IL-10 producing regulatory and helper T-cells in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a highly heterogeneous autoimmune disease characterised by the production of pathogenic autoantibodies against nuclear self-antigens. The anti-inflammatory and tolerogenic cytokine Interleukin-10 appears to play a paradoxical pathogenic role in SLE and is therefore currently therapeutically targeted in clinical trials. It is generally assumed that the pathogenic effect of IL-10 in SLE is due to its growth and differentiation factor activity on autoreactive B-cells, but effects on other cells might also play a role. To date, a unique cellular source of pathogenic IL-10 in SLE has not been identified. In this review, we focus on the contribution of different CD4⁺T-cell subsets to IL-10 and autoantibody production in SLE. In particular, we discuss that IL-10 produced by different subsets of adaptive regulatory T-cells, follicular helper T-cells and extra-follicular B-helper T-cells is likely to have different effects on autoreactive B-cell responses. A better understanding of the role of IL-10 in B-cell responses and lupus would allow to identify the most promising therapies for individual SLE patients in the future.

Impact of in utero environment on the offspring of lupus patients

The number of patients affected by systemic lupus erythematosus (SLE) that decide to have children has greatly increased probably because of recent improvements in the diagnosis and management of the disease. This has stimulated our interest in defining the outcome of children, focusing both on neonatal problems and long term development. SLE patients still carry a risk of pregnancy loss. However, due to careful monitoring and treatment by a multidisciplinary team, the number of losses has dramatically decreased, but an increased number of preterm deliveries is still a problem. Neonatal lupus is linked to the presence of anti-Ro/SS-A and anti-La/SS-B antibodies in the mother, although other factors probably of fetal origin are important. Neonatal lupus is a complex condition whose most serious manifestation is the congenital heart block (CHB). Usually, children with complete CHB need permanent pacing, but apparently do not have neuropsychological problems. Studies focusing on the neuropsychological development of SLE offspring show an increased number of learning disabilities in children with normal intelligence levels. Fetal consequence of maternal treatment need to be considered choosing non teratogenic drugs, but the withdrawal of medications just because the patient is pregnant should be avoided to avoid SLE flares.

First steps in the standardization of immunoglobulin IgG myeloperoxidase-anti-neutrophil cytoplasmic antibody measurements

The standardization of immunoassays for immunoglobulin (Ig)G myeloperoxidase-anti-neutrophil cytoplasmic antibodies (MPO-ANCA) could contribute to a more accurate diagnosis and follow-up of small vessels-associated vasculitis, a systemic autoimmune disorder that leads to necrosis of blood vessel walls. Despite significant efforts by different groups, the level of comparability of results from commercially available immunoassays used for IgG MPO-ANCA detection is still poor. Therefore, the potential for improvement using reference materials was assessed. The evaluation of a set of 30 patient samples with 11 assays showed that differences between assays result in different interpretations for individual patients. Only 10 of 30 patient samples had the same clinical interpretation among 11 assays applying the cut-off values provided by each respective manufacturer. The correlation between results from 13 different assays was assessed in a pairwise manner. The correlation between results from patient samples was systematically very good for combinations of seven of those assays. The correlation of results ranged from reasonable to good for combinations with four other assays, therefore it should be possible to improve the comparability of results using a commutable reference material for calibration. Feasibility studies were conducted in order to find a reference material format most suitable for a calibrator. Two sets of candidate reference materials were produced from different raw materials, and assessed according to their suitability. A final format was selected, and a candidate reference material was produced.

Ferritin in the antiphospholipid syndrome and its catastrophic variant (cAPS)

BACKGROUND

Ferritin is an iron storage protein considered also as an acute phase reactant with high levels in various inflammatory conditions. Recently, a plausible role for ferritin in the pathogenesis of immune-mediated and especially autoimmune diseases has been suggested. However, the link between ferritin and the antiphospholipid syndrome (APS) has been rarely explored. Therefore, in the current study we evaluated ferritin levels and their correlation to clinical and serological manifestations in patients with APS. We further analyzed ferritin levels among patients with the catastrophic variant of APS (cAPS).

