bluuebunny/crossref_metadata_2025 huggingface dataset:
Soluble complement receptor one (sCR1) inhibits the development and progression of rat collagen-induced arthritis
Authors: Goodfellow R M , Williams A S , Levin J L , Williams B D , Morgan B P
Published: March 2003

We set out to determine whether inhibition of complement using sCR1 could influence the development and progression of collagen arthritis in the Lewis rat. Collagen arthritis was successfully established in the Lewis rat, using a novel immunization schedule. In separate experiments, cobra venom factor (CVF) and sCR1 were used to achieve systemic complement inhibition. Their respective effects on disease onset and on the progression of established disease compared with saline-treated control animals was explored. Arthritis was assessed by measurement of clinical score, paw diameter and paw volume. Complement inhibition using either CVF or sCR1, prior to the onset of clinical signs of inflammation, delayed the development of disease. CVF was ineffective in the treatment of established disease, whereas sCR1 delayed the progression of disease in affected joints and prevented the recruitment of further joints while the animals were complement-depleted. In the control saline-treated groups the disease continued to progress relentlessly. We conclude that complement activation is important in the initiation and maintenance of inflammation in collagen arthritis. The potent disease-modulating effect of sCR1 provides persuasive evidence that specific complement inhibiting agents may be an effective approach to the treatment of inflammatory joint diseases
HIV-1 co-receptor expression on trophoblastic cells from early placentas and permissivity to infection by several HIV-1 primary isolates
Authors: Mognetti B , Moussa M , Croitoru J , Menu E , Dormont D , Roques P , Chaouat G
Published: March 2003

We examined CD4 and major HIV-1 co-receptor expression by trophoblast cells (TC) from early placentas, and the permissiveness of TC for infection by several natural HIV-1 isolates in vitro. Ten early placentas (4–6 weeks of gestation) from HIV−women were obtained after elective abortion. CD4 and HIV-1 co-receptor expression by TC was examined in terms of both mRNA and protein. The same TC were then challenged with three clinical HIV isolates of known phenotype, two originating from mothers who transmitted the virus to their child and one from a vertically infected newborn. TC infection was detected by polymerase chain reaction. CD4 expression was detected in five of the 10 placentas, while membrane protein expression of CCR3, CXCR4 and CCR5 was detected in every case, despite quantitative differences among individuals. Bonzo, GPR1 and ChemR23 mRNAs were detected in all TC preparations. TC from seven out of eight placentas were permissive to HIV entry, but no productive viral replication was detected (reverse transcriptase activity in culture supernatants). Interestingly, the addition of chemokine(s) or a CD4-blocking antibody to the cultures failed to inhibit TC virus entry. These data point to marked interindividual variability in HIV co-receptor expression by trophoblast cells and show that TC from early placentas can be infected in vitro by clinical HIV-1 isolates. They also suggest that viral entry in vitro might occur through a mechanism independent of both CD4 and chemokine receptors.
Chemokine synthesis and cellular inflammatory changes in lungs of mice bearing p40taxof human T-lymphotropic virus type 1
Authors: Miyazato A , Kawakami K , Iwakura Y , Saito A
Published: March 2003

To elucidate the pathogenic mechanisms of human T-lymphotropic virus type 1 (HTLV-1)-associated lung inflammation, we conducted a histopathological and molecular analysis study using transgenic mice bearing pX region of this virus. In these mice, accumulations of inflammatory cells consisting mainly of lymphocytes were present in peribronchiolar and perivascular areas and alveolar septa, while control littermate mice did not show such changes. In situ hybridization showed that the anatomic distribution of p40tax mRNA was similar to that of inflammatory cells, typically in peribronchiolar areas and to a lesser extent in perivascular and alveolar septa. Inflammatory cytokines, including IL-1β, tumour necrosis factor-alpha and interferon-gamma, and several chemokines, such as monocyte chemotactic protein-1 (MCP-1), RANTES, macrophage inflammatory protein-1α (MIP-1α) and IP-10, were detected in lungs of transgenic mice but not control mice. Semiquantitative analysis using reverse transcription-polymerase chain reaction showed a significant correlation between MCP-1 mRNA expression and p40tax mRNA, but not with other chemokines. The gene expression of the above chemokines, with the exception of MIP-1α, correlated with the severity of histopathological changes in the lung. Considered together, our results suggested that p40tax synthesis may be involved in the development of lung lesions caused by HTLV-1 through the induction of local production of chemokines.
Identification and immune regulation of 25-hydroxyvitamin D-1-α-hydroxylase in murine macrophages
Authors: Overbergh L , Decallonne B , Valckx D , Verstuyf A , Depovere J , Laureys J , Rutgeerts O , Saint-Arnaud R , Bouillon R , Mathieu C
Published: March 2003

Receptors for 1,25(OH)2vitaminD3 are found in most immune cells and important immunological effects have been described in vitro, reflected by its capacity to prevent autoimmunity and to prolong graft survival. The aim of this study was to examine the presence and nature of the enzyme responsible for final activation of the molecule, 1-α-hydroxylase, in murine macrophages and to analyse its regulation and possible role in the immune system. Peritoneal macrophages from C57Bl/6 mice were incubated with lipopolysaccharide (LPS; 100 μg/ml), interferon-gamma (IFN-γ; 500 U/ml) or a combination of both. By quantitative reverse transcriptase-polymerase chain reaction, using primers based on the murine renal cDNA sequence, low levels of 1-α-hydroxylase mRNA were detected in freshly isolated cells (18 ± 7 × 10−6 copies/β-actin copies). Analysis of the cDNA sequence of the gene revealed identical coding sequences for the macrophage and renal enzymes. mRNA levels rose three-fold with LPS (NS), but a six-fold increase was seen after IFN-γ stimulation (P < 0·05). Combining LPS and IFN-γ did not result in a major additional increase, but addition of cyclosporin A further increased levels 2·5-fold both in IFN-γ- and combination-stimulated cells (P < 0·05). Time course analysis revealed that up-regulation of 1-α-hydroxylase was a late phenomenon, preceded by the up-regulation of activating macrophage products such as IL-1 and tumour necrosis factor-alpha. Finally, a defect in 1-α-hydroxylase up-regulation by immune stimuli was found in autoimmune non-obese diabetic mice. In conclusion, we propose that the up-regulation of 1-α-hydroxylase in activated macrophages, resulting in the synthesis of 1,25(OH)2D3, might be a negative feedback loop in inflammation. A defect in this system might be an additional element in tipping the balance towards autoimmunity.
Cryofibrinogenaemia: a study of 49 patients
Authors: Blain H , Cacoub P , Musset L , Costedoat-Chalumeau N , Silberstein C , Chosidow O , Godeau P , Frances C , Piette J C
Published: March 2003

