bluuebunny/crossref_metadata_2025 huggingface dataset:
Tumour-specific cytotoxic T lymphocyte activity in Th2-type Sézary syndrome: its enhancement by interferon-gamma (IFN-γ) and IL-12 and fluctuations in association with disease activity
Authors: Seo N , Tokura Y , Matsumoto K , Furukawa F , Takigawa M
Published: March 2003

Sézary syndrome (SzS) is the leukaemic variant of cutaneous T cell lymphoma (CTCL), whose malignant T cells are of the Th2 type in most cases. In this study we investigated the tumouricidal activity of cytotoxic T lymphocytes (CTL) present in peripheral blood of a patient with Th2-type SzS, focusing on the effect of IL-2, IFN-γ and IL-12 on their cytotoxic activity, and the relationship between their lytic capacity and the patient's clinical course. At four different time points during a 2-month clinical period, CD4+ CD7− Sézary cells and CD8+ cells were separated from the patient's circulating cells. CD8+ cells were cultured with chemically attenuated, purified Sézary cells in the presence of IL-2 to develop specific cytotoxicity. The CD8+ cells thus cultured exhibited lytic activity against autologous Sézary cells. Concomitant addition of IFN-γ or IL-12 exerted a synergistic cytolytic effect with IL-2 on the tumour cells. Cytotoxicity inhibition studies using MoAbs revealed that the cytotoxicity operated in MHC class I-, CD8- and αβ T cell receptor-dependent manners. Furthermore, eight CD8+ T cell clones generated from cultured CD8+ cells exhibited a strong cytotoxicity against Sézary cells in an MHC class I-restricted fashion. During the clinical course, the activity of generated CTL and the number of CD8+ cells were inversely correlated with disease activity as assessed by the serum level of lactate dehydrogenase. These findings suggest that CTL down-regulate the growth of malignant T cells in this long-standing disease. Since Th2 cytokines such as IL-4 down-modulate CTL activity, CTL are assumed to be usually suppressed in SzS, whose malignant T cells are of Th2 type. It is likely that the administration of IFN-γ normalizes this Th2-skewing state, activates CTL, and thus exerts the therapeutic effectiveness in the treatment of CTCL.
Autoimmune thrombocytopenia (AITP) and thyroid autoimmune disease (TAD): overlapping syndromes?
Authors: Cordiano I , Betterle C , Spadaccino C A , Soini B , Girolami A , Fabris F
Published: March 2003

The pathogenesis of thrombocytopenia associated with TAD and the occurrence of overlapping traits between TAD and AITP are still a matter of debate. For this reason, we investigated for the presence and specificity of platelet and thyroid autoantibodies in 18 TAD patients with thrombocytopenia, 19 TAD patients without thrombocytopenia and in 22 patients with primary AITP without clinical signs of TAD. Platelet-associated IgG and/or specific circulating platelet autoantibodies were detected in 83% of patients with TAD and thrombocytopenia, in 10% of patients with TAD without thrombocytopenia and in 86% of patients with primary AITP. The reactivity of serum autoantibodies, assayed by MoAb immobilization of platelet antigens (MAIPA), was directed against platelet glycoproteins Ib and/or IIb/IIIa in 50% of the patients with TAD and thrombocytopenia, as in 46% of the patients with primary AITP. Thyroid autoantibodies were found in 89% of patients with TAD and thrombocytopenia, in 95% of patients with TAD without thrombocytopenia, and in 18% of patients with primary AITP. Thyrotropin (TSH) levels determined in three of four AITP patients with thyroid autoantibodies revealed a subclinical hyperthyroidism in one patient. The present study supports the autoimmune aetiology of thrombocytopenia associated with TAD, since the prevalence and specificity of platelet autoantibodies are similar in TAD and primary AITP. The results indicate also that there exists an overlap between thyroid and platelet autoimmunity with or without clinical manifestations.
Scleroderma fibroblasts promote migration of mononuclear leucocytes across endothelial cell monolayers
Authors: Denton C P , Shi-Wen X , Sutton A , Abraham D J , Black C M , Pearson J D
Published: March 2003

Perivascular infiltrates of inflammatory cells are a hallmark of lesional skin in scleroderma. We have explored the potential for scleroderma fibroblasts to modulate mononuclear leucocyte migration across endothelial cell monolayers in tissue culture, and to regulate expression of endothelial cell adhesion molecules. Fibroblasts were grown from skin biopsies of eight patients with active diffuse cutaneous scleroderma and from four healthy controls. Co-culture and conditioned medium transfer experiments examined the effect of soluble fibroblast products on mononuclear leucocyte (U937) cell migration across endothelial cell (1E-7) monolayers grown on tissue culture inserts. Co-culture of scleroderma, but not control fibroblasts, promoted transendothelial migration of U937 cells. Scleroderma fibroblast-conditioned medium had qualitatively similar effects and equivalent results were obtained using Jurkat-6 (T lymphocyte) cells, and with peripheral blood mononuclear cells from a patient with diffuse cutaneous scleroderma. Promotion of leucocyte migration does not appear to result from increased endothelial adhesion molecule expression, since fibroblast-conditioned medium did not up-regulate endothelial cell expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) or E-selectin. Moreover, leucocyte migration across cytokine-activated endothelial cell layers in co-cuture with fibroblasts was less than across resting cells, although the selective effect of scleroderma fibroblast co-culture persisted. Recombinant monocyte chemoattractant protein-1 (MCP-1) or IL-8 increased passage of mononuclear leucocytes across endothelial cell monolayers, whilst anti-MCP-1, but not anti-IL-8 antibodies, significantly reduced the effect of fibroblast conditioned medium. These data suggest that systemic sclerosis (SSc) fibroblasts promote leucocyte migration across endothelial cell monolayers in tissue culture via an MCP-1-dependent mechanism. These findings may be relevant to the perivascular mononuclear leucocyte infiltrates characteristic of early SSc lesions.
Differential expression of costimulatory molecules in chronic inflammatory periodontal disease tissue
Authors: ORIMA K , YAMAZAKI K , AOYAGI T , HARA K
Published: March 2003

