CD8α⁺β⁻ and CD8α⁺β⁺ plasmacytoid dendritic cells induce Foxp3⁺ regulatory T cells and prevent the induction of airway hyper-reactivity

Dendritic cells (DCs) control the balance between protection against pathogens and tolerance to innocuous or self-antigens. Here, we demonstrate for the first time that mouse plasmacytoid DCs (pDCs) can be segregated into three distinct populations, exhibiting phenotypic and functional differences, according to their surface expression of CD8α or CD8β as CD8α⁻β⁻, CD8α⁺β⁻, or CD8α⁺β⁺. In a mouse model of lung inflammation, adoptive transfer of CD8α⁺β⁻ or CD8α⁺β⁺ pDCs prevents the development of airway hyper-reactivity. The tolerogenic features of these subsets are associated with increased production of retinoic acid, which leads to the enhanced induction of Foxp3⁺ regulatory T cells compared with CD8α⁻β⁻ pDCs. Our data thus identify subsets of pDCs with potent tolerogenic functions that may contribute to the maintenance of tolerance in mucosal sites such as the lungs.     

Th17 cells express interleukin-10 receptor and are controlled by Foxp3⁻ and Foxp3+ regulatory CD4+ T cells in an interleukin-10-dependent manner

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Highlights? IL-10 signaling in T cells controls the emergence of Th17 and Th17+Th1 cells ? IL-10Rα is highly expressed by IL-17A-producing CD4⁺ T cells in vivo ? Tr1 and Treg cells can both independently suppress IBD induced by Th17 and Th17+Th1 cells ? Suppression of Th17 and Th17+Th1 cells by Tr1 or Treg cells is dependent on IL-10     

Borrelia burgdorferi infection regulates CD1 expression in human cells and tissues via IL1-β

The appearance of group 1 CD1 proteins (CD1a, CD1b and CD1c) on maturing myeloid DC is a key event that converts myeloid DC to effective lipid APC. Here, we show that Borrelia burgdorferi, the causative agent of Lyme disease, triggers appearance of group 1 CD1 proteins at high density on the surface of human myeloid DC during infection. Within human skin, CD1b and CD1c expression was low or absent prior to infection, but increased significantly after experimental infections and in erythema migrans lesions from Lyme disease patients. The induction of CD1 was initiated by borrelial lipids acting through TLR-2 within minutes, but required 3 days for maximum effect. The delay in CD1 protein appearance involved a multi-step process whereby TLR-2 stimulated cells release soluble factors, which are sufficient to transfer the CD1-inducing effect in trans to other cells. Analysis of these soluble factors identified IL-1β as a previously unknown pathway leading to group 1 CD1 protein function. This study establishes that upregulation of group 1 CD1 proteins is an early event in B. burgdorferi infection and suggests a stepwise mechanism whereby bacterial cell walls, TLR activation and cytokine release cause DC precursors to express group 1 CD1 proteins.     

Concentration levels of IL-10 and TNFα cytokines in patients with human papilloma virus (HPV) DNA⁺ and DNA⁻ cervical lesions

The present study was performed to assess the immune response in women with human papilloma virus (HPV) DNA? and DNA? cervical lesions. Eighty women with cervical lesions (age range?=?25-70 years) and 20 healthy individuals (control group) were enrolled in the study. Lesions were cytologically classified into four groups: ASC-US (20), CINI (30), CINII-III (16), and cervical carcinoma (14) prior to HPV DNA detection. Estimation of interleukin (IL)-10 and tumor necrosis factor (TNF)-α levels in cervical secretions and serum of the studied patients was performed utilizing ELISA. PCR screening kits were used to detect HPV DNA in cervical smears obtained from the studied cases with the different lesions. IL-10 levels in cervical secretions of HPV DNA? were significantly greater than those from DNA? patients (i.e., 88.73 vs 24.00 pg/ml) and from controls (i.e., 88.73 vs 8.27 pg/ml) and the levels were higher in DNA? patients than in controls (i.e., 24.00 vs 8.27 pg/ml). In comparison, serum IL-10 levels in these patients did not significantly differ from control values (i.e., 13.69 vs 12.16 vs 9.99 pg/ml, respectively). TNFα levels in cervical secretions of the HPV DNA? and DNA? cases did not significantly differ from values for the controls (i.e., 12.18 vs 9.90 vs 7.90 pg/ml, respectively). Serum TNFα of these patients also did not differ significantly from controls (i.e., 11.59 vs 11.90 vs 10.83 pg/ml, respectively). The detected levels of IL-10 in cervical secretions of patients with HPV DNA? lesions was significantly higher than in their sera, while secretion TNFα levels were nominally greater than sera values. Lastly, higher levels of IL-10 were observed in secretions of 10-14 (71.4%) patients who had progressive cervical lesions (HSIL and cervical cancer stages) who were HPV DNA? than observed in 20 of 66 (30.0%) of DNA? patients with similar progressive lesions. In general, the higher levels of IL-10 than of TNFα suggested a potential down-modulation of tumor-specific immune responses to HPV-infected lesions. This phenomenon appears to provide a tumor 'progressive' microenvironment in these particular patients.     

