LIPOPOLYSACCHARIDE STIMULATION OF DENDRITIC CELLS INDUCES INTERLEUKIN-10 PRODUCING ALLERGEN-SPECIFIC T CELLS IN VITRO BUT FAILS TO PREVENT ALLERGIC AIRWAY DISEASE

ABSTRACT We have previously shown that very few rotavirus (RV)-specific T cells that secrete gamma interferon circulate in recently infected and seropositive adults and children. Here, we have studied the interaction of RV with myeloid immature (IDC) and mature dendritic cells (MDC) in vitro. RV did not induce cell death of IDC or MDC and induced maturation of between 12 and 48% of IDC. Nonetheless, RV did not inhibit the maturation of IDC or change the expression of maturation markers on MDC. After treatment with RV, few IDC expressed the nonstructural viral protein NSP4. In contrast, a discrete productive viral infection was shown in MDC of a subset of volunteers, and between 3 and 46% of these cells expressed NSP4. RV-treated IDC secreted interleukin 6 (IL-6) (but not IL-1β, IL-8, IL-10, IL-12, tumor necrosis factor alpha, or transforming growth factor beta), and MDC released IL-6 and small amounts of IL-10 and IL-12p70. The patterns of cytokines secreted by T cells stimulated by staphylococcal enterotoxin B presented by MDC infected with RV or uninfected were comparable. The frequencies and patterns of cytokines secreted by memory RV-specific T cells evidenced after stimulation of peripheral blood mononuclear cells (PBMC) with RV were similar to those evidenced after stimulation of PBMC with RV-infected MDC. Finally, IDC treated with RV strongly stimulated naive allogeneic CD4+ T cells to secrete Th1 cytokines. Thus, although RV does not seem to be a strong maturing stimulus for DC, it promotes their capacity to prime Th1 cells.

Download Full-text

Extract and fractions from birch bark affect stimulation of human dendritic cells and their activation of allogeneic CD4+ T cells in vitro

Planta Medica ◽

10.1055/s-0030-1264940 ◽

2010 ◽

Vol 76 (12) ◽

Author(s):

S Omarsdottir ◽

M Sigurpalsson ◽

A Eggertsdottir ◽

J Runarsson ◽

I Hardardottir ◽

...

Keyword(s):

T Cells ◽

Dendritic Cells ◽

Cd4 T Cells ◽

Birch Bark ◽

Human Dendritic Cells ◽

Stimulation Of

Download Full-text

Generation of Leukemia-Derived Dendritic Cells (DCleu) as a Basis for Specific Immunotherapy in Acute Myeloid Leukemia (AML) and Myelodysplastic Syndrome (MDS).

Blood ◽

10.1182/blood.v104.11.2547.2547 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2547-2547

Author(s):

Helga Schmetzer ◽

Christoph Schmid ◽

Susanne Kufner ◽

Renate Pelka-Fleischer ◽

Tanja Kroell ◽

...

Keyword(s):

T Cells ◽

Dendritic Cells ◽

T Cell ◽

Cell Response ◽

T Cell Response ◽

Aberrant Expression ◽

Immune Phenotype ◽

Cytogenetic Aberrations ◽

Stimulation Of

Abstract The presentation of leukemic antigens can be improved in AML and MDS by in vitro generation of dendritic cells of leukemic origin (DCleu), thereby creating a platform for the generation of leukemia-specific cytotoxic lymphocytes (CTL). To further investigate this approach, we developed a serum-free culture system using MCM-Mimic medium (X-vivo + GM-GSF + IL-4 + FL + IL1β + IL-6 + TNFα + PGE2) for differentiation of malignant myeloid blasts to DCleu. Periperal blood mononuclear cells (PB-MNC) were obtained from 100 AML and 55 MDS-patients. Samples contained a mean of 59%/and 6% of blasts, respectively. After 14 days, cultures contained on average 34% (AML) and 20%(MDS) DC. DC yields were best in monocytic subtypes (AML M4, M5 and CMML). Cytogenetic aberrations of the leukemia had no influence. The leukemic origin of cultured DC was demonstrated using a acombined FISH/immune phenotyping assay (FISH/IPA): In cells showing a characteristic DC morphology and immune phenotype, FISH was used to detect specific cytogenetic aberrations identified in the leukemic population at time of diagnosis. Alternativly, DCleu were identified by detecting coexpression of DC markers and a leukemia-specific immune phenotype (as defined by aberrant expression of lineage markers or a characteristic CD34+/CD117+ phenotype in MDS). However, in most cases not all leukemic blasts in a given sample could be differentiated, since on average 47% of clonal cells did not acquire a DC-like immunophenotype. Vice versa, not all DC identified at the end of the culture period were DCleu. The capacity of DCleu to elicit a specific T-cell response was demonstrated by upregulation of contact-molecules, responsible for DC/T-cell contact, by DC-activated T-cell proliferation and by the capacity of DC-activated T-cells to specifically lyse naive blasts. In 6%/31% of AML/MDS-cases, <10% DC could be generated. Therefore, other DC-culture-assays were compared with respect to DC harvest, to identify the best method for DC-generation in each individual patient. Compared to `MCM-Mimic`, harvest of DC could be improved by `CA-Ionophore-media`(A23187 + Il4) in 4 of 7 cases, whereas in 3 cases, MCM led to higher DC-yields. In conclusion, DCleu can be generated in the majority of patients with AML and MDS. To optimize DC harvest for in vitro and in vivo use, different culture assays should be compared in each individual case. DCleu are able to elicit a specific T-cell response in vitro. Nevertheless, cultures containing DCleu also contain relevant numbers of undifferentiated blasts and DC of non-leukemic origin. These cells may represent an obstacle for the clinical use of DCleu, since they may cause specific anergy or unspecific stimulation of effector T-cells. Improvement of culture conditions for generation of DCleu, and methods to separate DCleu before stimulation of effector cells will be required, before clinical trials are feasible.

