scholarly journals Pilot Study of phoP/phoQ-DeletedSalmonella enterica Serovar Typhimurium ExpressingHelicobacter pylori Urease in Adult Volunteers

2000 ◽  
Vol 68 (4) ◽  
pp. 2135-2141 ◽  
Author(s):  
Haroula Angelakopoulos ◽  
Elizabeth L. Hohmann
Keyword(s):  
Immune Responses ◽  
Mononuclear Cells ◽  
Oral Vaccine ◽  
Multicopy Plasmid ◽  
Serovar Typhimurium ◽  
Specific Factors ◽  
Adult Volunteers ◽  
Heterologous Antigens ◽  
Previous Clinical Study

ABSTRACT Attenuated Salmonella enterica serovar Typhi has been studied as an oral vaccine vector. Despite success with attenuatedS. enterica serovar Typhimurium vectors in animals, early clinical trials of S. enterica serovar Typhi expressing heterologous antigens have shown that few subjects have detectable immune responses to vectored antigens. A previous clinical study ofphoP/phoQ-deleted S. enterica serovar Typhi expressing Helicobacter pylori urease from a multicopy plasmid showed that none of eight subjects had detectable immune responses to the vectored antigen. In an attempt to further define the variables important for engendering immune responses to vectored antigens in humans, six volunteers were inoculated with 5 × 107 to 8 × 107 CFU ofphoP/phoQ-deleted S. enterica serovar Typhimurium expressing the same antigen. Two of the six volunteers had fever; none had diarrhea, bacteremia, or other serious side effects. The volunteers were more durably colonized than in previous studies ofphoP/phoQ-deleted S. enterica serovar Typhi. Five of the six volunteers seroconverted to S. entericaserovar Typhimurium antigens and had strong evidence of anti-Salmonella mucosal immune responses by enzyme-linked immunospot studies. Three of six (three of five who seroconverted toSalmonella) had immune responses in the most sensitive assay of urease-specific immunoglobulin production by blood mononuclear cells in vitro. One of these had a fourfold or greater increase in end-point immunoglobulin titer in serum versus urease. AttenuatedS. enterica serovar Typhimurium appears to be more effective than S. enterica serovar Typhi for engendering immune responses to urease. Data suggest that this may be related to a greater stability of antigen-expressing plasmid in S. enterica serovar Typhimurium and/or prolonged intestinal colonization. Specific factors unique to nontyphoidal salmonellae may also be important for stimulation of the gastrointestinal immune system.

scholarly journals Decoration of Outer Membrane Vesicles with Multiple Antigens by Using an Autotransporter Approach

2014 ◽  
Vol 80 (18) ◽  
pp. 5854-5865 ◽  
Author(s):  
Maria H. Daleke-Schermerhorn ◽  
Tristan Felix ◽  
Zora Soprova ◽  
Corinne M. ten Hagen-Jongman ◽  
David Vikström ◽  
...  
Keyword(s):  
Immune Responses ◽  
Outer Membrane ◽  
Vaccine Development ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Heterologous Proteins ◽  
Content Type ◽  
Serovar Typhimurium ◽  
Heterologous Antigens

ABSTRACTOuter membrane vesicles (OMVs) are spherical nanoparticles that naturally shed from Gram-negative bacteria. They are rich in immunostimulatory proteins and lipopolysaccharide but do not replicate, which increases their safety profile and renders them attractive vaccine vectors. By packaging foreign polypeptides in OMVs, specific immune responses can be raised toward heterologous antigens in the context of an intrinsic adjuvant. Antigens exposed at the vesicle surface have been suggested to elicit protection superior to that from antigens concealed inside OMVs, but hitherto robust methods for targeting heterologous proteins to the OMV surface have been lacking. We have exploited our previously developed hemoglobin protease (Hbp) autotransporter platform for display of heterologous polypeptides at the OMV surface. One, two, or three of theMycobacterium tuberculosisantigens ESAT6, Ag85B, and Rv2660c were targeted to the surface ofEscherichia coliOMVs upon fusion to Hbp. Furthermore, a hypervesiculating ΔtolRΔtolAderivative of attenuatedSalmonella entericaserovar Typhimurium SL3261 was generated, enabling efficient release and purification of OMVs decorated with multiple heterologous antigens, exemplified by theM. tuberculosisantigens and epitopes fromChlamydia trachomatismajor outer membrane protein (MOMP). Also, we showed that delivery ofSalmonellaOMVs displaying Ag85B to antigen-presenting cellsin vitroresults in processing and presentation of an epitope that is functionally recognized by Ag85B-specific T cell hybridomas. In conclusion, the Hbp platform mediates efficient display of (multiple) heterologous antigens, individually or combined within one molecule, at the surface of OMVs. Detection of antigen-specific immune responses upon vesicle-mediated delivery demonstrated the potential of our system for vaccine development.

