bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics of GATA‐3 gene expression in early polarizing and committed human T cells
Authors: Lantelme E. , Mantovani S. , Palermo B. , Campanelli R. , Sallusto F. , Giachino C. 
Published: March 2003

SummaryDifferent transcription factors have been shown to control the transition of naive T cells into T helper 1 (Th1)/Th2 subsets. The T‐cell‐specific transcription factor GATA‐3 is known to be selectively expressed in murine developing Th2 cells and to exert a positive action on Th2‐specific cytokine production. Investigating GATA‐3 gene regulation in human T cells we have found that naive T cells highly express GATA‐3, and during early T2 or T1 polarization, respectively, they either maintain or quickly down‐regulate expression. In developing T2 cells, as well as in committed Th2 cell lines and clones, we found a positive correlation among GATA‐3, interleukin (IL)‐5 and IL‐4 gene expression kinetics, supporting the positive action of GATA‐3 on Th2‐specific cytokine production. A possible relationship between GATA‐3 gene expression and the down‐regulation of the IL‐12 receptor (β2‐chain; IL‐12Rβ2) gene was evident only in the early phases of T2 polarization (within 24 hr), and not demonstrated at later times. During T‐cell commitment the presence of IL‐4 in the culture was essential to maintain or enhance GATA‐3 transcription, while IL‐12 was not necessary for full repression of GATA‐3. Finally, we showed selective GATA‐3 up‐regulation in human Th2 cell lines and clones and the maintainance of a low basal level of GATA‐3 expression in Th1 cells upon activation.
Detection of anaphylatoxin receptors on CD83+ dendritic cells derived from human skin
Authors: Kirchhoff Konstanze , Weinmann Oliver , Zwirner Jörg , Begemann Gabriele , Götze Otto , Kapp Alexander , Werfel Thomas 
Published: March 2003

SummaryDendritic cells (DC) are recruited to sites of inflammation for the initiation of immune responses. As the anaphylatoxins C5a and C3a are important mediators of inflammation, we investigated the expression of their receptors (C3aR and C5aR) on human DC. DC were isolated from human skin or generated from purified blood monocytes and were identified by their expression of CD1a or CD83. Freshly isolated or cultured dermal CD1a+ and CD83+ DC bound anti‐C5aR and anti‐C3aR monoclonal antibodies (mAbs), as detected by flow cytometry. C5a induced calcium fluxes in dermal CD1a+ and CD83+ DC, which could be inhibited by C17/5, an anti‐C5a mAb. C3a did not induce calcium fluxes in these cells. Anaphylatoxin receptor expression was down‐regulated on dermal DC by adding tumour necrosis factor‐α (TNF‐α) to the culture medium. On CD1a+ CD83− cells generated from isolated blood monocytes by culture with 6·25 ng/ml of granulocyte–macrophage colony‐stimulating factor (GM‐CSF) and 125 U/ml of interleukin‐4 (IL‐4), expression of both C5aR and C3aR was observed. In these cells, both C5a and C3a induced calcium fluxes. After addition of TNF‐α to the culture medium, the majority of the CD1a+ cells expressed CD83+. These cells – expressing a phenotype of ‘mature DC’– down‐regulated the expression of the anaphylatoxin receptors and lost their reactivity to the respective ligands. Our results demonstrate the expression of the anaphylatoxin receptors C5aR and C3aR on human skin‐derived DC and blood‐derived cells expressing the DC‐associated membrane molecule, CD1a. Furthermore, the expression of anaphylatoxin receptors on CD83+ dermal DC is indicative of an intermediate stage of maturation of these cells, which was not observed on in vitro‐differentiated CD83+ cells.
Immunostimulation by the synthetic lipopeptide P3CSK4: TLR4‐independent activation of the ERK1/2 signal transduction pathway in macrophages
Authors: Müller Markus R. , Pfannes Silke D. C. , Ayoub Mohamed , Hoffmann Petra , Bessler Wolfgang G. , Mittenbühler Klaus 
Published: March 2003