The purpose of this study was to characterize the clinical features and components of 30 patients with isolated cryofibrinogen (CF) versus those of 19 patients with combined CF and cryoglobulins (CG). Secondary forms of cryofibrinogenaemia associated with collagen disorders, infectious or malignant diseases, were significantly more frequent in patients with combined CF and CG than those with isolated CF (79 versus 47%, P = 0.02). Both groups of CF patients presented predominantly cutaneous symptoms (77% in isolated CF; 58% in combined CF + CG), and less frequently venous and/or arterial thrombosis (13% in isolated CF; 3% in combined CF + CG). Patients with idiopathic forms of CF, and particularly those without CG, suffered essentially from recurrent painful skin ulcers, mainly triggered by cold exposure. Patients with isolated CF had higher mean plasma concentrations of CF than those with combined CF + CG (1.61 ± 1.26 versus 0.82 ± 1.18 g/l, respectively; P = 0.004), but there was no correlation between the CF plasma level and either the severity of symptoms or the sensitivity to cold. In patients with isolated CF, fibronectin was suggested (by precipitation analysis) to be a major component of the cryoprecipitate, whereas immunoglobulins were rarely present (in only three out of 30 patients). By contrast, in the majority of patients (78%) with combined CF and CG, the CF consisted mainly of immunoglobulins of the same class as those characterizing the associated CG. Analysis of the CG precipitate revealed the presence of fibronectin but not fibrinogen, α1-antitrypsin and α2-macroglobulin. In conclusion, isolated and combined cryofibrinogenaemia are associated with different clinical signs requiring different clinical management, but there is no evidence as yet for a causal role of the cryoprecipitates in the differences observed.
The 19-kD antigen and protective immunity in a murine model of tuberculosis
Authors: Yeremeev V V , Lyadova I V , Nikonenko B V , Apt A S , Abou-Zeid C , Inwald J , Young D B
Published: March 2003

The 19-kD antigen is a cell wall-associated lipoprotein present in Mycobacterium tuberculosis and in bacille Calmette–Guérin (BCG) vaccine strains. Expression of the 19-kD antigen as a recombinant protein in two saprophytic mycobacteria—M. vaccae and M. smegmatis—resulted in abrogation of their ability to confer protection against M. tuberculosis in a murine challenge model, and in their ability to prime a DTH response to cross-reactive mycobacterial antigens. Induction of an immune response to the 19-kD antigen by an alternative approach of DNA vaccination had no effect on subsequent M. tuberculosis challenge. These results are consistent with a model in which the presence of the 19-kD protein has a detrimental effect on the efficacy of vaccination with live mycobacteria. Targeted inactivation of genes encoding selected antigens represents a potential route towards development of improved vaccine candidates.
Anti-β2-glycoprotein I (GPI) autoantibodies, annexin V binding and the anti-phospholipid syndrome
Authors: Hanly J G , Smith S A
Published: March 2003

We examined the role of autoantibodies to β2-GPI and prothrombin (PT) in the inhibition of annexin V binding to cardiolipin (CL) and the association with clinical manifestations of the anti-phospholipid syndrome (APS). Plasma samples from 59 patients with anti-phospholipid (aPL) antibodies were studied. Affinity purification of total IgG and IgG anti-ß2-GPI antibodies was performed using staphylococcal protein A and phospholipid liposomes. Annexin V binding to CL was significantly inhibited by 31/59 (53%) aPL+ plasma samples. There was a significant association between annexin V inhibition and elevated levels of IgG anti-cardiolipin (aCL) (r = −0.62; P < 0.001), IgG anti-ß2-GPI (r = −0.67; P < 0.001) and a weaker association with lupus anti-coagulant (r = −0.27; P = 0.05). There was no association with other isotypes of aCL and anti-ß2-GPI or with anti-PT of any isotype. In patients with clinical manifestations of the APS there were higher levels of IgG aCL (median (range) Z score): 10.0 (0–17.6) versus 5.0 (0–16.1); P = 0.03), IgG anti-ß2-GPI (4.5 (0–11.3) versus 0.9 (0–9.7); P = 0.02) and greater inhibition of annexin V binding to CL (−3.4 (−11.4–0.6) versus−1.1 (−10.8–1.2); P = 0.22). Odds ratios for the laboratory assays and the presence of clinical manifestations of the APS varied between 0.38 and 4.16, with the highest values for IgG aCL (4.16), IgG anti-ß2-GPI (3.28) and annexin V inhibition (2.85). Additional experiments with affinity-purified IgG antibodies indicated that inhibition of annexin V binding was dependent upon the concentration of ß2-GPI and anti-ß2-GPI antibodies. These results indicate that inhibition of annexin V binding to procoagulant phospholipid surfaces is dependent upon anti-ß2-GPI antibodies and suggest a role for annexin V in the pathogenesis of the APS.
Dysregulation in IL-12 secretion by neutrophils from HIV-infected patients
Authors: Vecchiarelli A , Monari C , Palazzetti B , Bistoni F , Casadevall A
Published: March 2003

