scholarly journals Dendritic Cells Discriminate between Yeasts and Hyphae of the Fungus Candida albicans

2000 ◽  
Vol 191 (10) ◽  
pp. 1661-1674 ◽  
Author(s):  
Cristiana Fè d'Ostiani ◽  
Giuseppe Del Sero ◽  
Angela Bacci ◽  
Claudia Montagnoli ◽  
Antonio Spreca ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Candida Albicans ◽  
Ex Vivo ◽  
T Helper ◽  
Myeloid Dendritic Cells ◽  
Mucosal Surfaces ◽  
A Cell

The fungus Candida albicans behaves as a commensal as well as a true pathogen of areas highly enriched in dendritic cells, such as skin and mucosal surfaces. The ability of the fungus to reversibly switch between unicellular yeast to filamentous forms is thought to be important for virulence. However, whether it is the yeast or the hyphal form that is responsible for pathogenicity is still a matter of debate. Here we show the interaction, and consequences, of different forms of C. albicans with dendritic cells. Immature myeloid dendritic cells rapidly and efficiently phagocytosed both yeasts and hyphae of the fungus. Phagocytosis occurred through different phagocytic morphologies and receptors, resulting in phagosome formation. However, hyphae escaped the phagosome and were found lying free in the cytoplasm of the cells. In vitro, ingestion of yeasts activated dendritic cells for interleukin (IL)-12 production and priming of T helper type 1 (Th1) cells, whereas ingestion of hyphae inhibited IL-12 and Th1 priming, and induced IL-4 production. In vivo, generation of antifungal protective immunity was induced upon injection of dendritic cells ex vivo pulsed with Candida yeasts but not hyphae. The immunization capacity of yeast-pulsed dendritic cells was lost in the absence of IL-12, whereas that of hypha-pulsed dendritic cells was gained in the absence of IL-4. These results indicate that dendritic cells fulfill the requirement of a cell uniquely capable of sensing the two forms of C. albicans in terms of type of immune responses elicited. By the discriminative production of IL-12 and IL-4 in response to the nonvirulent and virulent forms of the fungus, dendritic cells appear to meet the challenge of Th priming and education in C. albicans saprophytism and infections.

scholarly journals Selective Expression and Functions of Interleukin 18 Receptor on T Helper (Th) Type 1 but not Th2 Cells

1998 ◽  
Vol 188 (8) ◽  
pp. 1485-1492 ◽  
Author(s):  
Damo Xu ◽  
Woon Ling Chan ◽  
Bernard P. Leung ◽  
David Hunter ◽  
Kerstin Schulz ◽  
...  
Keyword(s):  
Th2 Cells ◽  
Interleukin 18 ◽  
T Helper ◽  
Th2 Cell ◽  
A Cell ◽  
Ifn Γ

Interleukin (IL)-18 induces interferon (IFN)-γ synthesis and synergizes with IL-12 in T helper type 1 (Th1) but not Th2 cell development. We report here that IL-18 receptor (IL-18R) is selectively expressed on murine Th1 but not Th2 cells. IL-18R mRNA was expressed constitutively and consistently in long-term cultured clones, as well as on newly polarized Th1 but not Th2 cells. IL-18 sustained the expression of IL-12Rβ2 mRNA, indicating that IL-18R transmits signals that maintain Th1 development through the IL-12R complex. In turn, IL-12 upregulated IL-18R mRNA. Antibody against an IL-18R–derived peptide bound Th1 but not Th2 clones. It also labeled polarized Th1 but not Th2 cells derived from naive ovalbumin–T cell antigen receptor-αβ transgenic mice (D011.10). Anti–IL-18R antibody inhibited IL-18– induced IFN-γ production by Th1 clones in vitro. In vivo, anti–IL-18R antibody reduced local inflammation and lipopolysaccharide-induced mortality in mice. This was accompanied by shifting the balance from Th1 to Th2 responses, manifest as decreased IFN-γ and proinflammatory cytokine production and increased IL-4 and IL-5 synthesis. Therefore, these data provide a direct mechanism for the selective effect of IL-18 on Th1 but not Th2 cells. They also show that the synergistic effect of IL-12 and IL-18 on Th1 development may be due to the reciprocal upregulation of their receptors. Furthermore, IL-18R is a cell surface marker distinguishing Th1 from Th2 cells and may be a therapeutic target.

