bluuebunny/crossref_metadata_2025 huggingface dataset:
Neutrophils play a critical role in the pathogenesis of experimental cerebral malaria
Authors: Chen L , Zhang Z-H , Sendo F
Published: March 2003

The role of neutrophils in experimental cerebral malaria (ECM) is not well understood. In this study we used a MoAb, RB6-8C5, to deplete the peripheral neutrophils of ECM-susceptible CBA/NSlc mice 24 h before Plasmodium berghei ANKA (PbA) infection. We found that early neutrophil depletion prevented the development of ECM and dramatically decreased the sequestration of monocytes and microhaemorrhage in the brain. The depletion of neutrophils also down-regulated tumour necrosis factor-alpha, interferon-gamma and IL-2 mRNAs and abrogated IL-12p40 mRNA expression in the brain as examined by competitive reverse transcriptase-polymerase chain reaction. Although depletion of neutrophils decreased the expression of Th1 cytokines in both spleen and brain, our results did not show the shift of a Th1 to a Th2 immune response since there was no obvious augmentation of expression of Th2 cytokine mRNAs (IL-4 and IL-10). We conclude that neutrophils play a role in the pathogenesis of ECM via enhancement of the expression of Th1 cytokines in the brain.
Diesel exhaust particles up-regulate expression of intercellular adhesion molecule-1 (ICAM-1) in human bronchial epithelial cells
Authors: Takizawa H , Abe S , Ohtoshi T , Kawasaki S , Takami K , Desaki M , Sugawara I , Hashimoto S , Azuma A , Nakahara K , Kudoh S
Published: March 2003

Epidemiological and experimental studies suggest that diesel exhaust particles (DEP) may play an active role in the increased respiratory mortality and morbidity. We have shown that DEP augmented the production of inflammatory cytokines by human airway epithelial cells in vitro. ICAM-1 has been shown to play an important role in the local accumulation of inflammatory cells. We studied the effect of DEP on ICAM-1 gene expression and surface expression in human bronchial epithelial cell line BEAS-2B. DEP (5–50 μg/ml) showed a stimulatory effect on ICAM-1 mRNA levels as evaluated by reverse transcription-polymerase chain reaction (RT-PCR). Flow cytometric analysis demonstrated an increased ICAM-1 expression on the epithelial cell surfaces. The soluble form of ICAM-1 molecules was also increased by the stimulation of DEP. In vitro neutrophil attachment onto DEP-stimulated epithelial cells was augmented, which was partially blocked by anti-ICAM-1 neutralizing antibody. Finally, these events were significantly inhibited by pretreatment with anti-oxidants pyrrolidine dithiocarbamate and N-acetyl cysteine, and p38 mitogen activated protein kinase (MAPK) inhibitor SB203580. These findings suggested that DEP induced up-regulation of ICAM-1 gene, and this process might be largely dependent on oxidant-mediated NF-κB activation and p38-MAPK pathways.
Detection of Bruton's tyrosine kinase mutations in hypogammaglobulinaemic males registered as common variable immunodeficiency (CVID) in the Japanese Immunodeficiency Registry
Authors: Kanegane H , Tsukada S , Iwata T , Futatani T , Nomura K , Yamamoto J , Yoshida T , Agematsu K , Komiyama A , Miyawaki T
Published: March 2003

CVID is frequently diagnosed in male and female individuals with hypogammaglobulinaemia of unknown aetiology. To examine the possibility that sporadic male cases with X-linked agammaglobulinaemia (XLA), which is caused by mutations in the Bruton's tyrosine kinase (Btk) gene, might be misregistered as having CVID, we employed a flow cytometric test to identify XLA in hypogammaglobulinaemic males registered as CVID in the Japanese Immunodeficiency Registry. From 30 male cases registered as having CVID between 1992 and 1998, we selected 21 males with low or unreported peripheral B cell counts. Blood samples could be obtained from 11 patients and their mothers. Using flow cytometric analysis, the Btk-deficient status in monocytes was demonstrated in seven out of nine cases with decreased numbers of peripheral B cells. The diagnosis of XLA was confirmed in each of the seven patients by demonstration of Btk gene mutations in the patients or cellular mosaicism in the mother. This study demonstrates misregistration of XLA as CVID.
T cell receptor repertoire and function in patients with DiGeorge syndrome and velocardiofacial syndrome
Authors: Pierdominici M , Marziali M , Giovannetti A , Oliva A , Rosso R , Marino B , Digilio M C , Giannotti A , Novelli G , Dallapiccola B , Aiuti F , Pandolfi F
Published: March 2003

DiGeorge syndrome (DGS) and velocardiofacial syndrome (VCFS) are associated with chromosome 22q11.2 deletion. Limited information is available on the T cell receptor (TCR) Vβ repertoire. We therefore investigated TCR Vβ families in lymphocytes isolated from blood and thymic samples of seven patients with DGS and seven patients with VCFS, all with 22q11.2 deletion. We also studied activities related to TCR signalling including in vitro proliferation, anti-CD3-induced protein tyrosine phosphorylation, and susceptibility to apoptosis. Reduced CD3+ T cells were observed in most patients. Spontaneous improvement of T cell numbers was detected in patients, 3 years after the first study. Analysis of CD4+ and CD8+ TCR Vβ repertoire in peripheral and thymic cells showed a normal distribution of populations even if occasional deletions were observed. Lymphoproliferative responses to mitogens were comparable to controls as well as anti-CD3-induced protein tyrosine phosphorylation. Increased anti-CD3-mediated apoptosis was observed in thymic cells. Our data support the idea that in patients surviving the correction of cardiac anomalies, the immune defect appears milder than originally thought, suggesting development of a normal repertoire of mature T cells.
Neutrophil lactoferrin release induced by IgA immune complexes differed from that induced by cross-linking of Fcαreceptors (FcαR) with a monoclonal antibody, MIP8a
Authors: Zhang W , Bi B , Oldroyd R G , Lachmann P J
Published: March 2003