SummarySynthetic lipopeptides based on bacterial lipoprotein are efficient activators for monocytes/macrophages inducing the release of interleukin (IL)‐1, IL‐6, tumour necrosis factor‐α (TNF‐α), reactive oxygen/nitrogen intermediates, and the translocation of nuclear factor κB (NFκB). In this report we investigate the signal transduction pathways involved in leucocyte activation by the synthetic lipopeptide N‐palmitoyl‐S‐[2,3‐bis(palmitoyloxy)‐(2R,S)‐propyl]‐(R)‐cysteinyl‐seryl‐(lysyl)3‐lysine (P3CSK4). We show that P3CSK4 activates mitogen‐activated protein (MAP)‐kinases ERK1/2 and MAP kinase (MAPK)‐kinases MEK1/2 in bone‐marrow‐derived macrophages (BMDM) and in the macrophage cell line RAW 264·7. Additionally, we could detect differences between the P3CSK4 and lipopolysaccharide (LPS)‐induced phosphorylation of MAP kinases: Different levels in phosphorylation were found both in kinetics and dose–response using RAW 264·7 cells or BMDM from BALB/c and LPS responder mice (C57BL/10ScSn) or LPS non‐responder mice (C57BL/10ScCr). The lipopeptide activated the MAPK‐signalling cascade in both LPS responder and non‐responder macrophages, whereas LPS induced the MAPK signalling pathway only in macrophages derived from LPS responder mice. An approximately 70% decrease of lipopeptide induced NFκB translocation and an about 50% reduction of nitric oxide (NO) release was observed in the presence of anti‐CD14. These data correspond to the reduction of phosphorylation of ERK1/2 after stimulation with P3CSK4 in the presence of anti‐CD14 antibodies. Inhibition of MEK1/2 by PD98059 completely reduced the lipopeptide‐induced phosphorylation of ERK1/2 indicating that MEK1/2 are solely responsible for the phosphorylation of the downstream‐located MAP kinases ERK1/2.
Intensive generation of NK1.1– extrathymic T cells in the liver by injection of bone marrow cells isolated from mice with a mutation of polymorphic major histocompatibility complex antigens
Authors: Halder R. C. , Kawamura T. , Bannai M. , Watanabe H. , Kawamura H. , Mannoor M. K. , Morshed S. R. M. , Abo T. 
Published: March 2003

SummaryWhether intermediate TCR (TCRint) cells and natural killer T (NKT or NK1.1+TCRint) cells are extrathymically generated remains controversial. This arises from the fact that there are few of these T cells in athymic nude mice and neonatally thymectomized mice. However, when athymic mice were provided with appropriate microenvironments or stimulation, many TCRint cells (mainly NK1.1−) were found to arise in the liver. NKT cells are known to be positively selected by monomorphic major histocompatibility complex (MHC) ‐like antigens (e.g. CD1d). This is true even if they are CD4+. In other words, a MHC class I‐like antigen is restricted to CD4 antigen. This rule is somewhat different from that seen in conventional T cells (i.e. the restriction of class II with CD4 and that of class I and CD8). In the case of NK1.1−TCRint cells, they were selected by polymorphic MHC antigens, but their MHC restriction to CD4 or CD8 antigen was incomplete. This was revealed by experiments of bone marrow transfer with class I (bm 1) or II (bm 12) disparity. Depending on the disparity, a unique cytokine profile in sera was detected. These results suggest that the development of T lineage lymphocytes and MHC restriction to CD4 and CD8 might have occurred in parallell as a phylogenic event, and that NK1.1− extrathymic T cells (i.e. NK1.1−TCRint) are at an intermediate position between NKT cells and conventional T cells in phylogeny.
Immunoglobulin VH‐gene usage of autoantibodies in mercuric chloride‐induced membranous glomerulopathy in the rat
Authors: Dammers Peter M. , Bun Judy C. A. M. , Bellon Blanche , Kroese Frans G. M. , Aten Jan , Bos Nicolaas A. 
Published: March 2003

