bluuebunny/crossref_metadata_2025 huggingface dataset:
CD4 T cell recovery is slower in patients experiencing viral load rebounds during HAART
Authors: Scott-Algara D , Aboulker J-P , Durier C , Badell E , Marcellin F , PRUD'Homme M , Jouanne C , Meiffredy V , Brun-Vezinet F , Pialoux G , Raffi F
Published: March 2003

To determine whether viral load rebounds during HAART impact on CD4+ T cell recovery and immune reconstitution, we studied a prospective cohort of 355 antiretroviral naive patients enrolled to be randomized in a trial of three strategies of induction/maintenance HAART. The extent of immune reconstitution in blood through 72 weeks of antiretroviral treatment was evaluated. Lymphocyte subset markers (CD4, CD8, CD45RA, CD62L, CD16, CD19), activation markers (HLA-DR, CD38, CD25) were performed by cytometry analysis. Our results showed that plasma HIV-1 RNA was suppressed to below 500 copies per ml through week 72 in 240 patients (group 1) while the remaining 115 patients experienced at least one viral rebound (group 2). At baseline, CD4 cell count was higher and HIV-1 RNA was lower in group 1 than in group 2. Over 72 weeks, mean increase in CD4+ T cell count was 0·32 cell/mm3/day in group 1 and only 0·14 cell/mm3/day in group 2 (P < 0·0001). However, the patterns of changes in CD4+ and CD8+ T cell subsets during therapy were very similar across the two groups with only subtle and very limited differences. We conclude that permanent control of HIV replication could be necessary for faster immune reconstitution.
Accelerating the induction of Fas-mediated T cell apoptosis: a strategy for transplant tolerance?
Authors: Carroll H P , Ali S , Kirby J A
Published: March 2003

Acute allograft rejection is primarily a consequence of clonal expansion of donor-specific T cells with specificity for donor antigen. Immunosuppression current involves the administration of toxic drugs that limit lymphoproliferation, but this treatment is not antigen-specific and allows opportunistic infection. An ideal strategy would be production of donor-specific T cell tolerance in the presence of an otherwise intact and functional T cell repertoire. Methods to enhance normal apoptotic clearance of activated T cells might contribute to development of this state. This study focuses on manipulation in vitro of Fas-mediated T cell apoptosis and compares two methods to enhance the extent and kinetics for clearance of activated T cells. First, the CD4 coreceptor was cross-linked in the presence and absence of Fas-stimulation. It was found that CD4 cross-linking potently induced apoptosis, even in the absence of Fas stimulation. Resting and activated T cells were susceptible to this treatment, precluding the development of antigen-specific tolerance after T cell activation. In a second system, T cells were treated with two staurosporine analogues, Bisindolylmaleimide (Bis) III and VIII and apoptosis was induced by stimulation of Fas. Resting T cells remained resistant to Fas-mediated apoptosis, but treatment of mitogen or alloantigen-activated cells with either Bis III or VIII caused a synergistic increase in apoptosis. These agents also reduced the period of resistance to Fas-mediated apoptosis after T cell activation, possibly by reducing expression of c-FLIP, allowing early activation of caspase 8 in alloreactive T cells. Development of this strategy might provide a route to the induction of specific tolerance after organ transplantation.
Recognition of the 60 kilodalton cysteine-rich outer membrane protein OMP2 by CD4+ T cells from humans infected withChlamydia trachomatis
Authors: Goodall J C , Beacock-Sharp H , Deane K H O , Gaston J S H
Published: March 2003

T cell-mediated immunity is important in the control of chlamydia infection but chlamydia-specific T cells are also implicated in the inflammation and tissue damage which characterize chlamydia associated diseases. To investigate target antigens of the T cell-mediated immune response to chlamydia infection, Chlamydia trachomatis-specific CD4+ T cell clones were isolated from a patient with chlamydia-induced reactive arthritis. T cell immunoblotting indicated that an antigen of ∼60 kilodaltons molecular mass was recognized, and recombinant 60 kilodalton cysteine-rich outer membrane 2 (OMP2) proved to be stimulatory. By using deletion constructs and synthetic peptides an epitope presented by HLA-DRB1*0401 was defined and proved to contain the nonamer peptide within the OMP2 sequence predicted to have the greatest binding affinity for DRB1*0401 The sequence of the epitope is conserved in all C. trachomatis strains but not in C. pneumoniae. Investigation of patients with acute urethritis and additional patients with sexually acquired reactive arthritis showed that OMP2-reactive T cells were readily detectable in peripheral blood and synovial fluid. Thus OMP2 is a target antigen of the T cell-mediated immune response to CT infection.
Proliferation of T-cell subsets that contact tumour cells in colorectal cancer
Authors: Golby S J C , Chinyama C , Spencer J
Published: March 2003

We have investigated the proliferation rates of T-cell subsets in colorectal carcinomas using immunohistochemistry. It was found that the tumour-infiltrating T cells in contact with the tumour cells have a significantly higher frequency of proliferation than those in the stroma. In particular, the CD8+ intraepithelial lymphocytes (T-IEL) within the tumours have a significantly higher frequency of proliferation in comparison with CD8+ T cells in the stromal compartment or in any normal mucosal lymphoid tissues. It is possible that the proliferation of the CD8+ T-IEL may be driven by self-antigens expressed on the tumour cells. The proportion of CD3+ CD7– T cells is increased within carcinomas compared with the normal colon, and a population of CD57+ T cells was observed which is absent from the normal colon. It is possible that these phenotypes are acquired in situ due to repeated stimulation of the T cells by tumour antigens. Intact colorectal carcinoma explants were cultured, and the presence of tumour-infiltrating T cells analysed after 3 days of culture in isolation from the systemic compartments. CD3+ T cells were proliferating (at a low rate) within the explants after 3 days of culture, indicating that they may be sustained by factors present in the tumour microenvironment.
Is ageing associated with a shift in the balance between Type 1 and Type 2 cytokines in humans?
Authors: Sandmand M , Bruunsgaard H , Kemp K , Andersen-Ranberg K , Pedersen A N , Skinhøj P
Published: March 2003