METHODS

Ferritin levels were determined in serum samples of 176 APS patients and 98 matched healthy controls according to age and sex (LIAISON, DiaSorin, Italy). APS samples were further analyzed for antiphospholipid (anti-cardiolipin, anti- beta-2-glycoprotein, lupus anticoagulant) and anti-infectious antibodies (CMV, EBV, rubella, toxoplasma, HBV) (LIAISON, DiaSorin, Italy). Clinical, serological and demographic manifestations were recorded. An additional analysis of ferritin levels among 14 patients with cAPS was performed.

RESULTS

Hyperferritinemia was present in 9% vs. 0% of APS patients and controls, respectively (p < 0.001). Among patients with APS, ferritin levels correlated with venous thrombosis, cardiac, neurological, and hematological manifestations and the presence of anti-CMV-IgM antibodies. Hyperferritinemia was present in 71% of cAPS patients, and ferritin levels among this subgroup were significantly higher compared with APS-non-cAPS patients (816 ± 847 ng/ml vs. 120 ± 230 ng/ml, p < 0.001).

CONCLUSIONS

Herein, we found that hyperferritinemia correlates with the presence of APS, its clinical manifestations and specifically with the catastrophic variant of this disease. Hyperferritinemia was also linked with anti-CMV antibodies among patients with APS. These associations allude to a pathogenic role of ferritin in the pathogenesis of APS, and the plausible role of ferritin as a marker of ensuing cAPS, although further studies are needed to elucidate these associations.

The immunobiology of apotransferrin in type 1 diabetes

The transferrin (Tf) family of iron binding proteins includes important endogenous modulators of the immune function that may modulate autoimmune diseases. To define more clearly the role of apotransferrin (apoTf) in type 1 diabetes we determined the impact of this protein on type 1 diabetes as investigated in islet cells, animal models and patient sera. First, we demonstrated that recombinant apoTf counteracts the cytokine-induced death of murine pancreatic islet cells. Secondly, human apoTf administration favourably influences the course of type 1 diabetes in animal models, resulting in protection against disease development that was associated with reduction of insulitis and reduced levels of proinflammatory cytokines. Finally, we confirmed that patients with newly diagnosed type 1 diabetes manifest significantly lower apoTf serum levels compared to healthy controls and patients with long-lasting disease. In conclusion, our data suggest the apoTf pivotal role in the perpetuation of type 1 diabetes pathology.

Antiphospholipid antibody profile: implications for the evaluation and management of patients

According to the classification criteria of antiphospholipid syndrome, lupus anticoagulant, anticardiolipin and anti-β2 glycoprotein I antibody assays are independent risk factors for the occurrence of vascular thrombosis and pregnancy loss. However, it is generally accepted that patients carrying multiple positivity have more a severe disease and higher recurrence rate despite treatment. On the other hand, the diagnostic value of a positive result in one only assay is more controversial, particularly in the presence of clinical manifestations such as deep vein thrombosis or early miscarriages, which are rather common in the general population. In this review we speculate on current and future strategies to interpret different antiphospholipid antibody profiles in the clinical practice. Lupus (2010) 19, 432—435.

Variable effects of cyclophosphamide in rodent models of experimental allergic encephalomyelitis

In this study, we have evaluated the effects of cyclophosphamide on the development of experimental allergic encephalomyelitis (EAE) in four EAE rodent models: monophasic EAE in Lewis rats, protracted relapsing (PR)-EAE in DA rats, myelin oligodendrocyte protein (MOG)-induced EAE in C57Bl/6 mice and proteolipid protein (PLP)-induced EAE in Swiss/Jackson Laboratory (SJL) mice. Cyclophosphamide, administered either prophylactically or therapeutically, suppressed most strongly the clinical symptoms of PR-EAE in DA rats. Treated rats in this group also exhibited the lowest degree of inflammatory infiltration of the spinal cord, as well as the lowest levels of nuclear factor kappa B, interleukin-12 and interferon-gamma. Cyclophosphamide prophylactically, but not therapeutically, also delayed significantly the onset of EAE in Lewis rats. In contrast, regardless of the treatment regimen used, was unable to influence the clinical course of EAE in either MOG-induced EAE in C57Bl/6 mice or PLP-induced EAE in SJL mice. This heterogeneous pharmacological response to cyclophosphamide suggests that significant immunopathogenic differences exist among these EAE rodent models that must be considered when designing preclinical studies. In addition, the effectiveness of cyclophosphamide in dark Agouti (DA) rats with PR-EAE suggests that this may be a particularly useful model for studying novel therapeutic approaches for refractory and rapidly worsening multiple sclerosis in human patients.