SummaryBrown‐Norway (BN) and Dorus Zadel Black (DZB) rats develop a T‐cell‐dependent membranous glomerulopathy (MGP) with high proteinuria and antiglomerular basement membrane (GBM) autoreactive antibodies (Abs), upon exposure to mercuric chloride (HgCl2). Laminin is an important autoantigenic target of the anti‐GBM Abs, absorbing ≈ 30% of the anti‐GBM reactivity. Although many anti‐GBM Abs have undergone isotype switching, it is currently unclear whether affinity maturation occurs during the HgCl2‐induced autoimmune response. To address this question we analysed the rearranged immunoglobulin heavy chain variable‐region genes (VHDJH regions) of 15 mAbs that were previously obtained from HgCl2‐treated rats. Seven of these mAbs exhibit reactivity towards laminin. Our study showed that the VH‐gene usage of antilaminin mAbs is largely restricted to the PC7183 VH‐gene family (six out of seven). In addition, we demonstrated that at least three out of six laminin reactive and five out of six non‐laminin‐binding mAbs are encoded by germline VH genes (a total of eight out of 12 mAbs). Of the eight mAbs that are encoded by germline VH genes, seven are of a non‐immunoglobulin M (IgM) isotype, indicating that isotype switching has occurred in these mAbs in the absence of somatic mutations. The mutations observed in the VH genes of the four remaining mAbs do not provide strong evidence for antigenic selection. The data support the notion that B cells in this model of MGP are not subjected to affinity maturation and probably result from polyclonal B‐cell activation.
Specific immunoglobulin E responses in ZAP‐70‐deficient patients are mediated by Syk‐dependent T‐cell receptor signalling
Authors: Toyabe Shin‐ichi , Watanabe Akihiro , Harada Waka , Karasawa Tamaki , Uchiyama Makoto 
Published: March 2003

SummaryZAP‐70 deficiency is a rare primary immunodeficiency characterized by the absence of peripheral CD8+ T cells and defects in T‐cell receptor (TCR) signalling. T cells in ZAP‐70‐deficient patients are assumed to have no helper functions for B‐cell immunoglobulin synthesis, whereas the patients rarely have antigen‐specific antibodies. We experienced a ZAP‐70‐deficient patient, who had immunoglobulin E (IgE) antibodies specific to food allergens, and we investigated the mechanisms of switching to IgE in the patient. Peripheral blood mononuclear cells from the patient did not proliferate upon stimulation with the antigens but produced distinct levels of interleukin‐4 (IL‐4). Cell sorting analysis indicated that the cells that produced IL‐4 in response to the antigens were enriched in CD4+ T cells. Purified CD4+ T cells from the patient produced IL‐4 and expressed CD40L upon stimulation with anti‐CD3. Moreover, CD4+ T cells pretreated with anti‐CD3 induced mature ε transcript on naive B cells. Since the results indicated that there remained sufficient T‐cell receptor (TCR)‐signalling in the patient's T cells to exert antigen‐specific IgE switching on B cells, we next investigated the expression of the ZAP‐70‐homologous kinase Syk. Syk was present in high levels in patient's CD4+ T cells and was tyrosine‐phosphorylated after TCR stimulation. Inhibition of Syk by piceatannol resulted in decreased production of IL‐4 and expression of CD40L on patient's CD4+ T cells. Moreover, Syk was expressed on all human T‐cell leukaemia virus (HTLV‐1)‐transformed T‐cell lines derived from peripheral blood of the patient, whereas it was low or undetectable in control lines. It was therefore concluded that specific IgE responses in the patient were most likely to be mediated by Syk‐dependent TCR‐signalling.
Tumour necrosis factor‐α potentiates CR3‐induced respiratory burst by activating p38 MAP kinase in human neutrophils
Authors: Forsberg Maria , Löfgren Ragnhild , Zheng Limin , Stendahl Olle 
Published: March 2003