Although B cell activation and subsequent immunoglobulin production are the immunopathological features of chronic inflammatory periodontal disease, in situ expression of costimulatory molecules in humoral immunity has not been investigated. In the present study we examined the expression of CD40, CD40 ligand (CD40L), CD80, CD86, CD28 and cytolytic T lymphocyte-associated antigen-4 (CTLA-4) on lymphocytes immunohistochemically. Cryostat sections were prepared from the gingival tissue samples of 14 patients with moderate to advanced adult periodontitis. In vitro kinetics of the expression of CD40L and CTLA-4 by peripheral blood T cells and that of CD80 and CD86 by peripheral blood B cells were also investigated by flow cytometry. Positive percentage expression of CD40L, CD28 and CTLA-4, and CD40, CD80 and CD86 was calculated for the number of CD3+ and CD19+ cells, respectively. Flow cytometric analysis demonstrated that the expression of CD40L and CTLA-4 on T cells, and CD80 and CD86 on B cells of peripheral blood was up-regulated upon activation. While most T cells and B cells expressed CD28, and CD80 and CD86, respectively, in gingival tissues, the expression of CD40L and CTLA-4 was lower but highly variable between specimens. Furthermore, these two molecules seemed to be expressed reciprocally in the lesion. As both CD40L and CTLA-4 expression are induced transiently by stimulation, variability in the expression of the molecules may reflect immunological activities and participation in the regulation of B cell activation of the lesion.
Experimental melanin-induced uveitis in the Fischer 344 rat is inhibited by anti-CD4 monoclonal antibody, but not by mannose-6-phosphate
Authors: SMITH J R , HART P H , PARISH C R , STANDFIELD S D , COSTER D J , WILLIAMS K A
Published: March 2003

Experimental melanin-induced uveitis (EMIU) is a rodent model of acute anterior uveitis which was described in 1993. We investigated strain susceptibility, and age and gender characteristics of the model, undertook histological and immunohistochemical studies to investigate underlying cellular mechanisms, and examined several treatment options. Rats were immunized with bovine ocular melanin (250 μg), and disease was followed by slit lamp examination. Lewis, Fischer 344 and Porton rats were found to be susceptible to EMIU, whereas Wistar-Furth, DA, and Hooded Wistar strains were resistant. EMIU was neither age- nor gender-dependent. In Fischer 344 rats, EMIU was characterized clinically by florid anterior segment inflammation. Histopathological findings included infiltration of ciliary body and iris with mononuclear cells and neutrophils. Both CD4+ and CD8+ T lymphocytes were prominent. Rats were then treated with intraperitoneal injections of anti-CD4, anti-CD8 or irrelevant isotype-matched MoAb on days −3, 0, 3, 6 and 9 with respect to melanin immunization. Incidence of uveitis was significantly reduced in rats treated with a non-depleting cocktail of anti-CD4 MoAbs (P = 0.007), whereas a depleting anti-CD8 antibody had no effect on the disease. Mannose-6-phosphate inhibits lymphocyte migration in some models of T cell-mediated inflammation. This simple sugar was administered to additional rats via intraperitoneal osmotic pumps for 14 days following disease induction, but did not influence the uveitis. We conclude that EMIU is controlled by CD4+ T cells, and disease may be abrogated by treatment with anti-CD4 MoAbs.
Th1 (IL-2, interferon-gamma (IFN-γ)) and Th2 (IL-10, IL-4) cytokine production by peripheral blood mononuclear cells (PBMC) from patients with systemic lupus erythematosus (SLE)
Authors: VIALLARD J F , PELLEGRIN J L , RANCHIN V , SCHAEVERBEKE T , DEHAIS J , LONGY-BOURSIER M , RAGNAUD J M , LENG B , MOREAU J F
Published: March 2003

We investigated the production of IL-2, IFN-γ, IL-10 and IL-4 by PBMC from 24 patients with SLE and 10 healthy individuals. Basal and mitogen-stimulated (lipopolysaccharide and phytohaemagglutinin (LPS + PHA)) cytokine production was determined in a whole blood assay (WBA). Supernatants were collected and assayed with specific ELISAs. Although the IL-2 and IFN-γ contents did not differ significantly between patients and controls under both conditions, statistically significant correlations were found between each cytokine and disease activity (SLAM index) after stimulation (respectively, r= 0.501, P = 0.01 and r = 0.631, P = 0.001). PBMC IL-10 production was significantly higher for patients than controls (P = 0.05), but no correlation between IL-10 levels and the SLAM index was obtained. IL-4 production was not statistically different between SLE patients and controls. For stimulated WBAs, the IL-10/IL-2 and IL-10/IFN-γ ratios were significantly correlated with disease severity (P = 0.02; P = 0.001, respectively). Overall, our data suggest that SLE is characterized by an elevated production of IL-10, reflecting the basal state of activation of the immune system. During exacerbation of SLE, IL-2 and IFN-γ are synthesized in larger amounts and may cause the tissue damage observed.
Mechanisms ofMycobacterium avium-induced resistance against insulin-dependent diabetes mellitus (IDDM) in non-obese diabetic (NOD) mice: role of Fas and Th1 cells
Authors: MARTINS T C , ÁGUAS A P
Published: March 2003

