scholarly journals Downregulation of Th1 cytokine production accompanies induction of Th2 responses by a parasitic helminth, Schistosoma mansoni.

1991 ◽  
Vol 173 (1) ◽  
pp. 159-166 ◽  
Author(s):  
E J Pearce ◽  
P Caspar ◽  
J M Grzych ◽  
F A Lewis ◽  
A Sher
Keyword(s):  
T Cells ◽  
Schistosoma Mansoni ◽  
Cytokine Production ◽  
Specific Antigen ◽  
Th2 Cytokines ◽  
Th2 Response ◽  
Ifn Gamma ◽  
Larval Stages ◽  
Th2 Responses ◽  
Th1 Cytokine

In the mouse, infection with Schistosoma mansoni results in an egg-producing infection and associated disease, whereas vaccination with attenuated larval stages produces a substantial and specific immunity in the absence of egg-induced pathology. Preliminary data showing enhanced interleukin-5 (IL-5) production by T cells from infected mice and interferon gamma (IFN-gamma) synthesis by cells from vaccinated animals (7), suggested differential CD4+ subset stimulation by the different parasite stimuli. To confirm this hypothesis, lymphocytes from vaccinated or infected animals were compared for their ability to produce IFN-gamma and IL-2 (secreted by Th1 cells) as compared with IL-4 and IL-5 (characteristic Th2 cytokines). After stimulation with specific antigen or mitogen, T cells from vaccinated mice or prepatently infected animals responded primarily with Th1 lymphokines, whereas lymphocytes from patently infected mice instead produced Th2 cytokines. The Th2 response in infected animals was shown to be induced by schistosome eggs and directed largely against egg antigens, whereas the Th1 reactivity in vaccinated mice was triggered primarily by larval antigens. Interestingly, Th1 responses in mice carrying egg-producing infections were found to be profoundly downregulated. Moreover, the injection of eggs into vaccinated mice resulted in a reduction of antigen and mitogen-stimulated Th1 function accompanied by a coincident expression of Th2 responses. Together, the data suggest that coincident with the induction of Th2 responses, murine schistosome infection results in an inhibition of potentially protective Th1 function. This previously unrecognized downregulation of Th1 cytokine production may be an important immunological consequence of helminth infection related to host adaptation.

Decreased Expression and Function of Vß6+ and Vß14+ T Cells is Associated with Decreased Th1 Cytokine Production in Mice with Plasma Cell Tumors

1996 ◽  
Vol 82 (1) ◽  
pp. 22-26 ◽  
Author(s):  
Heather E. Stefanski ◽  
Ambika Mathur
Keyword(s):  
T Cells ◽  
Plasma Cell ◽  
Cd8 T Cells ◽  
Cytokine Production ◽  
Cell Tumor ◽  
Cell Surface Expression ◽  
Ifn Gamma ◽  
Plasma Cell Tumor ◽  
Th1 Cytokine ◽  
And Function

Aims and background We have found that polyclonally stimulated T cells from mice bearing ascitic plasma cell tumors demonstrate specific decreases in Th1 cytokine production. In this study we investigated whether loss of Th1 responses in the plasma cell tumor system was associated with alterations in the Vß T cell receptor repertoire. Methods We examined the cell surface expression of specific Vß expressing splenic CD4+ or CD8+ T cells from normal and tumor bearing mice using direct three-color flowcytometry. In order to determine the Th phenotype of Vß expressing T cells, we enriched for Vß6, Vß14 or Vß8.1,8.2 cells, polyclonally stimulated them and measured the levels of the cytokines interleukin-4 (IL-4), IL-2 and interferon-gamma (IFN-gamma). Results We find that there is a statistically significant decrease in the frequency of Vß6+ and Vß14+ CD8+ T cells in mice bearing a plasma cell tumor (B53) as compared to normals (p<0.05). Stimulated Vß6+ and Vß14+ T cells exhibit an exclusively Th1 phenotype. Stimulated Vß6+ and Vß14+ T cells from B53 mice are deficient in production of the Th1 cytokines. In contrast, stimulated Vß8.1,8.2+ T cells, which are not altered in B53 mice, reveal a Th2 phenotype. Conclusions The significance of this study is our demonstration that decreased expression and function of Vß6+ and Vß14+ T cells may be, at least in part, responsible for the decrease in the production of IL-2 and/or IFN-gamma observed in hosts with tumors.

