scholarly journals TGFβ2 Induces the Soluble Isoform of CTLA-4 – Implications for CTLA-4 Based Checkpoint Inhibitor Antibodies in Malignant Melanoma

2022 ◽  
Vol 12 ◽  
Author(s):  
Rahul C. Khanolkar ◽  
Chu Zhang ◽  
Farah Al-Fatyan ◽  
Linda Lawson ◽  
Ivan Depasquale ◽  
...  
Keyword(s):  
Malignant Melanoma ◽  
Immune Responses ◽  
Immune Evasion ◽  
Melanoma Patient ◽  
Checkpoint Inhibitor ◽  
Serum Levels ◽  
Contributory Factor ◽  
Cytokine Responses ◽  
Aggressive Form

Malignant melanoma is an aggressive form of cancer, which can be treated with anti-CTLA-4 and anti-PD-1 checkpoint inhibitor antibodies but while anti-CTLA-4 antibodies have clear benefits for some patients with melanoma, productive responses are difficult to predict and often associated with serious immune related adverse events. Antibodies specific to CTLA-4 bind two major isoforms of CTLA-4 in humans, the receptor isoform and a second naturally secretable, soluble isoform - sCTLA-4. The primary aim here was to examine the effect of selectively blocking the function of sCTLA-4 on in vitro immune responses from volunteer healthy or melanoma patient PBMC samples. Addition of recombinant sCTLA-4 to healthy PBMC samples demonstrated sCTLA-4 to have immunosuppressive capacity comparable to recombinant CTLA4-Ig, partially reversible upon antibody blockade. Further, we identified a mechanistic relationship where melanoma patient TGFβ2 serum levels correlated with sCTLA-4 levels and provided the basis for a novel protocol to enhance sCTLA-4 production and secretion by T cells with TGFβ2. Finally, a comparison of selective antibody blockade of sCTLA-4 demonstrated that both healthy and melanoma patient effector cytokine responses can be significantly increased. Overall, the data support the notion that sCTLA-4 is a contributory factor in cancer immune evasion.

Thermoregulatory responses of rats to conventional preparations of lipopolysaccharide are caused by lipopolysaccharide per se— not by lipoprotein contaminants

2005 ◽  
Vol 289 (2) ◽  
pp. R348-R352 ◽  
Author(s):  
Alexandre A. Steiner ◽  
Sumana Chakravarty ◽  
Jared R. Robbins ◽  
Alexander S. Dragic ◽  
Jennifer Pan ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Serum Levels ◽  
Toll Like Receptor ◽  
Tlr4 Signaling ◽  
Highly Active ◽  
Cytokine Responses ◽  
Tnf Α ◽  
Per Se ◽  
Phenol Water

LPS preparations cause a variety of body temperature (Tb) responses: monophasic fever, different phases of polyphasic fever, and hypothermia. Conventional (c) LPS preparations contain highly active lipoprotein contaminants (endotoxin proteins). Whereas LPS signals predominantly via the Toll-like receptor (TLR) 4, endotoxin proteins signal via TLR2. Several TLR2-dependent responses of immunocytes to cLPS in vitro are triggered by endotoxin proteins and not by LPS itself. We tested whether any Tb response to cLPS from Escherichia coli 055:B5 is triggered by non-TLR4-signaling contaminants. A decontaminated (d) LPS preparation (free of endotoxin proteins) was produced by subjecting cLPS to phenol-water reextraction. The presence of non-TLR4-signaling contaminants in cLPS (and their absence in dLPS) was confirmed by showing that cLPS (but not dLPS) induced IL-1β expression in the spleen and increased serum levels of TNF-α and IL-1β of C3H/HeJ mice; these mice bear a nonfunctional TLR4. Yet, both cLPS and dLPS caused cytokine responses in C3H/HeOuJ mice; these mice bear a fully functional TLR4. We then studied the Tb responses to cLPS and dLPS in Wistar rats preimplanted with jugular catheters. At a neutral ambient temperature (30°C), a low (0.1 μg/kg iv) dose of cLPS caused a monophasic fever, whereas a moderate (10 μg/kg iv) dose produced a polyphasic fever. In the cold (20°C), a high (500 μg/kg iv) dose of cLPS caused hypothermia. All Tb responses to dLPS were identical to those of cLPS. We conclude that all known Tb responses to LPS preparations are triggered by LPS per se and not by non-TLR4-signaling contaminants of such preparations.

scholarly journals Dysbiosis and zonulin upregulation alter gut epithelial and vascular barriers in patients with ankylosing spondylitis