NOD mice spontaneously develop autoimmune diabetes. One of the manipulations that prevent diabetes in NOD mice is infection with mycobacteria or immunization of mice with mycobacteria-containing adjuvant. Infection of NOD mice with Mycobacterium avium, done before the mice show overt diabetes, results in permanent protection of the animals from diabetes and this protective effect is associated with increased numbers of CD4+ T cells and B220+ B cells. Here, we investigate whether the M. avium-induced protection of NOD mice from diabetes was associated with changes in the expression of Fas (CD95) and FasL by immune cells, as well as alterations in cytotoxic activity, interferon-gamma (IFN-γ) and IL-4 production and activation of T cells of infected animals. Our data indicate that protection of NOD mice from diabetes is a Th1-type response that is mediated by up-regulation of the Fas–FasL pathway and involves an increase in the cytotoxicity of T cells. These changes are consistent with induction by the infection of regulatory T cells with the ability of triggering deletion or anergy of peripheral self-reactive lymphocytes that cause the autoimmune disease of NOD mice.
The antigen-presenting environment in normal and human papillomavirus (HPV)-related premalignant cervical epithelium
Authors: MOTA F , RAYMENT N , CHONG S , SINGER A , CHAIN B
Published: March 2003

The activation of HPV-specific T cells within the cervical microenvironment is likely to play an important part in the natural history of cervical intraepithelial neoplasia (CIN). The extent and the type of T cell activation will depend critically on the expression of MHC, costimulatory cell surface molecules and cytokines by keratinocytes and Langerhans cells within the cervical lesion. Expression of MHC class II (HLA-DR and -DQ), costimulatory/adhesion molecules (CD11a/18, CD50, CD54, CD58 and CD86) and cytokines (tumour necrosis factor-alpha (TNF-α) and IL-10) was therefore investigated by immunohistochemistry in normal squamous epithelium (n = 12), low-grade (n = 23) and high-grade (n = 18) squamous intraepithelial lesions of the cervix. CIN progression was associated with de novo expression of HLA-DR and CD54, and increased expression of CD58 by keratinocytes. However, significantly, there was no expression of any adhesion/costimulation molecule by epithelial Langerhans cells in any cervical biopsy studied. Furthermore, TNF-α, a potent activator of Langerhans cells, was expressed constitutively by basal keratinocytes in normal cervix (12+/12), but expression of this cytokine was absent in a number of CIN samples (20+/23 for low-grade, 12+/18 for high-grade CIN). Conversely, the suppressive cytokine IL-10 was absent in normal epithelium (0+/12), but was up-regulated in a number of CIN lesions (12+/23 for low-grade, 8+/18 for high-grade CIN). The restricted expression of costimulation/adhesion molecules and the nature of the cytokine microenvironment within the epithelium may act to limit effective immune responses in some CIN lesions.
Functional expression of Fas and Fas ligand on human intestinal intraepithelial lymphocytes
Authors: MORIMOTO Y , HIZUTA A , DING E X , ISHII T , HONGO T , FUJIWARA T , IWAGAKI H , TANAKA N
Published: March 2003

Intestinal intraepithelial lymphocytes (IEL) constitute the first lymphoid compartment to encounter dietary antigens and intestinal pathogens. IEL are proposed to be involved in the defence against bacterial and viral invasion and to play an important role in mucosal immunity. Fas (CD95/APO-1) is a surface receptor that induces apoptotic cell death upon ligation with Fas ligand (FasL). The aim of this study was to examine the expression and function of Fas and FasL on freshly isolated normal human colonic IEL. The expression and function of Fas and FasL on IEL isolated from 40 normal colonic specimens were examined by flow cytometry, reverse transcriptase-polymerase chain reaction, immunohistochemistry, and DNA-release cytotoxicity assay. Virtually all CD3+ IEL (95.2 ± 4.3%) expressed Fas and were sensitive to agonistic anti-Fas antibody, whereas only 56.6 ± 8.4% of peripheral T lymphocytes expressed Fas and were resistant to the antibody. We also detected FasL mRNA and protein (40.1 ± 4.2%) on IEL, and found that IEL exerted FasL-mediated cytotoxicity against Fas-expressing target cells. These findings suggest that human IEL are activated in situ but are tightly regulated by the constitutive expression of functional Fas and FasL to maintain homeostasis of the mucosal immune system.
CD4 depletion in HIV-infected haemophilia patients is associated with rapid clearance of immune complex-coated CD4+ lymphocytes
Authors: DANIEL V , MELK A , SÜSAL C , WEIMER R , ZIMMERMANN R , HUTH-KÜHNE A , OPELZ G
Published: March 2003

The predominant immunological finding in HIV+ haemophilia patients is a decrease of CD4+ lymphocytes during progression of the disease. Depletion of CD4+ lymphocytes is paralleled by an increase in the proportion of immune complex-coated CD4+ cells. We examined the hypothesis that the formation of immune complexes on CD4+ lymphocytes is followed by rapid clearance of immune complex-coated CD4+ lymphocytes from the circulation. In this study, the relationship of relative to absolute numbers of immune complex-loaded CD4+ blood lymphocytes and their association with viral load were studied. Two measurements of relative and absolute numbers of gp120-, IgG- and/or IgM-loaded CD4+ lymphocytes were analysed in HIV+ and HIV− haemophilia patients, with a median interval of approx. 3 years. Immune complexes on CD4+ lymphocytes were determined using double-fluorescence flow cytometry and whole blood samples. Viral load was assessed using NASBA and Nuclisens kits. Whereas the proportion of immune complex-coated CD4+ lymphocytes increased with progression of the disease, absolute numbers of immune complex-coated CD4+ lymphocytes in the blood were consistently low. Relative increases of immune complex-coated CD4+ blood lymphocytes were significantly associated with decreases of absolute numbers of circulating CD4+ lymphocytes. The gp120 load on CD4+ blood lymphocytes increased in parallel with the viral load in the blood. These results indicate that immune complex-coated CD4+ lymphocytes are rapidly cleared from the circulation, suggesting that CD4+ reactive autoantibodies and immune complexes are relevant factors in the pathogenesis of AIDS. Relative increases of immune complex-positive cells seem to be a consequence of both an increasing retroviral activity as well as a stronger loading with immune complexes of the reduced number of CD4+ cells remaining during the process of CD4 depletion. The two mechanisms seem to enhance each other and contribute to the progressive CD4 decrease during the course of the disease.
Interferon-gamma (IFN-γ)- and tumour necrosis factor (TNF)-induced nitric oxide as toxic effector molecule in chronic dextran sulphate sodium (DSS)-induced colitis in mice
Authors: OBERMEIER F , KOJOUHAROFF G , HANS W , SCHÖLMERICH J , GROSS V , FALK W
Published: March 2003