Detection and characterization of OX40 ligand expression in human airway smooth muscle cells: a possible role in asthma?

BACKGROUND: The airway smooth muscle (ASM) cell, originally thought of as a passive structural cell, is now well recognized as an active participant in the pathologic events that occur during persistent asthma. Cell-surface molecules play an important role in the development of an immune response. A number of cell-surface molecules are expressed on ASM cells, and these might contribute to the inflammatory reaction. OBJECTIVE: The purpose of this study was to determine whether OX40 ligand (OX40L), a molecule known to be involved in T-cell activation, was present on the ASM cell surface. METHODS: We used real-time RT-PCR to detect mRNA expression and flow cytometry, ELISA, and immunoprecipitation to detect the presence of cell-surface protein on ASM cells isolated from asthmatic and nonasthmatic individuals. ELISAs and Western blotting were used to determine the functional outcomes of engagement of OX40L. RESULTS: OX40L was present on both asthmatic and nonasthmatic ASM cells. Engagement of OX40L with recombinant OX40:Fc resulted in a significantly greater increase in release of IL-6 from ASM cells of asthmatic patients than from ASM cells of nonasthmatic patients (P<.01). Ligation of OX40L resulted in a rapid translocation of protein kinase C beta2 to the cell membrane. Conclusion: Because the receptor for OX40L, OX40, is expressed on CD4+ T cells within 48 hours of stimulation through the T-cell receptor, elucidation of the cross-talk between OX40 and OX40L could be very important in understanding the interaction of cells present in the inflamed airways of an asthmatic patient.     

CD8 T cells expressing killer Ig-like receptors and NKG2A are present in cord blood and express a more naïve phenotype than their counterparts in adult blood

We report that natural killer receptors (NKR) for major histocompatibility complex (MHC) class I molecules (MHC-NKR), the inhibitory killer immunoglobulin-like receptors (KIR), and the CD94/NKG2A receptor are present on a small proportion of CD8 T cells in cord blood. On average, 1.67% of CD8 T cells in cord blood express KIR, and 0.74% expresses NKG2A, approximately fivefold less than in adult blood. CD8 T cells expressing MHC-NKR were present at similar levels in cord blood from preterm and term infants, and it is important that their presence was independent of placental pathology or infection. Cord blood CD8 T cells expressing MHC-NKR were relatively homogeneous and entirely CD27+, mostly CC chemokine receptor 7- and granzyme B-, with a majority being CD45RA+ and with no evidence for a skewed distribution of T cell receptor-Vbeta when tested in KIR+ cells. This contrasted with adult blood, which was more heterogeneous, and where a majority of CD8 T cells expressing MHC-NKR was CD27- and granzyme B+. Functional studies revealed that cord blood KIR+ CD8 T cells were as capable as KIR- CD8 T cells in their ability to proliferate in response to CD3 ligation, yet it is interesting that they were more capable than KIR- CD8 T cells in their ability to secrete interferon-gamma. These data suggest that cord blood CD8 T cells expressing MHC-NKR are a unique subset of cells, distinct from those in adult blood, and may represent a less-differentiated population.     