Download Full-text

Stimulation of Dendritic Cells via CD40 Enhances Immune Responses to Mycobacterium tuberculosisInfection

Infection and Immunity ◽

10.1128/iai.69.4.2456-2461.2001 ◽

2001 ◽

Vol 69 (4) ◽

pp. 2456-2461 ◽

Cited By ~ 43

Author(s):

Caroline Demangel ◽

Umaimainthan Palendira ◽

Carl G. Feng ◽

Andrew W. Heath ◽

Andrew G. D. Bean ◽

...

Keyword(s):

T Cells ◽

Dendritic Cells ◽

Immune Responses ◽

Protective Efficacy ◽

Interleukin 12 ◽

Ifn Γ ◽

Cellular Immune ◽

Stimulation Of

ABSTRACT The resolution of pulmonary tuberculosis (TB) critically depends on the development of the Th1 type of immune responses, as exemplified by the exacerbation of TB in IL-12-deficient mice. Therefore, vaccination strategies optimizing IL-12 production by antigen-presenting cells (APC) in response to mycobacteria may have enhanced protective efficacy. Since dendritic cells (DC) are the critical APC for activation of CD4+ and CD8+ T cells, we examined whether stimulation of Mycobacterium bovis bacillus Calmette Guérin (BCG)-infected DC via CD40 increased their ability to generate Th1-oriented cellular immune responses. Incubation of DC with an agonistic anti-CD40 antibody activated CD40 signaling in DC, as shown by increased expression of major histocompatibility complex class II and costimulatory molecules, mRNA production for proinflammatory cytokines and interleukin 12 (IL-12) p40. This activation pattern was maintained when DC were stimulated with anti-CD40 antibody and infected with BCG. Importantly, CD40-stimulated BCG-infected DC displayed increased capacity to release bioactive IL-12 and to activate gamma interferon (IFN-γ) producing T cells in vitro. Moreover, when C57BL/6 mice were immunized with these DC and challenged with aerosol Mycobacterium tuberculosis, increased levels of mRNA for IL-12 p40, IL-18, and IFN-γ were present in the draining mediastinal lymph nodes. However, the mycobacterial burden in the lungs was not reduced compared to that in mice immunized with BCG-infected non-CD40-stimulated DC. Therefore, although the manipulation of DC via CD40 is effective for enhancing immune responses to mycobacteria in vivo, additional strategies are required to increase protection against virulent M. tuberculosis infection.

Download Full-text

Cotransfection of Dendritic Cells with RNA Coding for a Tumor Antigen and Costimulatory Molecule 4-1BBL Increases the Induction of Her-2/neu Specific Cytotoxic T-Cells.

Blood ◽

10.1182/blood.v104.11.1352.1352 ◽

2004 ◽

Vol 104 (11) ◽

pp. 1352-1352

Author(s):

Frank Grünebach ◽

Katrin Kayser ◽

Silke Appel ◽

Markus M. Weck ◽

Martin R. Müller ◽

...