scholarly journals Cytokine Profiles and Cell Proliferation Responses to Truncated ORF2 Protein in Iranian Patients Recovered from Hepatitis E Infection

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Reza Taherkhani ◽  
Fatemeh Farshadpour ◽  
Manoochehr Makvandi ◽  
Hamid Rajabi Memari ◽  
Ali Reza Samarbafzadeh ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Immune Responses ◽  
Mononuclear Cells ◽  
Hepatitis E ◽  
Control Group ◽  
Peripheral Blood Mononuclear ◽  
Orf2 Protein ◽  
Cellular Immune ◽  
Iranian Patients

Background.The aim of this study was to evaluatehepatitis E virus(HEV) specific cellular immune responses to truncated ORF2 protein in Iranian patients recovered from HEV infection. Information about HEV-specific immune responses could be useful in finding an effective way for development of HEV vaccine.Methods.A truncated form of HEV ORF2 protein containing amino acids 112-608 was used to stimulate peripheral blood mononuclear cells (PBMCs) separated from HEV-recovered and control groups. Finally, the levels of four cytokines, IFN-γELISPOT, and cell proliferative responses following stimulation with the truncated ORF2 protein were assessed in the both groups.Results.The truncated ORF2 protein was able to induce IFN-γELISPOT and cell proliferation responses and to produce significant amounts of IFN-γand IL-12 cytokines, but low amounts of IL-10 and IL-4 cytokinesin vitro. These responses were significantly higher in the recovered group compared to the control group. These results indicate the antigenic nature of the truncated ORF2 protein and production of T helper type 1 cytokines.Conclusion.The truncated ORF2 protein can effectively induce significant cellular immune responsesand can be introduced as a potential vaccine candidate. However, further studies are required to evaluate this proteinin vivo.

Sipuleucel-T (sip-T) induced lytic CD8+ T cell responses to target antigens in men with hormone-sensitive and castration-resistant prostate cancer (CRPC).

2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 162-162
Author(s):  
Emmanuel S. Antonarakis ◽  
David I. Quinn ◽  
Adam S. Kibel ◽  
Daniel Peter Petrylak ◽  
Tuyen Vu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Cd8 T Cells ◽  
Mononuclear Cells ◽  
T Cell Responses ◽  
Cell Responses ◽  
Hormone Sensitive ◽  
Ctl Activity

162 Background: Sip-T is an FDA-approved immunotherapy for patients (pts) with asymptomatic or minimally symptomatic metastatic CRPC. Sip-T is manufactured from autologous peripheral blood mononuclear cells cultured with the immunogen PA2024, a fusion antigen of prostatic acid phosphatase (PAP) conjugated to granulocyte macrophage colony-stimulating factor. After sip-T, antibody and T cell responses to PA2024 and/or PAP correlate with improved survival. To further elucidate the mechanism of sip-T–induced immune responses, we evaluated the proliferative and lytic ability of PA2024- and PAP-specific CD8+ T cells. Methods: Mononuclear blood cells were labeled with the membrane dye carboxyfluorescein succinimidyl ester (CFSE) and cultured with PA2024 or PAP. In vitro proliferative and lytic CD8+ (cytotoxic T lymphocyte [CTL]) T cell responses to these antigens were evaluated by flow cytometry. For proliferation, progressive dilution of CFSE was measured. For CTL activity, the loss of intracellular granzyme B (GzB), indicating exocytosis of this apoptosis-mediating enzyme, was assessed. Samples were from 2 sip-T clinical trials STAND (NCT01431391) and STRIDE (NCT01981122), hormone-sensitive and CRPC pts, respectively. Results: Six wk after sip-T administration, CD8+ PAP- and PA2024-specific responses were observed (n=14 pts assessed). The magnitude of PA2024-specific CD8+ proliferative responses was greater than that for PAP-specific responses. CD8+ T cells from a subset of pts who exhibited PA2024- and/or PAP-specific proliferative responses were assessed for lytic ability. After in vitro antigen stimulation, CTL activity in all evaluated samples (n=14, PA2024; n=13, PAP) was demonstrated by a significant decrease (p<0.05) in intracellular GzB relative to a no-antigen control. Conclusions: Sip-T induced CD8+ CTL proliferation against the target antigens PAP and PA2024. Moreover, antigen-specific CTL activity provides the first direct evidence that sip-T can induce tumor cell lysis. These antigen-specific CD8+ lytic abilities were observed within 6 wk following sip-T, suggesting rapidly generated immune responses. Clinical trial information: NCT01431391; NCT01981122.