Excess nitric oxide formation caused by the activity of the inducible nitric oxide synthase has been implicated as a toxic effector molecule in the pathogenesis of experimental colitis and inflammatory bowel disease. It was therefore investigated whether inhibition of this synthase or the cytokines TNF and IFN-γ, inducers of nitric oxide synthase, had effects on chronic colitis in mice. Chronic colitis was induced in mice by repeated feeding of DSS. Cytokines were neutralized by treatment with MoAbs and nitric oxide synthase was inhibited by aminoguanidine. The degree of colonic inflammation was assessed by a histological score and colon length. Aminoguanidine treatment reduced nitric oxide activity by 60% (P = 0.0004), the histological score by 31% (P = 0.005) and increased colon length by 1.4 cm (P = 0.002). Neutralization of TNF and IFN-γ resulted in increased colon length (0.7 cm, P = 0.07 and 0.8 cm, P = 0.03), improved histological score (19%, P = 0.045 and 25%, P = 0.013), and reduced nitric oxide activity (31%, P = 0.07 and 54%, P = 0.004) compared with controls. The combination of anti-cytokine treatments had additive effects. TNF and IFN-γ are involved in perpetuation of chronic DSS-induced colitis, and induction of excessive nitric oxide activity could be their common effector mechanism.
Characterization of phenotype and cytokine profiles of T cell lines derived from vitreous humour in ocular inflammation in man
Authors: MUHAYA M , CALDER V L , TOWLER H M A , JOLLY G , MCLAUCHLAN M , LIGHTMAN S
Published: March 2003

Intermediate uveitis (IU) and Fuchs’ heterochromic cyclitis (FHC) are two chronic ocular inflammatory disorders. They differ considerably in ocular morbidity, which is higher in IU. T cell lines were derived from the vitreous humour (VH) and peripheral blood (PB) of 10 patients with IU and four patients with FHC. There was a predominance of CD8+ in all the lines. However, there was a significantly higher percentage of CD4+ T cells in the T cell lines derived from VH of IU (32.0 ± 8.6%) compared with FHC patients (19.2 ± 8.9%) (P = 0.04). The VH-derived T cell lines (VDTC) produced significantly higher levels of IL-2, interferon-gamma (IFN-γ) and IL-10, but not IL-4, compared with PB-derived T cell lines (PBDTC) in both entities. There was significantly higher IL-2 production by VDTC from IU when compared with FHC patients (1810 ± 220 pg/ml versus 518 ± 94 pg/ml; P = 0.009), which could account for the more aggressive clinical features of this condition. In contrast IL-10 production was significantly higher by the VDTC from FHC compared with IU patients. The high IL-10 production by T cells infiltrating VH of FHC patients could down-regulate the inflammatory responses, thereby contributing to the benign clinical course seen in these patients. The accumulation of T cells with differing cytokine profiles in the VH suggests an important role for these cytokines in the pathogenesis of these chronic uveitides.
Protective role of NK1.1+ cells in experimentalStaphylococcus aureusarthritis
Authors: NILSSON N , BREMELL T , TARKOWSKI A , CARLSTEN H
Published: March 2003

In a model of Staphylococcus aureus-induced septic arthritis in C57Bl/6 mice we investigated the role of natural killer (NK) cells in the development of disease. Depletion of NK1.1+ cells was achieved by repeated injections of the PK136 antibody, whereas control mice received an irrelevant monoclonal antibody, O1C5.B2. Both groups of mice then received injections intravenously with 2 × 107 live S. aureus LS-1 secreting toxic shock syndrome toxin-1 (TSST-1). The mice were evaluated for 16 days with regard to weight, mortality and arthritis. Nine days after bacterial injection, 9/19 mice depleted of NK cells had developed arthritis compared with 1/17 in the control group (P = 0.01). The experiment was repeated twice with the same outcome. NK cell-depleted and control mice displayed the same degree of histopathological signs of arthritis at day 16. Depletion of NK cells did not affect uptake of bacteria by phagocytic cells in vitro, or bacterial clearance in vivo. In NK cell-depleted mice there was a tendency to increased levels of antibodies to TSST-1, whereas total immunoglobulin levels were similar to those in controls. NK cell depletion of non-infected mice did not affect the magnitude of inflammatory response during the T cell-dependent cutaneous DTH reaction to oxazolone, or during granulocyte-mediated inflammation. However, specific antibody responses to oxazolone were greatly increased in depleted animals. In conclusion, our study demonstrates that NK cells protect against arthritis during S. aureus infection. This outcome does not seem to be due to an influence on bacterial clearance, but could be due to an interaction with the host anti-inflammatory mechanisms.
DNA vaccination favours memory rather than effector B cell responses
Authors: LAYLOR R , PORAKISHVILI N , DE SOUZA J B , PLAYFAIR J H L , DELVES P J , LUND T
Published: March 2003