It is generally believed that neutrophils from HIV-infected patients are functionally competent, but several studies have shown impairment in neutrophil fungal killing and cytokine production. In this study we evaluated the ability of neutrophils from healthy donors and HIV-infected patients to produce IL-12 in response to stimulation with Candida albicans, lipopolysaccharide (LPS) and Cryptococcus neoformans (acapsular and encapsulated), with and without MoAb opsonization. Neutrophils from healthy donors secreted IL-12 in response to LPS or C. albicans but not in response to encapsulated or acapsular C. neoformans, regardless of MoAb opsonization. Surprisingly, neutrophils from HIV-infected patients demonstrated constitutive IL-12 production, although these cells were not responsive to LPS stimulation. The inability of MoAb to C. neoformans capsular polysaccharide to promote IL-12 production by neutrophils excludes phagocytosis and/or CD16 cross-linking in this process, and distinguishes neutrophils from monocytes. Our results provide additional evidence for cytokine dysregulation in neutrophils from HIV-infected patients. Furthermore, the IL-12 response of neutrophils and monocytes to CD16 stimulation appears to be different, suggesting differences in the role of these phagocytic cells during the inflammatory response.
Autoantibodies in the sera of patients with rheumatic heart disease: characterization of myocardial antigens by two-dimensional immunoblotting and N-terminal sequence analysis
Authors: Tontsch D , Pankuweit S , Maisch B
Published: March 2003

The concept of antigenic mimicry in autoimmune diseases such as rheumatic fever has been under investigation for decades and the range of cross-reactive tissue antigens for streptococcal-induced antibodies identified in rheumatic heart disease is still expanding. To identify heart tissue-reactive antigens which may be implicated in the secondary immunopathogenesis of rheumatic fever, sera from 56 patients with acute rheumatic heart disease were probed in two-dimensional Western blots for reactivity against heart tissue antigens. After two-dimensional immunoblot analysis, proteins were submitted to N-terminal amino acid sequence analysis. This analysis identified creatine kinase, two mitochondrial proteins and, at a low level, various stress proteins as cross-reactive myocardial antigens. Therefore, in addition to myosin, creatine kinase may represent another major antigen for autoreactive antibodies in rheumatic heart disease. Mitochondrial proteins have been implicated in the pathogenesis of inflammatory heart disease for some years, and in this study we have identified two mitochondrial proteins as relevant antigens in rheumatic heart disease.
Expression of intercellular adhesion molecule-1 (ICAM-1) in nasal epithelial cells of atopic subjects: a mechanism for increased rhinovirus infection?
Authors: Bianco A , Whiteman S C , Sethi S K , Allen J T , Knight R A , Spiteri M A
Published: March 2003

Since clinical experimental studies indicate that upper respiratory tract viral infections may exacerbate acute asthma symptoms in atopic/asthmatic individuals, we have investigated the expression and modulation of ICAM-1 on human nasal epithelial cells (HNEC) from normal and atopic subjects. ICAM-1 is the attachment molecule for the majority of serotypes of human rhinovirus (HRV), including HRV-14, and is also critical for the migration and activation of immune effector cells. Basal ICAM-1 expression was significantly higher in HNEC obtained by brushings from atopic compared with non-atopic subjects (P = 0.031), and was also significantly increased on atopic HNEC harvested in season compared with out of season (P < 0.05). Atopic HNEC showed further up-regulation in ICAM-1 expression when cultured with clinically relevant allergen (P = 0.032). ICAM-1 levels on normal HNEC were also increased by infection with HRV-14 (P < 0.05). Basal expression of ICAM-1 on atopic nasal polyp epithelial cells (EC) was significantly higher than on both normal and atopic nasal HNEC. This elevated nasal polyp ICAM-1 level was not increased further by allergen, although HRV infection resulted in a small significant increase. Recovered viral titres from HRV-infected nasal polyp EC were 1.5-fold higher than from infected normal nasal HNEC. The data are consistent with the hypothesis that allergen, by enhancing expression of the HRV attachment target on host cells, facilitates viral infection in atopic subjects; simultaneously HRV-induced increases in ICAM-1 levels would favour migration and activation of immune effector cells to the airway, resulting in enhanced atopic inflammation.
Autoantigen-pulsed dendritic cells induce tolerance to experimental allergic encephalomyelitis (EAE) in Lewis rats
Authors: Huang Y-M , Yang J-S , Xu L-Y , Link H , Xiao B-G
Published: March 2003

Dendritic cells (DC) can modulate the nature of immune responses in a stimulatory or tolerogenic fashion. Great attention has been given to the induction of immunity to tumour and infection. In this study, bone marrow-derived DC from healthy Lewis rats were pulsed in vitro with encephalitogenic myelin basic protein peptide 68–86 (MBP 68–86), and injected subcutaneously (1 × 106/rat) into normal Lewis rats. Upon observation of the rats pretreated in this way for 4 weeks, when no clinical signs of EAE occurred, these rats were immunized with MBP 68–86 and Freund's complete adjuvant. The pretreated rats failed to develop clinical EAE. This tolerance was associated with augmented proliferative responses, interferon-gamma secretion, inducible nitric oxide synthase (iNOS) expression and NO production. The frequency of apoptotic cells was increased in the rats receiving MBP 68–86-pulsed DC compared with unpulsed control DC. Few infiltrating inflammatory cells were observed in spinal cord sections from rats that had received MBP 68–86-pulsed DC. The data are compatible with the interpretation that MBP 68–86-pulsed DC induce tolerance to EAE possibly through up-regulation of iNOS expression and NO production, which mediate cell apoptosis, thereby reducing infiltration of inflammatory cells within the central nervous system.
Pathogenic function of IL-1βin psoriasiform skin lesions of flaky skin (fsn/fsn) mice
Authors: Schön M , Behmenburg C , Denzer D , Schön M P
Published: March 2003