scholarly journals Suppression of antibody responses in humans infected with Trypanosoma cruzi

1980 ◽  
Vol 30 (2) ◽  
pp. 496-499
Author(s):  
D S Cunningham ◽  
M Grogl ◽  
R E Kuhn
Keyword(s):  
Trypanosoma Cruzi ◽  
Antibody Response ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Antibody Activity ◽  
Blood Leukocytes ◽  
Peripheral Blood Mononuclear ◽  
Heterologous Antigens ◽  
Cruzi Infection

Peripheral blood leukocytes from patients serologically positive for Chagas' disease were examined for their ability to respond to heterologous antigens in vitro. It was found that mononuclear cells from chagasic patients had greatly reduced ability to respond to sheep erythrocytes (SRBC) as compared with peripheral blood mononuclear cells (PBMC) from control subjects. The reduction in anti-SRBC antibody activity was independent of antigen dose and was not a result of differences in antibody response kinetics. Depletion of plastic-adherent result of differences in antibody response kinetics. Depletion of plastic-adherent cells from the PBMC of patients did not affect the suppressed state of the nonadherent lymphocytes. No relationship was evident between the duration of Trypanosoma cruzi infection and the degree of humoral responsiveness.

scholarly journals Rewiring PBMC responses to prevent CHIKV infection-specific monocyte subset redistribution and cytokine responses

2020 ◽  
Author(s):  
José Alberto Aguilar-Briseño ◽  
Mariana Ruiz Silva ◽  
Jill Moser ◽  
Mindaugas Pauzuolis ◽  
Jolanda M. Smit ◽  
...  
Keyword(s):  
Immune Responses ◽  
Mononuclear Cells ◽  
Inflammatory Responses ◽  
Chronic Arthritis ◽  
Target Cells ◽  
Monocyte Subset ◽  
Chikv Infection ◽  
Peripheral Blood Mononuclear ◽  
Vitro Model

AbstractInfection with the mosquito-borne Chikungunya virus (CHIKV) causes acute or chronic arthritis in humans. Inflammatory responses mediated by monocytes, the primary target cells of CHIKV infection in the blood, are considered to play an important role in CHIKV pathogenesis. A recent study revealed that the acute phase of CHIKV infection is characterized by a monocyte-driven response, with an expansion of the intermediate monocyte (IM) subset. In this study, we adopted a previously established in vitro model of CHIKV infection in peripheral blood mononuclear cells, to elucidate the mechanism and relevance of IM expansion in CHIKV replication and associated inflammatory responses. Our data show that infectious but not replication-incompetent CHIKV increases the frequency of IM and to a lesser extent, non-classical (NM) monocytes while reducing the number of classical monocytes (CM). The increase of IM or NM frequency coincided with the activation of inflammatory response and occurred in the absence of lymphocytes implying that monocyte-derived cues are sufficient to drive this effect. Importantly, priming of monocytes with LPS prevented expansion of IM and NM but had no effect on viral replication. It did however alter CHIKV-induced cytokine signature. Taken together, our data delineate the role of IM in CHIKV infection-specific innate immune responses and provide insight for the development of therapeutic strategies that may focus on rewiring monocyte immune responses to prevent CHIKV-mediated arthralgia and arthritis.

Depletion of the CD1d-Restricted NKT Cells Suppresses In Vitro Alloreactivity: A Possible Means To Prevent aGVHD.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3069-3069
Author(s):  
S. Patterson ◽  
I. Kotsianidis ◽  
A. Almeida ◽  
M. Politou ◽  
R. David ◽  
...  
Keyword(s):  
T Cells ◽  
Immune Responses ◽  
Mononuclear Cells ◽  
Nkt Cells ◽  
Cell Depletion ◽  
Dependent Manner ◽  
Nkt Cell ◽  
Accurate Identification ◽  
Enhancing Effect