The impact of a multi-epitope melanoma helper peptide vaccine on Th1 cytokine production by responding lymphocytes.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e19028-e19028
Author(s):  
Patrick Michael Dillon ◽  
Walter C. Olson ◽  
Kimberly A. Chianese-Bullock ◽  
Andrea Czarkowski ◽  
Craig L. Slingluff
Keyword(s):  
T Cells ◽  
Cytokine Production ◽  
Cytokine Profile ◽  
Helper T Cells ◽  
Th2 Cytokines ◽  
Measurable Disease ◽  
Th1 And Th2 Cytokines ◽  
Th1 Cytokine ◽  
The Impact ◽  
Th1 And Th2

e19028 Background: Melanomas produce soluble and cell-associated molecules that can suppress or alter antitumor immunity. Preclinical studies suggest the disease burden may alter the cytokine profile of helper T cell responses to cancer antigens. To describe the vaccine-induced production of Th2 or Th1 responses to helper peptides in the setting of advanced melanoma, we measured cytokine production of helper T cells responding to vaccination by 6 melanoma helper peptides (6MHP). We then analyzed results by measurable disease status. Methods: Thirty-nine patients with stage IIIB-IV melanoma received a 6MHP vaccine as a part of the UVA Mel41 clinical trial. For analysis of this correlative endpoint, antigen-reactive T cells were exposed to antigen, and supernatants (days 2 and 5) were assayed by cytokine bead arrays for Th1 and Th2 cytokines. Results: The dominant Th1 and Th2 cytokines detected were IFN-g and IL-5, respectively, though high levels of IL-2 were also produced early by sentinel lymph node lymphocytes. Th1 cytokine responses predominated both pre and post vaccine. Peripheral blood lymphocytes from patients with clinically measurable disease produced similar levels of total cytokine as patients with no evidence of disease (111pg/ml versus 174pg/ml respectively, p=0.44). For both disease statuses, the cytokine profile was Th1-dominant in most patients. Total cytokine production varied significantly among patients and varied over time but persisted up to nine months post-vaccine. Conclusions: The MHC class II-associated peptides used in this study induced helper T cells with a Th1-biased cytokine response in both PBMC and sentinel immunized nodes. However, both groups of patients can mount a Th1 dominant response to these peptides, which may persist long after the vaccination sequence. Future studies are needed to test newer vaccine adjuvants in combination with these peptides.

CCR5 deficiency decreases susceptibility to experimental cerebral malaria

Blood ◽  
2003 ◽  
Vol 101 (11) ◽  
pp. 4253-4259 ◽  
Author(s):  
Elodie Belnoue ◽  
Michèle Kayibanda ◽  
Jean-Christophe Deschemin ◽  
Mireille Viguier ◽  
Matthias Mack ◽  
...  
Keyword(s):  
T Cells ◽  
Cerebral Malaria ◽  
Cd8 T Cells ◽  
Cytokine Production ◽  
Wild Type ◽  
Experimental Cerebral Malaria ◽  
Pathologic Features ◽  
Th1 Cytokine ◽  
The Brain ◽  
Deficient Mice