Update on safety during pregnancy of biological agents and some immunosuppressive anti-rheumatic drugs

A consensus paper concerning the interaction of anti-rheumatic drugs and reproduction was published in 2006, representing data collected during the year 2004 and 2005. Because of an increasing use of biological agents in women of fertile age, the information was updated for the years 2006 and 2007. Experts disagree whether TNF-inhibitors should be stopped as soon as pregnancy is recognized or may be continued throughout pregnancy. Pregnancy experience with abatacept and rituximab is still too limited to prove their safety for the developing fetus. They must be withdrawn before a planned pregnancy. LEF has not been proven to be a human teratogen. Registries of transplant recipients have shown that cyclosporin (CsA) and tacrolimus do not increase the rate of congenital anomalies, whereas mycophenolate mofetil (MMF) clearly carries a risk for congenital anomalies. Prophylactic withdrawal of drugs before pregnancy is mandatory for abatacept, rituximab, LEF and MMF. Data remain insufficient for gonadal toxicity of immunosuppressive drugs in men and for excretion of these drugs in human breast milk.

Antiprothrombin antibodies: a comparative analysis of homemade and commercial methods. A collaborative study by the Forum Interdisciplinare per la Ricerca nelle Malattie Autoimmuni (FIRMA)

OBJECTIVE

Prothrombin (PT) is a target for antibodies with lupus anticoagulant (LA) activity, suggesting the possible application of anti-prothrombin antibody (aPT) assays in patients with antiphospholipid syndrome (APS). Different methods - both homemade and commercial - for the detection of aPT are available, but they seem to produce conflicting results. The purpose of this study was to compare the performance of different assays on a set of well-characterized serum samples.

PATIENTS AND METHODS

Sera were gathered from 4 FIRMA institutions, and distributed to 15 participating centres. Forty-five samples were from patients positive for LA and/or anticardiolipin antibodies (aCL) with or without APS, and 15 were from rheumatoid arthritis (RA) patients negative for antiphospholipid antibodies. The samples were evaluated for IgG and IgM antibodies using a homemade direct aPT assay (method 1), a homemade phosphatidylserine-dependent aPT assay (aPS/PT, method 2), and two different commercial kits (methods 3 and 4). In addition, a commercial kit for the detection of IgG-A-M aPT (method 5) was used.

RESULTS

Inter-laboratory results for the 5 methods were not always comparable when different methods were used. Good inter-assay concordance was found for IgG antibodies evaluated using methods 1, 3, and 4 (Cohen k > 0.4), while the IgM results were discordant between assays. In patients with thrombosis and pregnancy losses, method 5 performed better than the others.

CONCLUSION

While aPT and aPS/PT assays could be of interest from a clinical perspective, their routine performance cannot yet be recommended because of problems connected with the reproducibility and interpretation of the results.

Mechanisms of immune-mediated skin diseases: an overview

The skin is a frequent site of pathological immune responses that can take place in the dermal and/or the epidermal compartments.These immunopathological reactions often occur towards innocuous antigens and may be the result of T cell-dependent and/or autoantibody dependent mechanisms. Defective immune regulation is increasingly recognized as very relevant in many skin and systemic immune-mediated disorders. In some instances (e.g., psoriasis and atopic dermatitis) genetic predisposition can affect also the capacity of keratinocytes to initiate or perpetuate inflammatory responses. A more precise understanding of the molecular and cellular mechanisms underlying each disorder may allow the identification of novel targets for more effective therapeutic strategies.