scholarly journals Neem Leaf Glycoprotein Partially Rectifies Suppressed Dendritic Cell Functions and Associated T Cell Efficacy in Patients with Stage IIIB Cervical Cancer

2011 ◽  
Vol 18 (4) ◽  
pp. 571-579 ◽  
Author(s):  
Soumyabrata Roy ◽  
Shyamal Goswami ◽  
Anamika Bose ◽  
Krishnendu Chakraborty ◽  
Smarajit Pal ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Dendritic Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Stage Iiib ◽  
Immune Functions ◽  
Cell Functions

ABSTRACTMyeloid-derived dendritic cells (DCs) generated from monocytes obtained from stage IIIB cervical cancer (CaCx IIIB) patients show dysfunctional maturation; thus, antitumor T cell functions are dysregulated. In an objective to optimize these dysregulated immune functions, the present study is focused on the ability of neem leaf glycoprotein (NLGP), a nontoxic preparation of the neem leaf, to induce optimum maturation of dendritic cells from CaCx IIIB patients.In vitroNLGP treatment of immature DCs (iDCs) obtained from CaCx IIIB patients results in upregulated expression of various cell surface markers (CD40, CD83, CD80, CD86, and HLA-ABC), which indicates DC maturation. Consequently, NLGP-matured DCs displayed balanced cytokine secretions, with type 1 bias and noteworthy functional properties. These DCs displayed substantial T cell allostimulatory capacity and promoted the generation of cytotoxic T lymphocytes (CTLs). Although NLGP-matured DCs derived from CaCx monocytes are generally subdued compared to those with a healthy monocyte origin, considerable revival of the suppressed DC-based immune functions is notedin vitroat a fairly advanced stage of CaCx, and thus, further exploration ofex vivoandin vivoDC-based vaccines is proposed. Moreover, the DC maturating efficacy of NLGP might be much more effective in the earlier stages of CaCx, where the extent of immune dysregulation is less and, thus, the scope of further investigation may be explored.

scholarly journals Antigen-pulsed dendritic cells can efficiently induce an antibody response in vivo.

1992 ◽  
Vol 175 (1) ◽  
pp. 15-21 ◽  
Author(s):  
T Sornasse ◽  
V Flamand ◽  
G De Becker ◽  
H Bazin ◽  
F Tielemans ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Antibody Response ◽  
Interleukin 2 ◽  
Humoral Response ◽  
T Helper ◽  
Pulsed Dc ◽  
Immunization Procedure

The aim of this study was to develop an immunization procedure avoiding external adjuvant. Data are presented showing that syngeneic dendritic cells (DC), which have been pulsed in vitro with antigen, induce a strong antibody response in mice. By contrast, antigen (Ag)-pulsed low-density B cells, although equally able to induce interleukin 2 secretion by an Ag-specific T cell hybridoma in vitro, only weakly prime the mice in vivo. Moreover, we show that the injection of Ag-pulsed DC induces the synthesis of isotypes similar to the immunoglobulin classes detected after immunization with the same Ag in complete Freund's adjuvant. Importantly, high amounts of IgG2a antibodies are produced, suggesting that T helper type 1 cells are activated. Collectively, these data indicate that DC can initiate a primary humoral response and that they may be used as physiological adjuvant in vivo.

scholarly journals Endogenous Interleukin 4 Is Required for Development of Protective CD4+ T Helper Type 1 Cell Responses to Candida albicans

1998 ◽  
Vol 187 (3) ◽  
pp. 307-317 ◽  
Author(s):  
Antonella Mencacci ◽  
Giuseppe Del Sero ◽  
Elio Cenci ◽  
Cristiana Fè d'Ostiani ◽  
Angela Bacci ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Early Stage ◽  
Interleukin 4 ◽  
T Helper ◽  
Ifn Γ ◽  
Deficient Mice ◽  
Helper Type