The balance between Type 1 and Type 2 cytokines is important for the outcome of several infectious diseases. As elderly humans show increased morbidity and mortality from infectious diseases, this study tests if ageing is associated with a change towards Type 2 dominance in T cells. Expression of IFN-γ, and IL-4 was measured in CD4+ and CD8+ T cells by flow cytometry in three groups: young controls (n = 28), 81-year-olds (n = 22), and centenarians (n = 25). The major findings were that the percentage of IFN-γ+ as well as IL-4+ T cells was increased in aged subjects. Furthermore, after adjusting for decreased lymphocyte counts in the elderly, the concentration in the blood of IFN-γ+ and IL-4+ CD8+ T cells was still increased in the 81-year-olds. In centenarians, a shift towards a relative dominance of Type 2 cytokine expression was found within CD8+ T cells. Furthermore, the percentage of T cells with cytokine expression was closely correlated to the in vivo expression of CD95 and CD45RO. In conclusion, we found some evidence for an age-related shift towards a Type 2 cytokine profile.
Expression of eotaxin, an eosinophil-selective chemokine, parallels eosinophil accumulation in the vesiculobullous stage of incontinentia pigmenti
Authors: JEAN-BAPTISTE S , O'TOOLE E A , CHEN M , GUITART J , PALLER A , CHAN L S
Published: March 2003

Incontinentia pigmenti (IP) is an X-linked dominant genodermatosis primarily affecting female children. The initial vesiculobullous stage of IP is characterized clinically by inflammatory papules, blisters, and pustules, and histopathologically by acanthosis, keratinocyte necrosis, epidermal spongiosis and massive epidermal eosinophil infiltration. The cause of this multisystem disease is attributed to the mutations of an X-linked regulatory gene, termed nuclear factor-κB essential modulator (NEMO). The exact mechanism of epidermal eosinophil accumulation has not yet been determined. We explored the possible role of an eosinophil-selective, nuclear factor-κB-activated chemokine, eotaxin, in the accumulation of eosinophils in the initial stage of the disease. Monoclonal antibody (6H9) specific for human eotaxin strongly labelled the suprabasal epidermis of IP skin, paralleling the upper epidermal accumulation of eosinophils, but did not label the epidermis of normal skin or lesional skin from patients with other inflammatory skin diseases not characterized by prominent eosinophil accumulation, namely dermatitis herpetiformis and selected cases of atopic dermatitis lacking significant numbers of eosinophils. In addition, endothelial cells in lesional skin of IP also exhibited strong expression of eotaxin, which correlated with perivascular and intravascular eosinophil infiltration. We also examined the in vitro effects on epidermally derived eotaxin of several cytokines that were nuclear factor-κB-activated and/or known to induce eotaxin expression. In normal human keratinocytes, proinflammatory cytokines either independently (IL-1α) or synergistically (tumour necrosis factor-alpha (TNF-α)/ interferon-gamma (IFN-γ) and TNF-α/IL-4) up-regulated eotaxin expression. These studies suggest that release of cytokines during the initial inflammatory stage of IP induces epidermal expression of eotaxin, which may play a role in the epidermal accumulation of eosinophils.
Local immunostimulation induced by intravesical administration of autologous interferon-gamma-activated macrophages in patients with superficial bladder cancer
Authors: PAGÈS F , LEBEL-BINAY S , VIEILLEFOND A , DENEUX L , CAMBILLAU M , SOUBRANE O , DEBRÉ B , TARDY D , LEMONNE J-L ROMET , ABASTADO J-P , FRIDMAN W-H , THIOUNN N
Published: March 2003

We conducted a phase I/II clinical trial of the safety and efficacy of intravesical administration of autologous IFN-γ-activated macrophages (MAK) in patients with superficial bladder cancer. Monocyte-derived MAK cells were prepared in vitro and patients received six instillations of 1·4 × 108 to 2·5 × 108 cells, once a week, for five consecutive weeks. Treatment was well tolerated, with seven grade 1 and five Grade 2 protocol-related adverse effects. Nine out of 17 included patients had no recurrences during the year following the first instillation of MAK. The aim of the present study was to search for immune parameters related to local immunostimulation induced by MAK. Monitoring of the patients showed that urinary IL-8, GM-CSF and, to a lesser extent, IL-18 were increased following MAK instillations, with inter-individual differences. The urinary IL-8 level was about 10-fold higher than that observed for other cytokines, and its biological activity was reflected by a concomitant increase of urinary elastase, indicating neutrophil activation and degranulation. We also showed that nine out of 12 patients investigated presented an increase of urinary neopterin, a marker of IFN-γ-activated macrophages, 7 days after MAK instillation, while serum neopterin levels were almost stable. These results are in line with persistence of activated macrophages in the bladder wall after infusions. Moreover, there was evidence of macrophages in urine smears 2 months after the sixth MAK instillation, and the score of macrophages correlated with the quantity of neutrophils in the urine. Overall, this study provides evidence of a local immunostimulation induced by this novel and safe immunotherapeutic approach of MAK instillations in patients with superficial bladder cancer.
Expression and functional activity of CXCR-4 and CCR-5 chemokine receptors in human thymocytes
Authors: ZAMARCHI R , ALLAVENA P , BORSETTI A , STIEVANO L , TOSELLO V , MARCATO N , ESPOSITO G , RONI V , PAGANIN C , BIANCHI G , TITTI F , VERANI P , GEROSA G , AMADORI A
Published: March 2003