IL-1 acts on many cells as an inflammatory mediator. Its two forms, IL-1α and IL-1β, are regulated differentially within hyperproliferative inflammatory skin conditions, such as psoriasis. While IL-1α is down-regulated within psoriatic lesions, the levels of IL-1β are increased. However, some investigators have described an inactive form of IL-1β in psoriasis, while others have detected increased IL-1β activity within these lesions. Thus, its in vivo role remains unclear. We have assessed expression and function of IL-1β within psoriasiform skin lesions of the spontaneous mouse mutation flaky skin (fsn/fsn). It was found that IL-1β was increased by 357% within psoriasiform lesions of fsn/fsn mice compared with their wild-type or heterozygous (+/?) littermates (P < 0·00001). When the IL-1β function was inhibited by i.p. injection with a neutralizing MoAb, no effects were seen in +/? mice. In contrast, psoriasiform features in fsn/fsn mice were alleviated dramatically, as demonstrated by a 40% decrease of the epidermal thickness and a diminished number of intra-epidermal microabscesses. In addition, infiltrating epidermal CD4+ and CD8+ T cells were decreased by 68% and 81%, respectively (P < 0·05), and epidermal Langerhans cells also were reduced by 36% (P < 0·005). In contrast, mast cells were not affected, suggesting differential responses of various cutaneous cell types. Our results demonstrate an important in vivo role of IL-1β for the generation of hyperproliferative inflammatory skin lesions in the fsn/fsn model.
CD4+ and CD8+ T cell responses inHelicobacter pylori-infected individuals
Authors: Quiding-Järbrink M , Lundin B S , Lönroth H , Svennerholm A-M
Published: March 2003

In order to characterize T cell responses in human Helicobacter pylori infection, we have examined proliferative responses and cytokine production by CD4+ and CD8+ T cells isolated from duodenal ulcer patients and asymptomatic H. pylori carriers, after activation with some H. pylori antigens that may be important in disease development. For control purposes, T cells from uninfected volunteers were also examined. The different H. pylori antigens induced only modest proliferative responses in circulating CD4+ and CD8+ T cells from both H. pylori-infected and uninfected individuals. However, circulating T cells from H. pylori-infected subjects produced larger amounts of interferon-gamma (IFN-γ) in response to the Helicobacter antigens than did T cells from uninfected volunteers. Furthermore, CD8+ T cells produced larger amounts of IFN-γ than did CD4+ T cells, on a per cell basis. Most IFN-γ-producing cells from both infected and uninfected volunteers appeared to be naive T cells expressing CD45RA. Increased production of IL-4 and IL-5 was, on the other hand, only seen in a few instances after stimulation of isolated CD4+ and CD8+ T cells. Stimulation of freshly isolated gastric T cells with the different H. pylori antigens did not result in increased proliferation or cytokine production. In conclusion, our results show that several different purified H. pylori antigens induce production of IFN-γ, preferentially by CD8+ cells. Therefore, they suggest that IFN-γ-secreting CD8+ cells contribute significantly to the cytokine response induced by H. pylori infection.
Recombinant bacille Calmette–Guérin (BCG) expressing human interferon-alpha 2B demonstrates enhanced immunogenicity
Authors: Luo Y , Chen X , Han R , O'Donnell M A
Published: March 2003

To increase its immunostimulatory properties, BCG was genetically engineered to secrete recombinant human interferon-alpha 2B (rhIFN-α) under control of the mycobacterial heat shock protein (hsp)60 promoter and the α antigen signal sequence. Expression of rhIFN-α was readily detectable by ELISA and on Western blotting. When compared with control BCG, rhIFN-α BCG was substantially more active in inducing the production of IFN-γ and IFN-inducible protein 10 (IP-10) from human peripheral blood mononuclear cells, while IL-10 production was correspondingly decreased. These effects were reversible upon antibody neutralization of rhIFN-α. Among 10 patients tested, rhIFN-α BCG enhanced IFN-γ production in all patients ranging from 1·4- to 23·7-fold with a general trend toward greatest enhancement among those with weakest baseline responses to control BCG. Correspondingly, rhIFN-α BCG decreased IL-10 production in all patients by 1·2–4·8-fold. The onset of IFN-γ production induced by rhIFN-α BCG was also more rapid, occurring within 4 h after stimulation versus > 24 h with wild-type BCG. The observation that the maximum IFN-γ induction depends on the simultaneous presence of both IFN-α and BCG highlights the advantages of rhIFN-α BCG. Taken together, these immunostimulatory properties of rhIFN-α BCG suggest that it may be a superior agent for immunotherapeutic protocols involving live BCG in humans.
Influence of cytokines, monoclonal antibodies and chemotherapeutic drugs on epithelial cell adhesion molecule (EpCAM) and LewisY antigen expression
Authors: Flieger D , Hoff A S , Sauerbruch T , Schmidt-Wolf I G H
Published: March 2003