SummaryCR3 and FcγRs are the main receptors involved in the phagocytic process leading to engulfment and killing of microbes by production of reactive oxygen intermediates (ROI) and degranulation. Various inflammatory mediators, such as tumour necrosis factor‐α (TNF‐α) and lipopolysaccharide (LPS), are known to prime neutrophils leading to increased bactericidal responses, but the underlying mechanism of priming has only been partially elucidated. The purpose of this study was to investigate how TNF‐α primes neutrophils for subsequent stimuli via either CR3 or FcγR. The receptors were specifically activated with pansorbins (protein‐A‐positive Staphylococcus aureus) coated with anti‐CR3, anti‐FcγRIIa, or anti‐FcγRIIIb monoclonal antibody. Activation of neutrophils with these particles resulted in ROI production as measured by chemiluminescence. Anti‐CR3 pansorbins induced the most prominent ROI production in neutrophils. TNF‐α potentiated the CR3‐mediated respiratory burst but had little effect on that mediated by FcγRs. The priming effect of TNF‐α on CR3‐mediated ROI production is associated with an increased activation of p38 MAPK as well as tyrosine phosphorylation of p72syk. Pretreatment of neutrophils with the inhibitors for p38 MAPK and p72syk markedly suppressed the respiratory burst induced by CR3. Furthermore, TNF‐α induced about a three‐fold increase in the expression of CR3 in neutrophils, an effect which is blocked by the p38 MAPK inhibitor. Taken together, these results showed that TNF‐α potentiates the CR3‐mediated respiratory burst in neutrophils not only by triggering a p38 MAPK‐dependent up‐regulation of CD11b/CD18 but also by modulating the signalling pathways.
Topical tacrolimus and cyclosporin A differentially inhibit early and late effector phases of cutaneous delayed‐type and immunoglobulin E hypersensitivity
Authors: Geba Gregory P. , Ptak Wlodzimierz , Askenase Philip W. 
Published: March 2003

SummarySystemic and topical administration routes of tacrolimus and cyclosporin A (CsA) were compared in effects on early and late phases of elicited T‐cell‐mediated contact sensitivity (CS), and effects on early and late phases of cutaneous immunoglobulin E (IgE) antibody‐mediated hypersensitivity responses in mice. Thus, both CS and IgE responses in the skin have an early mast‐cell‐dependent phase, and also a late inflammatory phase. We measured the effects of both immunosuppressants on both phases of the respective T cell versus IgE responses. Systemic administration of both agents completely suppressed CS and IgE late‐phase responses, but failed to affect either early phase. In contrast, when topical CsA was used, low doses abolished the early phase of IgE responses, but even high doses did not inhibit the early phase of CS. Conversely, topical tacrolimus inhibited the early phase of CS more potently than the early phase of cutaneous IgE hypersensitivity responses. Thus, topical treatment was needed to inhibit the early phases and the two agents acted differentially, suggesting differing susceptibility of the early phases, that are probably due to different signalling mechanisms. These studies underscore the potential value of topical administration of these powerful immunosuppressive agents in the treatment of allergic diseases that exhibit features of early‐phase mast‐cell‐dependent inflammation, and late inflammation due to mast cells or to T cells, such as atopic dermatitis or asthma, since the early phase is predominantly susceptible to topical application, while the last phase of both IgE and T‐cell inflammation responds to systemic treatment with both agents.
Granule‐dependent killing of Toxoplasma gondii by CD8+ T cells
Authors: Nakano Yoko , Hisaeda Hajime , Sakai Tohru , Zhang Manxin , Maekawa Yoichi , Zhang Tianqian , Nishitani Masaaki , Ishikawa Hiroyuki , Himeno Kunisuke 
Published: March 2003