[Quality and efficiency of the Health Service in the Italian Region of Lombardy]

The Regional Law No. 31 of 1997 has revised the Lombardy Health Service as a whole, separating "providers", credited Public and Private Health Institutions, from "purchasers", Local Health Agencies. To this purpose, the improvement of the quality of assistance has been enhanced through an accreditation process aimed at implementing second level regional requirements considered as being necessary for carrying out effective treatment and meeting patient needs. Training, implementation and evaluation of quality service within Health Institutions have been carried out with the assistance of the Regional Observatory on the Quality of Health Service, which helped to identify initial intervention areas, define process indicators, activities and outcomes and verify patient satisfaction, all this to improve performance, reduce risks and control costs. To fully develop the Institutions in the accreditation process, the complex and difficult aspect of health care quality has been more extensively and deeply dealt with by adopting an "Excellence accreditation" model in cooperation with the Joint Commission International Accreditation and by experimenting with Professional accreditation supported by Scientific Societies to further contribute to the development of technical skills and knowledge. The Quality Project carried out so far is based on the integration of various projects, which will be the object of practical interventions by the General Health Direction. All the information and results gathered from this project will be very helpful in finding solutions that will enable all Health Institutions in Lombardy to reach an adequate level of quality.

Anticardiolipin antibody assay: a methodological analysis for a better consensus in routine determinations--a cooperative project of the European Antiphospholipid Forum

Despite the widely recognized practical importance of anticardiolipin (aCL) ELISA, the reliability of this test has been recently discussed. In order to investigate this area on European scale, we sent to 30 experienced centers a questionnaire focusing on the diagnostic procedures applied to patients with antiphospholipid syndrome (APS) and on the detailed protocols used to perform aCL. Anticardiolipin ELISA was found to be the most frequently performed test in patients with suspected APS, but significant difference was shown among the various protocols. The cross-laboratory multiple examination of ten serum samples evaluated independently by the 24 centers pointed out the difficulty in getting comparable results. Therefore a "consensus" protocol was derived from the aCL methods giving the best performance. The materials and reagents necessary to perform the "consensus" method, including, as putative standards, one IgG and one IgM monoclonal antibody (HCAL and EY2C9) were distributed to 19 Centers. The results of one IgG and one IgM aCL high positive sera measured in serial dilutions were compared. A progressive decrease in the variability of the values obtained for a given sample appeared evident when all the laboratories used the same standard, in their own in-house ELISA and even more in the "consensus" ELISA. Our data show that aCL ELISA standardization is necessary in order to obtain comparable results in different laboratories.

Prevention and treatment of lethal murine endotoxemia by the novel immunomodulatory agent MFP-14

Multifunctional protein 14 (MFP-14) is a ubiquitous protein that inhibits the production of tumor necrosis factor alpha (TNF-alpha) and gamma interferon (IFN-gamma), which are involved in the pathogenesis of sepsis. Here, lipopolysaccharide (LPS)-induced lethality in mice was markedly reduced by MFP-14. The treatment also lowered LPS-induced levels of TNF-alpha and IFN-gamma in the blood.

The antiinflammatory cytokine interleukin-13 is not detectable in the circulation of multiple sclerosis patients and is not inducible by interferon-beta1b treatment, that neither modifies its ex vivo secretion from peripheral blood mononuclear cells

Interleukin (IL)-13 is a T-cell derived cytokine closely related to IL-4 that possesses powerful antiinflammatory properties. In this study we have evaluated the blood levels of IL-13 in patients with multiple sclerosis (MS), either with relapsing remitting or secondary chronic progressive (CP) course of the disease, and have also examined the effect of treatment with interferon (IFN)-beta 1b given on alternate days for 10 days both on the serum levels of IL-13 and on the ex vivo secretory capacity of mononuclear cells from MS patients. IL-13 was not detectable in the circulation of MS patients regardless of whether RR MS patients with stable or active disease or those suffering from secondary CP MS were studied. Moreover, circulating levels of IL-13 were not induced by treatment with IFN- beta1b, that was neither capable of modifying the ex vivo IL-13 secretory capacity of peripheral blood mononuclear cells. These data neither anticipate a role for endogenous IL-13 in down-regulating immunoinflammation during MS attacks nor suggest that IFN-betalb treatment exerts its favourable effects on the course of RR MS by augmenting the secretion of this antiinflammatory cytokine.