Intracellular production of IL-2, IL-4 and IFN-γ by peripheral blood CD3+ cells in intermittent allergic rhinitis

Background: Allergic inflammation is mainly driven by type 2 T helper cells. The aim was to assess the changes in production of type 1 and 2 cytokines by CD3⁺ T cells dependent on natural exposure to allergens in subjects with intermittent allergic rhinitis (IAR) and in non-atopic subjects.Material: A total of 13 patients with IAR and 13 healthy non-atopics were recruited into the study. 11 patients with IAR were examined during the grass pollen season and 11 patients outside the season, 9 of them were assessed on both occasions.Methods: A flow cytometric assessment of intracellular expression of IL-2, IL-4 and IFN- by CD3⁺ cells was performed. For statistical analysis non-parametric tests were used.Results: A tendency to decreased production of IL-4 outside the season was observed (6.94% [3.42–13.33] in season vs. 2.06% [0.7–3.6] out of season). The production of IL-4 was higher in the rhinitic group in the season than in the control group (1.93% [1.07–4.97], p = 0.0034) and production of IL-2 was higher both in and outside the season (9.1% [3.94–15.09] and 10.0% [4.79–25.35] vs. 3.64% (2.64–5.03), p = 0.037 and 0.045, respectively). IL-4/IL-2 and IL-4/IFN- ratios were higher in the IAR group in the season than outside the season.Conclusion: A tendency towards a switch from a predominant type 2 response during natural allergen exposure to its suppression outside the season was found, together with a stable type 1 response.Received 22 July 2004; returned for revision 27 August 2004; accepted by M. J. Parnham 2 November 2004     

A major population of mucosal memory CD4+ T cells,coexpressing IL-18Rα and DR3, display innate lymphocyte functionality

Mucosal tissues contain large numbers of memory CD4⁺ T cells that, through T-cell receptor-dependent interactions with antigen-presenting cells, are believed to have a key role in barrier defense and maintenance of tissue integrity. Here we identify a major subset of memory CD4⁺ T cells at barrier surfaces that coexpress interleukin-18 receptor alpha (IL-18Rα) and death receptor-3 (DR3), and display innate lymphocyte functionality. The cytokines IL-15 or the DR3 ligand tumor necrosis factor (TNF)-like cytokine 1A (TL1a) induced memory IL-18Rα⁺DR3⁺CD4⁺ T cells to produce interferon-γ, TNF-α, IL-6, IL-5, IL-13, granulocyte–macrophage colony-stimulating factor (GM-CSF), and IL-22 in the presence of IL-12/IL-18. TL1a synergized with IL-15 to enhance this response, while suppressing IL-15-induced IL-10 production. TL1a- and IL-15-mediated cytokine induction required the presence of IL-18, whereas induction of IL-5, IL-13, GM-CSF, and IL-22 was IL-12 independent. IL-18Rα⁺DR3⁺CD4⁺ T cells with similar functionality were present in human skin, nasal polyps, and, in particular, the intestine, where in chronic inflammation they localized with IL-18-producing cells in lymphoid aggregates. Collectively, these results suggest that human memory IL-18Rα⁺DR3⁺ CD4⁺ T cells may contribute to antigen-independent innate responses at barrier surfaces.     

Interleukin-3 stabilizes CD124/IL-4α surface expression in mast cells via Tyk2 and STAT6

Interleukin (IL)-4 signals can modulate mast cells, which express the IL-4Rα chain. The IL-4Rα can heterodimerise with the common γ-chain and utilizes JAK1 and JAK2 for signal transduction, while complexes of IL-4Rα with IL-13Rα1 subunit mediates signals via JAK2 and Tyk2. Here, we report that IL-3 is an essential factor for the continuous expression of the IL-4Rα chain on mast cells, which did not express the IL-13Rα1 chain. We demonstrate that the signals induced by IL-3 important for IL-4Rα expression are mediated by Tyk2 and STAT6 activation and the subsequent maintenance of HSP90 levels. In line with that, inhibition of either Tyk2, STAT6 or HSP90 impaired the IL-3-induced IL-4Rα upregulation. Consequently, the IL-3 maintained IL-4Rα surface expression via Tyk2 is essential for the costimulatory effect of IL-4 on the IL-33-induced production of IL-6 and IL-13.     