2017 ◽  
Vol 76 (6) ◽  
pp. 1123-1132 ◽  
Author(s):  
Francesco Ciccia ◽  
Giuliana Guggino ◽  
Aroldo Rizzo ◽  
Riccardo Alessandro ◽  
Michele Maria Luchetti ◽  
...  
Keyword(s):  
Ankylosing Spondylitis ◽  
Immune Responses ◽  
Tight Junctions ◽  
Ex Vivo ◽  
Serum Levels ◽  
Mucosal Barrier ◽  
Blood Levels ◽  
Hla B27 ◽  
Bacterial Products

BackgroundDysbiosis has been recently demonstrated in patients with ankylosing spondylitis (AS) but its implications in the modulation of intestinal immune responses have never been studied. The aim of this study was to investigate the role of ileal bacteria in modulating local and systemic immune responses in AS.MethodsIleal biopsies were obtained from 50 HLA-B27+ patients with AS and 20 normal subjects. Silver stain was used to visualise bacteria. Ileal expression of tight and adherens junction proteins was investigated by TaqMan real-time (RT)-PCR and immunohistochemistry. Serum levels of lipopolysaccharide (LPS), LPS-binding protein (LPS-BP), intestinal fatty acid-BP (iFABP) and zonulin were assayed by ELISA. Monocyte immunological functions were studied in in vitro experiments. In addition the effects of antibiotics on tight junctions in human leukocyte antigen (HLA)-B27 transgenic (TG) rats were assessed.ResultsAdherent and invasive bacteria were observed in the gut of patients with AS with the bacterial scores significantly correlated with gut inflammation. Impairment of the gut vascular barrier (GVB) was also present in AS, accompanied by significant upregulation of zonulin, and associated with high serum levels of LPS, LPS-BP, iFABP and zonulin. In in vitro studies zonulin altered endothelial tight junctions while its epithelial release was modulated by isolated AS ileal bacteria. AS circulating monocytes displayed an anergic phenotype partially restored by ex vivo stimulation with LPS+sCD14 and their stimulation with recombinant zonulin induced a clear M2 phenotype. Antibiotics restored tight junction function in HLA-B27 TG rats.ConclusionsBacterial ileitis, increased zonulin expression and damaged intestinal mucosal barrier and GVB, characterises the gut of patients with AS and are associated with increased blood levels of zonulin, and bacterial products. Bacterial products and zonulin influence monocyte behaviour.

scholarly journals Vaccination with Adenovirus Serotypes 35, 26, and 48 Elicits Higher Levels of Innate Cytokine Responses than Adenovirus Serotype 5 in Rhesus Monkeys

2012 ◽  
Vol 86 (18) ◽  
pp. 9590-9598 ◽  
Author(s):  
Jeffrey E. Teigler ◽  
M. Justin Iampietro ◽  
Dan H. Barouch
Keyword(s):  
Immune Responses ◽  
Rhesus Monkeys ◽  
Interleukin 1 ◽  
Experimental Models ◽  
Gamma Interferon ◽  
Vaccine Vectors ◽  
Adenovirus Serotype ◽  
Cytokine Responses ◽  
Serotype 5

Adenovirus (Ad) vaccine vectors have proven highly immunogenic in multiple experimental models, but the innate immune responses induced by these vectors remain poorly characterized. Here we report innate cytokine responses to 5 different Ad vectors in 26 rhesus monkeys. Vaccination with adenovirus serotype 35 (Ad35), Ad26, and Ad48 induced substantially higher levels of antiviral (gamma interferon [IFN-γ], 10-kDa gamma interferon-induced protein [IP-10]) and proinflammatory (interleukin 1 receptor antagonist [IL-1RA], IL-6) cytokines than vaccination with Ad5 on day 1 following immunization.In vitrostudies with capsid chimeric vectors and receptor-blocking monoclonal antibodies suggested that fiber-receptor interactions, as well as other capsid components, were critical for triggering these innate responses. Moreover, multiple cell populations, including dendritic cells, monocytes/macrophages, and T lymphocytes, contributed to these innate cytokine profiles. These data demonstrate that Ad35, Ad26, and Ad48, which utilize CD46 as their primary cellular receptor, induce significantly greater innate cytokine responses than Ad5, which uses the coxsackievirus and adenovirus receptor (CAR). These differences in innate triggering result in markedly different immunologic milieus for the subsequent generation of adaptive immune responses by these vaccine vectors.