Following priming and boosting of mice with a DNA vector pEE6ΔS-hCGß expressing sequences encoding a transmembrane version of the β-chain of human chorionic gonadotropin (hCGβ), we failed to detect appreciable levels of specific antibody. However, subsequent challenge with hCG protein in Ribi adjuvant elicited a strong and rapid secondary immune response. This response was of comparable magnitude to that produced following priming, boosting and challenge with protein in adjuvant. Thus, DNA vaccination with this vector is as efficient in generating B cell memory as is conventional immunization, but the memory generation occurs in the absence of an overt effector response. Despite an overall similar level of specific antibody, the DNA-vaccinated mice produced hCG-specific antibodies biased towards IgG2a and IgG2b isotypes, whereas the protein-vaccinated mice produced higher levels of IgG1 antibodies. Both Th1 and Th2 cytokines (interferon-gamma (IFN-γ) and IL-4) were lower in the spleens of the DNA-immunized animals compared with the protein-Ribi-immunized animals, possibly suggesting a different level of helper T cell response to the two different modes of immunization.
Changing jejunal γδ T cell receptor (TCR)-bearing intraepithelial lymphocyte density in coeliac disease
Authors: ILTANEN S , HOLM K , ASHORN M , RUUSKA T , LAIPPALA P , MÄKI M
Published: March 2003

The function of jejunal intraepithelial γδ+ T cells is obscure, but they are commonly implicated as playing a role in inflammatory and autoimmune conditions. In coeliac disease (CoD), there are controversial reports as to gluten dependency of these cells. We have now studied the small bowel mucosal intraepithelial T cell densities, and the ratios of γδ+ to CD3+ T cells and γδ+ to αβ+ T cells during early disease development and on a gluten-free diet. Nine children initially excluded for CoD were followed up and rebiopsy after 0.8–4.5 years showed mucosal deterioration. Further, 21 biopsy specimens from newly diagnosed CoD patients were studied, together with 20 specimens taken from children on a gluten-free diet. During CoD development the density of γδ+ and αβ+ T cells as well as the ratios of γδ+ to CD3+ T cells and γδ+ to αβ+ T cells increased. In the latent stage of CoD when the small bowel mucosal architecture was still normal, two children had clearly normal densities of γδ+ (< 2.5 cells/100 epithelial cells) and αβ+ (< 25.0 cells/100 epithelial cells) T cells, and low ratios as well. In patients with newly diagnosed CoD the densities decreased significantly on a long-term gluten-free diet. We conclude that the density of intraepithelial γδ+ T cells as well as αβ+ T cells in CoD is gluten-dependent. CoD can develop in a child ingesting normal amounts of gluten and having normal jejunal mucosal morphology on biopsy and a normal density of γδ+ T cells.
Enhanced B cell survival in familial macroglobulinaemia is associated with increased expression of Bcl-2
Authors: Ögmundsdóttir H M , Sveinsdóttir S , Sigfússon Á , Skaftadóttir I , Jónasson J G , Agnarsson B A
Published: March 2003

A family with three cases of macroglobulinaemia of undetermined significance (MGUS), and one case each of immunoblastic lymphoma, Waldentröm's macroglobulinaemia and multiple myeloma was first described 20 years ago. We have previously identified 10 out of 35 healthy family members tested whose lymphocytes produced abnormally high amounts of immunoglobulins in culture. In the present study lymphocyte subpopulations of these hyper-responders have been further characterized and lymphocyte reactivity and survival in vitro have been studied. No differences were detected in the proportions of resting B lymphocytes (CD19+) co-expressing CD5, CD10, CD11b, or CD38, and the CD4/CD8 ratio of T cells was normal before and after stimulation with pokeweed mitogen (PWM). The initial rate of response in terms of immunoglobulin production was not increased, but immunoglobulin levels continued to rise during the second week of culture whereas the production peaked at 8 days in control cultures. This was associated with significantly greater survival of lymphocytes and at 14 days surviving B cells could only be identified in samples from hyper-responders. A lymph node removed because of tuberculosis from a family member 23 years before the diagnosis of multiple myeloma showed very marked Bcl-2 expression in a B cell follicle. This was not seen in a tuberculous lymph node from an unrelated subject. Stimulated cultures from three hyper-responders tested demonstrated significantly higher retention of Bcl-2 in B cells compared with one family control and six unrelated controls. We conclude that the increased production of immunoglobulins previously observed in this family with an inherited tendency for benign and malignant B cell proliferation is the result of enhanced B cell survival, which is associated with increased expression of Bcl-2 following stimulation.
T cell proliferation, MHC class II restriction and cytokine products of gliadin-stimulated peripheral blood mononuclear cells (PBMC)
Authors: O'keeffe J , Mills K , Jackson J , Feighery C
Published: March 2003

The immune response of PBMC to gliadin was investigated in patients with coeliac disease (CoD) by examining proliferation, MHC restriction and cytokine production. Gliadin induced low levels of proliferation in 63% of eight untreated patients, 32% of 28 treated patients and 35% of 31 healthy control subjects. In MHC restriction studies, the proliferative response to gliadin was inhibited (range 47–98% inhibition) in the presence of a MoAb to HLA-DR in each of three coeliac and three control donors studied. Using flow cytometry, increased expression of activation markers (HLA-DR and IL-2R) was demonstrated on gliadin-stimulated T cells from four of nine coeliac patients and three of seven healthy control donors. Cytokines were studied in culture supernatants using ELISA. Gliadin was a potent inducer of IL-6 and IL-10 in 100% of coeliac patients and controls, whereas IL-4 was not produced in either subject group. Gliadin induced IL-2 production in 40% of untreated patients, 42% of treated patients and 35% of healthy control donors. Interferon-gamma (IFN-γ) in gliadin-stimulated cultures was found only in coeliac patients, observed in 33% of untreated patients and 25% of treated patients. Spontaneous secretion of both IL-2 and IFN-γ was found more frequently in patients with untreated disease (87% of cases versus 21% of controls for IFN-γ and 40% versus 0% for IL-2). These results suggest, as manifest by IFN-γ production, that gliadin stimulates a Th1/Th0-like response in coeliac patients and a Th0-like response in healthy controls.
Suppressive effect of Chinese medicinal herb,Acanthopanax gracilistylus, extract on human lymphocytesin vitro
Authors: Shan B E , Yoshita Y , Sugiura T , Yamashita U
Published: March 2003