Murine concanavalin A-induced hepatitis is prevented by interleukin 12 (IL-12) antibody and exacerbated by exogenous IL-12 through an interferon-gamma-dependent mechanism

Concanavalin A (ConA)-induced hepatitis is a cell-mediated immunoinflammatory condition similar to human autoimmune hepatitis. We investigated the role of interleukin 12 (IL-12) in hepatitis induced in NMRI and C57/BL6 mice by a single injection of ConA. Recombinant murine IL-12 administered 24 hours and 1 hour prior to ConA exacerbated both transaminase activities in plasma and histologic signs of hepatitis. These markers of liver injury were significantly reduced by prophylactic, but not therapeutic treatment with anti-IL-12 monoclonal antibody (mAb). The disease-modulatory effects of IL-12 and anti-IL-12 mAb were associated with profound and reverse modifications of a ConA-induced increase in the circulating levels of IL-4, IL-6, interferon gamma (IFN-gamma) and tumor necrosis factor (TNF). Relative to control animals receiving ConA alone, the plasma levels of these cytokines were all augmented in IL-12/ConA-treated mice and diminished in anti-IL-12 mAb/ConA-treated mice. Anti-IFN-gamma mAb also impeded the appearance of IL-12/ConA-induced hepatitis. Thus, IL-12-induced production of IFN-gamma might play a role in mediating the hepatitis-inducing effect of ConA. However, IL-12p40-deficient C57/BL6 mice were as susceptible as wild-type controls to the hepatitis-inducing effect of ConA.

Essential pathogenetic role for interferon (IFN-)gamma in concanavalin A-induced T cell-dependent hepatitis: exacerbation by exogenous IFN-gamma and prevention by IFN-gamma receptor-immunoglobulin fusion protein

We have studied the effects of either exogenously-administered interferon (IFN-)gamma or of a nonimmunogenic mouse IFN-gamma receptor-Immunoglobulin (IFN-gamma R-Ig) fusion protein on the development of Concanavalin (Con)A-induced hepatitis in NMRI mice. PBS-treated control mice injected with 20 mg/kg ConA developed classical serological and histological signs of hepatitis with elevation of transaminases in the blood and infiltration of the liver by mononuclear cells and neutrophils. Treating the mice with rat IFN-gamma 24 h prior to and 1 h after ConA-challenge markedly exacerbated these signs of hepatitis in a dose-dependent fashion. Moreover, mice injected with lower, non hepatitogenic, doses of ConA (10, 5 mg/kg) became fully susceptible to develop hepatitis upon similar treatment with IFN-gamma. Concordantly, ConA-induced hepatitis was abrogated by either IFN-gamma R-Ig fusion protein or anti-IFN-gamma mAb. These data provide further evidence for the central pathogenetic role of endogenous IFN-gamma in ConA-induced hepatitis and demonstrate the feasibility to prevent disease development by means of a non immunogenic IFN-gamma R-Ig fusion protein.

Dichotomic effects of IFN-gamma on the development of systemic lupus erythematosus-like syndrome in MRL-lpr / lpr mice

Systemic lupus erythematosus (SLE)-prone female MRL-lpr / lpr (MRL-lpr) mice were treated with mouse or rat IFN-gamma under different experimental conditions, both prophylactically in 6- to 8 week-old animals and therapeutically in 12- to 18-week-old SLE-affected mice. It was found that IFN-gamma heterogeneously modulated the course of the disease in MRL-lpr mice. When administered prophylactically, IFN-gamma favorably modulated the histological, serological and clinical signs of the disease. Relative to untreated or PBS-treated control animals, the MRL-lpr mice which received IFN gamma were virtually free of inflammatory infiltration of the kidneys and the lungs, had lower levels of azotemia with reduction of both circulating IgG1, IgG2a and IgG3 and anti-double strand (ds) and single strand (ss) DNA antibodies, milder skin vasculitis, significantly reduced enlargement of their lymph nodes and lower weight of the spleens. IFN-gamma also lowered the rate of mortality of MRL-lpr mice. In contrast to these findings, therapeutically administered IFN-gamma worsened the course of the disease in MRL-lpr mice, which exhibited increased proteinuria, higher levels of IgG2a and IgG3 and anti-ds and -ss DNA antibodies, more aggressive nephritis and died at an earlier age than PBS-treated control mice. The dichotomic effect of IFN-gamma on disease manifestation in MRL-lpr mice offers new insights into the complex role of this cytokine in the regulation of systemic autoimmunity such as SLE.