scholarly journals Helminth infection is associated with dampened cytokine responses to viral and bacterial stimulations in Tsimane hunter-horticulturalists

2021 ◽  
Author(s):  
India Schneider-Crease ◽  
Aaron D. Blackwell ◽  
Thomas S. Kraft ◽  
Melissa Emery Thompson ◽  
Ivan Maldonado Suarez ◽  
...  
Keyword(s):  
Immune Responses ◽  
Inflammatory Responses ◽  
Remote Communities ◽  
Necrosis Factor Alpha ◽  
H1n1 Vaccine ◽  
Gm Csf ◽  
Th2 Cytokine ◽  
Cytokine Responses ◽  
Macrophage Colony

AbstractBackgroundSoil-transmitted helminth (STH) infections can catalyze immunological changes that affect the response to subsequent infections, particularly those that elicit strong inflammatory responses. As globalization heightens the risk that remote communities with high STH prevalence will encounter novel pathogens, understanding how STHs shape immune responses to these downstream infections becomes increasingly crucial.MethodologyWe worked with Tsimane forager-horticulturalists in the Bolivian Amazon, where STHs are prevalent. We tested whether STHs and eosinophil levels—most likely indicative of infection in this population—are associated with dampened immune responses to in vitro stimulation with H1N1 and lipopolysaccharide (LPS) antigens. Whole blood samples (n = 179) were treated with H1N1 vaccine and LPS and assayed for 13 cytokines (interferon gamma [INF-γ], interleukin [IL]-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12p70, IL-13, Granulocyte-macrophage colony-stimulating factor [GM-CSF], and Tumor necrosis factor-alpha [TNF-α]). We evaluated how STHs and eosinophil levels affected cytokine responses and T helper (Th) 1 and Th2-cytokine suite responses to stimulation.ResultsInfection with Ascaris lumbricoides was significantly (p ≤ 0.05) associated with lower response of some cytokines to H1N1 and LPS in women. Eosinophils were significantly negatively associated with some cytokine responses to H1N1 and LPS, with the strongest effects in women, and associated with a reduced Th1- and Th2-cytokine response to H1N1 and LPS in women and men.Conclusions and implicationsWe find that STHs were associated with dampened cytokine responses to certain viral and bacterial antigens, and suggest that this mitigation of host-induced damage may reduce the incidence of cytokine storms in populations with high STH prevalence.

MicroRNA-155 Expression With Brucella Infection in vitro and in vivo and Decreased Serum Levels of MicroRNA-155 in Patients With Brucellosis

2021 ◽  
Author(s):  
Xi Zhang ◽  
Jingjing Chen ◽  
Huimin Cheng ◽  
Jinying Zhu ◽  
Qiao Dong ◽  
...  
Keyword(s):  
Immune Responses ◽  
Early Stage ◽  
Serum Levels ◽  
Human Brucellosis ◽  
Host Immune Responses ◽  
Contrasting Effect ◽  
Antibody Titers ◽  
Unique Mechanism

Abstract Infection by Brucella is characterized by the inhibition of host immune responses. MicroRNA-155 (miR-155) has been implicated in the immune response to many diseases. In this study, miR-155 expression during Brucella 16M infection of macrophages and mice were analyzed. Expression of miR-155 was significantly induced in macrophages at 24 hours post infection. Analysis of infected mice showed that miR-155 was inhibited at 7 and 14 days, but induced at 28 days. Very interestingly, the induction or inhibition trend was reversed at 7 and 14 days in 16M△virB-infected mice. This suggested that decreased expression of miR-155 at an early stage of infection was dependent on intracellular replication. In humans with brucellosis, serum levels of miR-155 were significantly decreased compared to those without brucellosis and healthy volunteers. Significant correlations were observed between serum level of miR-155 and serum anti-Brucella antibody titers and symptom of sweat. The decrease in miR-155 with Brucella infection contrasts with the increase in miR-155 observed in Mycobacterium tuberculosis infection. This contrasting effect suggests that Brucella interferes with miR-155-regulated immune responses through a unique mechanism. Taken together, data from this study indicate that Brucella infection affects miR-155 expression, and that human brucellosis patients show decreased serum levels of miR-155.

scholarly journals Targeting LAG3/GAL-3 to overcome immunosuppression and enhance anti-tumor immune responses in multiple myeloma