In this paper we addressed the expression of the HIV co-receptors CXCR-4 and CCR-5 in human thymocytes by phenotypic, molecular and functional approaches. Cytofluorimetric analysis disclosed that CXCR-4 was constitutively expressed by freshly isolated thymocytes (~10 000 molecules/cell in about 30% of thymocytes); the receptor was endowed with functional activity, as it mediated polarization, migration and intracellular Ca2+ increase in response to its ligand, SDF-1. On the contrary, CCR-5 expression in freshly isolated thymocytes was significantly lower (<4000 molecules/cell in less than 5% of the cells), and no functional response to CCR-5 agonists could be documented. Northern blot analysis of freshly isolated thymocytes showed high CXCR-4 mRNA levels, whereas the message for CCR-5 was barely detectable. On the other hand, a modest increase in the expression of CCR-5 was associated with in vitro thymocyte stimulation, and CCR-5 density at the cell surface attained CXCR-4 figures in most cases. None the less, no functional response to CCR-5 agonists could be documented in in vitro stimulated thymocytes. In vitro infection of thymocytes by CAT-expressing recombinant HIV bearing the envelope glycoproteins from different isolates showed that T-tropic strains, which use CXCR-4 as a co-receptor, were more efficient in infecting thymocytes than M-tropic strains, which preferentially use CCR-5. Altogether, these data indicate that expression of the major co-receptors involved in infection by M-tropic HIV strains is very poor in human thymocytes, and would suggest that thymocyte infection by M-tropic HIV strains may be a rare event in vivo.
Feeding NOD mice with pig splenocytes induces transferable mechanisms that modulate cellular and humoral xenogeneic reactions against pig spleen or islet cells
Authors: YOU S , GOUIN E , SAÏ P
Published: March 2003

We have reported previously that oral administration of pig cells to NOD mice modified xenogeneic cellular response against pig islet cells (PICs), and hypothesized that it may have induced active suppression. This preliminary report evaluated only the effect of feeding pig cells by ‘primary’ proliferation, i.e. when splenocytes from fed mice are confronted with pig cells in vitro. The present study also considered ‘secondary’ proliferation and cytokine production after feeding and subsequent in vivo graft of pig cells. Additionally, serum IgM and IgG isotypes were quantified by ELISA using pig target cells. Induction of active mechanism by feeding was hypothetical, which led us here to transfer splenocytes from mice fed pig spleen cells (PSC) and evaluate ‘primary’ (after transfer) and ‘secondary’ (after transfer and subsequent graft of pig cells) proliferations and cytokine secretions in recipient mice. We also determined whether the effects of feeding pig cells persisted after depression of suppressor mechanisms by cyclophosphamide. Mice fed with PSC displayed increased ‘primary’ splenocyte proliferation to PSC or PIC (P < 0·0001), while ‘secondary’ responses were decreased (P < 0·03) in those fed PSC and subsequently grafted with PSC. The increased ‘primary’ and decreased ‘secondary’ proliferations were reduced (P < 0·04) by pretreatment with cyclophosphamide. The IL-10/ and IL-4/IFNγ ratios produced in response to PSC increased (P < 0·04) in mice fed and grafted with PSC compared to those grafted only with PSC. IgM and IgG levels against pig cells were, respectively, increased (P < 0·04) and decreased (P < 0·04) in mice fed and grafted with PSC. IgG2a and IgG2b, but not IgG1, levels were lower (P < 0·01). These effects of feeding PSC on ‘secondary’ proliferation, cytokine and antibody productions, were not detected when mice were fed PSC only after graft with PSC. Transfer with splenocytes from mice fed PSC increased ‘primary’ proliferation of splenocytes from recipient mice in response to PSC (P < 0·02) or PIC (P < 0·05). After transfer with splenocytes from PSC-fed mice and graft with PSC, ‘secondary’ proliferation to pig cells were reduced (P < 0·04), and the IL-10/IFNγ ratio produced in response to PSC was increased fourfold. Thus, oral administration of PSC induces active transferable mechanisms, characterized by a biphasic pattern with early increased ‘primary’ xenogeneic cellular reactions to both PSC and PIC, followed by decreased ‘secondary’ responsiveness and a concomitant shift of the Th1/Th2 balance towards greater Th2 influence. Decreased responsiveness may be due to active suppression, even though induction of anergy or deletion cannot be excluded.
High levels of inflammatory cytokines are associated with poor clinical response to steroid treatment and recurrent episodes of type 1 reactions in leprosy
Authors: MANANDHAR R , SHRESTHA N , BUTLIN C R , ROCHE P W
Published: March 2003

Levels of leprosy antigen-induced interferon-gamma (IFN-γ), tumour necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) were measured in 96 leprosy patients with type 1 reactions (T1R) before, during and after a standard 12-week course of steroids. Peripheral blood mononuclear cells (PBMC) from leprosy patients with untreated T1R produced significantly more TNF-α than leprosy patients without T1R. Median levels of IFN-γ and TNF-α in T1R patients fell during treatment with steroids; however, TNF-α levels increased as the steroid dose was reduced. Median IL-10 levels increased throughout the steroid treatment period and were associated strongly with TNF-α levels. Patients with high cytokine levels had a poorer recovery of sensory or voluntary muscle nerve function, a higher risk of reactivation of symptoms during steroid treatment, and a higher risk of another episode of T1R within 2 months of completing the steroid regimen. Rapid and effective reversal of the inflammatory process in T1R is critical to prevent permanent nerve damage from T1R and monitoring cytokine levels during treatment may be useful.
Ganglioside expression in tissues of mice lackingβ2-microglobulin
Authors: MARKOTIC´ A , MARUSˇIC´ A , TOMAC J , MUüTHING J
Published: March 2003