MoAbs against tumour-associated antigens (TAA) may be useful for the treatment of colorectal cancer. Since an increased expression of TAA may lead to enhanced antibody-dependent cellular cytotoxicity we examined whether the cytokines IL-2, IL-4, IL-6, IL-10, IL-12, interferon-alpha (IFN-α), IFN-γ, granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor and tumour necrosis factor-alpha can influence EpCAM and LewisY expression on the surface of the colorectal carcinoma cell lines HT29, LoVo and SW480. We found that only IFN-α increased significantly whereas IL-4 decreased both EpCAM and LewisY expression. IFN-γ significantly increased LewisY expression only. When tumour cells were treated with MoAb, the LewisY-specific MoAb BR55-2 down-regulated LewisY antigen expression, whereas MoAb 17-1A, which binds to EpCAM, up-regulated this TAA after 3 days of culture. The cytokines IFN-α or IFN-γ combined with MoAb 17-1A enhanced further slightly the expression of EpCAM. In additional experiments with chemotherapeutic drugs commonly used for the treatment of colorectal cancer, we found that 5-fluorouracil, mitomycin-C and oxaliplatin up-regulated EpCAM and LewisY antigen expression. Raltitrexed enhanced LewisY and down-regulated EpCAM expression, whereas CPT-11 had no influence at all. The highest expression for EpCAM on HT29 cells was achieved by the combination of IFN-α, 5-fluorouracil and MoAb 17-1A. Our results may be useful for defining combinations of biological and chemotherapeutic drugs for the treatment of colorectal cancer. Further trials should evaluate to what extent these combinations enhance antibody-dependent cellular cytotoxicity.
Opsonizing antibodies (IgG1) up-regulate monocyte proinflammatory cytokines tumour necrosis factor-alpha (TNF-α) and IL-6 but not anti-inflammatory cytokine IL-10 in mycobacterial antigen-stimulated monocytes—implications for pathogenesis
Authors: Hussain R , Shiratsuchi H , Phillips M , Ellner J , Wallis R S
Published: March 2003

Cachexia is one of the prominent features of advanced tuberculosis (TB) seen in association with increased expression of the monokine TNF-α. Several mycobacterial proteins, including PPD, stimulate TNF-α secretion from monocytes. Host factors that may play a role in cytokine expression from monocytes remain largely unknown. One such factor is the opsonizing antibodies. Monocytes have high-affinity receptors (FcγI and FcγIII) for IgG1 and IgG3 antibodies that mediate antigen uptake. We have reported selective up-regulation of IgG1 (which bind to Fcγ receptors) in advanced TB and have recently shown the ability of PPD-specific IgG1 antibodies to augment TNF-α expression in PPD-stimulated monocytes. These observations have now been extended to other cytokines with semipurified fractions from secreted antigens of Mycobacterium tuberculosis (containing 30 kD and 58 kD) that were devoid of lipids, glycolipids and carbohydrates. In the presence of heat-inactivated TB plasma containing known amounts of antigen-specific IgG1 antibodies, these fractions induced significantly increased TNF-α, IL-6 and IL-10 secretion. Absorption of IgG1 with Protein ‘A’ removed the augmenting activity for TNF-α and IL-6 secretion from the TB plasma samples. In the case of IL-10, removal of IgG1 resulted in increased rather than decreased IL-10 secretion. These results suggest a possible pathogenic role for antibodies in TB by enhancing proinflammatory and blocking down-regulatory cytokines such as IL-10 cytokines during the chronic phase of TB.
FTS reduces bleomycin-induced cytokine and chemokine production and inhibits pulmonary fibrosis in mice
Authors: Yara S , Kawakami K , Kudeken N , Tohyama M , Teruya K , Chinen T , Awaya A , Saito A
Published: March 2003

Bleomycin (BLM), an antitumour drug, is known to cause interstitial pneumonia followed by pulmonary fibrosis, and has often been used to produce an animal model of pulmonary fibrosis. In the present study, we examined the effect of a nonapeptide thymic hormone, facteur thymique serique (FTS), on the murine lung fibrosis induced by intratracheal instillation of BLM. Treatment with FTS ameliorated BLM-induced fibrotic changes in a dose-dependent manner, as indicated by the reduced accumulation of hydroxyproline (HP). In addition, FTS suppressed BLM-induced cellular inflammatory response in the lungs, as evidenced by inhibition of increased lung weight, reduced accumulation of inflammatory leucocytes, including lymphocytes and neutrophils, but not macrophages, and less pronounced histopathological changes. Finally, BLM challenge increased the local synthesis of proinflammatory cytokines, TNF-α and IL-1β and chemokines, MCP-1, MIP-1α RANTES, MIP-2 and KC, while administration of FTS suppressed the production of these cytokines, except for MCP-1. These effects of FTS were observed only when mice received intratracheal instillation with BLM. Considered collectively, our results indicated that FTS treatment ameliorated the cellular inflammatory responses and fibrotic changes in the lungs caused by BLM and such inhibition was well correlated with reduced synthesis of several fibrosis-related cytokines, and suggested that FTS may be potentially useful for the treatment of pulmonary fibrosis.
Pregnancy induces nonimmunoglobulin insulin-binding activity in both maternal and cord blood serum
Authors: Ronkainen M S , Hämäläinen A -M , Koskela P , Åkerblom H K , Knip M
Published: March 2003

To evaluate whether pregnancy has any effect on insulin antibody levels and to test the concordance between a conventional radioimmunoassay and a new microassay for the detection of insulin antibodies, insulin antibodies were analysed in 104 mothers in early pregnancy and at delivery and in their newborn infants. Thirty-eight of the mothers had type 1 diabetes. The concordance between the assays was high in the samples taken in early pregnancy (95%), but substantially lower in the samples taken at delivery (40%) and in the cord blood samples (68%). A considerable proportion of the mothers at delivery, especially the unaffected mothers (71%), and the newborn infants of the unaffected mothers (32%) were positive for insulin antibodies in the conventional assay but not in the microassay. Insulin antibody levels increased in the mothers, significantly so in the unaffected mothers (P < 0.001), during pregnancy in the conventional assay, whereas in the microassay they decreased significantly (P < 0.01) in affected mothers and remained negative in the unaffected mothers. Since immune complexes are precipitated with protein A specific for IgG in the microassay and with polyethylene glycol lacking specificity for immunoglobulins in the conventional assay, our data indicate that insulin antibody levels decrease on average during pregnancy and that the increasing non-IgG anti-insulin activity observed in the conventional assay is induced by pregnancy and is present in both the maternal and the foetal circulation.
Enhanced expression and production of monocyte chemoattractant protein-1 in myocarditis
Authors: Fuse K , Kodama M , Hanawa H , Okura Y , Ito M , Shiono T , Maruyama S , Hirono S , Kato K , Watanabe K , Aizawa Y
Published: March 2003