Abstract Infection of susceptible mouse strains with Plasmodium berghei ANKA (PbA) is a valuable experimental model of cerebral malaria (CM). Two major pathologic features of CM are the intravascular sequestration of infected erythrocytes and leukocytes inside brain microvessels. We have recently shown that only the CD8+ T-cell subset of these brain-sequestered leukocytes is critical for progression to CM. Chemokine receptor–5 (CCR5) is an important regulator of leukocyte trafficking in the brain in response to fungal and viral infection. Therefore, we investigated whether CCR5 plays a role in the pathogenesis of experimental CM. Approximately 70% to 85% of wild-type and CCR5+/- mice infected with PbA developed CM, whereas only about 20% of PbA-infected CCR5-deficient mice exhibited the characteristic neurologic signs of CM. The brains of wild-type mice with CM showed significant increases in CCR5+ leukocytes, particularly CCR5+ CD8+ T cells, as well as increases in T-helper 1 (Th1) cytokine production. The few PbA-infected CCR5-deficient mice that developed CM exhibited a similar increase in CD8+ T cells. Significant leukocyte accumulation in the brain and Th1 cytokine production did not occur in PbA-infected CCR5-deficient mice that did not develop CM. Moreover, experiments using bone marrow (BM)–chimeric mice showed that a reduced but significant proportion of deficient mice grafted with CCR5+ BM develop CM, indicating that CCR5 expression on a radiation-resistant brain cell population is necessary for CM to occur. Taken together, these results suggest that CCR5 is an important factor in the development of experimental CM.

scholarly journals Interleukin 12 induces stable priming for interferon gamma (IFN-gamma) production during differentiation of human T helper (Th) cells and transient IFN-gamma production in established Th2 cell clones.

1994 ◽  
Vol 179 (4) ◽  
pp. 1273-1283 ◽  
Author(s):  
R Manetti ◽  
F Gerosa ◽  
M G Giudizi ◽  
R Biagiotti ◽  
P Parronchi ◽  
...  
Keyword(s):  
T Cells ◽  
Interferon Gamma ◽  
Specific Antigen ◽  
Th2 Cells ◽  
Interleukin 12 ◽  
T Helper ◽  
Ifn Gamma ◽  
Selection Of

Interleukin 12 (IL-12) facilitates the generation of a T helper type 1 (Th1) response, with high interferon gamma (IFN-gamma) production, while inhibiting the generation of IL-4-producing Th2 cells in polyclonal cultures of both human and murine T cells and in vivo in the mouse. In this study, we analyzed the effect of IL-12, present during cloning of human T cells, on the cytokine profile of the clones. The culture system used allows growth of clones from virtually every T cell, and thus excludes the possibility that selection of precommitted Th cell precursors plays a role in determining characteristics of the clones. IL-12 present during the cloning procedures endowed both CD4+ and CD8+ clones with the ability to produce IFN-gamma at levels severalfold higher than those observed in clones generated in the absence of IL-12. This priming was stable because the high levels of IFN-gamma production were maintained when the clones were cultured in the absence of IL-12 for 11 d. The CD4+ and some of the CD8+ clones produced variable amounts of IL-4. Unlike IFN-gamma, IL-4 production was not significantly different in clones generated in the presence or absence of IL-12. These data suggest that IL-12 primes the clone progenitors, inducing their differentiation to high IFN-gamma-producing clones. The suppression of IL-4-producing cells observed in polyclonally generated T cells in vivo and in vitro in the presence of IL-12 is not observed in this clonal model, suggesting that the suppression depends more on positive selection of non-IL-4-producing cells than on differentiation of individual clones. However, antigen-specific established Th2 clones that were unable to produce IFN-gamma with any other inducer did produce IFN-gamma at low but significant levels when stimulated with IL-12 in combination with specific antigen or insoluble anti-CD3 antibodies. This induction of IFN-gamma gene expression was transient, because culture of the established clones with IL-12 for up to 1 wk did not convert them into IFN-gamma producers when stimulated in the absence of IL-12. These results suggest that Th clones respond to IL-12 treatment either with a stable priming for IFN-gamma production or with only a transient low level expression of the IFN-gamma gene, depending on their stage of differentiation.