Keyword(s):

T Cells ◽

Dendritic Cells ◽

T Cell ◽

Cell Line ◽

Cytotoxic T Cells ◽

Specific Lysis ◽

Stimulatory Capacity ◽

Her 2 ◽

Stimulation Of

Abstract Dendritic cells are professional antigen-presenting cells (APC) with the unique capacity to initiate primary immune responses. Recently, it was demonstrated that transfection of DC with RNA coding for specific antigens can elicit an effective T cell response in vitro and in vivo. 4-1BB (CD137) is a member of a family of receptors found on the surface of cells of the immune system. It plays an important role in the costimulation of T-cells: it enhances T-cell proliferation, cytokine production and cytotoxic effector functions and suppresses the induction of apoptosis. It is predominantly expressed on activated T-cells, and its ligand 4-1BBL is expressed on activated APC including DC. In the present study we analyzed the effects of 4-1BBL on the stimulatory capacity of DC. Monocyte derived DC were electroporated with in vitro transcribed RNA encoding the tumor-associated antigen Her-2/neu. Additionally these cells were cotransfected with in vitro transcribed RNA coding for the human 4-1BBL with the aim to enhance the costimulatory functions of the cells and therefore the induction of Her-2/neu specific cytotoxic T-cells (CTL). Standard 51Cr-release assays performed after two restimulations showed specific cytotoxic activity of the induced CTL against autologous DC transfected with Her-2/neu RNA and against the HLA-matched allogeneic Her-2/neu+/HLA-A2+ renal cell carcinoma cell line A498 whereas DC transfected with irrelevant RNA as well as Her-2/neu-/HLA-A2+ CROFT cells and the Her-2/neu+/HLA-A2- cell line SK-OV-3 were spared. There was no lysis of K562 cells, thus excluding a NK-cell mediated killing. In this experimental setting the specific lysis rate of target cells could nearly be doubled by the coadministration of Her-2/neu RNA and an equal amount of 4-1BBL RNA (50% vs 90% specific lysis at effector to target ratio of 30:1). Interestingly, overexpression of 4-1BBL had no effect on the stimulation of allogeneic T cells by electroporated DC in a mixed lymphocyte reaction, indicating that 4-1BBL increases the induction of antigen specific T cell responses rather than the unspecific stimulation of bulk T lymphocytes. Furthermore, FACS analysis of DC transfected with 4-1BBL plasmid DNA or in vitro transcribed 4-1BBL RNA showed higher expression of the costimulatory molecules CD80, CD86, CD40 and the T-cell adhesion molecule CD54 as compared to the controls indicating that 4-1BBL signaling can mediate activation of DC and thus increase their stimulatory capacity. In the context of immunotherapies for cancer patients the findings of our study could contribute to optimise the in vitro manipulation of DC for the induction of antigen-specific CTL responses.

Download Full-text

Interleukin 10 Gene-Modified Bone Marrow-Derived Dendritic Cells Attenuate Liver Fibrosis in Mice by Inducing Regulatory T Cells and Inhibiting the TGF-β/Smad Signaling Pathway

Mediators of Inflammation ◽

10.1155/2019/4652596 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15 ◽

Cited By ~ 5

Author(s):

Yejin Xu ◽

Xinyue Tang ◽

Min Yang ◽

Shengguo Zhang ◽

Shanshan Li ◽

...

Keyword(s):

Bone Marrow ◽

T Cells ◽

Dendritic Cells ◽

Liver Fibrosis ◽

Regulatory T Cells ◽

Interleukin 10 ◽

Smad Signaling Pathway ◽

Culture Supernatants

Aim. To explore the therapeutic effects and mechanisms of interleukin 10 gene-modified bone marrow-derived dendritic cells (DC-IL10) on liver fibrosis. Methods. In vitro, BMDCs were transfected with lentiviral-interleukin 10-GFP (LV-IL10-GFP) at the MOI of 1 : 40. Then, the phenotype (MHCII, CD80, and CD86) and allo-stimulatory ability of DC-IL10 were identified by flow cytometry, and the levels of IL-10 and IL-12 (p70) secreted into the culture supernatants were quantified by ELISA. In vivo, DC-IL10 was injected into mice with CCl4-induced liver fibrosis through the tail vein. Lymphocytes were isolated to investigate the differentiation of T cells, and serum and liver tissue were collected for biochemical, cytokine, histopathologic, immune-histochemical, and Western blot analyzes. Results. In vitro, the expressions of MHCII, CD80, and CD86 in DC-IL10 were significantly suppressed, allogeneic CD4+T cells incubated with DC-IL10 showed a lower proliferative response, and the levels of IL-10 and IL-12 (p70) secreted into the DC-IL10 culture supernatants were significantly increased and decreased, respectively. In vivo, regulatory T cells (Tregs) were significantly increased, while ALT, AST, and inflammatory cytokines were significantly reduced in the DC-IL10 treatment group, and the degree of hepatic fibrosis was obviously reversed. The TGF-β/smad pathway was inhibited following DC-IL10 treatment compared to the liver fibrosis group. Conclusion. IL-10 genetic modification of BMDCs may maintain DC in the state of tolerance and allow DC to induce T cell hyporesponsiveness or tolerance. DC-IL10 suppressed liver fibrosis by inducing Treg production and inhibiting the TGF-β/smad signaling pathway.

Download Full-text