and was associated with higher levels of interleukin-4 and MCP-1 and greater numbers of infiltrating leukocytes. Infection with laccase-positive (melanotic) C. neoformans cells also elicited higher MCP-1 levels and more infiltrating leukocytes than did infection with laccase-negative cells. Melanization interfered with phagocytosis in vivo for encapsulated C. neoformans but not for nonencapsulated cells. The results provide strong evidence that cryptococcal melanization can influence the immune response to infection and suggest that immunomodulation is an additional mechanism by which the pigment contributes to virulence.

scholarly journals In Vivo Role of Dendritic Cells in a Murine Model of Pulmonary Cryptococcosis

2006 ◽  
Vol 74 (7) ◽  
pp. 3817-3824 ◽  
Author(s):  
Karen L. Wozniak ◽  
Jatin M. Vyas ◽  
Stuart M. Levitz
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell Activation ◽  
Cell Activation ◽  
Ex Vivo ◽  
Interleukin 2 ◽  
Mouse Lung

ABSTRACT Dendritic cells (DC) have been shown to phagocytose and kill Cryptococcus neoformans in vitro and are believed to be important for inducing protective immunity against this organism. Exposure to C. neoformans occurs mainly by inhalation, and in this study we examined the in vivo interactions of C. neoformans with DC in the lung. Fluorescently labeled live C. neoformans and heat-killed C. neoformans were administered intranasally to C57BL/6 mice. At specific times postinoculation, mice were sacrificed, and lungs were removed. Single-cell suspensions of lung cells were prepared, stained, and analyzed by microscopy and flow cytometry. Within 2 h postinoculation, fluorescently labeled C. neoformans had been internalized by DC, macrophages, and neutrophils in the mouse lung. Additionally, lung DC from mice infected for 7 days showed increased expression of the maturation markers CD80, CD86, and major histocompatibility complex class II. Finally, ex vivo incubation of lung DC from infected mice with Cryptococcus-specific T cells resulted in increased interleukin-2 production compared to the production by DC from naïve mice, suggesting that there was antigen-specific T-cell activation. This study demonstrated that DC in the lung are capable of phagocytosing Cryptococcus in vivo and presenting antigen to C. neoformans-specific T cells ex vivo, suggesting that these cells have roles in innate and adaptive pulmonary defenses against cryptococcosis.

scholarly journals PD-L1 Checkpoint Blockade Augments Anti-Tumor Immune Response of GD2 or HER2-Bsab Ex Vivo Armed T-Cells (EVAT) Therapy in Osteosarcoma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1959-1959
Author(s):  
Jeong A Park ◽  
Hong fen Guo ◽  
Hong Xu ◽  
Nai-Kong V. Cheung
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Immune Checkpoint ◽  
Bispecific Antibody ◽  
Ex Vivo ◽  
Activated T Cells ◽  
The Impact ◽  
Anti Tumor Activity