In vitro expansion of human γδ and CD56(+) T-cells by Aspergillus-antigen loaded fast dendritic cells in the presence of exogenous interleukin-12

Aspergillus fumigatus (Af) infection is especially prevalent after allogenic bone marrow transplantation (BMT) and causes invasive pulmonary aspergillosis. Human γδ T-cells have essential role in maintaining immune homeostasis and in the resistance of pathogens and tumors. Also, γδ T-cells may facilitate stem cells engraftment and decrease a life-threatening graft versus host disease after allogenic BMT. Moreover, expression of CD56 molecules on γδ T-cells increases their antitumor cytotoxic activity. This study reveals that Af-pulsed fast dendritic cells (fast-DCs, which generated within only 72?h) plus IL-12 and then IL-2 can propagate autologous γδ and CD56(+) T-cells in vitro and this expansion is sustained by repeating the stimulation (107.5?±?13.9-fold and 37.6?±?2.2-fold increase for γδ and CD56(+) T-cells, respectively, after three primings). Many of the expanded γδ and CD56(+) T-cells expressed CD8 molecules (29.6%-68.6%), while few of them expressed CD4 molecules (2.3%-17.5%). Also, ～28% of the expanded γδ T-cells were CD56(+). On the other hand, the proliferation of γδ and CD56(+) T-cells significantly decreased (p?相似文献   

Differential expression of GSK3β and pS9GSK3β in normal human tissues: can pS9GSK3β be an epithelial marker?

Glycogen synthase kinase 3β (GSK3β) and phosphorylated GSK3β at Ser9 (pS9GSK3β) are crucial in cellular proliferation and metabolism. GSK3β and pS9GSK3β are deregulated in many diseases including tumors. Data on altered expression of GSK3β and pS9GSK3β are mainly limited to tumor tissues, thus the expression of GSK3β and pS9GSK3β in normal human tissue has been largely unknown. Thus, we examined the immunohistochemical localization of GSK3β and pS9GSK3β in human fetal and adult tissues, and also compared the expression pattern of GSK3β and pS9GSK3β with that of the CK7 and CK20. We found GSK3β expression in neurons of brain, myenteric plexus in gastrointestinal tract, squamous epithelium of skin, and mammary gland. The expression of pS9GSK3β was restricted to the epithelial cells of breast and pancreaticobiliary duct, distal nephron of kidney, gastrointestinal tract, fallopian tube, epididymis, secretory cell of prostatic gland, and umbrella cell of urinary tract. The staining pattern of pS9GSK3β and CK7 was overlapped in most organs except for gastrointestinal tract where CK7 was negative and CK20 was positive. Our results show that the expression of GSK3β may be associated with differentiation of ectodermal derived tissues and pS9GSK3β with that of epithelial cells of endodermal derived tissues in human. In addition, the expression of pS9GSK3β in the selective epithelial cells may indicate its association with secretory or barrier function of specific cells and may serve as another immunohistochemical marker for epithelial cells.     

IL-22 promotes Fas expression in oligodendrocytes and inhibits FOXP3 expression in T cells by activating the NF-κB pathway in multiple sclerosis

Multiple sclerosis (MS) is characterized by an increase in interleukin-22 and Fas, and a decrease in FOXP3, among other factors. In this study, we examined patients with MS and healthy control subjects and used the experimental autoimmune encephalomyelitis (EAE) animal model to identify the effects of IL-22 on oligodendrocytes and T cells in MS development. In MS, the expression of Fas in oligodendrocytes and IL-22 in CD4⁺CCR4⁺CCR6⁺CCR10⁺ T cells was enhanced. Ikaros and FOXP3 were both decreased in T cells. Depending on exogenous IL-22, Fas increased the phosphorylation of mitogen- and stress-activated protein kinase 1 and activated the nuclear factor-κB pathway in oligodendrocytes, leading to an increase in Fas and oligodendrocyte apoptosis. IL-22 decreased FOXP3 expression by activating NF-κB, and it further inhibited PTEN and Ikaros expression. Tregs reversed the functions of IL-22. Taken together, these findings help to elucidate the mechanisms of IL-22 in MS development.     