Monocyte chemoattractant protein-1 (MCP-1) is a member of the C-C chemokine family that has been shown to play a major role in the migration of monocytes and T cells to an inflammatory focus. To clarify the role of MCP-1 in the pathogenesis of myocarditis, we have examined the expression of MCP-1 in rat hearts with experimental autoimmune myocarditis (EAM), and have also measured serum levels of MCP-1 in patients with histology-proven acute myocarditis. Lewis rats were immunized with cardiac myosin and were killed 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 42 and 56 days after immunization. Large mononuclear cells in the myocardial interstitium were stained with an anti-MCP-1 antibody. mRNA of MCP-1 increased in the hearts of EAM rats from days 15–27 as shown by quantitative reverse transcription-polymerase chain reaction. Serum MCP-1 levels of the rats with EAM were significantly elevated from days 15–24. In the clinical study, serum levels of MCP-1 in 24 patients with acute myocarditis at the time of admission (165·2 ± 55·8 pg/ml) were significantly (P = 0·0301) elevated compared with those of 20 healthy volunteers (61·8 ± 10·7 pg/ml). Serum MCP-1 levels of 8 fatal cases (371·8 ± 145·2 pg/ml) were significantly (P = 0·0058) higher than those of 16 cases who survived (65·5 ± 12·8 pg/ml). In conclusions, MCP-1 may play an important role in the pathogenesis of human acute myocarditis as well as in the progression of rat EAM.
Differential responsiveness of cord and adult blood monocytes to hepatocyte growth factor
Authors: Jiang Q I , Azuma E , Tanaka M , Kobayashi M , Hirayama M , Kumamoto T , Iwamoto S , Yamamoto H , Nakashima K , Sakurai M , Komada Y
Published: March 2003

Monocytes as antigen-presenting cells play an important role in host defence. There are several cytokines affecting monocyte function. We demonstrate that both adult and cord blood monocytes constitutively express hepatocyte growth factor (HGF) receptor, MET. HGF significantly down-regulated MET expression of adult blood monocytes, compared with cord blood monocytes, when cultured either in RPMI-1640 containing 10% FBS or serum-free medium. Surface levels of MET correlated with c-met mRNA levels both in adult and cord blood when cultured. MET expression was down-regulated by treating with actinomycin D or cycloheximide. HGF stimulated DNA synthesis of adult monocytes, but not cord blood. HGF enhanced antigen-presenting capacity of adult blood monocytes but not cord blood monocytes. HGF up-regulated HLA class I expression in adult monocytes but not in cord blood monocytes. The current results suggest that the failure of cord blood monocytes to respond to HGF may be responsible, in large part, for their functional immaturity.
Acute myeloid leukaemia cells secrete a soluble factor that inhibits T and NK cell proliferation but not cytolytic function – implications for the adoptive immunotherapy of leukaemia
Authors: Orleans-Lindsay J K , Barber L D , Prentice H G , Lowdell M W
Published: March 2003

Evidence of an immune mediated graft-versus-leukaemia effect has led to the belief that T and NK cell based adoptive immunotherapy can constitute effective treatment for relapsed leukaemias. However, work on solid tumours has shown this strategy may be hampered, by an immune escape mechanism in which tumour secreted immunosuppressive factors compromise T and NK cell function. Indeed, acute myeloid leukaemia (AML) cells secrete immunosuppressive factors that block the synthesis of Th1 type cytokines in T cells. We demonstrate here that this immunosuppression, mediated by both HL60 AML cell line and primary AML blasts, inhibits T and NK cell proliferation but not cytolytic activity.

Supernatants from HL60 cell line and primary AML blasts inhibited T cell proliferation to mitogenic and alloantigen stimulation but had no effect on cytolytic function. Similarly, the proliferation of NK cells to IL-2 and IL-15 stimulation was inhibited whilst their cytolytic function, shown by lysis of AML blasts, K562 and Daudi cells remained unaffected. The failure of T and NK cells to proliferate was not due to effector cell apoptosis. Indeed, removal of lymphocytes from the immunosuppressive environment partially restored their capacity to respond to mitogenic stimulation. T cells exposed to immunosuppressive supernatants did not increase expression of mitotic inhibitory proteins that arrest cell division, thereby ruling this out as a mechanism of operation for this immunosuppression. T cell expansion requires antigen stimulation, usually provided in the form of AML blasts, therefore our data suggest that NK cells may be more practical for the immunotherapy of AML.
The influence of diesel exhaust particles on mononuclear phagocytic cell-derived cytokines: IL-10, TGF-βand IL-1β
Authors: Pacheco K A , Tarkowski M , Sterritt C , Negri J , Rosenwasser L J , Borish L
Published: March 2003