Background Ex Vivo Armed T-cells (EVAT) carrying zeptomoles (10-21M) of T-cell engaging GD2-bispecific antibody (GD2-EVAT) or HER2-bispecific antibodies (HER2-EVAT) have potent anti-tumor activity against GD2(+) and/or HER2(+) solid tumors. Strategies to further optimize this approach are highly relevant. PD-1 is a key immune checkpoint receptor expressed mainly by activated T-cells and mediates immune suppression by binding to its ligands PD-L1 or PD-L2. Upregulation of PD-L1 has been found in many cancers including osteosarcoma and associated with aggressive disease and poor outcome. While the use of immune checkpoint inhibitors (ICIs) seems logical, the ideal timing when combined with T-cell engaging bispecific antibody (T-BsAb) or EVAT has yet to be defined. Here, we described the effects of anti-PD-1 or anti-PD-L1 antibodies on GD2-EVAT or HER2-EVAT therapy and explored the impact of its timing in the treatment of osteosarcoma which is GD2(+), HER2(+) and PD-L1(+). Methods GD2-BsAb and HER-BsAb were built using the IgG(L)-scFv format (Can Immunol Res, 3:266, 2015, Oncoimmunology, PMID:28405494). T-cells from healthy volunteer donors were isolated, and cultured ex vivo in the presence of CD3/CD28 beads plus 30 IU/mL of interleukin 2 (IL-2). Between day 7 and day 14, activated T-cells (ATCs) were harvested and armed for 20 minutes at room temperature with GD2-BsAb or HER2-BsAb. In vivo anti-tumor activity against GD2(+), HER2(+), and PD-L1(+) osteosarcoma cell line xenografts was tested in BALB-Rag2-/-IL-2R-γc-KO mice. Anti-human PD-1 antibody (pembrolizumab, anti-PD-1) or anti-human PD-L1 antibody (atezolizumab, anti-PD-L1) were tested for synergy with GD2-EVAT or HER2-EVAT therapy. Results The PD-1 expression increased among T-cells that circulated in the blood, that infiltrated the spleen or the tumor after EVAT therapy. While anti-PD-L1 combination therapy with GD2-EVAT or HER2-EVAT improved anti-tumor response against osteosarcoma (P=0.0123 and P=0.0004), anti-PD-1 did not (all P>0.05). The addition of anti-PD-L1 significantly increased T-cell survival in blood and T-cell infiltration of tumor when compared to GD2-EVAT or HER2-EVAT alone (all P<0.0001). Treatment of GD2-EVAT or anti-PD-L1 plus GD2-EVAT downregulated GD2 expression on tumors, but anti-PD-1 plus GD2-EVAT did not. For the next step we tested the impact of different combination schedules of ICIs on GD2-EVAT therapy. Concurrent anti-PD-1 (6 doses along with GD2-EVAT therapy) interfered with GD2-EVAT, while sequential anti-PD-1 (6 doses after GD2-EVAT) did not make a significant effect (P>0.05). On the other hand, while the concurrent use of anti-PD-L1 did not show benefit on GD2-EVAT, sequentially administered anti-PD-L1 produced a significant improvement in tumor control when compared to anti-PD-L1 or GD2-EVAT alone (P=0.002 and P=0.018). When anti-PD-L1 treatment was extended (12 doses after GD2-EVAT), the anti-tumor effect was most pronounced compared to GD2-EVAT alone (P <0.0001), which translated into improved survival (P=0.0057). These in vivo anti-tumor responses were associated with increased CD8(+) tumor infiltrating lymphocytes (TILs) of tumor. Conclusion In the arming platform, large numbers of target-specific T-cells can be generated, and this EVAT therapy is a highly effective cellular treatment with high potency in preclinical models. In addition, the advantage of ex vivo cytokine release following T-cell arming and activation could reduce or avoid life threatening cytokine storm if such activation was to proceed in vivo. Adoptive T-cell therapy induced immune response upregulates the inhibitory immune checkpoint PD-1/PD-L1 pathway, and combination treatment with anti-PD-L1 antibody, especially when combined as sequential therapy and continuously treated, significantly improved anti-tumor effect of EVAT, partly through increase in CD8(+) TILs infiltration. Disclosures Xu: MSK: Other: co-inventors in patents on GD2 bispecific antibody and HER2 bispecific antibody. Cheung:Ymabs: Patents & Royalties, Research Funding.

scholarly journals The Diverse Potential of Gluten from Different Durum Wheat Varieties in Triggering Celiac Disease: A Multilevel In Vitro, Ex Vivo and In Vivo Approach

Nutrients ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3566
Author(s):  
Federica Gaiani ◽  
Sara Graziano ◽  
Fatma Boukid ◽  
Barbara Prandi ◽  
Lorena Bottarelli ◽  
...  
Keyword(s):  
Immune Response ◽  
Celiac Disease ◽  
Durum Wheat ◽  
Ex Vivo ◽  
Diet Group ◽  
Control Group ◽  
Wheat Varieties ◽  
Before And After