We studied the effect of a Chinese medicinal herb, Acanthopanax gracilistylus, extract (AGE), on human lymphocytes in vitro. AGE markedly suppressed the proliferative responses of human peripheral blood lymphocytes stimulated with mitogens concanavalin A (Con A) and Staphylococcus aureus Cowan I (SAC). Both T cell and B cell activities—production of interferon-gamma and immunoglobulin—were suppressed by AGE. The mechanism of AGE-induced suppression of lymphocytes is to arrest the cell cycle at the G0/G1 stage without a direct cytotoxic effect. AGE also suppressed the alloantigen-specific cytotoxic T lymphocyte response. However, natural killer cell activity was less sensitive to the suppressive activity of AGE. In contrast, AGE markedly enhanced monocyte function to produce cytokines. These activities of AGE were associated with a 60-kD protein which was sensitive to treatment with pronase E, but not with NaIO4. These results suggest that AGE has an immunomodulating activity on human lymphocytes and its properties could be clinically applied in the treatment of several diseases such as autoimmune and allergic diseases.
A lack of evidence for down-modulation of CD3ζ expression in colorectal carcinoma and pregnancy using multiple detection methods
Authors: Deakin A M , Singh K , Crowe J S , Ellis J H , Dalgleish A , Leicester R J , Finlayson C J , Miles W F A , Life P F
Published: March 2003

Loss of the T cell receptor-associated CD3 ζ chain has been proposed as a possible mechanism of the acquired immunosuppression in both tumour-bearing hosts, and in symptomatic patients with HIV infection. However, other reports suggest that the ζ-chain loss may in part be caused by protease activity of contaminating phagocytes ex vivo. Using flow cytometry and Western blot analysis on highly purified T cells, and ensuring adequate addition of protease inhibitors, we have studied the expression of CD3ζ on peripheral blood T cells from patients with colorectal carcinoma, and compared these with normal controls, and pregnant donors, as a further example of an immunocompromised state. Immunohistochemistry was performed on tumour sections from patients with colorectal carcinoma to measure CD3ζ expression in tumour infiltrating T cells, and compared with normal mucosa and tonsil. Using these three approaches, our data provide no evidence for downregulation of CD3ζ chain expression either in colorectal carcinoma or pregnancy and suggest that this explanation is unlikely to fully account for the reduced T cell function associated with these conditions in all patients.
Apoptosis of CD4+ T cells occurs in experimental autoimmune anterior uveitis (EAAU)
Authors: Yu H G , Chung H , Lee W J
Published: March 2003

To investigate the spontaneous turning off mechanism of endogenous uveitis, EAAU was induced in Lewis rats. Immunohistochemical and terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) stains revealed that CD4+ T cells were predominant in the uveal tissue of EAAU and that the apoptosis of these cells had occurred and progressed throughout the inflammatory period in EAAU eyes. The immunohistochemistry and in situ hybridization for Fas ligand (FasL) expression showed that the expression of Fas ligand was increased in the EAAU eyes compared with control eyes. These results suggest that the apoptosis of CD4+ T cells may play a key role in the spontaneous turning off mechanism of intra-ocular inflammation and that the induction of apoptosis may be mediated by the Fas–FasL system in EAAU.
Increased serum levels of solublel-selectin (CD62L) in patients with active systemic lupus erythematosus (SLE)
Authors: Font J , Pizcueta P , Ramos-Casals M , Cervera R , García-Carrasco M , Navarro M , Ingelmo M , Engel P
Published: March 2003

The adhesion molecule l-selectin (CD62L) mediates lymphocyte recirculation and leucocyte rolling on vascular endothelium at sites of inflammation. Serum levels of soluble l-selectin (sl-selectin) were measured in patients with SLE in order to relate these levels to clinical activity and immunological parameters. An ELISA was used to detect the soluble form of human l-selectin (CD62L) in 42 patients with SLE and in 33 healthy individuals. The mean ± s.e.m. values of sl-selectin were 1285 ± 121 ng/ml for patients with SLE and 986 ± 180 ng/ml for healthy blood donors, but there was no significant difference. When patients with active SLE were analysed, higher levels of circulating sl-selectin were found when compared with patients without activity (1497 ± 167 ng/ml versus 941 ± 150 ng/ml; P = 0.028). We found a significant correlation between the levels of sl-selectin and of dsDNA antibodies (r = 0.36, P = 0.044) and between levels of sl-selectin and SLE Disease Activity Index (SLEDAI) score (r = 0.42, P = 0.003). Patients with active SLE studied cross-sectionally showed significant elevations of sl-selectin (CD62L) compared with controls. Thus, the levels of this soluble adhesion molecule correlated with active disease and levels of anti-dsDNA antibodies.
Inhibition of Epstein–Barr virus (EBV)-specific CD8+ cytotoxic T lymphocyte (CTL) activity by soluble HLA class Iin vitro
Authors: Gansuvd B , Hagihara M , Munkhbat B , Kanai N , Morita N , Munkhtuvshin N , Chargui J , Kato S , Hotta T , Tsuji K
Published: March 2003