This study presents a comparative analysis of gangliosides from lymphoid (spleen and thymus) and other (brain, liver, lungs and muscle) tissues of C57BL/6 mice lacking the gene for β2-microglobulin (β2M), a constitutive component of the MHC class I molecule. Ganglioside fractions in the tissues of mice homozygous (β2M−/−) and heterozygous (β2M−/+) for the gene deletion were determined by high performance thin-layer chromatography (HPTLC), followed by immunostaining with specific polyclonal antibodies. Ubiquitous gangliosides GM3(Neu5Ac) and GM3(Neu5Gc) were the dominant gangliosides in the lungs of the control β2M−/+ mice, whereas the homozygous knockout mice had substantially decreased expression of these structures. The lungs of the β2M−/− mice also had reduced expression of T-lymphocyte-specific GM1b-type gangliosides (GM1b and GalNAc-GM1b). β2M-deficient mice also had more GM1a and GD1a gangliosides in the liver, and several neolacto-series gangliosides were increased in the brain and lungs. This study provides in vivo evidence that the β2M molecule can influence the acquisition of a distinct ganglioside assembly in different mouse organs, implicating its non-immunological functions.
IgA autoreactivity: a feature common to inflammatory bowel and connective tissue diseases
Authors: KAZEMI-SHIRAZI L , GASCHE C H , NATTER S , GANGL A , SMOLEN J , SPITZAUER S , VALENT P , KRAFT D , VALENTA R
Published: March 2003

The immunopathogenic mechanisms in inflammatory bowel disease (IBD) are not yet fully established. The aim of this study was to determine the profile and magnitude of IgA and IgG autoantibodies in IBD patients. The autoantigen profile defined by IgA and IgG antibodies from 24 IBD (14 Crohn's disease CD], 10 ulcerative colitis UC]), three coeliac, 12 connective tissue disease (CTD) patients and 10 healthy individuals was studied in human cellular extracts by Western blotting. The magnitude of the IgA and IgG1-4 subclass responses was measured by ELISA. IBD patients could not be distinguished from healthy individuals on the basis of IgG autoantibodies to Western blotted proteins. IgG subclass analysis indicated no clear bias towards Th1 or Th2 immune responses in IBD or CTD. In accordance with previous work, we found that IgA autoreactivity was strongest in coeliac disease patients. Unexpectedly, IBD as well as CTD patients exhibited strong IgA autoantibody reactivities to components of similar molecular weights (16–80 kD) in intestinal and non-intestinal epithelial cell lines. Our data indicate immunopathogenic similarities between IBD and CTD.
Atypical X-linked SCID phenotype associated with growth hormone hyporesponsiveness
Authors: URSINI M V , GAETANIELLO L , AMBROSIO R , MATRECANO E , APICELLA A J , SALERNO M C , PIGNATA C
Published: March 2003

Severe combined immunodeficiency (SCID) is a heterogeneous group of disorders characterized by defect of T- and B-cell immunity. In many cases of autosomal recessive SCID, thus far described, the molecular alteration involves genes encoding for molecules that participate in the signal transduction. We report on a patient affected by a combined immunodeficiency, characterized by severe T-cell functional impairment, in spite of a close to normal number of circulating mature type T and B cells. NK cells were absent. Associated with the immunodeficiency, this patient also showed short stature characterized by very low growth velocity, delayed bone age and absence of increase of the plasma levels of Insulin growth factor-I (IGF-I) after growth hormone (GH) in vivo stimulation indicating peripheral hyporesponsiveness to GH. Evaluation of the protein tyrosine phosphorylation events occurring following either T-cell receptor (TCR) or GH receptor (GHR) triggering revealed striking abnormalities. No molecular alteration of GHR gene was found, thus suggesting the presence of postreceptorial blockage. Mutational screening and expression analysis failed to reveal any molecular alteration of JAK2 and STAT 5 A/B genes thus ruling out the involvement of these genes in the pathogenesis of this form of SCID. Mutational analysis of IL2Rγ chain gene revealed the presence of a L183S missense mutation, thus indicating an atypical and a more complex clinical presentation of this X-linked form of SCID. At our knowledge, this is the first report on the GH hyporesponsiveness in this disease.
Cellular immune responses against hepatitis C virus: the evidence base 2002
Authors: WARD S , LAUER G , ISBA R , WALKER B , KLENERMAN P
Published: March 2003

Hepatitis C virus (HCV) is an RNA virus which is estimated to persistently infect about 170 million people worldwide. After acute infection, there is an initial period during which long-term outcome is decided. There is strong evidence that the cellular immune responses, involving both CD4+ and CD8+ T lymphocytes, are involved at this stage and it is their effectiveness which determines outcome. What is not understood is what determines their effectiveness. The most important component of this is likely to be some aspect of epitope selection, itself dictated by host MHC. Thus, to understand host immunity to HCV, we need to have a detailed understanding of the peptides involved in T lymphocyte responses. In this review, we discuss the peptide epitopes that have been identified so far, and their potential significance. We relate this to a scheme of host defence which may be useful for understanding natural and vaccine-induced immunity.
Regulation ofα1-proteinase inhibitor release by proinflammatory cytokines in human intestinal epithelial cells
Authors: FAUST D , RASCHKE K , HORMANN S , MILOVIC V , STEIN J
Published: March 2003