The reasons behind the increasing prevalence of celiac disease (CD) worldwide are still not fully understood. This study adopted a multilevel approach (in vitro, ex vivo, in vivo) to assess the potential of gluten from different wheat varieties in triggering CD. Peptides triggering CD were identified and quantified in mixtures generated from simulated gastrointestinal digestion of wheat varieties (n = 82). Multivariate statistics enabled the discrimination of varieties generating low impact on CD (e.g., Saragolla) and high impact (e.g., Cappelli). Enrolled subjects (n = 46) were: 19 healthy subjects included in the control group; 27 celiac patients enrolled for the in vivo phase. Celiacs were divided into a gluten-free diet group (CD-GFD), and a GFD with Saragolla-based pasta group (CD-Sar). The diet was followed for 3 months. Data were compared between CD-Sar and CD-GFD before and after the experimental diet, demonstrating a limited ability of Saragolla to trigger immunity, although not comparable to a GFD. Ex vivo studies showed that Saragolla and Cappelli activated immune responses, although with great variability among patients. The diverse potential of durum wheat varieties in triggering CD immune response was demonstrated. Saragolla is not indicated for celiacs, yet it has a limited potential to trigger adverse immune response.

scholarly journals The Characterization of chIFITMs in Avian Coronavirus Infection In Vivo, Ex Vivo and In Vitro

Genes ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 918
Author(s):  
Angela Steyn ◽  
Sarah Keep ◽  
Erica Bickerton ◽  
Mark Fife
Keyword(s):  
Post Infection ◽  
Viral Infections ◽  
Ex Vivo ◽  
Large Family ◽  
Respiratory Pathogen ◽  
Restriction Factors ◽  
Respiratory Illnesses ◽  
Bird Mortality

The coronaviruses are a large family of enveloped RNA viruses that commonly cause gastrointestinal or respiratory illnesses in the infected host. Avian coronavirus infectious bronchitis virus (IBV) is a highly contagious respiratory pathogen of chickens that can affect the kidneys and reproductive systems resulting in bird mortality and decreased reproductivity. The interferon-inducible transmembrane (IFITM) proteins are activated in response to viral infections and represent a class of cellular restriction factors that restrict the replication of many viral pathogens. Here, we characterize the relative mRNA expression of the chicken IFITM genes in response to IBV infection, in vivo, ex vivo and in vitro using the pathogenic M41-CK strain, the nephropathogenic QX strain and the nonpathogenic Beaudette strain. In vivo we demonstrate a significant upregulation of chIFITM1, 2, 3 and 5 in M41-CK- and QX-infected trachea two days post-infection. In vitro infection with Beaudette, M41-CK and QX results in a significant upregulation of chIFITM1, 2 and 3 at 24 h post-infection. We confirmed a differential innate response following infection with distinct IBV strains and believe that our data provide new insights into the possible role of chIFITMs in early IBV infection.

Relationship of in vivo and ex vivo levels of TH1 and TH2 cytokines with viremia in HAART patients with and without opportunistic infections

2006 ◽  
Vol 78 (4) ◽  
pp. 431-439 ◽  
Author(s):  
Sardar Sindhu ◽  
Emil Toma ◽  
Paulo Cordeiro ◽  
Rasheed Ahmad ◽  
Richard Morisset ◽  
...  
Keyword(s):  
Opportunistic Infections ◽  
Ex Vivo ◽  
Th2 Cytokines ◽  
Th1 And Th2 Cytokines ◽  
Relationship Of ◽  
Th1 And Th2

scholarly journals Role of Mannoprotein in Induction and Regulation of Immunity to Cryptococcus neoformans

2001 ◽  
Vol 69 (5) ◽  
pp. 2808-2814 ◽  
Author(s):  
Donatella Pietrella ◽  
Robert Cherniak ◽  
Carla Strappini ◽  
Stefano Perito ◽  
Paolo Mosci ◽  
...  
Keyword(s):  
Immune Response ◽  
Cryptococcus Neoformans ◽  
Biological Significance ◽  
Rational Approach ◽  
Interleukin 12 ◽  
Effector Cells ◽  
Splenic Macrophages ◽  
The Brain