In the present study, the effects of soluble HLA (sHLA) class I molecules against EBV-specific CTL were examined. Two different sources of sHLA class I, either bioengineered spliced form of HLA-B7 (sB7) or natural production from EBV-transformed B cells (natural sHLA), were added during the induction of CTL or incubated with MHC-restricted CD8+ CTL, which were selected by immunobeads just before testing for their cytotoxic activity. Both sB7 and natural sHLA class I blocked the generation of CD8+ CTL and also inhibited the cytotoxic activity of established CTL in a dose-dependent manner. In both ways, natural sHLA class I was effective in 10-fold lower concentrations compared with sB7. The inhibitory effect did not require a sharing of the HLA allotypes between sHLA and the CTL. CTL, after being treated with sHLA, underwent apoptosis, which was considered here as the main mechanism.
The role of IL-12 in inflammatory activity of patients with rheumatoid arthritis (RA)
Authors: Kim W-U , Min S-Y , Cho M-L , Youn J , Min J-K , Lee S-H , Park S-H , Cho C-S , Kim H-Y
Published: March 2003

The aim of this study was to investigate the role of IL-12 in patients with RA. IL-12 (p70) and its associated cytokines were measured in sera and synovial fluid (SF) using an enzyme-linked immunosorbent method. Seven American College of Rheumatology (ACR) core set measures as well as IL-12 levels were sequentially monitored at the commencement and 4 months after treatment with a low-dose steroid and disease-modifying anti-rheumatic drugs (DMARDs). In sera, 64 (42.2%) of 152 RA patients had detectable concentrations of IL-12 (p70), whereas one (1.4%) of 69 osteoarthritis (OA) patients and five (10%) of 50 healthy controls had detectable IL-12 (P < 0.001). The median level of circulating IL-12 was also higher in RA patients (P < 0.001). In SF, the number of patients with detectable IL-12 and the median IL-12 levels were significantly higher in RA patients (n = 53) than in OA patients (n = 22). In paired samples (n = 53) of sera and SF from RA patients, IL-12 levels were higher in the SF than in sera (P < 0.001). Patients with detectable IL-12 (n = 51) in sera had higher tender joint scores (P = 0.003), swollen joint scores (P < 0.001) and C-reactive protein (CRP; P = 0.036), than those without (n = 55). Four months after treatment with DMARDs, the improved group showed a larger IL-12 decrease than the non-improved group (P = 0.017). The levels of IL-12 correlated positively with those of IL-2, interferon-gamma, IL-6, and tumour necrosis factor-alpha, but were correlated inversely with those of IL-10. Our results demonstrate that IL-12 levels reflect RA disease activity and that IL-12 is involved in the production of proinflammatory cytokines. An IL-12 blockade could be useful for the treatment of RA.
Pretreatment of mice with lipopolysaccharide (LPS) or IL-1β exerts dose-dependent opposite effects on Shiga toxin-2 lethality
Authors: Palermo M , Alves-Rosa F , Rubel C , Fernández G C , Fernández-Alonso G , Alberto F , Rivas M , Isturiz M
Published: March 2003

Haemolytic uraemic syndrome (HUS) has been closely associated with infection with a group of Shiga toxin-producing enterohaemorrhagic Eschericchia coli in young children. Shiga toxins (Stx) have been implicated as pathogenic agents of HUS by binding to the surface receptor of endothelial cells. LPS is a central product of the Gram-negative bacteria and several reports have documented that both LPS and Stx are important for disease development. In this study the reciprocal interactions between LPS and Stx2 are analysed in a mouse model. The results demonstrated that LPS was able to reduce or enhance Stx2 toxicity, depending on the dose and the timing of the injection. The involvement of the main early cytokines induced by LPS, tumour necrosis factor alpha (TNF-α) and IL-1β, in those LPS opposite effects on Stx2 toxicity was evaluated. Stx2 toxicity was enhanced by in vivo injection of murine TNF-α and low doses of murine IL-1β. However, at higher doses of IL-1β which induced corticosteroid increase in serum, Stx2 lethality was decreased. Considering that dexamethasone and IL-1β reproduce the LPS protective effects, it is suggested that endogenous corticosteroids secondary to the inflammatory response induced by LPS, mediate the protection against Stx2. It can be concluded that the fine equilibrium between proinflammatory and anti-inflammatory activities strongly influences Stx2 toxicity.
Changes in the cytokine profile of lupus-prone mice (NZB/NZW)F1 induced byPlasmodium chabaudiand their implications in the reversal of clinical symptoms
Authors: Sato M N , Minoprio P , Avrameas S , Ternynck T
Published: March 2003

We have previously observed that aged lupus-prone (NZB/NZW)Fl (BWF1) mice when infected with Plasmodium chabaudi show an improvement in their clinical lupus-like symptoms. In order to study the mechanisms involved in the long-lasting protective effect of the P. chabaudi infection in lupus-prone mice we analysed specific aspects of the cellular response, namely the profiles of cytokine mRNA expression and cytokine secretion levels in old BWF1 mice, in comparison with uninfected age-matched BWF1 mice and infected or uninfected BALB/c mice. Two months after infection, cells from BWF1 mice were stimulated with concanavalin A (Con A) and demonstrated a recovery of T cell responsiveness that reached the levels obtained with BALB/c cells. Old BWF1 mice showed high levels of interferon-gamma (IFN-γ) and IL-5 production and correspondingly low levels of IL-2 and IL-4 secretion before infection with P. chabaudi. Infection did not modify the IFN-γ levels of BWF1 T cells, whereas it considerably increased the secretion of the Th2-related cytokines IL-4, IL-5 and IL-10. In addition, only BWF1 T cells showed increased mRNA expression of tumour necrosis factor-alpha (TNF-α) and transforming growth factor-beta (TGF-β). This counter-regulatory cytokine network of infected BWF1 mice may be involved in the improvement of their lupus symptoms. The results of our investigations using the complex model of P. chabaudi infection can be extended and, by using more restricted approaches, it may be possible to explain the multiple regulatory defects of lupus-prone mice.
Comparison of the suppressive effects of soluble CR1 and C5a receptor antagonist in acute arthritis induced in rats by blocking of CD59
Authors: Mizuno M , Nishikawa K , Morgan B P , Matsuo S
Published: March 2003