IL-24 protects againstSalmonella typhimuriuminfection by stimulating early neutrophil Th1 cytokine production, which in turn activates CD8+T cells

2009 ◽  
Vol 39 (12) ◽  
pp. 3357-3368 ◽  
Author(s):  
Yunfeng Ma ◽  
Haidan Chen ◽  
Qilong Wang ◽  
Fengling Luo ◽  
Jun Yan ◽  
...  
Keyword(s):  
T Cells ◽  
Cd8 T Cells ◽  
Cytokine Production ◽  
Th1 Cytokine

scholarly journals Role of accessory cells in cytokine production by T cells in chronic B- cell lymphocytic leukemia

Blood ◽  
1995 ◽  
Vol 86 (3) ◽  
pp. 1115-1123 ◽  
Author(s):  
T Decker ◽  
T Flohr ◽  
P Trautmann ◽  
MJ Aman ◽  
W Holter ◽  
...  
Keyword(s):  
T Cells ◽  
B Cell ◽  
T Helper Cells ◽  
Cytokine Production ◽  
Lymphocytic Leukemia ◽  
T Helper ◽  
Ifn Gamma ◽  
Helper Cells ◽  
Accessory Cells ◽  
Normal Individuals

Abstract We investigated the production of cytokines by highly purified T helper cells from B-cell chronic lymphocytic leukemia (B-CLL) patients stimulated by different activation pathways, and we studied the influence of various accessory cell populations on the pattern of the secretion of cytokines, including interleukin (IL)-2, IL-4, interferon- gamma (IFN-gamma), and IL-10. Neither a qualitative nor a quantitative difference in cytokine production and proliferative capacity was observed in CLL-derived purified T cells compared with normal individuals, when T cells were stimulated by different pathways, including CD3, CD2, and costimulation with CD28. Addition of autologous accessory cells (aAC), however, dramatically influenced the cytokine pattern of normal versus B-CLL-derived T cells. CLL cells as aAC caused a marked increase of IL-2, whereas IFN-gamma was only slightly induced and IL-4 was not influenced. In contrast, in normal individuals addition of aAC, which predominantly consisted of monocytes, resulted in a significant increase of IFN-gamma and a reduction of IL-4 secretion. IL-2 production was inhibited by higher concentrations of aAC. The increased stimulation of IL-2 production by CLL cells was not specific to the leukemic cell population, as purified B cells from normal individuals had the same effect. On the other hand, purified monocytes from CLL patients and controls both induced IFN-gamma production and inhibited IL-4 secretion. After antigen-specific stimulation with tetanus toxoid, cytokine secretion was influenced by the type of aAC in a similar pattern. We conclude that T helper cells derived from patients with B-CLL are intrinsically normal and that the predominance of B cells as accessory cells in CLL significantly alters the immune function of T helper cells in vitro.

scholarly journals Cytokine interactions in human immunodeficiency virus-infected individuals: roles of interleukin (IL)-2, IL-12, and IL-15.

1995 ◽  
Vol 182 (4) ◽  
pp. 1067-1077 ◽  
Author(s):  
R A Seder ◽  
K H Grabstein ◽  
J A Berzofsky ◽  
J F McDyer
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Tetanus Toxoid ◽  
Cd4 T Cells ◽  
Mononuclear Cells ◽  
Specific Antigen ◽  
Neutralizing Antibody ◽  
Dependent Manner ◽  
Ifn Gamma ◽  
Immunodeficiency Virus