The human IgA Fc receptor (FcαR, CD89) plays an important role in host defence against invading pathogens. To study the properties of the receptor, 12 MoAbs, namely, MIP7c, MIP8a, MIP9a, MIP10c, MIP11c, MIP14b, MIP15b, MIP38c, MIP59c, MIP65c, MIP68b and MIP71a, were generated. The inhibitory effects of the antibodies on FcαR functions were tested. Three of the antibodies, MIP7c, MIP8a and MIP59c, were able to block up to 90% of soluble FcαR binding to IgA-coated beads and 70–80% of neutrophil phagocytosis of IgA immune complexes (IC). MIP8a could also inhibit IgA IC-induced neutrophil lactoferrin release, while cross-linking of FcαR with MIP8a and anti-mouse IgG could elicit neutrophil lactoferrin release. However, IgA IC-induced lactoferrin release required both extracellular calcium and magnesium, whereas MIP8a-induced release did not require extracellular magnesium and only partially required extracellular calcium. In addition, the time course of IgA IC-induced lactoferrin release was slow. Lactoferrin was not detectable if the incubation time was less than 0·5 h. In contrast, MIP8a-induced lactoferrin release was fast. Lactoferrin could be detected within 5 min of incubation. Therefore, neutrophil lactoferrin release induced by IgA IC differed from that induced by cross-linking of FcαR with MIP8a.
Exogenous type-1 cytokines modulate mercury-induced hyper-IgE in the rat
Authors: Gorrie M J , Qasim F J , Whittle C J , Gillespie K M , Szeto C-C , Nicoletti F , Bolton E M , Bradley J A , Mathieson P W
Published: March 2003

Suppression of IgE responses is a major goal for immunotherapy, especially in the field of allergy. The Th2 subset of helper T cells plays a vital role in class switching of B cells to IgE production by releasing IL-4. In susceptible rat strains, mercuric chloride (HgCl2) induces activation of Th2 cells, with enhanced expression of IL-4, polyclonal B cell activation and very high levels of circulating IgE. We have previously shown that spontaneous regulation of this response coincides with enhanced expression of Th1/type-1 cytokines, including interferon-gamma (IFN-γ) and IL-12. We now report the effects of administration of exogenous type-1 cytokines on HgCl2-induced Th2 responses. At high doses, recombinant rat IFN-γ markedly reduced serum IgE levels. Recombinant mouse IL-12 was less effective at suppressing the IgE response following HgCl2, although it caused marked up-regulation of IFN-γ gene expression in the spleen. In Lewis rats, which are resistant to HgCl2-induced autoimmunity, a rise in serum IFN-γ was observed after HgCl2, but administration of polyclonal anti-IFN-γ antibodies did not render them susceptible to induction of a Th2 response by HgCl2. Our data show that individual type-1 cytokines are capable of suppressing the dramatic Th2 response induced by HgCl2 in the rat, even when they are not given until after starting HgCl2 administration. IFN-γ is a pivotal cytokine in ameliorating the Th2 response and measures aimed at selective up-regulation of this cytokine may be of therapeutic value in suppression of unwanted IgE responses.
Up-regulation of the tumour-associated marker CD44V6 in experimental kidney disease
Authors: Takazoe K , Foti R , Tesch G H , Hurst L A , Lan H Y , Atkins R C , Nikolic-Paterson D J
Published: March 2003

CD44 is an adhesion molecule involved in a wide range of cell–cell and cell–matrix interactions. The standard form of CD44 (CD44S) is a 85–90-kD glycoprotein, but alternative splicing of RNA encoding 10 variable exons (V1-V10) can give rise to many different CD44 variant protein isoforms of higher molecular weight. CD44 isoforms containing the V6 exon play a crucial role in tumour metastasis and lymphocyte activation. However, the role of CD44V6 in the kidney is unknown. The aim of this study was to examined renal CD44V6 expression in health, disease and in vitro. Immunohistochemistry staining with the V6-specific 1.1ASML antibody identified constitutive CD44V6 expression by occasional cortical tubular epithelial cells and medullary tubules in normal rat kidney. In immune-induced kidney disease (rat anti-glomerular basement membrane glomerulonephritis), there was a marked increase in CD44V6 expression by cortical tubules, particularly in areas of tubulointerstitial damage, which was associated with focal macrophage infiltration. There was also a marked increase in CD44V6 expression by damaged tubules in a model of non-immune kidney disease (unilateral ureteric obstruction). Reverse transcription-polymerase chain reaction revealed a complex pattern of CD44V6-containing mRNA isoforms in normal rat kidney. This pattern of CD44V6 splicing was essentially unaltered in disease. The NRK52E normal rat kidney tubular epithelial cell line expresses both CD44S and CD44V6. Stimulation of NRK52E cells with IL-1 or transforming growth factor-beta 1 induced a two-to-five-fold increase in the expression of both CD44S and CD44V6. Furthermore, triggering of NRK52E cells by antibodies to CD44S or CD44V6, but not isotype control antibodies, induced secretion of monocyte chemoattractant protein-1. In conclusion, this study has identified expression of the tumour-associated marker CD44V6 in tubular epithelial cells in normal and diseased rat kidney, and suggests that signalling through the CD44V6 molecule may participate in the pathogenesis of experimental kidney disease.
Glucocorticoids hamper theex vivomaturation of lung dendritic cells from their low autofluorescent precursors in the human bronchoalveolar lavage: decreases in allostimulatory capacity and expression of CD80 and CD86
Authors: Verhoeven G T , Van Haarst J M W , De Wit H J , Simons P J , Hoogsteden H C , Drexhage H A
Published: March 2003