We investigated the effects of suppression of complement activation at C3 level and inhibition of C5a on acute synovitis in rats. Acute synovitis was induced in Wistar rats by intra-articular (i.a.) injection into one knee of 0.3 mg of MoAb 6D1 (anti-rat CD59 antibody). In the treatment groups, soluble CR1 (sCR1) or C5a receptor (C5aR) antagonist was administered intra-articularly or intravenously and effects on the course of the acute synovitis were monitored. Synovitis induced by 6D1 was characterized by joint swelling, thickening of synovial tissue, cellular infiltration and deposition of membrane attack complex (MAC) on the synovial surface. Neither inflammatory change nor MAC deposition was found in rats which received an i.a. injection of sCR1 to suppress complement activity in the joint. Intra-articular injection of sCR1 did not reduce plasma complement activity. Intravenous administration of sCR1 suppressed plasma complement activity but had no effect on the course of the arthritis and synovitis with MAC deposition was observed. Neither i.a. nor i.v. injection of C5aR antagonist had any suppressive effects on inflammatory change or MAC deposition in synovium. The data show that inflammatory change induced by 6D1 was mediated by local complement activation and was not accompanied by systemic complement activation. C5a generation was not responsible for the observed inflammation, suggesting that other complement activation products, possibly MAC, mediate the inflammatory change observed in this model of acute synovitis in rats.
Clinical significance of serum soluble IL-2R levels in patients with adult T cell leukaemia (ATL) and HTLV-1 carriers
Authors: Araki K , Harada K , Nakamoto K , Shiroma M , Miyakuni T
Published: March 2003

The levels of soluble IL-2Rα (sIL-2Rα) in serum were measured in HTLV-1 carriers and ATL patients in order to evaluate their possible correlation with clinical status. Mean sIL-2R levels in ATL patients were found to be 9704 U/ml for the acute/lymphoma type, 1961 U/ml for the chronic type and 788 U/ml for the smouldering type. The level for asymptomatic HTLV-1 carriers was 475 U/ml, and 165 U/ml for healthy young adult HTLV-1− controls. The serial measurement of sIL-2R in ATL patients, healthy HTLV-1 carriers, and HTLV-1 carriers with diseases other than ATL showed a good correlation between serum levels of sIL-2R and the pathophysiological status of disease. Furthermore, an increase in the sIL-2Rα level in serum indicated the exacerbation of HTLV-1 infection and autoimmune diseases. The measurement of sIL-2Rα levels is therefore a very useful parameter for determining disease status.
Thromboxane A2 (TXA2) receptor blockade suppresses monocyte chemoattractant protein-1 (MCP-1) expression by stimulated vascular endothelial cells
Authors: Ishizuka T , Sawada S , Sugama K , Kurita A
Published: March 2003

In a previous study, it was reported that stimulation with a TXA2 receptor agonist, U46619, augments the expression of adhesion molecules by human umbilical vein endothelial cells (HUVEC). In the present study we showed that U46619 augments the expression of MCP-1 in HUVEC, both at the protein and mRNA levels. Pretreatment with TXA2 receptor antagonists greatly diminishes the extent of tumour necrosis factor-alpha (TNF-α)-, platelet-activating factor (PAF)-, or U46619-induced mRNA accumulation and production of MCP-1. Protein kinase C (PKC) inhibitors diminish U46619-induced mRNA accumulation and production of MCP-1. NAC, which inhibits nuclear factor κB (NF-κB) activation and activating protein 1 (AP-1) binding activity, inhibits the expression of MCP-1 at the protein and mRNA levels. These results indicate that in HUVEC stimulation via the TXA2 receptors augments MCP-1 production by induction of the NF-κB and AP-1 binding activity through the PKC system.
Multiple sclerosis is associated with an imbalance between tumour necrosis factor-alpha (TNF-α)- and IL-10-secreting blood cells that is corrected by interferon-beta (IFN-β) treatment
Authors: Özenci V , Kouwenhoven M , Huang Y-M , Kivisäkk P , Link H
Published: March 2003

The up-regulated B cell responses detectable in cerebrospinal fluid (CSF) and the augmented myelin antigen-specific T cell responses observed in the CSF as well as systematically in patients with multiple sclerosis (MS) suggest the involvement of cytokines in disease development and perpetuation. Here we report on the parallel involvement of TNF-α, IL-6, IFN-γ and IL-10 in MS and controls, using enzyme-linked immunospot (ELISPOT) assays to detect and enumerate cytokine-secreting mononuclear cells (MNC) prepared from blood and, for IL-6 and IL-10, from CSF without in vitro stimulation. MS is associated with elevated levels of TNF-α-secreting blood MNC when compared with levels in groups of control patients with myasthenia gravis (MG) and other neurological diseases (OND) or healthy subjects. This elevation was confined to patients with untreated MS and not present in those examined during ongoing treatment with IFN-β. Untreated patients with MS had lower numbers of IL-10-secreting blood MNC compared with the three control groups. In patients undergoing treatment with IFN-β, numbers of IL-10-secreting cells were in the same range as in controls. Normalization of TNF-α from elevated, and of IL-10 from decreased levels could be one reason for the beneficial effects of IFN-β in MS, although it remains to be shown whether these changes reflect phenomena primarily involved in MS pathogenesis or secondary changes. In CSF, levels of IL-10-secreting cells were higher than in blood in both MS and OND, with no difference between these groups. Systemic aberrations of IL-6 and IFN-γ and of IL-6 in CSF in MS versus controls were only minor, irrespective of treatment with IFN-β.