Abstract NKT cells constitute a small (&lt;0.1% of blood and marrow T cells) but potent subset of regulatory T cells. Upon engagement of their unique TCR by the glycolipid presenting, MHC-like, non-polymorphic molecule CD1d, they are activated and secrete copious amounts of TH1 and TH2 cytokines. Activated NKT have a pivotal role in modulating all aspects of the innate and adaptive immune responses mainly through their interaction with antigen presenting cells (APC). Mice deficient in NKT or CD1d have diminished TH1 responses against a variety of pathogens and tumours. Conversely, administration of the model glycolipid α-galactosylceramide (αGC) to wild type mice considerably enhances TH1 immune responses in an NKT- and CD1d-dependent manner. In this work we sought to study the in situ role of NKT in alloreactivity. For this purpose, allogeneic mixed lymphocyte reactions (MLR) were performed using 3H incorporation assays. Purified, negatively selected CD3+ cells and irradiated allogeneic peripheral blood mononuclear cells from normal individuals were used as responders and stimulators respectively. After rigorous NKT cell (as identified by staining with the anti-TCRVα24 and -Vβ11 mAbs specific to the NKT TCR α and β chains) depletion by flow sorting we compared MLR reactivity in the presence and absence of NKT. In a series of MLR that included a panel of 4 different responders and 3–5 stimulators, depletion of NKT profoundly suppressed the proliferation by 68.5%±16.9 compared to baseline (i.e., NKT-replete MLR). This suppressive effect was mirrored by a reduction (45.3%±8) of IFNγ secretion in the supernatants of the NKT-depleted MLR compared to baseline. IL-4, IL-10 and TGFβ were not detected in either NKT replete or NKT depleted MLR. When freshly flow-sorted NKT cells were placed against the allogeneic stimulators they did not proliferate indicating that the decrease in the proliferation after NKT cell depletion is due to a decrease in the proliferation of the alloreactive T cells. Taken together, these findings indicate that NKT cells positively regulate the alloresponse, a TH1-driven immune response. Consistent with this, in MLR performed in the presence of αGC (100ng/ml), proliferation was significantly enhanced as compared to baseline MLR (i.e., performed in the presence of the αGC diluent). In a panel of 5 responders against a panel of 3–5 stimulators treatment of the MLR with αGC resulted in a 43.2%±15.2 increase in proliferation. In accordance with the proliferation data, IGNγ production was significantly increased (mean of 53%), whereas IL-4 was undetectable under both conditions. Furthermore, the enhancing effect of αGC was NKT-dependent, as in NKT-depleted MLR proliferation was equally suppressed in the presence of αGC and its diluent (82.6±6.8 vs 82±8.5 respectively, n=3).In summary, we have demonstrated that NKT cells exert an enhancing effect on the alloreactive response and NKT cell depletion effectively suppresses in vitro alloreactivity. These findings set the scene for exploring on one hand the potential for reducing the risk of severe aGVHD by using NKT depletion in allogeneic haemopoietic stem cell transplantation and on the other hand for exploring the adoptive transfer of purified NKT cells to improve immune reconstitution post transplant. In either case, the rapid, accurate identification and physical isolation of the NKT cells is possible either with the use of mAbs highly specific for the TCR of the NKT cells or with the use of the CD1d/α GC tetramer.

Disease activity and the immune set in multiple sclerosis: blood markers for immunotherapy

1998 ◽  
Vol 4 (3) ◽  
pp. 232-238 ◽  
Author(s):  
A J Coles ◽  
M G Wing ◽  
D AS Compston
Keyword(s):  
Multiple Sclerosis ◽  
T Cell ◽  
Immune Responses ◽  
Mononuclear Cells ◽  
Myelin Proteins ◽  
Peripheral Blood Mononuclear ◽  
Passive Measurement ◽  
Immunological Surveillance ◽  
Experimental Treatments

There is no established immunological marker of multiple sclerosis activity, which reflects the poor understanding of the immunopathogenesis of multiple sclerosis. Passive measurement of the levels of soluble inflammatory markers, whose half lives are usually measured in minutes and hours, can only indicate the extent of instantaneous inflammation, which is known to fluctuate in multiple sclerosis. We favour measurement of immune responses in vitro. As healthy individuals have T cell reactivities to myelin proteins that are postulated to be pathogenic in multiple sclerosis,1,2we prefer non-antigen specific mitogen and recall antigen assays as immunological markers. We illustrate their use in the treatment of 27 patients with multiple sclerosis using a pulse of humanised anti-lymphocyte (CD52) antibody that caused prolonged T cell depletion. The mitogen-induced proliferation, and secretion of IFN-g, from peripheral blood mononuclear cells in vitro was significantly reduced after treatment, suggesting that immune responses had been modulated. Such observations will only gain credence as an outcome measure if they are shown to correlate with clinical or radiological measures of multiple sclerosis activity. Perhaps more importantly, aspects of the pathogenesis of multiple sclerosis may be revealed by close immunological surveillance of patients undergoing experimental treatments.