Dendritic cells (DCs) were prepared from human bronchoalveolar lavage (BAL) cells. We previously reported that, in particular, the CD1a fraction of the low autofluorescent (LAF) cells contains the precursors for DCs: after overnight culture, 40% of the LAF cells change into functionally and phenotypically prototypic dendritic/veiled cells. There are, as yet, no data on the modulatory effects of glucocorticoids (GC) on the maturation and function of such DCs isolated from the human lung. Functional tests (allogeneic mixed lymphocyte reaction: allo-MLR) were therefore performed with CD1a+ LAF cells at different stimulator-to-T-cell ratios and after preincubation with different dexamethasone (DEX) concentrations. DEX caused suppression of the T-cell stimulatory capacity of CD1a+ LAF cells, which was dose-dependent, and more evident at the higher stimulator-to-T-cell ratios. Here, we also show that CD80 and CD86 are normally expressed at low levels on CD1a+ LAF cell-derived DCs compared to other DC populations. This low-level expression of costimulatory molecules is discussed here in relation to the previously reported low-level expression of CD80 (and CD86) on lung DCs in experimental animals. This appears to play a role in a predominant Th2 cell stimulating potential of DC from the lung environment. DEX exposure of CD1a+ LAF cells prevented the upregulation of even this low-level expression of CD80 and CD86. The veiled/dendritic morphology and the expression of other relevant cell surface markers and adhesion molecules was not affected by DEX exposure. It is concluded that DEX hampers the maturation of CD1a+ LAF cells into active lung DCs.
Treatment with a monoclonal antibody to IL-8 attenuates the pleocytosis in experimental pneumococcal meningitis in rabbits when given intravenously, but not intracisternally
Authors: Østergaard C , Yieng-Kow R V , Larsen C G , Mukaida N , Matsushima K , Benfield T , Frimodt-Møller N , Espersen F , Kharazmi A , Lundgren J D
Published: March 2003

The role of interleukin (IL)-8 as mediator in the recruitment of leucocytes into the CSF was investigated during experimental pneumococcal meningitis. Rabbits were inoculated intracisternally with approximately 106 CFU Streptococcus pneumoniae, and treated (i) intravenously with 5 mg of a monoclonal antibody to IL-8 (n = 7) or 5 mg of an isotype control antibody (n = 6); (ii) intracisternally with anti-IL-8, 100 µg (n = 5), 10 µg (n = 4), 1 µg (n = 4), 0·1 µg (n = 2). Ten rabbits served as untreated control group. Intravenous treatment with anti-IL-8 attenuated the pleocytosis significantly compared to untreated rabbits (P < 0·04) or rabbits treated with an isotype control antibody (P < 0·02). In contrast, intracisternal treatment with anti-IL-8 failed to attenuate the pleocytosis (P > 0·05). These results show, that IL-8 plays an important role in the recruitment of leucocytes during experimental pneumococcal meningitis, and that the functional activity of IL-8 in this process appears to be on the bloodstream side of the microvascular endothelium of the brain.
Secretory autoantibodies in primary biliary cirrhosis (PBC)
Authors: Palmer J M , Doshi M , Kirby J A , Yeaman S J , Bassendine M F , Jones D E J
Published: March 2003

It is unclear how breakdown in immune tolerance to the ubiquitous self-antigen pyruvate dehydrogenase complex (PDC), seen in the autoimmune liver disease PBC, gives rise to tissue damage with such a limited distribution (restricted to the liver and salivary and lachrymal glands). One property shared by these tissues is the ability to export secretory IgA by the process of transcytosis. The aim of this study was to address whether active transcytosis of anti-PDC IgA occurs across epithelial surfaces in PBC, a finding that might implicate mucosal specific immune mechanisms in the pathogenesis of this disease. Parotid saliva was collected from PBC patients (n = 44), normal controls (n = 28) and PBC patients post-liver transplantation (n = 11). IgA and secretory component-positive antibodies specific for human PDC were quantified by ELISA and immunoblotting. PBC patients (but not control subjects) had anti-PDC IgA in their saliva. The strong correlation seen between titres detected using anti-IgA and anti-secretory component antibodies suggests that this is predominantly secretory IgA reaching the saliva by the active process of epithelial transcytosis. Titres of anti-PDC IgA remain high in PBC patients saliva post-liver transplant. Findings from studies of IgA in viral infection models raise the possibility that anti-PDC IgA could, whilst undergoing transcytosis, bind to newly translated PDC components in the cytoplasm of the epithelial cells transporting them out of the cell and inducing metabolic damage. This model would, if correct, help to explain the mechanism and tropism of tissue damage in PBC and the aberrant pattern of expression of PDC on the apical surface of biliary and salivary epithelial cells reported in this disease.
Patients with systemic vasculitis have increased levels of autoantibodies against oxidized LDL
Authors: Swets B P , Brouwer D A J , Tervaert J W Cohen
Published: March 2003

Oxidation of low density lipoprotein (LDL) is considered to play an important role in the development of atherosclerosis and increased levels of autoantibodies against oxidized LDL have been found in patients with various manifestations of atherosclerosis. Patients with vasculitis are prone to the development of atherosclerosis. Since production of radical oxygen species in these patients may result in increased production of oxidized LDL (Ox-LDL), we hypothesized that antibodies against Ox-LDL are elevated during lesion development in vasculitis. Therefore we measured anti Ox-LDL antibodies in 25 patients with ANCA-associated vasculitis and in 42 healthy controls using an ezyme-linked immunosorbent assay (ELISA) in which malondialdehyde modified LDL (MDA-LDL) was coated on microtitre plates. Anti Ox-LDL antibodies were significantly higher in patients as compared to controls (P = 0·0001). Anti Ox-LDL levels were also measured in 11 patients during active disease and in these same patients during complete remission. Anti Ox-LDL levels were significantly higher in patients during active disease than during full remission (P = 0·001). Our results suggest that patients with ANCA-associated vasculitis are more susceptible to oxidation of LDL, which may contribute to accelerated atherosclerosis development.
Initiation of alcoholic fatty liver and hepatic inflammation with a specific recall immune response in alcohol-consuming C57Bl/6 mice
Authors: Slukvin I I , Boor P J , Jerrells T R
Published: March 2003