α1-Proteinase inhibitor (α1-PI) is the main serine proteinase inhibitor in human plasma. Apart from its synthesis in the liver, this anti-inflammatory protein is also synthesized by and excreted from human intestinal epithelial cells. Antiinflammatory actions of α1-PI are thought to be of relevance in the pathogenesis of inflammatory bowel disease. To investigate the role of macrophage-derived cytokines on α1-PI secretion from intestinal epithelial cells, we cultured Caco-2 cells until differentiation (14 days in culture) on permeable filter supports. Monolayers of differentiated Caco-2 cells were then co-cultured with human peritoneal macrophages, grown on plastic in the basolateral chamber. Under these conditions, α1-PI secretion from Caco-2 cells was enhanced by 45%, probably by a direct action of macrophage-derived cytokines on Caco-2 cells. To extend this observation further, we treated differentiated Caco-2 cells with macrophage-derived proinflammatory cytokines (IL-1β, IL-8, TNF-α), as well as with lymphocyte-derived cytokines IL-2, IL-6 and IFN-γ. As early as after 24h treatment, IL-2 and IL-8 induced a significant and dose-dependent increase of α-1-PI secretion into cell culture medium; this effect was completely reversed after immunoneutralization by the antibodies against IL-2 and IL-8 α1-PI secretion was only slightly decreased after treatment with IFN-γ, while IL-1β, IL-6 and TNF-α had no effect. α1-PI secretion correlated well with the expression of this protein in differentiated Caco-2 cells after cytokine treatment, as confirmed by Western blot. Our data imply that, in vitro, α1-PI secretion in enterocyte-like Caco-2 cells is up-regulated by IL-2 and IL-8. Our results suggest that both lymphocyte- and macrophage-derived cytokines regulate secretion of the anti-inflammatory protein α1-PI in intestinal epithelial cells.
Takes your breath away – the immunology of allergic alveolitis
Authors: MCSHARRY C , ANDERSON K , BOURKE S J , BOYD G
Published: March 2003

Extrinsic allergic alveolitis (synonym: hypersensitivity pneumonitis) is caused by inhaling antigenic aerosols which induce hypersensitivity responses in susceptible individuals. It is an interstitial inflammatory disease affecting the distal, gas-exchanging parts of the lung, in contrast to allergic asthma where the inflammation is more proximal, affecting the conducting airways. The aims of this review are to describe current concepts of the immunology of this model of lung inflammation, to describe some of the constitutional and environmental characteristics which affect disease susceptibility and development, and to describe topics for prospective study.
Normal and SV40 transfected human peritoneal mesothelial cells produce IL-6 and IL-8 :  implication for gynaecological disease
Authors: ZHANG X Y , GUCKIAN M , NASIRI N , LOVELL P A , DALGLEISH A G , BARTON D P J
Published: March 2003

High levels of interleukin-6 (IL-6) and interleukin-8 (IL-8) have been demonstrated in the peritoneal fluid of benign and malignant gynaecological disease. Peritoneal monocytes and macrophages, endometrial cells, endometrial and peritoneal stromal cells and tumour cells produce these cytokines in vitro. To investigate whether normal human peritoneal mesothelial cells (HPMC) produce IL-6 and IL-8, HPMC were isolated from omental biopsies. Primary HPMC (P-HPMC) were transfected with pSV3-neo encoding SV40 large T antigen (T-HPMC) to generate sufficient cells. T-HPMC preserved the characteristics of P-HPMC as assessed by phase contrast microscopy, electron microscopy, immunocytochemistry and flow cytometry (FACS) analysis. T-HPMC retained a stable phenotype up to passage 14–19, whereas P-HPMC proliferated poorly and became senescent by passage 4–6. T-HPMC and P-HPMC constitutively expressed IL-6 and IL-8 at both protein and mRNA level. IL-6 and IL-8 production was stimulated by recombinant human interleukin-1β (hIL-1β) or human tumour necrosis factor-α (hTNF-α) alone in a dose-dependent manner. Moreover, hIL-1β or hTNF-α up-regulated IL-6 and IL-8 gene expression as determined by competitive PCR. In contrast, human interferon-γ (hIFN-γ) or lipopolysaccharide (LPS) showed no effect. These data indicate that (1) T-HPMC lines mimic the morphological and functional features of P-HPMC, (2) P-HPMC and T-HPMC constituitively produce IL-6 and IL-8, which is enhanced by hIL-1β and hTNF-α and (3) HPMC in vivo may participate in the pathogenesis of benign and malignant gynaecological disease.
Profiles of cell-to-cell interaction ofMycobacterium intracellulare-induced immunosuppressive macrophages with target T cells in terms of suppressor signal transmission
Authors: OGASAWARA K , TOMIOKA H , SHIMIZU T , SANO C , KAWAUCHI H , SATO K
Published: March 2003