scholarly journals Effect of Preexisting Immunity to Salmonella on the Immune Response to Recombinant Salmonella enterica Serovar Typhimurium Expressing a Porphyromonas gingivalisHemagglutinin

2000 ◽  
Vol 68 (6) ◽  
pp. 3116-3120 ◽  
Author(s):  
James J. Kohler ◽  
Latha B. Pathangey ◽  
Sheila R. Gillespie ◽  
Thomas A. Brown
Keyword(s):  
Immune Responses ◽  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Oral Vaccine ◽  
Oral Immunization ◽  
Primary Response ◽  
Serum Iga ◽  
Serovar Typhimurium ◽  
Live Oral Vaccine ◽  
Carrier Strain

ABSTRACT Recombinant Salmonella strains expressing foreign heterologous genes have been extensively studied as live oral vaccine delivery vectors. We have investigated the mucosal and systemic immune responses following oral immunization with a recombinantSalmonella enterica serovar Typhimurium expressing the hemagglutinin HagB from Porphyromonas gingivalis, a suspected etiological agent of adult periodontal disease. We have previously shown a primary mucosal and systemic response following oral immunization with χ4072/pDMD1 and recall responses following boosting at 14 weeks after primary immunization. In this study, we examined the effects of earlier boosting as well as the effects of deliberately induced immunity to the Salmonella carrier strain on subsequent immune responses. Mice boosted at week 7 following immunization, a point which corresponded to the peak of the primary response, generally showed lower responses than those boosted at week 14. When mice were preimmunized with the Salmonella carrier alone and then immunized with the recombinant strain 7 or 14 weeks later, significant reductions were seen for serum immunoglobulin G (IgG) antibodies at week 14 and for salivary IgA at week 7. No reductions were seen in serum IgA or vaginal wash IgA antibodies. Mice appear to be refractory to boosting with orally administered salmonellae at 7 weeks. Deliberate immunization with the carrier strain did not appreciably affect recall responses at 14 weeks, with the exception of the serum IgG responses, nor did it affect colonization of the Peyer's patches.

Analysis of T-helper Responses and FOXP3 Gene Expression in Patients with Japanese Cedar Pollinosis

2008 ◽  
Vol 22 (6) ◽  
pp. 582-588 ◽  
Author(s):  
Kazuaki Chikamatsu ◽  
Koichi Sakakura ◽  
Tomokazu Matsuoka ◽  
Shuichiro Endo ◽  
Goro Takahashi ◽  
...  
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Immune Responses ◽  
Mononuclear Cells ◽  
Japanese Cedar ◽  
T Helper ◽  
Foxp3 Gene ◽  
Healthy Donors ◽  
Japanese Cedar Pollinosis

Background Evidence has been accumulated indicating that regulatory T (T-reg) cells play a crucial role in the maintenance of peripheral T-cell tolerance to allergens. To explore the role of FOXP3, which is required for the development of T-reg cells, in allergen-specific immune responses, we examined the relationship between the alteration of FOXP3 gene expression and in vitro immune responses against allergens. Methods Peripheral blood mononuclear cells obtained from 19 human histocompatibility leukocyte antigens (HLA)-DPB1*0501 donors, including patients with Japanese cedar pollinosis and nonallergic healthy donors, were stimulated with Cry j 1 p61-75 peptide. On day 7, T cells were tested for peptide-specific reactivity in IFN-γ and interleukin (IL)-5 enzyme-linked immunospot (ELISPOT) assays. Real-time quantitative RT-PCR was performed to assess relative change of FOXP3 gene expression before and after in vitro stimulation. Neutralization assays using anti-glucocorticoid-induced tumor necrosis factor receptor family-related protein (GITR) and anti-IL-10 monoclonal antibody were also performed. Results Of 14 patients with allergic pollinosis tested, 10 responders displayed T-helper type 2 (Th2)-polarized reactivity to Cry j 1 p61-75, and 2 donors showed Th0 responses. Notably, the change of FOXP3 gene expression in donors showing peptide-specific T-helper responses was significantly lower than that in nonresponders, regardless of allergic pollinosis. Conclusion Our data indicate that FOXP3 is functional in nonallergic healthy donors as well as allergic patients, and FOXP3-expressing T cells may be responsible for the down-regulation of allergen-specific T-helper responses in individuals. A better understanding of the nature and specificity of FOXP3-expressing T cells in a suppressive mechanism is necessary to develop new immunotherapies against allergic rhinitis.

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