Leukemia ◽  
2021 ◽  
Author(s):  
Jooeun Bae ◽  
Fabrizio Accardi ◽  
Teru Hideshima ◽  
Yu-Tzu Tai ◽  
Rao Prabhala ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
T Cells ◽  
Immune Responses ◽  
Checkpoint Inhibitor ◽  
Immune Checkpoints ◽  
Specific Memory ◽  
Immune Profiling ◽  
Improve Patient ◽  
Inhibitor Treatment

AbstractImmune profiling in patients with monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), and multiple myeloma (MM) provides the framework for developing novel immunotherapeutic strategies. Here, we demonstrate decreased CD4+ Th cells, increased Treg and G-type MDSC, and upregulation of immune checkpoints on effector/regulatory and CD138+ cells in MM patients, compared MGUS/SMM patients or healthy individuals. Among the checkpoints profiled, LAG3 was most highly expressed on proliferating CD4+ Th and CD8+ Tc cells in MM patients BMMC and PBMC. Treatment with antibody targeting LAG3 significantly enhanced T cells proliferation and activities against MM. XBP1/CD138/CS1-specific CTL generated in vitro displayed anti-MM activity, which was further enhanced following anti-LAG3 treatment, within the antigen-specific memory T cells. Treg and G-type MDSC weakly express LAG3 and were minimally impacted by anti-LAG3. CD138+ MM cells express GAL-3, a ligand for LAG3, and anti-GAL-3 treatment increased MM-specific responses, as observed for anti-LAG3. Finally, we demonstrate checkpoint inhibitor treatment evokes non-targeted checkpoints as a cause of resistance and propose combination therapeutic strategies to overcome this resistance. These studies identify and validate blockade of LAG3/GAL-3, alone or in combination with immune strategies including XBP1/CD138/CS1 multipeptide vaccination, to enhance anti-tumor responses and improve patient outcome in MM.

scholarly journals 460 The immuno-metabolic enzyme FASN prevents anti-tumor immune responses in irradiated glioblastoma

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A488-A488
Author(s):  
Mara De Martino ◽  
Camille Daviaud ◽  
Claire Vanpouille-Box
Keyword(s):  
T Cells ◽  
Immune Responses ◽  
Immune Evasion ◽  
Cd8 T Cells ◽  
Fatty Acid Synthase ◽  
De Novo ◽  
Metabolic Reprogramming ◽  
Metabolic Enzyme ◽  
Strong Increase

BackgroundImmunotherapy (IT) has evolved as an essential pillar against cancer due to unprecedented successes in several malignancies. However, only 10% of glioblastoma (GBM) patients respond to IT, presumably due to the paucity of tumor-infiltrating lymphocytes. Radiotherapy (RT) can promote T cells infiltration to generate anti-tumor immune responses, but can also exacerbate potent immune inhibitory mechanism to facilitate immune evasion. Among which, metabolic reprogramming of irradiated GBM represents an emerging mechanism of immune resistance. Notably, increased lipogenesis by the fatty acid synthase (FASN) is a hallmark of GBM that was shown to mediate radioresistance and immunosuppression in other cancer types. Therefore, we hypothesize that de novo lipid biosynthesis mediated by FASN represents an innate immune evasion mechanism in irradiated GBM.MethodsWe first defined metabolic changes 24hrs after RT (10 gray - Gy) by seahorse assay and metabolomics in the syngeneic murine GBM model, GL261. To confirm alterations in the lipogenesis pathway, we measured the expression FASN by western blot and the cell lipid content by BODIPY staining and flow cytometry. Finally, GL261 cells were engineered to express an inducible shRNA silencing FASN (GL261shFASN) or its non-silencing control (GL261shNS) and orthotopically implanted on day 0. On day 6, knockdown of FASN was induced by feeding the mice with doxycycline. On day 11, mice received 10Gy irradiation selectively to the tumor. Evaluation of the immune contexture was determined by in situ immunofluorescence on day 19 (n=3/group). Remaining mice were followed for survival (n=7/group).ResultsMitochondrial respiration and glycolysis were significantly enhanced in RT-GL261 cells in vitro. Metabolomic profiling of RT-GL261 cells showed a strong increase in pathways related to nucleotide, amino acids and lipid metabolism. Consistent with this last observation, we found upregulation of FASN and lipids accumulation in RT-GL261 cells as compared to non-RT GL261 cells. In vivo, GL261shFASN tumors presented increased infiltration of CD11c+ and CD8+ T cells as compared to GL261shNS tumors; an observation that was amplified in RT-GL261shFASN tumors. Consistent with a recruitment of CD11c+ and CD8+ T cells, 43% of mice bearing GL261shFASN tumor survived for at least 60 days without tumor regrowth vs. 35 days in GL261shNS tumor bearing mice.ConclusionsAltogether our data suggest that RT is inducing a metabolic reprogramming of GBM by promoting FASN-mediated lipid synthesis to foster immunosuppression. While much work remains to be done, our data propose FASN as a novel therapeutic target to overcome immunosuppression and sensitize irradiated GBM to ITs.Ethics ApprovalAll mice experiments were approved by the Institutional Animal Care and Use Committee, protocol number 2019-0042.