Whether immunological responses are involved in initiation and progression of alcoholic liver disease is unclear. We describe a mouse model of alcoholic liver injury characterized by steatosis and hepatic inflammation initiated by a recall immune response. Mice immune to Listeria monocytogenes fed a liquid diet containing ethanol and challenged with viable bacteria developed steatosis within 24 h and, at a later time, elevated serum alanine aminotransferase levels, indicating more liver damage in this group. Listeria antigen also induced steatosis and increased serum alanine aminotransferase levels in immune ethanol-consuming mice. The production of tumour necrosis factor by a recall immune response in this model is a major, but not the only, component in initiation of alcoholic liver disease.
Elongation factor 1 β/δ of Echinococcus granulosus and allergic manifestations in human cystic echinococcosis
Authors: Ortona E , Margutti P , Vaccari S , Riganò R , Profumo E , Buttari B , Chersi A , Teggi A , Siracusano A
Published: March 2003

Allergic reactions, such as urticaria, itching and anaphylactic shock, often complicate the course of cystic echinococcosis (CE). To investigate the role of the IgE-immunoreactive recombinant Echinococcus granulosus elongation factor-1 β/δ (EgEF-1 β/δ) in the allergic disorders during CE we determined humoral and cell-mediated responses to this antigen in patients with CE grouped according to the clinical presence or absence of allergic reactions. Immunoblotting analysis showed that serum IgE-binding reactivity to EgEF-1 β/δ differed significantly in patients with and without allergic reactions (38 of 42, 90% vs. 31 of 56, 56%; P < 10−4). EgEF-1 β/δ induced a proliferative response in 14 of 19 (74%) patients' peripheral blood mononuclear cells (PBMC) irrespective of the allergic manifestations and skewed Th1/Th2 cytokine activation towards a preferentially Th2 polarization. Epitope mapping identified an immunodominant epitope of 18 residues with 78% identity and 89% similarity with an IgE-immunoreactive Strongyloides stercoralis antigen. Overall these findings suggest that EgEF-1 β/δ is an allergenic molecule that may be a general marker of the intensity of CE immune response and that could lead to a deeper understanding of the specific antigen-induced mechanisms underlying allergic reactions in the human host.
γδT cells assistαβT cells in the adoptive transfer of contact hypersensitivity to para-phenylenediamine
Authors: Yokozeki H , Watanabe K , Igawa K , Miyazaki Y , Katayama I , Nishioka K
Published: March 2003

Para-phenylenediamine (PPD) is known to be a common sensitizer of allergic contact dermatitis and contact urticaria. To clarify the mechanism of contact hypersensitivity (CHS) to PPD, we established a mouse model of PPD-induced CHS. BALB/c mice were immunized for 3 consecutive days by painting topically a 2·5% PPD solution on their shaved abdominal skin. On days 5, 7 or 9 after the initial application, the mice were challenged by applications of a 2·5% PPD solution. Maximal ear swelling was determined at 24 h but another statistically significant and smaller ear swelling was observed 1 h after challenge with PPD in a hapten-specific manner. Adoptive cell transfer experiments demonstrated that the ear swelling of the adoptive cell transferred mice displayed an early response at 6 h and a late response from 12 h to 24 h when the recipient mice were challenged immediately after transfer. Both MoAbs and complement treatment of the transferred cells demonstrated that the phenotype of the early response cells which elicited a response at 6 h after challenge was Thy1+, B220+, αβ TCR, γδ TCR, CD3, CD4, CD5+ and CD8. The in vitro treatment of effector cells with MoAbs against not only αβ TCR but also γδ TCR, together with complement, was found to diminish substantially the late response, elicited 12–24 h after challenge. γδ T cells reconstituted the ability of αβ T cells to transfer 24 h CHS responsiveness. The phenotype of the γδ T cells that assist CHS effector αβ T cells was CD3+, CD4 and CD8+ and these regulatory γδ T cells were neither Ag-specific nor MHC-restricted. Furthermore, γδ T cells from normal spleen could also assist αβ T cells in adoptive transfer of the 24 h CHS response in a non-MHC-restricted manner. RT-PCR demonstrated that αβ T cells strongly expressed mRNA IFN-γ, whereas γδ T cells expressed not only IFN-γ but also IL-4 and IL-10. These data indicate that not only early response cells and αβ T cells but also Th2 type γδ T cells may play an important role in the elicitation of CHS to PPD.
Cooperation of interleukin-17 and interferon-γon chemokine secretion in human fetal intestinal epithelial cells
Authors: Andoh A , Takaya H , Makino J , Sato H , Bamba S , Araki Y , Hata K , Shimada M , Okuno T , Fujiyama Y , Bamba T
Published: March 2003