Cytokines have been shown to be powerful regulators of the immune response. In this study, we analyze the effect that the newly recognized cytokine interleukin (IL)-15 has on proliferation and cytokine induction using peripheral blood mononuclear cells (PBMCs) and purified CD4+ T cells from patients infected with human immunodeficiency virus (HIV) who are at various stages in their disease. We observed that IL-15 enhances the proliferative response in a dose-dependent manner from PBMCs of HIV-infected individuals when stimulated by polyclonal mitogen, tetanus toxoid, or HIV-specific antigen. The effects of exogenous IL-15 are substantially diminished by adding a neutralizing antibody to the beta chain of the IL-2 receptor. Moreover, the ability of IL-15 to increase proliferation is enhanced by the presence of endogenous IL-2 produced in the cultures. The effect that exogenous IL-15 had on IL-2, IL-4, and interferon (IFN)-gamma induction from PBMC's or CD4+ T cells in response to mitogen or tetanus toxoid was also examined. This was compared to the effect that exogenous IL-2 and IL-12 had under the same conditions. Addition of IL-2 or IL-15 to short-term in vitro cultures of either PBMCs or CD4+ T cells had little effect on IL-2, IL-4, or IFN-gamma production. By contrast, IL-12 caused substantial enhancement of both IL-2 and IFN-gamma production from these cultures. The role that endogenous cytokines have on IFN-gamma induction was also studied. Addition of a neutralizing antibody to the alpha chain of the IL-2 receptor or IL-12 to antigen stimulated cultures caused a striking decrease in IFN-gamma production. Neutralization of endogenous IL-15 also resulted in diminished IFN-gamma production from cultures stimulated with mitogen. IL-4 and IFN-gamma protein production by PBMCs and CD4+ T cells stimulated with mitogen was assessed to see if we could detect a specific bias of cytokine production. Small amounts of IL-4 were detected from CD4+ T cells but not PBMCs from most individuals tested. IFN-gamma and IL-2, however, were also produced from these same cultures. These results further elucidate the mechanism of cytokine regulation in HIV-infected individuals, and they provide evidence that IL-15 may be a useful immune modulator.

Cytokine Production and Proliferation in Mixed Lymphocyte Culture (MLC) May Predict Donor Engraftment in Adult Recipients of Multiple Umbilical Cord Blood (UCB) Unit Transplantation.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1832-1832
Author(s):  
L. R. Fanning ◽  
M. Tary-Lehmann ◽  
J. Jaroscak ◽  
P. Rubinstein ◽  
T. McCormick ◽  
...  
Keyword(s):  
Cytokine Production ◽  
Mixed Lymphocyte Culture ◽  
Lymphocyte Culture ◽  
Hla Typing ◽  
Th2 Cytokines ◽  
Hla Antigen ◽  
Th1 Response ◽  
Cell Dose ◽  
Th1 Cytokine ◽  
Th1 Cytokines

Abstract Limited cell dose within a single UCB graft provides the rationale for multiple UCB unit transplantation. Our single institution phase I study testing the safety and efficacy of multiple UCB unit infusion targeted a nucleated cell dose of minimum ≥ 5x107cells/kg, and patients were transplanted with 3-5 unrelated UCB units. Seven adult patients (median 56 years; range 20–69) with advanced hematologic malignancies (4 AML, 1 ALL, 2 NHL) were enrolled and treated with non-myelablative conditioning including Fludarabine 150mg/m2, Cyclophosphamide 2gm/m2, and ATGAM 60mg/kg. UCB grafts were not T-depleted. All UCB units were 1-2 HLA antigen mismatched with the patient, and HLA matching between units was not required. The patients were transplanted sequentially and received a median infused total nucleated cell dose: 5.4x107/kg (range 4.2–8.9), CD3+: 1.4x107/kg (range 1.4–3.4), and CD34+: 2.2x105/kg (range 1.9–5.3). Three of the 7 patients demonstrated UCB donor engraftment while 3 patients had autologous recovery, and one patient died prior to engraftment (day=56). Mixed lymphocyte culture (MLC) was performed including proliferation and cytokine production in order to evaluate impact of graft-graft and patient-graft immune reactivity on donor engraftment. Cryogenically preserved pre-transplant patient and corresponding UCB graft samples were thawed for MLC with readouts including proliferation (CFSE staining) and cytokine production (cytometric bead assay-CBA)(Becton Dickinson, Franklin Lakes, NJ) including pro-inflammatory TH1 cytokines (IFN-γ, TNF-α, IL-2) and anti-inflammatory TH2 cytokines (IL-10, IL-5, IL-4). We hypothesize that increased proliferation and a strong TH1 response may be detrimental to engraftment which was confirmed by preliminary analysis (n=4). We observed higher rates of proliferation as well as higher TH1 cytokine production within the MLC of patients who did not attain donor engraftment. Table 1: TH1 Cytokine Output and Proliferation of Patient and Graft Mixed Lymphocyte Cultures Patient Number Number of UCB Units Donor Engraftment IFNγ(pg/mL) TNFα (pg/mL) IL-2(pg/mL) % Proliferation Pt #1 5 No 940 226 79 16 Pt #2 3 No 234 56 46 20 Pt #3 3 Yes 32 <20 <20 9 Pt #4 5 Yes <20 <20 <20 N/A TH1 cytokines produced in graft-graft MLCs were also elevated in the non-engrafting patients over those of the engrafting patients. The TH1 response of graft-graft interactions was lower than patient-graft interactions, indicating a bi-directional immune response. PHA positive controls indicate the decreased TH1 cytokine production seen in engrafted patients was not due to an inability to be activated. No trends were identified in the TH2 cytokines measured. These preliminary results suggest that graft-graft immune interactions as well as patient-graft interactions may determine overall donor engraftment. We plan to prospectively test this hypothesis in our ongoing clinical trial. MLCs with TH1 cytokine readouts that are patient and UCB unit specific may predict donor engraftment after multiple unit infusion and may be used as an adjunct to HLA typing.