PKCδ regulates IL-12p40/p70 production by macrophages and dendritic cells, driving a type 1 healer phenotype in cutaneous leishmaniasis

The protein kinase C (PKC) family is involved in the regulation of many intracellular signalling pathways. Here, we report that the PKCδ isoform regulates IL-12p40/p70 production in macrophages and DC and that PKCδ deficiency in mice transforms the 129/Sv healer to a non-healer strain during cutaneous leishmaniasis. Leishmania major-infected PKCδ(-/-) 129/Sv mice developed a rapid increase in footpad swelling and parasite burden with disease progression, leading to necrosis and ulceration similar to non-healer BALB/c mice. Moreover, PKCδ(-/-) mice failed to develop delayed-type hypersensitivity responses against Leishmania antigen. PKCδ(-/-) macrophages were fully functional with normal MHC class II surface expression and GM-CSF production, recruitment to the draining lymph node and killing effector functions by NO production. In contrast, macrophages and DC produced significantly reduced IL-12p40 and IL-12p70 compared to the WT cells. Decreased IL-12 production resulted in diminished Th1 differentiation, as determined by a striking reduction in IFN-γ by antigen-specific stimulated CD4(+) T cells isolated from popliteal lymph nodes of L. major-infected PKCδ(-/-) mice, explaining the "non-healer" phenotype. We conclude from these data that PKCδ is a regulator of IL-12p40/p70 production by DC and macrophages, driving the healer phenotype during cutaneous leishmaniasis.     

Production and expression of RANTES (CCL5) by human disc cells and modulation by IL-1-β and TNF-α in 3D culture

Chemokines act as important secondary inflammatory mediators which are released by cells in response to a variety of stimuli. Chemokines bind to cell surface receptors and act as second-order cytokines with specialized functions in inflammation. The role of RANTES (Regulated upon Activation, Normal T-cell Expressed, and Secreted) (also called CCL5 (chemokine (C–C motif) ligand 5)) has received little attention to date in disc tissue. Microarray analyses of lumbar disc annulus tissue revealed that RANTES expression was significantly upregulated in more degenerated Thompson grades IV and V discs compared to expression levels in grades I, II and III discs (p = 0.032). Immunolocalization confirmed the presence of RANTES in the annulus and nucleus of the disc, and localized the RANTES receptors CCR1, CCR3 and CCR5 to cells in the disc. In vitro studies with IL-1-β and TNF-α challenges, both proinflammatory cytokines resulted in elevated levels of RANTES in conditioned media (p < 0.01); TNF-α exposure, however, produced significantly greater levels than did IL-1alpha (p < 0.0001), suggesting a differential regulation by TNF-α. Local production of RANTES in vivo by annulus and nucleus cells, and in vitro induction of RANTES by proinflammatory cytokines suggest that disc cells are primary effector cells as well as target cells, and thus can mediate physiological immune-related processes during disc degeneration by both autocrine and paracrine signaling.     

Regulatory B cells from hilar lymph nodes of tolerant mice in a murine model of allergic airway disease are CD5+, express TGF-β, and co-localize with CD4+Foxp3+ T cells

In a biphasic, ovalbumin (OVA)-induced murine asthma model where allergic airway disease is followed by resolution and the development of local inhalational tolerance (LIT), transforming growth factor (TGF)-β-expressing CD5⁺ B cells were selectively expanded locally in hilar lymph nodes (HLN) of LIT mice. LIT HLN CD5⁺ B cells, but not LIT HLN CD5^– B cells, induced expression of Foxp3 in CD4⁺CD25^– T cells in vitro. These CD5⁺ regulatory B cells (Breg) and CD4⁺Foxp3⁺ T cells demonstrated similar increases in expression of chemokine receptors (CXCR4 and CXCR5) and co-localized in HLN B cell zones of LIT mice. The adoptive transfer of LIT HLN CD5⁺ B cells, but not LIT HLN CD5^– B cells, increased the number of CD4⁺Foxp3⁺ T cells in the lung and inhibited airway eosinophilia in this OVA model. Thus, Breg in HLNs of LIT mice reside in a CD5⁺ TGF-β-producing subpopulation and co-localize with CD4⁺Foxp3⁺ T cells.