Interleukin (IL)-17 is a newly identified T cell-derived cytokine that can regulate the functions of a variety of cell types. In this study, we investigated the effects of IL-17 and interferon (IFN)-γ on chemokine secretion in human fetal intestinal epithelial cells. IL-8 and monocyte chemoattractant protein (MCP)-1 secretion by the human fetal intestinal epithelial cell line, intestine-407, was evaluated by ELISA and Northern blot. The expression of IL-17 receptor (R) was analysed by a binding assay using [125I]-labelled IL-17. The activation of nuclear factor-κB (NF-κB), NF-IL6 and AP-1 was assessed by an electrophoretic gel mobility shift assay (EMSA). IL-17 induced a dose-dependent increase in IL-8 and MCP-1 secretion. The inducing effects of IL-17 on IL-8 and MCP-1 mRNA abundance reached a maximum as early as 3 h, and then gradually decreased. IL-17 and IFN-γ synergistically increased IL-8 and MCP-1 secretion and mRNA abundance. IFN-γ induced a weak increase in IL-17 R mRNA abundance, and incubation with IFN-γ for 24 h enhanced [125I]-labelled IL-17-binding by 2·4-fold. IL-17 rapidly induced the phosphorylation and degradation of IκBα molecules, and the combination of IL-17 and IFN-γ induced a marked increase in NF-κB DNA-binding activity as early as 1·5 h after the stimulation. Furthermore, this combination induced an increase in NF-IL-6 and AP-1 DNA-binding activity. In conclusion, it becomes clear that IL-17 is an inducer of IL-8 and MCP-1 secretion by human fetal intestinal epithelial cells. The combination of IL-17 with IFN-γ synergistically enhanced chemokine secretion. These effects of IL-17 and IFN-γ might play an important role in the inflammatory responses in the intestinal mucosa.
Prevention of adjuvant arthritis by the W3/25 anti-CD4 monoclonal antibody is associated with a decrease of blood CD4+CD45RChigh T cells
Authors: Pelegrí C , Castell M , Serra M , Rabanal M , Rodríguez-Palmero M , Castellote C , Franch A
Published: March 2003

Imbalance between Th1 and Th2 functions is considered to play a key role in the induction and development of several autoimmune diseases, and the correction of that imbalance has led to effective therapies of some experimental pathologies. To examine whether CD4+CD45RChigh (Th1-like) and CD4+CD45RClow (Th2-like) lymphocytes play a role in the pathogenesis of adjuvant arthritis (AA) and in its prevention by anti-CD4 antibody, CD45RC expression on CD4+ T cells was determined in arthritic rats and in animals treated with an anti-CD4 MoAb (W3/25) during the latency period of AA. The phenotype of regional lymph node lymphocytes from arthritic rats in the active phase of the disease was determined by flow cytometry. Peripheral blood lymphocytes from rats treated with W3/25 MoAb were also analysed for 2 weeks after immunotherapy finished. IgG2a and IgG1 isotypes of sera antibodies against the AA-inducing mycobacteria, considered to be associated with Th1 and Th2 responses, respectively, were also determined by ELISA techniques. Fourteen days after arthritis induction, regional lymph nodes presented an increase in CD4+CD45RChigh T cell proportion. Preventive immunotherapy with W3/25 MoAb inhibited the external signs of arthritis and produced a specific decrease in blood CD4+CD45RChigh T cells and a diminution of antibodies against mycobacteria, more marked for IgG2a than for IgG1 isotype. These results indicate a possible role of CD4+CD45RChigh T lymphocytes in the pathogenesis of AA, and suggest that the success of anti-CD4 treatment is due to a specific effect on CD4+CD45RChigh T subset that could be associated with a decrease in Th1 activity.
C1q-bearing immune complexes induce IL-8 secretion in human umbilical vein endothelial cells (HUVEC) through protein tyrosine kinase- and mitogen-activated protein kinase-dependent mechanisms: evidence that the 126 kD phagocytic C1q receptor mediates immune complex activation of HUVEC
Authors: Xiao S , Xu C , Jarvis J N
Published: March 2003

Endothelial cells play a pivotal role in the initiation and perpetuation of inflammation. C1q, the first component of the classical pathway of complement, is a potent stimulus leading to endothelial cell activation and cytokine production. The specific cellular mechanisms through which endothelial cells are stimulated by C1q are not known. We stimulated human umbilical vein endothelial cells (HUVEC) with either monomeric C1q or C1q-bearing immune complexes (C1q-IC) in the presence or absence of inhibitors of protein tyrosine kinases (PTK) or mitogen-activated protein kinases (MAPK). C1q-IC, but not monomeric C1q, induced IL-8 production in dose- and time-dependent fashion. R3, a cross-linking monoclonal IgM antibody against the126 kD phagocytic C1q receptor (C1qR), also stimulated IL-8 production. IL-8 mRNA accumulation was detected by Northern blot analysis within 2 h of stimulation by the immune complexes and was enhanced by the addition of cycloheximide. Secretion of IL-8 by C1q-IC stimulated HUVEC was completely blocked by the PTK inhibitor, genistein or the MAPK inhibitor, UO126. These experiments demonstrate that C1q-IC-induced production of IL-8 in HUVEC is dependent upon the activation of PTK and MAPK. These findings also support a role for the phagocytic C1qR as an important activator of HUVEC by immune complexes.
Dietary n-3 polyunsaturated fatty acids modulate purified murine T-cell subset activation
Authors: Arrington J L , Chapkin R S , Switzer K C , Morris J S , McMurray D N
Published: March 2003

Studies in humans and murine disease models have clearly shown dietary fish oil to possess anti-inflammatory properties, apparently mediated by the n-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). To determine the mechanisms by which dietary EPA and DHA modulate mouse T-cell activation, female C57BL/6 mice were fed diets containing either 2% safflower oil (SAF), 2% fish oil (FO), or a 2% purified EPA/DHA ethyl ester mixture for 14 days. Splenic CD4 T cells (∼90% purity) or CD8 T cells (∼85% purity) were incubated with agonists which act at the plasma membrane receptor level [anti(α)-CD3/anti(α)-CD28], the intracellular level (PMA/Ionomycin), or at both the receptor and intracellular levels (αCD3/PMA). CD4 T cells stimulated with αCD3/αCD28 or PMA/Ionomycin proliferated and produced principally IL-2 (i.e. a Th1 phenotype), whereas the proliferation of CD4 T cells stimulated with αCD3/PMA was apparently driven principally by IL-4 (i.e. a Th2 phenotype). The IL-4 driven proliferation of putative Th2 CD4 cells was enhanced by dietary n-3 fatty acids (P = 0·02). Conversely, IL-2 production by αCD3/α CD28-stimulated CD4 T cells was reduced in FO-fed animals (P < 0·0001). The αCD3/αCD28-stimulated CD8 cells cultured from FO-fed animals exhibited a significant decrease (P < 0·05) in proliferation. There were no dietary effects seen in αCD3/PMA-stimulated CD8 cells, which produced both IL-2 and IL-4, or in PMA/Ionomycin-stimulated CD8 cells, which produced principally IL-2. These data suggest that dietary n-3 fatty acids down-regulated IL-2 driven CD4 and CD8 activation, while up-regulating the activation of the Th2 CD4 T-cell subset. Thus, the anti-inflammatory effects of n-3 fatty acids may result in both the direct suppression of IL-2-induced Th1 cell activation and the indirect suppression of Th1 cells by the enhanced cross-regulatory function of Th2 cells.
IFN-γsynergizes with TNF-αbut not with viableH. pyloriin up-regulating CXC chemokine secretion in gastric epithelial cells
Authors: Kraft M , Riedel S , Maaser C , Kucharzik T , Steinbuechel A , Domschke W , Luegering N
Published: March 2003