Interleukin (IL)-4–deficient mice were used to assess susceptibility to systemic or gastrointestinal Candida albicans infections, as well as parameters of innate and elicited T helper immunity. In the early stage of systemic infection with virulent C. albicans, an unopposed interferon (IFN)-γ response renders IL-4–deficient mice more resistant than wild-type mice to infection. Yet, IL-4–deficient mice failed to efficiently control infection in the late stage and succumbed to it. Defective IFN-γ and IL-12 production, but not IL-12 responsiveness, was observed in IL-4–deficient mice that failed to mount protective T helper type 1 cell (Th1)-mediated acquired immunity in response to a live vaccine strain of the yeast or upon mucosal immunization in vivo. In vitro, IL-4 primed neutrophils for cytokine release, including IL-12. However, late treatment with exogenous IL-4, while improving the outcome of infection, potentiated CD4+ Th1 responses even in the absence of neutrophils. These findings indicate that endogenous IL-4 is required for the induction of CD4+ Th1 protective antifungal responses, possibly through the combined activity on cells of the innate and adaptive immune systems.

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.

Collagen fibrous scaffolds for sustained delivery of growth factors for meniscal tissue engineering

Nanomedicine ◽  
2022 ◽  
Author(s):  
Jihye Baek ◽  
Kwang Il Lee ◽  
Ho Jong Ra ◽  
Martin K Lotz ◽  
Darryl D D'Lima
Keyword(s):  
Tissue Engineering ◽  
Growth Factors ◽  
Sustained Release ◽  
Ex Vivo ◽  
Synovial Cell ◽  
Growth Factor Delivery ◽  
Meniscal Tissue ◽  
A Cell

Aim: To mimic the ultrastructural morphology of the meniscus with nanofiber scaffolds coupled with controlled growth factor delivery to modulate cellular performance for tissue engineering of menisci. Methods: The authors functionalized collagen nanofibers by conjugating heparin to the following growth factors for sustained release: PDGF-BB, TGF-β1 and CTGF. Results: Incorporating growth factors increased human meniscal and synovial cell viability, proliferation and infiltration in vitro, ex vivo and in vivo; upregulated key genes involved in meniscal extracellular matrix synthesis; and enhanced generation of meniscus-like tissue. Conclusion: The authors' results indicate that functionalizing collagen nanofibers can create a cell-favorable micro- and nanoenvironment and can serve as a system for sustained release of bioactive factors.

scholarly journals Regulation of cilia abundance in multiciliated cells

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Rashmi Nanjundappa ◽  
Dong Kong ◽  
Kyuhwan Shim ◽  
Tim Stearns ◽  
Steven L Brody ◽  
...  
Keyword(s):  
Progenitor Cells ◽  
Surface Area ◽  
Ex Vivo ◽  
Compensatory Mechanism ◽  
Multiciliated Cells ◽  
Culture Model ◽  
A Cell ◽  
Dependent Mechanism

Multiciliated cells (MCC) contain hundreds of motile cilia used to propel fluid over their surface. To template these cilia, each MCC produces between 100-600 centrioles by a process termed centriole amplification. Yet, how MCC regulate the precise number of centrioles and cilia remains unknown. Airway progenitor cells contain two parental centrioles (PC) and form structures called deuterosomes that nucleate centrioles during amplification. Using an ex vivo airway culture model, we show that ablation of PC does not perturb deuterosome formation and centriole amplification. In contrast, loss of PC caused an increase in deuterosome and centriole abundance, highlighting the presence of a compensatory mechanism. Quantification of centriole abundance in vitro and in vivo identified a linear relationship between surface area and centriole number. By manipulating cell size, we discovered that centriole number scales with surface area. Our results demonstrate that a cell-intrinsic surface area-dependent mechanism controls centriole and cilia abundance in multiciliated cells.