SummaryImmunization of mice with live bradyzoites of a low‐virulent Beverley strain of Toxoplasma gondii has been shown to increase CD8+ T‐cell mediated immunity against a highly virulent RH strain. We found that preimmunization with an RH homogenate further enhanced this immunity. Using this model, we investigated the mechanism of CD8+ T‐cell mediated protection against T. gondii infection. Splenic cells from mice immunized with RH homogenate and live bradyzoites stimulated apoptosis of RH‐infected J774A.1 macrophages in vitro, and at the same time, the immunization significantly suppressed the proliferation of parasites within macrophages, as assessed by measuring 3H‐uracil uptake by the parasites. Splenic cells from the immunized mice produced larger amounts of interferon‐γ (IFN‐γ) than did naive splenic cells; however, the production of nitric oxide (NO) by RH‐infected macrophages was not enhanced. The elimination of CD8+ T cells from splenic cells significantly reduced their inhibitory action on parasite proliferation as well as their cytotoxic activity against RH‐infected macrophages, but it did not affect the production of IFN‐γ. Treatment of CD8+ T‐enriched splenic cells from the immunized mice with concanamycin A, but not an anti‐Fas ligand monoclonal antibody, significantly reduced their anti‐proliferative and killing capabilities, suggesting that the CD8+ T cells induced by immunization with RH antigen and live bradyzoites of the Beverley strain may exert protection against T. gondii infection at least in part through granule‐dependent cytotoxic activities.
T‐cell activation, proliferation and apoptosis in primary Listeria monocytogenes infection
Authors: Mannering Stuart I. , Zhong Jie , Cheers Christina 
Published: March 2003

Summary Listeria monocytogenes infection of mice leads to a rapid expansion of activated T cells, followed by a decline in specific cells once the bacteria are eliminated. In order to define the relationship between T‐cell proliferation and activation, and to investigate the role of apoptosis in limiting the expansion, the expression of activation markers, uptake of 5‐bromo‐2′‐deoxyuridine (BrdU) in vivo and the incidence of apoptosis was investigated. Increased numbers of T cells expressing the activated phenotype CD25+, CD44hi and CD62Llo were detected 4 days after infection. Expression of CD25 (IL‐2Rα chain) on CD4+ and CD8+ T cells peaked at this time and returned to normal by day 7. In contrast, CD44hi and CD62Llo persisted, with the maximum proportion occurring at 7 days after infection. This was accompanied by a burst of in vivo proliferation of CD4+ and CD8+ T cells occurring between day 5 and 7. Apoptosis, which is presumably needed to control this expansion of T cells, also peaked at 7 days after infection. Apoptosis occurred preferentially amongst T cells which had proliferated. Most but not all proliferating T cells had down‐regulated their CD62L marker. While most apoptotic T cells were CD62Llo, again not all had down‐regulated this marker. Hence, CD25 expression peaked early, but expression of other activation markers, in vivo proliferation and apoptosis coincided after Listeria infection. T cells that had proliferated were over‐represented in the apoptotic population.
Characterizing a soluble survival signal for activated lymphocytes from CD14+ cells
Authors: Tang Xiaolei , Yocum David E. , DeJonghe David , Nordensson Kathy 
Published: March 2003

SummaryT‐cell activation requires at least two signals: antigen and a costimulatory signal. As antigen‐presenting cells play an important role in this area, the role of CD14+ cells in T‐cell activation, proliferation and activation‐induced cell death (AICD) was investigated. Using phytohaemagglutinin (PHA) activation, it was found that CD14+ cell depletion resulted in significantly greater AICD, decreased lymphocyte growth and up‐regulated interleukin‐2 (IL‐2) secretion. However, T‐cell activation was delayed according to the expression of CD69 and CD25. Dynabeads conjugated with anti‐CD14 monoclonal antibody (mAb) bound CD14+ cells and induced secretion of IL‐1β, tumour necrosis factor‐α (TNF‐α), transforming growth factor‐β (TGF‐β) and IL‐6, but not IL‐2, IL‐12 or IL‐15. Supernatants were collected from Dynabeads‐activated CD14+ cell cultures and designated as ‘CD14 cocktails’. Addition of CD14 cocktails to CD14+ cell‐depleted mononuclear cell cultures reversed the increased AICD, decreased lymphocyte growth and increased IL‐2 secretion. Depletion of IL‐1β and TNF‐α in the CD14 cocktails by panning followed by blocking with the corresponding mAbs had no effect on the active AICD protection. TGF‐β was determined not to be the active factor owing to the presence of >1·0 ng of TGF‐β in the media for culturing both CD14+ and CD14− peripheral blood mononuclear cells (PBMC). The CD14 cocktails did not contain IL‐12 and IL‐15. Depletion of IL‐6 with panning followed by blocking residual IL‐6 with anti‐IL‐6 mAb significantly reduced the protective effect of the CD14 cocktails. Human recombinant IL‐6 also partially reversed the effects of CD14+ cell depletion on AICD, lymphocyte growth and IL‐2 secretion. The data suggest that IL‐6 is one of the active factors in the survival signal from CD14+ cells.
Regulation of adhesion of AML14.3D10 cells by surface clustering of β2‐integrin caused by ERK‐independent activation of cPLA2
Authors: Myou Shigeharu , Zhu Xiangdong , Boetticher Evan , Qin Yimin , Myo Saori , Meliton Angelo , Lambertino Anissa , Munoz Nilda M. , Hamann Kimm J. , Leff Alan R. 
Published: March 2003