Previously, we have found that immunosuppressive macrophages (Mφs) induced by Mycobacterium intracellulare-infection (MI-Mφs) required cell contact with target T cells to express their suppressor activity against concanavalin A (Con A)-induced T cell mitogenesis. In this study, we examined the profiles of cell-to-cell interaction of MI-Mφs with target T cells. First, MI-Mφs displayed suppressor activity in an H-2 allele-unrestricted manner, indicating that MHC molecules are not required for cell contact. The suppressor activity of MI-Mφs was reduced markedly by paraformaldehyde fixation or treatment with cytochalasin B or colchicine, indicating that vital membrane functions are required for their suppressor activity. Secondly, the suppressor activity of MI-Mφs was independent of cell-to-cell interaction via CD40 ligand/CD40 and Mφ-derived indoleamine 2,3-dioxygenase, which causes rapid degradation of tryptophan in T cells. Thirdly, precultivation of splenocytes with MI-Mφs, allowing cell-to-cell contact, reduced Con A- or anti-CD3 antibody-induced mitogenesis but not phorbol myristate acetate/calcium ionophore A23187-elicited proliferation of T cells. In addition, co-cultivation of T cells with MI-Mφs caused marked changes in profiles of the tyrosine phosphorylation of 33 kDa, 34 kDa and 35-kDa proteins and, moreover, the activation of protein kinase C and its translocation to the cell membrane. It thus appears that suppressor signals of MI-Mφs, which are transmitted to the target T cells via cell contact, principally cross-talk with the early signalling events before the activation of PKC and/or intracellular calcium mobilization.
Inhibition of human natural killer cell activity by cereulide, an emetic toxin fromBacillus cereus
Authors: PAANANEN A , MIKKOLA R , SARENEVA T , MATIKAINEN S , HESS M , ANDERSSON M , JULKUNEN I , SALKINOJA-SALONEN M S , TIMONEN T
Published: March 2003

The lipophilic toxin, cereulide, emitted by emetic food poisoning causing strains of Bacillus cereus, is a powerful mitochondria toxin. It is highly lipophilic and rapidly absorbed from the gut into the bloodstream. We tested how this toxin influences natural killer (NK) cells, which are important effectors in defence against infections and malignancy. Cereulide inhibited cytotoxicity and cytokine production of natural killer cells, caused swelling of natural killer cell mitochondria, and eventually induced natural killer cell apoptosis. The suppressive effect on cytotoxicity was fast and toxic concentration low, 20–30 μg/l. As the emesis causing concentration of cereulide is around 10 μg/kg of total body mass, our results suggest that emesis causing or even lower doses of cereulide may also have a systemic natural killer cell suppressive effect.
Activation of pulmonary T cells in corticosteroid-resistant and -sensitive interstitial pneumonitis in dermatomyositis/polymyositis
Authors: KURASAWA K , NAWATA Y , TAKABAYASHI K , KUMANO K , KITA Y , TAKIGUCHI Y , KURIYAMA T , SUEISHI M , SAITO Y , IWAMOTO I
Published: March 2003

To study the activation states and cytokine profiles of pulmonary T cells in corticosteroid-resistant and corticosteroid-sensitive interstitial pneumonitis (IP) in dermatomyositis (DM)/polymyositis (PM), we examined the activation markers and cytokine profiles of T cells in bronchoalveolar lavage fluids (BALF) from patients with IP in DM/PM before prednisolone therapy and then compared the activation states of T cells according to the therapeutic response of IP to prednisolone therapy. CD25+ CD4+ T cells in BALF were significantly increased in both corticosteroid-resistant and corticosteroid-sensitive IP in DM/PM as compared with those in controls without IP. Furthermore, CD25+ CD4+ T cells in BALF were significantly more increased in corticosteroid-resistant IP than those in cortico teroid- sensitive IP. Moreover, CD25+ CD8+ T cells in BALF were significantly increased only in corticosteroid-resistant IP, but not in corticosteroid-sensitive IP or controls without IP. IFN-γ mRNA was detected in BALF T cells in corticosteroid-resistant and corticosteroid-sensitive IP but not in controls without IP, whereas IL-4 mRNA was virtually undetected in BALF T cells in both the IP groups. However, there were no significant differences in CD4/CD8 ratio of BALF T cells, HLA-DR+ BALF T cells or CD25+ and HLA-DR+ peripheral blood T cells between the two IP groups. These results indicate that activated Th1-type pulmonary T cells play an important role in the development of corticosteroid- resistant IP in DM/PM and that the increase in CD25+ CD8+ T cells in BALF is a useful indicator for corticosteroid-resistant IP in DM/PM and hence may be an indicator for early use of cyclosporin.
The strength of the OVA-induced airway inflammation in rats is strain dependent
Authors: HYLKEMA M N , HOEKSTRA M O , LUINGE M , TIMENS W
Published: March 2003

To examine the influence of genetics on the OVA-induced allergic inflammatory response in lungs we compared rats that are genetically Th2-predisposed (Brown Norway, inbred) or not genetically predisposed (Sprague Dawley, outbred). Rats were sensitized with ovalbumin (OVA) and challenged four weeks later with OVA aerosol. Eighteen hours after challenge, lung tissue was studied for evaluation of numbers of eosinophils, neutrophils, macrophages and mast cells, as well as for expression of P-selectin, E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells. From a separate portion of the pulmonary tissue, leucocytes were isolated to analyse numbers of IFNγ and IL-4 producing cells (ELISPOT assay) and frequencies of T-cell subsets and B cells. We found increased numbers of eosinophils and neutrophils in the lung, an increased number of IL-4 producing cells in lung cell isolates and increased levels of serum (OVA- specific)-IgE in both rat strains. In addition, expression of E-selectin and ICAM-1 was up regulated in both rat strains whereas expression of VCAM-1 was only up regulated in the BN rat. Although the ‘allergic’ Th2 response to OVA was detectable in both rat strains, it was more pronounced in the BN rat than in the SD rat. However, the SD rat, which is not predisposed to respond in either a Th2 or Th1-like way, appeared capable of mounting an allergic response to OVA. This suggests that other factors than genetic contribute to allergic disease.
Thalidomide and its analogues have distinct and opposing effects on TNF-αand TNFR2 during co-stimulation of both CD4+ and CD8+ T cells
Authors: MARRIOTT J B , CLARKE I A , DREDGE K , MULLER G , STIRLING D , DALGLEISH A G
Published: March 2003