Inhibitors of γ-secretase block in vivo and in vitro T helper type 1 polarization by preventing Notch upregulation of Tbx21

2005 ◽  
Vol 6 (7) ◽  
pp. 680-688 ◽  
Author(s):  
Lisa M Minter ◽  
Danielle M Turley ◽  
Pritam Das ◽  
Hyun Mu Shin ◽  
Ila Joshi ◽  
...  
Keyword(s):  
T Helper ◽  
Helper Type

Dendritic cells modified to express CD40 ligand elicit therapeutic immunity against preexisting murine tumors

Blood ◽  
2000 ◽  
Vol 96 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Toshiaki Kikuchi ◽  
Malcolm A. S. Moore ◽  
Ronald G. Crystal
Keyword(s):  
Dendritic Cells ◽  
Cytotoxic T Lymphocyte ◽  
Tumor Regression ◽  
Ex Vivo ◽  
Tumor Model ◽  
Adenovirus Vector ◽  
Cd40 Ligand ◽  
Murine Tumors

CD40 ligand (CD40L) is essential for the initiation of antigen-specific T-cell responses. This study is based on the hypothesis that dendritic cells (DCs) genetically modified ex vivo to express CD40L will enhance in vivo presentation of tumor antigen to the cellular immune system with consequent induction of antitumor immunity to suppress tumor growth. To examine this concept, subcutaneous murine tumors were injected with bone marrow-derived DCs that had been modified in vitro with an adenovirus (Ad) vector expressing murine CD40L (AdmCD40L). In B16 (H-2b, melanoma) and CT26 (H-2d, colon cancer) murine models, intratumoral injection of 2 × 106 AdmCD40L-modified DCs (CD40L-DCs) to established (day 8) subcutaneous tumors resulted in sustained tumor regression and survival advantage. This antitumor effect was sustained when the number of CD40L-DCs were reduced 10-fold to 2 × 105. Analysis of spleens from CD40L-DC–treated animals demonstrated that CD40L-DCs injected into the subcutaneous CT26 flank tumors migrated to the spleen, resulting in activation of immune-relevant processes. Consistent with this concept, intratumoral administration of CD40L-DCs elicited tumor-specific cytotoxic T-lymphocyte responses, and the transfer of spleen cells from CD40L-DC–treated mice efficiently protected naive mice against a subsequent tumor challenge. In a distant 2-tumor model of metastatic disease, an untreated B16 tumor in the right flank regressed in parallel with a left B16 tumor treated with direct injection of CD40L-DCs. These results support the concept that genetic modification of DCs with a recombinant CD40L adenovirus vector may be a useful strategy for directly activating DCs for cancer immunotherapy.

scholarly journals The injection of deaggregated gamma globulins in adult mice induces antigen-specific unresponsiveness of T helper type 1 but not type 2 lymphocytes.

1992 ◽  
Vol 175 (1) ◽  
pp. 9-14 ◽  
Author(s):  
D De Wit ◽  
M Van Mechelen ◽  
M Ryelandt ◽  
A C Figueiredo ◽  
D Abramowicz ◽  
...  
Keyword(s):  
T Cells ◽  
Tolerance Induction ◽  
T Helper ◽  
Ifn Gamma ◽  
Specific Antibody Response ◽  
Adult Mice ◽  
Helper Type

Injection of adult mice with high doses of monomeric human gamma globulins (dHGG) has been previously shown to produce a state of peripheral tolerance in both B and T cells. To gain insight into the mechanism of induction and maintenance of adult tolerance in this model, we have analyzed the pattern of lymphokines produced by control and tolerant animals in response to the tolerogen. The data presented indicate that HGG-specific, interleukin 2 (IL-2)- and interferon gamma (IFN-gamma)-producing T cells (thus referred to as T helper type 1 [Th1] cells) are rendered unresponsive after in vivo administration of soluble HGG. In contrast, antigenic stimulation of T cells isolated from tolerant adult mice leads to increased production of IL-4 in vitro. In vivo challenge of dHGG-treated adult animals with hapten-coupled HGG (p-azophenylarsonate [ARS]-HGG) induced a significant ARS-specific antibody response, suggesting that tolerance induction in this model does not completely abrogate tolerogen-specific Th activity in vivo. In agreement with the in vitro data, hapten-specific antibody response of tolerant animals is characterized by a selective deficiency in the IFN-gamma-dependent IgG2a subclass. Injection of immunogenic forms of HGG into tolerant animals also produced an IL-4-dependent increase in total serum IgE levels, indicative of an increased activity of HGG-specific Th2 cells in these animals. The finding that tolerance induction differentially affects Th subpopulations suggests that crossregulation among lymphocyte subsets may play a role in the induction and/or maintenance of acquired tolerance in adults.

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