Helicobacter pylori colonizes the gastric epithelial surface and induces epithelial cells to increase production of the neutrophil attractant IL-8. Little is known about the role of the gastric epithelium in regulating mucosal T cell trafficking. We therefore characterized constitutive and regulated epithelial expression of the CXC chemokines IP-10, I-TAC and Mig, which specifically attract CXCR3 expressing CD4+ T cells. Human gastric epithelial cell lines (AGS, Kato III, NCI) were used to characterize the constitutive and regulated expression of three CXC chemokines in response to IFN-γ, TNF-α and different H. pylori preparations. Chemokine mRNA and protein production were measured by RT-PCR and ELISA. Gastric epithelial cells constitutively expressed mRNA for IP-10, Mig and I-TAC. IFN-γ in combination with TNF-α strongly induced secretion of those chemokines. Soluble or membranous fractions of H. pylori significantly inhibited IFN-γ/TNF-α induced epithelial cell IP-10 and Mig production. Gastric epithelial cells may contribute to mucosal T cell trafficking. The capacity of H. pylori products to inhibit IP-10 and Mig secretion may explain, at least in part, the failure to induce protective immunity against this bacterium and the ability of H. pylori to affect the presentation of the local inflammation.
CD45RA and CD45RO isoforms in infected malnourished and infected well-nourished children
Authors: Nájera O , González C , Toledo G , López L , Cortés E , Betancourt M , Ortiz R
Published: March 2003

The aim of this study was to determine if the distribution in vivo of CD4+CD45RA+/CD45RO− (naive), CD4+CD45RA+/CD45RO+ (Ddull) and CD4+CD45RO+ (memory) lymphocytes differs in malnourished infected and well-nourished infected children. The expression of CD45RA (naive) and CD45RO (memory) antigens on CD4+ lymphocytes was analysed by flow cytometry in a prospectively followed cohort of 15 malnourished infected, 12 well-nourished infected and 10 well-nourished uninfected children. Malnourished infected children showed higher fractions of Ddull cells (11·4 ± 0·7%) and lower fractions of memory cells (20·3 ± 1·7%) than the well-nourished infected group (8·8 ± 0·8 and 28·1 ± 1·8%, respectively). Well-nourished infected children showed increased percentages of memory cells, an expected response to infection. Impairment of the transition switch to the CD45 isoforms in malnourished children may explain these findings, and may be one of the mechanisms involved in immunodeficiency in these children.
Drug-induced neutropenia associated with anti-neutrophil cytoplasmic antibodies (ANCA): possible involvement of complement in granulocyte cytotoxicity
Authors: Akamizu T , Ozaki S , Hiratani H , Uesugi H , Sobajima J , Hataya Y , Kanamoto N , Saijo M , Hattori Y , Moriyama K , Ohmori K , Nakao K
Published: March 2003

Although antineutrophil antibodies are thought to be involved in drug-induced neutropenia, neither the precise mechanisms nor the particular antigens on the neutrophil surface have yet been clarified. Recently, we examined a patient with Graves’ disease who developed antineutrophil cytoplasmic antibodies (ANCA) after propylthiouracil treatment and exhibited neutropenia. Because several target antigens of ANCA are expressed on the surface of neutrophils, it was suggested that ANCA might contribute to neutropenia. The patient’s serum bound specifically to neutrophils and HL-60 cells differentiated into granulocytes, and lysed the HL-60 cells via a complement-mediated mechanism. Furthermore, two representative ANCA antigens, proteinase 3 and myeloperoxidase, significantly inhibited both the binding and cytotoxicity of the serum. Finally, tumour necrosis factor-α, which is known to up-regulate cell surface expression of several ANCA antigens, enhanced both the binding and cytotoxicity of the serum. These findings suggest that ANCA induced by propylthiouracil contributed to leucopenia through a complement-mediated mechanism.
Analysis of the B cell repertoire against autoantigens in patients with giant cell arteritis and polymyalgia rheumatica
Authors: SCHMITS R , KUBUSCHOK B , SCHUSTER S , PREUSS K-D , PFREUNDSCHUH M
Published: March 2003