Th2 Polarization Induced by the Farnesyltransferase Inhibitor Tipifarnib (Zarnestra®, R115777) through Suppression of T-bet.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1331-1331
Author(s):  
Fanqi Bai ◽  
J.-X. Zou ◽  
Sheng Wei ◽  
Jeffrey S. Painter ◽  
Michelle Blaskovich ◽  
...  
Keyword(s):  
T Cells ◽  
Cytokine Production ◽  
Immunosuppressive Agents ◽  
Cytokine Signaling ◽  
Th2 Cytokines ◽  
Western Blots ◽  
Healthy Donors ◽  
Th2 Polarization ◽  
Th1 And Th2 ◽  
Lgl Leukemia

Abstract BACKGROUND: LGL leukemia is a neoplasm arising from either CD3+ T-cells or CD3− NK-cells. Autoimmune-mediated anemia, neutropenia, and rheumatoid arthritis occur frequently in these patients and immunosuppressive agents are used for these associated clinical syndromes. In our previous studies, we found that patients display a constitutively activated Ras and MAPK/ERK signaling cascade that may drive leukemia survival. A multicenter phase 2 clinical trial was initiated to treat LGL leukemia patients with the farnysltransferase-inhibitor R115777 (tipifarnib, Zarnestra®, Johnson & Johnson) that inhibits Ras and other farnesylated proteins. One of the goals of this study was to determine the shifts in cytokine production during therapy. We found that LGL cells treated with tipifarnib in vitro displayed a switch to Th2 (IL-4 and IL-10)-polarized differentiation. After tipifarnib treatment of LGL patients, antigen-activated T-cells produced greater amounts of Th2 (IL4/IL-10) cytokines but less Th1 (IFNγ/TNFα). In this study, we determined the mechanism governing tipifarnib-mediated Th2 polarization in T-cells. METHODS: PBMCs were isolated from 10 healthy donors and from seven patients with T-LGL leukemia before and after treatment with tipifarnib 300 mg twice daily for 21 days of a 28- day cycle. LGL leukemia patients had increased numbers of αβ T lymphocytes and evidence of clonality in association with either neutropenia or transfusion-dependent anemia. Th1 and Th2 cytokines were determined by intracellular staining and flow cytometry after activation with anti-CD3 plus anti-CD28. In some experiments, Th1 polarization was induced by IL-12; whereas, Th2 was induced by IL-4. Expression of T-bet and GATA-3 transcription factors that regulate Th1 and Th2 polarization, respectively, phosphorylated (active) MAPK (ERK1 and ERK2), and total MAPK were measured by Western blots. FTI2153, tipifarnib, and geranylgeranyl transferase inhibitor(GGTI)-2417 were used compared to DMSO control. RESULTS: PBMCs from patients with T-LGL leukemia displayed a dose and time-dependent increase in IL-4 and IL-10 production after drug treatment (average increase to 100% and 43%, respectively). A dose-dependent increase in these Th2 cytokines in T-cells from healthy donors showed that the farnesylated protein targeted by tipifarnib was not selectively expressed in LGL leukemia. Culture with IL-12 induced Th1 differentiation associated with ERK phosphorylation and increased T-bet expression. Pre-treatment with tipifarnib and FTI2153 but not GGTI2417 prior to IL-12 inhibited T-bet induction with no change in anti-CD3-induced MAPK leading to enhanced IL-4 signaling and greater Th2 polarization. CONCLUSIONS: Our data reveal unique, previously unreported effects of FTIs on cytokine signaling in T-cells by inhibiting the induction of T-bet and blocking Th1 differentiation. These results are critical to determine the mechanism of action of tipifarnib in LGL leukemia and suggest that FTIs may be useful for autoimmune or lymphocyte-mediated disorders associated with excessive Th1 cytokine production.