Concanavalin A-induced hepatitis in mice is prevented by interleukin (IL)-10 and exacerbated by endogenous IL-10 deficiency

One single intra-venous (i.v.) injection of Concanavalin A (Con A) into mice provokes a cell-mediated immunoinflammatory hepatitis. We have presently evaluated the immunopharmacological effects of exogenous interleukin (IL)-10 and the role of endogenous IL-10 in this model by using exogenous IL-10, anti-IL-10 monoclonal antibody (mAb) and mice with disrupted IL-10 gene (IL-10 KO mice). Whilst exogenous IL-10 administered in a prophylactic (1 h prior to Con A) and even "early" therapeutic fashion (30 min after Con A) reduced the elevation of transaminase activities in plasma in a dose-dependent manner, observed in control mice, these biochemical markers of liver injury were significantly increased both in IL-10 KO mice as well as in those receiving anti-IL-10 mAb. Interestingly, doses of Con A lower than 20 mg/kg that were only capable of inducing slight serological signs of hepatitis in mice, exerted marked hepatitic effects when administered to either anti-IL-10 mAb-treated mice or to IL-10 KO mice. The disease modulating effects of exogenous IL-10 and either genetical or pharmacologically-induced IL-10 deficiency were associated with profound and opposite modifications of the Con A-induced increase in the circulating levels of IFN-gamma and TNF-alpha. Relative to control animals, the blood levels of these cytokines were diminished in IL-10-treated mice and augmented in both IL-10 KO mice and anti-IL-10 mAb-treated mice. These results prove the physiological antiinflammatory role of endogenous IL-10 in Con A induced hepatitis and the beneficial effects of IL-10 treatment to prevent this condition.

Anti beta2-glycoprotein I antibodies: clinical significance

The introduction of anticardiolipin antibody (aCL) assay, described in 1983, was able to focus much attention on the study of patients suffering from thrombosis, repeated fetal loss and thrombocytopenia, and allowing the identification of the so called antiphospholipid syndrome (APS). The identification of beta2 glycoprotein I (beta2GPI) as an essential component of the antigenic complex recognized by aCL suggested that this molecule could be a direct target of the antibody response. Since then, different groups have described ELISAs for the detection of anti beta2GPI antibodies, applied to the clinical evaluation of patients with APS, and showing an overall better specificity. Recently, anti beta2GPI were also shown to bind apoptotic bodies resulting in an alteration of their physiological clearance with the triggering of TNFalpha release. This observation suggests that anti beta2GPI may also modify the immunogenicity of apoptotic bodies and of the autoantigens that they contain.

Sodium fusidate in Gillain-Barré syndrome: a case report

A patient with Guillain-Barré syndrome is reported on who responded favourably to a short course treatment with the novel immunosuppressant sodium fusidate (Fucidin), given at a daily dose of 1.5 g for one week. Along with prompt and clear cut clinical improvement, treatment with Fucidin was associated with a rapid decline in the blood concentrations of inflammatory cytokines presumably implicated in the pathogenesis of Guillain-Barré syndrome such as interleukin-2, interferon-gamma, and tumor necrosis factor-alpha. The ex vivo production of these cytokines was also markedly diminished compared with pretreatment values. Fucidin was well tolerated and no clinical or biochemical side effects were seen.