scholarly journals Zika Virus Envelope Domain III Recombinant Protein Delivered With Saponin-Based Nanoadjuvant From Quillaja brasiliensis Enhances Anti-Zika Immune Responses, Including Neutralizing Antibodies and Splenocyte Proliferation

2021 ◽  
Vol 12 ◽  
Author(s):  
Samuel Cibulski ◽  
Ana Paula Muterle Varela ◽  
Thais Fumaco Teixeira ◽  
Martín Pablo Cancela ◽  
Patrícia Sesterheim ◽  
...  
Keyword(s):  
Recombinant Protein ◽  
Immune Responses ◽  
Zika Virus ◽  
Neutralizing Antibodies ◽  
Serum Levels ◽  
Delivery Systems ◽  
Virus Envelope ◽  
Great Ability ◽  
Domain Iii

Nanoadjuvants that combine immunostimulatory properties and delivery systems reportedly bestow major improvements on the efficacy of recombinant, protein-based vaccines. Among these, self-assembled micellar formulations named ISCOMs (immune stimulating complexes) show a great ability to trigger powerful immunological responses against infectious pathogens. Here, a nanoadjuvant preparation, based on saponins from Quillaja brasiliensis, was evaluated together with an experimental Zika virus (ZIKV) vaccine (IQB80-zEDIII) and compared to an equivalent vaccine with alum as the standard adjuvant. The preparations were administered to mice in two doses (on days zero and 14) and immune responses were evaluated on day 28 post-priming. Serum levels of anti-Zika virus IgG, IgG1, IgG2b, IgG2c, IgG3 were significantly increased by the nanoadjuvant vaccine, compared to the mice that received the alum-adjuvanted vaccine or the unadjuvanted vaccine. In addition, a robust production of neutralizing antibodies and in vitro splenocyte proliferative responses were observed in mice immunized with IQB80-zEDIII nanoformulated vaccine. Therefore, the IQB80-zEDIII recombinant preparation seems to be a suitable candidate vaccine for ZIKV. Overall, this study identified saponin-based delivery systems as an adequate adjuvant for recombinant ZIKV vaccines and has important implications for recombinant protein-based vaccine formulations against other flaviviruses and possibly enveloped viruses.

scholarly journals RIG-I Signaling via MAVS Is Dispensable for Survival in Lethal Influenza Infection In Vivo

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Wenxin Wu ◽  
Xiaoqiu Wang ◽  
Wei Zhang ◽  
Lili Tian ◽  
J. Leland Booth ◽  
...  
Keyword(s):  
Immune Responses ◽  
Influenza A ◽  
Influenza Infection ◽  
Lavage Fluid ◽  
Innate Immune ◽  
Innate Immune Responses ◽  
Downstream Signaling ◽  
Cytokine Responses

Retinoic acid-inducible gene I (RIG-I) is an important regulator of virus-induced antiviral interferons (IFNs) and proinflammatory cytokines. It requires interaction with an adaptor molecule, mitochondrial antiviral-signaling protein (MAVS), to activate downstream signaling pathways. To elucidate the mechanism(s) by which RIG-I-dependent recognition of IAV infection in vivo triggers innate immune responses, we infected mutant mice lacking RIG-I or MAVS with influenza A virus (IAV) and measured their innate immune responses. As has previously been demonstrated with isolated deletion of the virus recognition receptors TLR3, TLR7, and NOD2, RIG-I or MAVS knockout (KO) did not result in higher mortality and did not reduce IAV-induced cytokine responses in mice. Infected RIG-I KO animals displayed similar lung inflammation profiles as did WT mice, in terms of the protein concentration, total cell count, and inflammatory cell composition in the bronchoalveolar lavage fluid. RNA-Seq results demonstrated that all types of mice exhibited equivalent antiviral and inflammatory gene responses following IAV infection. Together, the results indicated that although RIG-I is important in innate cytokine responses in vitro, individual deletion of the genes encoding RIG-I or MAVS did not change survival or innate responses in vivo after IAV infection in mice.

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