The analysis of the antibody repertoire of patients with giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) might identify target antigens of the autoimmune response with potential relevance to our understanding of the pathogenesis of the disease and to the development of serodiagnostic tests. To detect such antigens, we screened a cDNA library derived from normal human testis for antigens reacting with IgG antibodies in the 1 : 250 diluted sera of three patients with untreated GCA using SEREX, the serological identification of antigens by recombinant cDNA expression cloning. Of 100 000 clones screened with each serum, six, 28 and six clones, respectively, were positive, representing a total of 33 different antigens. Most of the antigens reacted only with the serum used for identification and/or at a similar frequency with normal control sera. However, lamin C and the nuclear antigen of 14 kD reacted specifically with 32% of GCA/PMR, but with none of the control sera, while human cytokeratin 15, mitochondrial cytochrome oxidase subunit II, and a new gene product were detected preferentially, but not exclusively by sera from GCA/PMR patients. We conclude that patients with GCA/PMR develop antibodies against a broad spectrum of human autoantigens. Antibodies against human lamin C, the nuclear autoantigen of 14 kD as well as human cytokeratin 15, mitochondrial cytochrome oxidase subunit II and the product of a new gene should be investigated further to determine their value as tools for the diagnosis and/or the definition of clinical subgroups of patients with GCA/PMR.
Treatment of autoimmune diabetes recurrence in non-obese diabetic mice by mouse interferon-βin combination with an analogue of 1α,25-dihydroxyvitamin-D3
Authors: GYSEMANS C , VAN ETTEN E , OVERBERGH L , VERSTUYF A , WAER M , BOUILLON R , MATHIEU C
Published: March 2003

Autoimmune diabetes recurrence is in part responsible for islet graft destruction in type 1 diabetic individuals. The aim of the present study was to design treatment modalities able to prevent autoimmune diabetes recurrence after islet transplantation in spontaneously diabetic NOD mice. In order to avoid confusion between autoimmune diabetes recurrence and allograft rejection, we performed syngeneic islet transplantations in spontaneously diabetic NOD mice. Mice were treated with mouse interferon-β (IFN-β, 1 × 105 IU/day), a new 14-epi-1,25-(OH)2D3-analogue (TX 527, 5 μg/kg/day) and cyclosporin A (CsA, 7·5 mg/kg/day) as single substances and in combinations. Treatment was stopped either 20 days (IFN-β and CsA) or 30 days (TX 527) after transplantation. Autoimmune diabetes recurred in 100% of control mice (MST 11 days). None of the mono-therapies significantly prolonged islet graft survival. Combining CsA with TX 527 maintained graft function in 67% of recipients as long as treatment was given (MST 31 days, P < 0·01 versus controls). Interestingly, 100% of the IFN-β plus TX 527-treated mice had normal blood glucose levels during treatment, and even had a more pronounced prolongation of graft survival (MST 62 days, P < 0·005 versus controls). Cytokine mRNA analysis of the grafts 6 days after transplantation revealed a significant decrease in IL-2, IFN-γ and IL-12 messages in both IFN-β plus TX 527- and CsA plus TX 527-treated mice, while only in the IFN-β with TX 527 group were higher levels of IL-10 transcripts observed. Therefore, we conclude that a combination of IFN-β and TX 527 delays autoimmune diabetes recurrence in islet grafts in spontaneously diabetic NOD mice.
Spontaneous production of RANTES and antigen-specific IFN-γ production in macaques vaccinated with SHIV-4 correlates with protection against SIVsm challenge
Authors: AHMED R K S , MÄKITALO B , KARLÉN K , NILSSON C , BIBERFELD G , THORSTENSSON R
Published: March 2003

The β-chemokines, RANTES, MIP-1α and MIP-1β, have been implicated as being some of the protective factors in the immune response against human immunodeficiency virus (HIV) infection. We have presented data previously indicating that these chemokines also play a role in protective immunity against HIV/SIV infection in macaques. The aim of this study was to investigate the production of β-chemokines in eight cynomolgus macaques vaccinated with non-pathogenic SHIV-4 in relation to protection against pathogenic SIVsm challenge. Four control animals were also included in the study. Two of the vaccinated monkeys were completely protected and one was partially protected against the challenge virus. The monkeys that resisted infectious SIVsm virus challenge showed higher spontaneous β-chemokine production by peripheral blood mononuclear cells and had higher numbers of antigen-induced IFN-γ secreting cells compared to the non-protected animals. Our observations support our previous findings that the genetic background of the host and/or environmental factors are involved in the chemokine production and that β-chemokines contribute to protection against HIV/SIV infection.
In vivo activated T cells in rheumatoid synovitis. Analysis of Th1- and Th2-type cytokine production at clonal level in different stages of disease
Authors: GERLI R , BISTONI O , RUSSANO A , FIORUCCI S , BORGATO L , CESAROTTI M E F , LUNARDI C
Published: March 2003

T-cell cytokines play a crucial role in the pathogenesis and progression of rheumatoid arthritis (RA). Their detection in the joint, however, is impaired by the complex network present in the synovium. Although many synovial T cells show signs of previous activation, only a few express interleukin (IL)-2 receptor, marker of recent activation. The aim of this study was to analyse the cytokine production by in vivo activated (IL-2R +) T cells from RA at different stages of the disease. For this purpose, T cells were isolated from peripheral blood and synovial fluid of four patients with active RA, two at the onset of the disease, one in the early phase during treatment, one in long-lasting chronic phase. One patient was studied at the onset of the disease and 52 months later. Cells were initially expanded with a low dose of IL-2, cloned and analysed for cytokine production. The results showed a strong predominance of T helper (Th) 1 clones in the blood and a slight prevalence of Th0 clones in the joint of all the four patients. Interferon-γ and IL-2 production was higher in the long-lasting RA, whereas IL-4 synthesis was prevalent in early RA. Enrichment in IL-10-producing clones was present only in the joint of the untreated patients. The longitudinal study confirmed the differences in cytokine production between early and late phases of disease. These data confirm that RA is mainly a Th1-driven condition. However, in vivo activated synovial T cells produce also Th2-type anti-inflammatory cytokines, such as IL-4 and IL-10. The synthesis of both cytokines is a feature of the very early phase of RA, although the selective recruitment of IL-10-producing T cells is quickly lost.
The transmembrane form of TNF-αdrives autoantibody production in the absence of CD154: studies using MRL/Mp-Faslprmice
Authors: FUJII T , OKADA M , MIMORI T , CRAFT J
Published: March 2003