Differential effects of anti-beta2-glycoprotein I antibodies on endothelial cells and on the manifestations of experimental antiphospholipid syndrome

BACKGROUND

The antiphospholipid syndrome (APS) entails a prothrombotic state associated with the presence of anticardiolipin antibodies (aCL). aCL were shown to promote endothelial cell and platelet activation and to induce an APS-like syndrome in mice when administered intravenously. Recent data suggest that aCL target the plasma cofactor beta2-glycoprotein I (beta2GPI) rather than negatively charged phospholipids. However, it has not been determined whether different epitope-specific anti-beta2GPI antibodies obtained from one patient possess pathogenic properties.

METHODS AND RESULTS

Three beta2GPI-binding IgM monoclonal antibodies (mAbs) (ILA-1, ILA-3, and ILA-4) were cloned from a patient with APS. The three antibodies were shown to bind beta2GPI immobilized on irradiated plates, yet only ILA-1 bound beta2GPI coated onto nonirradiated plates. Furthermore, when using the anti-beta2GPI enzyme-linked immunosorbent assay, ILA-1 was the only mAb inhibited by fluid phase beta2GPI. ILA-1 and ILA-3, but not ILA-4, induced adherence of U937 cells to endothelial cells in vitro (reflecting activation of endothelial cells). mAbs ILA-1 and ILA-3 as opposed to ILA-4 induced significant expression of adhesion molecules when preincubated with human umbilical vein endothelial cells. Passive administration of ILA-1 and ILA-3 to pregnant BALB/c mice induced clinical findings consistent with APS (increased fetal resorptions, reduced platelet counts, and prolonged activated partial thromboplastin time), whereas both ILA-4 and the control human IgM did not produce similar effects.

CONCLUSIONS

The results of the study demonstrate the differential effects of various populations of anti-beta2GPI antibodies on endothelial cell activation and on experimental APS.

Deoxyspergualin neither counteracts lipopolysaccharide (LPS) or Staphylococcus aureus enterotoxin-B (SEB) induced lethality in mice nor does it modulate the release of tumor necrosis factor-alpha

To gain further insights into the immunopharmacological mode of action of the immunosuppressant antibiotic deoxyspergualin (DSP), its effects were evaluated in murine lethal endo- and exotoxemia. These are two cytokine-mediated macrophage and T cell dependent immunoinflammatory conditions that can be induced in D-Galactosamine (D-Gal) presensitized mice by the injections with either LPS or SEB, respectively. The results show that prophylactic treatment with DSP (2.5 or 5 mg/kg bd.wt. 48, 24 and 2 h prior to challenge) neither improved the rate of survival, nor influenced the massive increase in the blood levels of tumor necrosis factor-alpha which followed the challenge with LPS or SEB. In sharp contrast, these clinical and seroimmunological events were both markedly counteracted by prophylactic treatment with sodium fusidate, another immunosuppressive agent used as control.

Prevention of spontaneous autoimmune diabetes in diabetes-prone BB rats by prophylactic treatment with antirat interferon-gamma antibody

The role of endogenous interferon-gamma (IFN gamma) in the development of insulin-dependent diabetes mellitus (IDDM) in diabetes-prone BB rats was evaluated. Several groups of these animals were treated under different, experimental conditions with a purified polyclonal antibody (Ab), antirat IFN gamma. The results show that when administered at doses of 100 or 200 micrograms/week from the 30/33th until the 105th day of age, the anti-IFN gamma Ab reversibly reduced the incidence of IDDM compared to that in control rats treated with either irrelevant rabbit IgG or PBS. Moreover, when given up to the 105th day of age, these doses of anti-IFN gamma Abs exerted comparable preventive effects regardless of whether application started as early as within 24 h after birth or at the end of the prediabetic period (e.g. 70/75 days). In contrast, under none of the above experimental conditions did larger doses of anti-IFN gamma Ab (500 micrograms or 1 mg/week) exert antidiabetogenic effects in the BB rats. Apparently, this was due to the exuberant production of neutralizing Abs elicited by the large amount of the xenogeneic Ab injected. At histoimmunological analyses, the BB rats treated with 200 micrograms/ week anti-IFN gamma Abs from 30-80 days of age exhibited a milder insulitic process along with diminished spleen frequency of activated lymphoid cells (MHC class II and interleukin-2 receptor positive). Taken together, these results provide further in vivo evidence for the central pathogenic role of IFN gamma in BB rat IDDM and anticipate the usefulness of specific IFN gamma inhibitors in the prevention of the disease in the clinical setting. Defining novel and less immunogenic forms of specific IFN gamma inhibitors than xenogeneic Abs is important for improving the efficiency of anti-IFN gamma-oriented approaches.