Diesel exhaust particles (DEP) are known to modulate the production of cytokines associated with acute and chronic respiratory symptoms and allergic respiratory disease. Tolerance is an important mechanism through which the immune system can maintain nonresponsiveness to common environmental antigens. We examined the effect of DEP on IL-10 and TGF-β, cytokines produced by macrophages and repressor (Tr-like) lymphocytes which influence tolerance. Human PBMCs (n = 22) were incubated with 1–100 ng/ml of DEP, and suboptimally primed with LPS. IL-10 gene expression was assessed by the S1 nuclease protection assay, and production of IL-10, TGF-β, TNF-α, IL-1β and IL-4 stimulated CD23 was evaluated by ELISA after 24 and 48 h. The effect of the order of exposure to DEP and LPS was evaluated on IL-10 protein and mRNA in cells (1) preincubated with LPS followed by DEP, or (2) exposed first to DEP followed by LPS. IL-10 was further evaluated using benzo[a]pyrene and [α]naphthoflavone as a surrogate for the polyaromatic hydrocarbons (PAHs) adsorbed to DEP. Control cells were incubated with carbon black, without PAHs. In PBMCs exposed to DEP with LPS, or preincubated with LPS before DEP, IL-10 production and mRNA fall significantly. TGF-β is similarly suppressed, IL-1β secretion is significantly stimulated, and IL-4 stimulated CD23 release rises in the atopic subjects. In contrast, when DEP is added prior to LPS, IL-10 production rises, and IL-1β falls to zero. These effects on IL-10 are reproduced with benzo[a]pyrene and reversed by the coaddition of [α]naphthoflavone, its known antagonist. The carbon black fraction has no effect on IL-10 production. The effect of DEP on IL-10 can be inhibitory or stimulatory, depending on the order of exposure to DEP and LPS. Pro-inflammatory cytokines and factors rise when IL-10 is inhibited, and are suppressed when IL-10 is stimulated. These results are duplicated with benzo[a]pyrene, suggesting that the PAH portion of the DEP is the active agent.
Th2 dominance in nasal mucosa in patients with Wegener’s granulomatosis
Authors: Balding C E J , Howie A J , Drake-Lee A B , Savage C O S
Published: March 2003

Wegener's granulomatosis initially affects upper respiratory tract organs including the nasal mucosa in more than 90% of patients. The inflammation is typically granulomatous with associated vasculitis. T lymphocytes are usually a prominent component of the leucocyte infiltrate. Previous studies using peripheral blood T cells have implicated IFN-γ rich Th1-type responses. This study addressed the cytokine milieu in nasal mucosa from 10 patients with active Wegener's granulomatosis using immunohistochemistry. Increased levels of CD3+ T cells and eosinophils were present compared with normal and disease controls. There was increased expression of IL-4, down-regulation of IL-2 and no detectable IFN-γ. There was increased expression of the chemokine receptor CCR3 by infiltrating cells, consistent with an IL-4 dominant, Th2-biased response. In contrast, renal biopsy tissue from 10 patients with active Wegener's granulomatosis showed expression of IL-2 and IL-4. The Th2-type environment within nasal mucosa, often the initial site of disease activity in Wegener's, is consistent with a local allergic response in these patients.
Prostaglandin E2 down-regulates viable Bacille Calmette–Guérin-induced macrophage cytotoxicity against murine bladder cancer cell MBT-2in vitro
Authors: YAMADA H , KURODA E , MATSUMOTO S , MATSUMOTO T , YAMADA T , YAMASHITA U
Published: March 2003

The regulatory effect of prostaglandin (PG) E2 and a cyclooxygenase (COX) inhibitor on Bacille Calmette–Guérin (BCG)-induced macrophage cytotoxicity in a bladder cancer cell, MBT-2, was studied in vitro. BCG stimulated thioglycollate-elicited murine peritoneal exudate cells (PEC) to induce cytotoxic activity and to produce cytokines such as interferon (IFN)-γ, tumour necrosis factor (TNF)-α and PGE2. NS398, a specific COX-2 inhibitor, and indomethacin (IM), a COX-1 and COX-2 inhibitor, enhanced viable BCG-induced cytotoxic activity and IFN-γ and TNF-α production of PEC. However, NS398 and IM did not enhance these activities induced by killed BCG. Enhanced cytotoxicity was mediated by increased amounts of IFN-γ and TNF-α. Exogenous PGE2 reduced cytotoxic activity and IFN-γ and TNF-α production of PEC. These results suggest that PGE2 produced by BCG-activated macrophages has a negative regulatory effect on the cytotoxic activity of macrophages. Accordingly, a PG synthesis inhibitor may be a useful agent to enhance BCG-induced antitumour activity of macrophages.
Treatment with methylprednisolone in relapses of multiple sclerosis patients: immunological evidence of immediate and short-term but not long-lasting effects
Authors: Martínez-Cáceres E M , Barrau M A , Brieva L , Espejo C , Barberà N , Montalban X
Published: March 2003

Relapses of multiple sclerosis (MS) are treated commonly with high-dose intravenous methylprednisolone (MP) given over a period of 3–5 days. The mechanisms responsible for the beneficial effects of MP in attacks are not clearly established. It is also controversial whether this treatment may have a long-term effect. Here, peripheral blood samples from relapsing–remitting MS patients in acute relapse were analysed by flow cytometry just before steroid treatment and at different time points after initiation of the therapy. We observed an immediate (day 3) decrease in the percentage of CD4+ lymphocytes, with a relative increase in the memory (CD4+CD45R0+) subpopulation. A longer standing effect of MP on IFN-γ production, CD54, CCR5, CXCR3 and CD95 (Fas) expression was also observed on CD4+ cells after 1 month of treatment initiation. Six months after the therapy, during clinical remission, no changes due to ivMP therapy were detected. These results support that MP treatment of relapses induces immediate post-treatment and short-term effects on the immune system that could partly account for the clinical and radiological improvement observed in MS patients. However, no conclussion can be drawn as to a possible long-term or even intermediate influence of ivMP treatment on the course of the disease.
Defining a T-cell epitope within HSP 65 in recurrent aphthous stomatitis
Authors: HASAN A , SHINNICK T , MIZUSHIMA Y , VAN DER ZEE R , LEHNER T
Published: March 2003