ABSTRACT Our previous observations showed that mannoprotein (MP) induces early and massive production of interleukin-12 (IL-12) in vitro. This study was designed to investigate whether this phenomenon could be applied in vivo and to determine the biological significance of MP inCryptococcus neoformans infection. The results reported here show that MP treatment induces IL-12 secretion by splenic macrophages and IL-12 p40 mRNA in the brain. During C. neoformans infection, MP reinforced IL-12 and IFN-γ secretion that coincided with enhanced antifungal activity of natural effector cells, early resolution of the inflammatory process, and clearance of fungal load from the brain. These studies show that MP is a key inflammatory mediator that induces a protective immune response againstC. neoformans infection. This information can be used to facilitate the design of a rational approach to manipulate the immune response to C. neoformans.

scholarly journals Preferential Infection of Mature Dendritic Cells by Mouse Hepatitis Virus Strain JHM

2006 ◽  
Vol 80 (5) ◽  
pp. 2506-2514 ◽  
Author(s):  
Haixia Zhou ◽  
Stanley Perlman
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Virus Strain ◽  
Hepatitis Virus ◽  
Ex Vivo ◽  
Mouse Hepatitis Virus ◽  
Demyelinating Diseases ◽  
Immature Cells

ABSTRACT Mouse hepatitis virus strain JHM (MHV-JHM) causes acute encephalitis and acute and chronic demyelinating diseases in mice. Dendritic cells (DCs) are key cells in the initiation of innate and adaptive immune responses, and infection of these cells could potentially contribute to a dysregulated immune response; consistent with this, recent results suggest that DCs are readily infected by another strain of mouse hepatitis virus, the A59 strain (MHV-A59). Herein, we show that the JHM strain also productively infected DCs. Moreover, mature DCs were at least 10 times more susceptible than immature DCs to infection with MHV-JHM. DC function was impaired after MHV-JHM infection, resulting in decreased stimulation of CD8 T cells in vitro. Preferential infection of mature DCs was not due to differential expression of the MHV-JHM receptor CEACAM-1a on mature or immature cells or to differences in apoptosis. Although we could not detect infected DCs in vivo, both CD8+ and CD11b+ splenic DCs were susceptible to infection with MHV-JHM directly ex vivo. This preferential infection of mature DCs may inhibit the development of an efficient immune response to the virus.

Functional defects of dendritic cells in patients with CD40 deficiency

Blood ◽  
2003 ◽  
Vol 102 (12) ◽  
pp. 4099-4106 ◽  
Author(s):  
Stefania Fontana ◽  
Daniele Moratto ◽  
Surinder Mangal ◽  
Maria De Francesco ◽  
William Vermi ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
Opportunistic Infections ◽  
Ex Vivo ◽  
Interferon Γ ◽  
Interleukin 12 ◽  
Cell Mediated Immunity ◽  
Ligand Interaction ◽  
Cd40 Gene ◽  
Hyper Igm

Abstract We have recently identified 2 patients with a rare autosomal recessive form of hyper IgM disease, known as HIGM3, caused by mutations in the CD40 gene. These patients had opportunistic infections observed on X-linked hyper IgM syndrome (HIGM), suggesting that the CD40-CD40 ligand interaction is important for promoting T-cell-mediated immunity. To evaluate whether innate immunity signals may substitute CD154 for inducing the maturation of dendritic cells (DCs), we analyzed monocyte-derived DCs in these patients. Monocyte-derived DCs of HIGM3 subjects on ex vivo stimulation with tumor necrosis factor-α (TNF-α) or lipopolysaccharide (LPS) combined with interferon-γ (IFN-γ) normally express all the markers of mature DCs, such as CD83 and DC-LAMP. However, cell surface levels of HLA-DR in mature DCs are reduced, as is costimulatory activity of these cells for allogeneic naive T cells. In addition, CD40-deficient DCs secrete lower amounts of interleukin-12 (IL-12) but larger quantities of IL-10 than control subjects. Finally, analysis of circulating plasmacytoid DCs demonstrates a normal percentage of this subset in CD40-deficient cells, but IFN-α secretion in response to herpes simplex virus 1 (HSV-1) infection is severely reduced in patients. These observations suggest that the severe impairment of DC maturation may contribute to the defect of T-cell-mediated immunity observed in HIGM3 patients. (Blood. 2003;102:

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