It is generally accepted that the interaction between CD40 and its ligand (CD154) plays a decisive role in contact-dependent help for T and B cells. In CD154-deficient MRL/Mp-Faslpr (MRL/lpr) mice, however, high titres of IgG2a-type autoantibodies against small nuclear ribonucleoproteins (snRNPs) are observed. We successfully isolated two CD154-deficient MRL/lpr Th1 lines, which could provide B cell help for anti-snRNP antibody production. The proliferative responses of the Th1 cell lines were MHC class II (I-Ek)-restricted. Although syngeneic B cell proliferation was induced by Th1 lines in both a contact-dependent and -independent manner, the soluble form of TNF-α (sTNF-α) was not involved in contact-independent B cell proliferation. On the other hand, both anti-TNF-α and TNF-receptor 2 (TNF-R2, p75) monoclonal antibody (MoAb) blocked contact-dependent B cell proliferation, suggesting that the transmembrane form of TNF-α (mTNF-α)–TNF-R2 co-stimulation participates in B cell activation. Similarly, anti-TNF-α and TNF-R2 MoAb inhibited anti-snRNP antibody production in vitro, but anti-CD154 or TNF-R1 MoAb did not. These results indicate that the interaction of mTNF-α on activated Th1 cells with TNF-R2 on B cells may be involved in the autoimmunity seen in MRL mice, and that the blockade of  CD40-CD154  co-stimulation  may  not  always  be  able  to  suppress  some  Th1-related  manifestations of lupus.
Loss of ileal IgA+ plasma cells and of CD4+ lymphocytes in ileal Peyer's patches of vitamin A deficient rats
Authors: BJERSING J L , TELEMO E , DAHLGREN U , HANSON L Å
Published: March 2003

Child mortality in diarrhoeal disease is increased significantly by vitamin A deficiency in poor countries. The pathological mechanisms are not known in detail. However, in this paper we report that vitamin A-deficient Wistar rats had much reduced IgA+ plasma cells in the ileal lamina propria (eightfold reduction from 470 cells/mm2, P = 0·009), as well as a prominent reduction of CD4+ cells in the parafollicular regions of ileal Peyer's patches (reduction from 7200 to 105 cells/mm2, P = 0·009). IL-2Ralpha-chain (CD25) positive lymphocytes in the ileal Peyer's patches were also reduced significantly in vitamin A deficiency (from 1400 to 300 cells/mm2, P = 0·009). The density of CD8 cells tended to be increased relative to the control animals (from 5100 to 6000 cells/mm2, not statistically significant). In conclusion, the marked decrease of lamina propria IgA+ plasma cells may be one cause of the high diarrhoeal mortality in vitamin A deficiency. This, in turn, appears to be related to reduced numbers of activated or regulatory CD4+ T cells in Peyer's patches.
Selective reduction of intestinal trefoil factor in untreated coeliac disease
Authors: CIACCI C , DI VIZIO D , SETH R , INSABATO G , MAZZACCA G , PODOLSKY D K , MAHIDA Y R
Published: March 2003

The trefoil factor family (TFF) encompasses small peptides of which intestinal trefoil factor (ITF) is expressed specifically in goblet cells of the small and large intestine. Previous studies have shown that ITF plays an important role in mucosal protection and repair. Coeliac disease represents a model of immune-mediated small intestinal inflammation and damage, with recovery on gluten-free diet. The aim of this study was to investigate the expression of ITF in the distal duodenal mucosa of subjects with coeliac disease, before and after treatment with a gluten-free diet. Expression of ITF and mucin in the distal duodenal biopsies from treated (n = 11) and untreated (n = 9) coeliac subjects and controls (n = 8) was investigated by immunohistochemistry and semiquantitative PCR. In untreated coeliac disease, there was reduction of ITF immunoreactivity in goblet cells but mucin expression was preserved. Mucosal recovery on gluten-free diet was associated with increased ITF immunoreactivity in goblet cells. There was also reduction in the expression of ITF transcripts, relative to MUC2 mRNA, in untreated coeliac duodenal samples, with recovery on gluten-free diet. Our study suggests that there is a selective reduction in the expression of the ITF gene in untreated coeliac disease. Recovery of ITF expression on a gluten-free diet suggests that the mucosal immune system regulates goblet cell differentiation and ITF expression in the human intestinal mucosa.
Prevalence of non-organ specific autoantibodies in HCV-infected subjects in the general population
Authors: MURATORI P , MURATORI L , STROFFOLINI T , PAPPAS G , TERLIZZI P , FERRARI R , LOFFREDA S , CASSANI F , RAPICETTA M , GUADAGNINO V , BIANCHI F B , LENZI M
Published: March 2003

The significance of non-organ specific antibodies (NOSAs) in HCV-related chronic hepatitis is largely unclear. In this study we evaluated the prevalence of NOSAs in a non-selected population of HCV-infected subjects. One hundred and seventy anti-HCV positive and 192 anti-HCV negative sex and age-matched subjects (median age 64 years, range 7–91 years, female 68%) enrolled from the general population of a small Italian town were evaluated for NOSAs by indirect immunofluorescence on rat tissue sections and HEp-2 cells, and by counterimmunoelectrophoresis with thymus and spleen extracts as the antigen source. One hundred and sixty-three (96%) HCV-infected subjects had normal ALT serum levels and no evidence of liver disease. NOSAs were found in 31 out of 170 (18%) anti-HCV positive subjects and in 20 out of 192 (10%) controls (P = NS), with similar median titre (1:40) and range (1:40 to 1:160). Neither liver/kidney microsomal antibody type 1 nor antiactin reactivity were detected. No significant association between NOSAs and HCV genotypes was observed. In the general population, HCV-infected subjects and healthy controls have a similar prevalence of NOSAs. Without continuous liver damage HCV infection is unlikely to induce the appearance of NOSAs.