Thalidomide (Thd) is clinically useful in a number of conditions where its efficacy is probably related to its anti-TNF-α activity. More recently, Thd has also been shown to co-stimulate T cells and second generation co-stimulatory (IMiD™) analogues are currently being assessed in the treatment of cancer patients. However, in contrast to their known suppressive effects during inflammatory stimuli, the effects of Thd/IMiDs on TNF-α and TNF receptors (TNFRs) during T cell co-stimulation are not known. We sought to determine the effect of Thd, two clinically relevant IMiDs (CC-4047, ACTIMID™ and CC-5013, REVIMID™) and a non-stimulatory SelCID analogue (CC-3052) on TNF-α production and on the expression and shedding of TNFRs during co-stimulation. We found that co-stimulation of PBMC with Thd/IMiDs, but not CC-3052, prevented αCD3-induced T cell surface expression of TNFR2 and thereby reduced soluble TNFR2 (sTNFR2) levels. However, there was no effect on total (surface/intracellular) TNFR2 protein expression, suggesting inhibition of trafficking to the cell membrane. The extent of co-stimulation by Thd/IMiDs (assessed by CD69/CD25 expression and IL-2/sIL-2Rα production) was similar for CD4+ and CD8+ T lymphocytes and correlated with TNFR2 inhibition. Co-stimulation, but not the early inhibitory effect on TNFR2, was IL-2-dependent and led to increased TNF-α production by both CD4+ and CD8+ T lymphocytes. The clinical relevance of this observation was confirmed by the elevation of serum TNF-α during REVIMID™ treatment of patients with advanced cancer. Together, these results suggest a possible role for TNF-mediated events during co-stimulation and contrast with the TNF inhibitory effects of Thd and its analogues during inflammatory stimuli.
Pimecrolimus inhibits up-regulation of OX40 and synthesis of inflammatory cytokines upon secondary T cell activation by allogeneic dendritic cells
Authors: KALTHOFF F S , CHUNG J , STUETZ A
Published: March 2003

Pimecrolimus is a new non-steroidal inhibitor of T cell and mast cell activation. In the present study, we compared the potency of pimecrolimus and cyclosporin A (CyA) to inhibit cytokine synthesis of alloantigen-primed T cells and the expression of CD134 (OX40), an inducible co-receptor molecule thought to be critical for the survival and expansion of inflammation-mediating T cells. To mimic the physiological situation of recurrent antigenic stimulation, we have used dendritic cells (DC) as stimulators of purified CD4+ T cells in the primary and secondary allogeneic mixed lymphocyte culture (allo-MLC). Pimecrolimus inhibited surface expression of OX40 and prevented the up-regulation of CD25 and CD54 with a 10-fold higher potency compared to CyA. Similarly, 50% inhibition of allo-DC-mediated T cell proliferation by pimecrolimus was obtained at 0·55 nm, compared to about 12 nm for CyA. Furthermore, pimecrolimus blocked the increase of OX40 on primed T cells restimulated on day 10 in secondary allo-MLC. Allo-DC-primed T cells showed a restricted cytokine profile characterized by the production of TNF-α, IFN-γ and IL-2 but low to undetectable levels of IL-4 and IL-10. The synthesis of TNF-α and IFN-γ and the up-regulation of OX40 on T cells after secondary allogeneic stimulation were almost entirely blocked by 10 nm pimecrolimus. Taken together, pimecrolimus inhibits T cell proliferation and Th1 cytokine synthesis and also prevents the up-regulation of the OX40 co-receptor on primed T cells indicating its potential in the therapy of chronic inflammation and autoimmunity.
The level of IgA antibodies to human umbilical vein endothelial cells can be enhanced by TNF-α treatment in children with Henoch–Schönlein purpura
Authors: YANG Y-H , WANG S J , CHUANG Y-H , LIN Y-T , CHIANG B-L
Published: March 2003

Anti-endothelial cell antibodies (AECA) have been found to play an important role in many vascular disorders. In order to determine the presence of AECA in children with Henoch–Schönlein purpura (HSP), and to elucidate the pathogenic and clinical value of their measurement in this disease, AECA were detected by immunofluorescence staining and a human umbilical vein endothelial cell (HUVEC)-based enzyme-linked immunosorbent assay (ELISA) in 20 children with HSP, 10 children with juvenile rheumatoid arthritis (JRA) without vasculitis and 10 normal healthy children. Antibodies against another endothelial cells, human dermal microvascular endothelial cells (HMVEC-d) were also detected by cell-based ELISA. In some experiments, we compared the binding activity of antibodies to HUVEC with and without tumour necrosis factor-α (TNF-α) or interleukin-1 (IL-1) pretreatment. Patients with acute onset of HSP had higher serum levels of IgA antibodies, both against HUVEC and against HMVEC-d, than healthy controls (P = 0·001, P = 0·008, respectively). Forty-five per cent of patients had positive IgA AECA to HUVEC, and 35% had positive IgA AECA to HMVEC-d. The titres of IgA antibodies to HUVEC paralleled the disease activity. After TNF-α treatment, the values of IgA AECA to HUVEC in HSP patients were significantly increased (P = 0·02). For IgG and IgM AECA, there was no difference between HSP patients and controls (P = 0·51, P = 0·91). Ten JRA children without vasculitis had no detectable IgG, IgM or IgA AECA activity. The results of this study showed that children with HSP had IgA AECA, which were enhanced by TNF-α treatment. Although the role of these antibodies is not clear, IgA AECA provide another immunological clue for the understanding of HSP.
Alteration of Fas and Fas ligand expression during human visceral leishmaniasis
Authors: EIDSMO L , WOLDAY D , BERHE N , SABRI F , Satti I , El Hassan A M , SUNDAR S , CHIODI F , Akuffo H
Published: March 2003