scholarly journals Helicobacter pylori Promotes the Production of Thymic Stromal Lymphopoietin by Gastric Epithelial Cells and Induces Dendritic Cell-Mediated Inflammatory Th2 Responses

2009 ◽  
Vol 78 (1) ◽  
pp. 108-114 ◽  
Author(s):  
Masahiro Kido ◽  
Junya Tanaka ◽  
Nobuhiro Aoki ◽  
Satoru Iwamoto ◽  
Hisayo Nishiura ◽  
...  
Keyword(s):  
T Cells ◽  
Epithelial Cells ◽  
B Cell ◽  
Cell Activation ◽  
Th2 Cytokines ◽  
Gastric Epithelial Cells ◽  
B Cell Activation ◽  
Th2 Responses ◽  
H Pylori ◽  
Follicular Gastritis

ABSTRACT Helicobacter pylori colonizes the stomach and induces strong, specific local and systemic humoral and cell-mediated immunity, resulting in the development of chronic gastritis in humans. Although H. pylori-induced chronic atrophic gastritis is characterized by marked infiltration of T helper type 1 (Th1) cytokine-producing CD4+ T cells, almost all of the inflamed gastric mucosae also contain focal lymphoid aggregates with germinal centers. In addition, typical H. pylori-induced chronic gastritis in children, called follicular gastritis, is characterized by B-cell follicle formation in the gastric mucosa. The aim of this study was to examine whether thymic stromal lymphopoietin (TSLP), an epithelial-cell-derived cytokine inducing a dendritic cell (DC)-mediated inflammatory Th2 response, is involved in Th2 responses triggering B-cell activation in H. pylori-induced gastritis. Here, we show that H. pylori triggered human gastric epithelial cells to produce TSLP, together with the DC-attracting chemokine MIP-3α and the B-cell-activating factor BAFF. After DCs were incubated with supernatants from H. pylori-infected epithelial cells, the conditioned cells expressed high levels of costimulatory molecules, such as CD80, and triggered naïve CD4+ T cells to produce high levels of the Th2 cytokines interleukin-4 and interleukin-13 and of the inflammatory cytokines tumor necrosis factor alpha and gamma interferon. In contrast, after incubation of the supernatants with the neutralizing antibodies to TSLP, the conditioned DCs did not prime T cells to produce high levels of Th2 cytokines. These results, together with the finding that TSLP was expressed by the epithelial cells of human follicular gastritis, suggest that H. pylori can directly trigger epithelial cells to produce TSLP. It also suggests that TSLP-mediated DC activation may be involved in Th2 responses triggering B-cell activation in H. pylori-induced gastritis.

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