SummaryWe examined the role of cell surface clustering of β2‐integrin caused by protein kinase C (PKC)‐activated‐cPLA2 in adhesion of eosinophilic AML14.3D10 (AML) cells. Phorbol 12‐myristate 13‐acetate (PMA) caused time‐ and concentration‐dependent adhesion of AML cells to plated bovine serum albumin (BSA), which was blocked by anti‐CD11b or anti‐CD18 monoclonal antibodies (mAb) directed against β2‐integrin. Inhibition of PKC with Ro‐31‐8220 or rottlerin blocked PMA‐induced cell adhesion in a concentration‐dependent fashion. Inhibition of cytosolic phospholipase A2 (cPLA2) with trifluoromethyl ketone or methyl arachidonyl fluorophosphonate also blocked PMA‐induced cell adhesion. PMA caused time‐dependent p42/44 mitogen‐activated protein kinase (MAPK) (ERK) phosphorylation in these cells. U0126, a MAPK/extracellular signal‐regulated protein kinase kinase (MEK) inhibitor, at the concentrations that blocked PMA‐induced ERK phosphorylation, had no effect on PMA stimulated AML cell adhesion. Neither p38 MAPK nor c‐Jun N‐terminal kinase (JNK) was phosphorylated by PMA. PMA also caused increased cPLA2 activity, which was inhibited by Ro‐31‐8220, but not U0126. Confocal immunofluorescence microscopy showed that PMA caused clustering of CD11b on the cell surface, which was blocked by either PKC or cPLA2 inhibition. PMA stimulation also caused up‐regulation of CD11b on the AML cell surface. However, this up‐regulation was not affected by cPLA2‐ or PKC‐inhibition. Using the mAb, CBRM1/5, we also demonstrated that PMA does not induce the active conformation of CD11b/CD18. Our data indicate that PMA causes AML cell adhesion through β2‐integrin by PKC activation of cPLA2. This pathway is independent of MEK/ERK and does not require change of CD11b/CD18 to its active conformation. We find that avidity caused by integrin surface clustering – rather than conformational change or up‐regulation of CD11b/CD18 – causes PMA stimulated adhesion of AML cells.
Histopathological outcome of Leishmania major‐infected BALB/c mice is improved by oral treatment with N‐acetyl‐l‐cysteine
Authors: Rocha‐Vieira Etel , Ferreira Ellen , Vianna Priscila , De Faria Daniela R. , Gaze Soraya T. , Dutra Walderez O. , Gollob Kenneth J. 
Published: March 2003

Summary Leishmania major infected BALB/c mice were treated with N‐acetyl‐l‐cysteine (NAC), a glutathione precursor, to evaluate the role of in vivo glutathione on lesion pathology and cytokine profiles following infection. Mice were maintained on NAC‐containing water 2 days before infection for a total of 14 weeks. The BALB/c response to L. major infection was improved by oral administration of NAC, at the level of histopathological outcome, lesion progression and cytokine profile. A significantly improved histopathological outcome of the footpad lesion, characterized by a mixed inflammatory infiltrate organized in a focal pattern with little tissue destruction and a reduced parasite load, was observed in NAC‐treated BALB/c mice. Histopathological modulation was accompanied by a modified cytokine pattern from popliteal lymph node cells, demonstrated by a sustained higher frequency of interferon‐γ (IFN‐γ) and tumour necrosis factor‐α (TNF‐α)‐producing cells. This work points to an important role for glutathione in the modulation of effector responses in BALB/c mice.