Several studies in murine systems have suggested a role of apoptosis in the pathogenesis of leishmaniasis. However, the role of apoptosis in visceral leishmaniasis in man has not been explored. In this study, we show that patients with visceral leishmaniasis demonstrate significant dysregulation of Fas and Fas ligand. Levels of soluble Fas (sFas) and soluble Fas ligand (sFasL) were elevated in plasma of patients with active visceral leishmaniasis (VL) and individuals co-infected with VL-HIV-1 compared to healthy controls. The levels of sFas and sFasL were normalized 6 months after successful treatment. In VL patients, the expression of membrane bound Fas, and to a lower extent FasL, were up-regulated on Leishmania donovani-infected spleen cells, the site of parasite multiplication. Expression of Fas and FasL on peripheral blood mononuclear cells was within normal range, probably reflecting that the blood is not a normal site of L. donovani infection. Furthermore, this is suggested by the finding that in vitro infection of macrophages with L. donovani up-regulated Fas expression on the surface of infected cells and enhanced the levels of sFasL in supernatants from infected cultures. How this dysregulation may affect the pathogenesis of human visceral leishmaniasis is discussed.
The role of anti-endothelial cell antibodies in Kawasaki disease –in vitroandin vivostudies
Authors: GRUNEBAUM E , BLANK M , COHEN S , AFEK A , KOPOLOVIC J , MERONI P L , YOUINOU P , SHOENFELD Y
Published: March 2003

Kawasaki disease (KD) is a systemic vasculitis with cardiac and noncardiac complications. Anti-­endothelial cell antibodies (AECA) are found among many patients with KD. The aim of this study was to investigate the pathogenic role of AECA in KD using in vitro and in vivo experimental models. F(ab)2 fragments of IgG-AECA and IgM-AECA were affinity purified from a patient with active KD. Their endothelial binding and ability to induce a pro-adhesive and a pro-inflammatory phenotype were evaluated in vitro. Twenty Balb/C mice were immunized with KD-AECA or with control Ig (N-Ig) to induce AECA in a murine model by the idiotypic manipulation method. Both KD-AECA isotypes bind significantly to human umbilical vein endothelial cell (HUVEC) compared to N-Ig. The in vitro activity was demonstrated by the antibodies ability to activate endothelial cells resulting in increased IL-6 secretion, adhesion molecule expression and monocytic cell line (U937) adherence to HUVEC. Five of the mice that received KD-AECA developed murine AECA after 3 months. None of the mice that received N-Ig produced AECA. The murine AECA increased monocyte adhesion to EC in vitro, similarly to the AECA used for immunization. Furthermore, all the mice that developed AECA had proteinuria and IgG deposition in the renal mesangium. No histological or immunofluorescence evidence of cardiac vasculitis could be detected. AECA might play a role in the emergence of some of KD manifestations.
The role of somatic mutation in determining the affinity of anti-DNA antibodies
Authors: BEHRENDT M , PARTRIDGE L J , GRIFFITHS B , GOODFIELD M , SNAITH M , LINDSEY N J
Published: March 2003

Combinatorial antibody libraries were constructed from the spleen of a patient with concomitant systemic lupus erythematosus and idiopathic thrombocytopenia. Following selection of the libraries with DNA, a panel of 15 anti-DNA Fabs was isolated. Sequence analysis of these antibodies coupled with measurements of their affinities for ss- and dsDNA were used to investigate the role of somatic mutation in affinity maturation of the anti-DNA response. Examination of the germline genes used by these Fabs supports previous studies that suggest there is no restriction of the gene usage in the anti-DNA response. However, data are presented indicating that VH3 genes and the A27 V paired with the J1 may be over-expressed in the anti-DNA repertoire. Analysis of the role of somatic mutation in increasing affinity for DNA indicates that affinity maturation has occurred and suggests that the CDR1 and CDR2 of the heavy chain are of importance in this process.
Xenobiotic metal-induced autoimmunity: mercury and silver differentially induce antinucleolar autoantibody production in susceptible H-2s, H-2q and H-2f mice
Authors: HANSSON M , ABEDI-VALUGERDI M
Published: March 2003

Xenobiotic-metals such as mercury (Hg) and silver (Ag) induce an H-2 linked antinucleolar autoantibody (ANolA) production in susceptible mice. The mechanism for induction of ANolA synthesis is not well understood. However, it has been suggested that both metals interact with nucleolar proteins and reveal cryptic self-peptides to nontolerant autoreactive T cells, which in turn stimulate specific autoreactive B cells. In this study, we considered this suggestion and asked if mercury and silver display, if not identical, similar cryptic self-peptides, they would induce comparable ANolA responses in H-2 susceptible mice. We analysed the development of ANolA production in mercury- and/or silver-treated mice of H-2s, H-2q and H-2f genotypes. We found that while mercury stimulated ANolA synthesis in all strains tested, silver induced ANolA responses of lower magnitudes in only H-2s and H-2q mice, but not in H-2f mice. Resistance to silver in H-2f mice was independent of the dosage/time-period of silver-treatment and non-H-2 genes. Further studies showed that F1 hybrid crosses between silver-susceptible A.SW (H-2s) and -resistant A.CA (H-2f) mice were resistant to silver, but not mercury with regard to ANolA production. Additionally, the magnitudes of mercury-induced ANolA responses in the F1 hybrids were lower than those of their parental strains. The above differential ANolA responses to mercury and silver can be explained by various factors, including the different display of nucleolar cryptic peptides by these xenobiotics, determinant capture and coexistence of different MHC molecules. Our findings also suggest that the ability of a xenobiotic metal merely to create cryptic self-peptides may not be sufficient for the induction of an ANolA response.