The 65 kD heat shock protein (HSP) has been implicated in the aetiology of recurrent aphthous stomatitis (RAS). We have previously demonstrated that peptide 91–105 derived from the sequence of mycobacterial 65 kD HSP stimulates specifically lymphocytes from patients with RAS. In this investigation, we show that both CD4+ and CD8+ T cells were significantly stimulated with mycobacterial peptide 91–105. In contrast, the human homologous peptide 116–130 stimulated only CD4+ T cells. Inhibition studies showed that CD4+ T cells were class II restricted, whereas CD8+ T cells were class I restricted. We then used truncated or substituted peptides, and demonstrated that residues 95–105 appear to be important, and residue 104(Arg) critical, in stimulating the T cells. Thus, peptide 95– 105 may constitute a T-cell proliferative epitope in RAS. We postulate that the high load of micro-organisms that colonize the oral mucosa may initiate an immune response by the microbial HSP 65-derived peptide 95–105, stimulating the numerous Langerhans cells in the oral mucosa to activate a cross-reacting immune response to the homologous peptide 116–130 within the epithelial HSP 60, initiating the immunopathological changes that lead to RAS.
Caspase activation in the absence of mitochondrial changes in granulocyte apoptosis
Authors: NOPP A , LUNDAHL J , STRIDH H
Published: March 2003

Eosinophils and neutrophils are two different types of granulocytes evolved from a common haematopoetic precursor in the bone marrow. Eosinophils are mainly involved in parasitic infection and allergic inflammation while neutrophils mainly participate in the defence against bacterial infections. Prolongation of granulocyte life span by inhibition of apoptosis may lead to tissue load of cells, and this has been detected in different inflammatory reactions. The molecular mechanisms and the potential role of the mitochondria in granulocyte apoptosis are poorly understood. In the present study we have characterized further the role of the mitochondria in granulocyte-apoptosis by studying the sequence of mitochondrial permeability transition (MPT) induction, loss of mitochondrial membrane potential (Δψm) and release of cytochrome c. This was made possible by applying tributyltin (TBT), a well-characterized apoptotic stimulus and MPT-inducer. We also studied potential differences in apoptosis-susceptibility between eosinophils and neutrophils. Ten minutes of TBT-exposure resulted in a substantial caspase-3 activity in both eosinophils and neutrophils, followed by phosphatidylserine (PS)-exposure after 30–120 min. Interestingly, caspase-3 activity was not preceded by MPT-induction, loss of Δψm or by cytochrome c-release in either eosinophils or neutrophils. In conclusion, we have demonstrated an extremely rapid induction of caspase-3 activity and apoptosis in human blood granulocytes without prior mitochondrial changes, including loss of mitochondrial membrane potential and release of cytochrome c. Our results open the possibility for a mitochondrial-independent activation of caspase 3 and subsequent apoptosis in granulocytes.
Suppression of autologous peripheral blood mononuclear cell proliferation by alveolar macrophages from young infants
Authors: BUNN H J , HEWITT C R A , GRIGG J
Published: March 2003

Maintenance of lung homeostasis involves a complex interaction between T lymphocytes and alveolar macrophages (AM), in which AM suppress pulmonary T cell proliferation to antigenic stimuli. To assess whether AM-mediated suppression is attenuated in healthy young infants, AM and peripheral blood mononuclear cells (PBMC) were sampled prior to elective surgery. Children were divided into <4 months of age (Group I) and >4 months (Group II). Autologous PBMC and AM were co-cultured in vitro with phytohaemaglutinin (PHA) at AM : PBMC ratios ranging from 2:1 to 1 : 5. Methyl-tritiated thymidine was added after 48 h and uptake determined at 72 h. Percentage suppression or enhancement of PBMC proliferation by AM was determined relative to proliferation of PBMC with PHA. To determine the role of soluble factors of suppression, cell-free supernatants from paediatric AM and PBMC co-cultures were added to PHA-stimulated adult PBMC. The median age was 3 months for Group I (n = 9) and 7 years 2 months (n = 13) for Group II. Percentage suppression of PBMC proliferation was attenuated in Group I (versus Group II) at AM : PBMC ratios of 2:1 (median 78%versus 92%, P < 0·05) and 1 : 1 (45%versus 87%, P < 0·01). Cell-free supernatants from Groups I and II suppressed proliferation of adult PBMC, but there was no difference in suppression between the age groups. We conclude that suppression of autologous PHA-stimulated PBMC proliferation by AM is attenuated in young infants, and this immaturity is not explained by reduced release of soluble factors.
Effect of arsenic, cadmium and lead on the induction of apoptosis of normal human mononuclear cells
Authors: DE LA FUENTE H , PORTALES-PÉREZ D , BARANDA L , DÍAZ-BARRIGA F , SAAVEDRA-ALANÍS V , LAYSECA E , GONZÁLEZ-AMARO R
Published: March 2003

The aim of this work was to investigate the effect of cadmium, lead and arsenic on the apoptosis of human immune cells. Peripheral blood mononuclear cells (MNC) were incubated with increasing concentrations of these metals and then cellular apoptosis was determined by flow cytometry and by DNA electrophoresis. We found that arsenic induced a significant level of apoptosis at 15 μm after 48h of incubation. Cadmium had a similar effect, but at higher concentrations (65 μm). In addition, cadmium exerted a cytotoxic effect on MNC that seemed to be independent of the induction of apoptosis. In contrast, concentrations of lead as high as 500 μm were nontoxic and did not induce a significant degree of apoptosis. Additional experiments showed that arsenic at concentrations as low as 1·0 μm had a significant pro-apoptotic effect when cells were cultured in the presence of this pollutant for more than 72 . Non-T cells were more susceptible than T lymphocytes to the effect of arsenic and cadmium. Interestingly, MNC from children chronically exposed to arsenic showed a high basal rate of apoptosis and a diminished in vitro sensibility to this metalloid. Our results indicate that both arsenic and cadmium are able to induce apoptosis of lymphoid cells, and suggest that this phenomenon may contribute to their immunotoxic effect in vivo.