The anti-beta2-glycoprotein I activity in human anti-phospholipid syndrome sera is due to monoreactive low-affinity autoantibodies directed to epitopes located on native beta2-glycoprotein I and preserved during species' evolution

To characterize the reactivity pattern of Abs directed to beta2-glycoprotein I (anti-beta2GPI) in patients with anti-phospholipid syndrome, we have purified anti-beta2GPI Abs by affinity chromatography using the IgG fractions from sera of five different anti-phospholipid syndrome patients. Affinity-purified anti-beta2GPI were shown to be representative of Abs found in human sera because their activity could be virtually abolished from the IgG preparations after repeated absorptions on immobilized human beta2GPI column. Our results show that affinity-purified anti-beta2GPI: 1) do react with beta2GPI in the absence of any phospholipid, as demonstrated by the lack of phosphorus contaminant in the employed reagents, as well as by their comparable binding activity before and after extensive delipidation procedure; 2) can recognize beta2GPI regardless of its origin from different animal species; 3) are able to bind soluble beta2GPI with a mean Kd value of 4.65 x 10(-6) M (range 3, 4-7, 2 x 10(-6) M); 4) significantly enhance their binding avidity when beta2GPI is linked to a solid support; and 5) appear to be mainly monoreactive autoantibodies. In conclusion, we have shown that human polyclonal anti-beta2GPI are low affinity, mainly monoreactive autoantibodies directed to an epitope located on native beta2GPI, preserved along the species evolution.

The anti-beta2-glycoprotein I activity in human anti-phospholipid syndrome sera is due to monoreactive low-affinity autoantibodies directed to epitopes located on native beta2-glycoprotein I and preserved during species' evolution

To characterize the reactivity pattern of Abs directed to beta2-glycoprotein I (anti-beta2GPI) in patients with anti-phospholipid syndrome, we have purified anti-beta2GPI Abs by affinity chromatography using the IgG fractions from sera of five different anti-phospholipid syndrome patients. Affinity-purified anti-beta2GPI were shown to be representative of Abs found in human sera because their activity could be virtually abolished from the IgG preparations after repeated absorptions on immobilized human beta2GPI column. Our results show that affinity-purified anti-beta2GPI: 1) do react with beta2GPI in the absence of any phospholipid, as demonstrated by the lack of phosphorus contaminant in the employed reagents, as well as by their comparable binding activity before and after extensive delipidation procedure; 2) can recognize beta2GPI regardless of its origin from different animal species; 3) are able to bind soluble beta2GPI with a mean Kd value of 4.65 x 10(-6) M (range 3, 4-7, 2 x 10(-6) M); 4) significantly enhance their binding avidity when beta2GPI is linked to a solid support; and 5) appear to be mainly monoreactive autoantibodies. In conclusion, we have shown that human polyclonal anti-beta2GPI are low affinity, mainly monoreactive autoantibodies directed to an epitope located on native beta2GPI, preserved along the species evolution.

The effects of a nonimmunogenic form of murine soluble interferon-gamma receptor on the development of autoimmune diabetes in the NOD mouse

Previous studies have shown that in vivo treatment with antiinterferon-gamma (anti-IFNgamma) monoclonal antibodies (mAbs) prevents the development of autoimmune diabetes in NOD mice. Although these findings anticipate that specific anti-IFNgamma therapies may be useful for the prevention/treatment of human insulin-dependent diabetes mellitus, there are several reasons why the use of anti-IFNgamma mAb may be difficult in the clinical setting. With the aim to develop alternative forms of specific anti-IFNgamma therapies, we recently produced a nonimmunogenic form of the soluble IFNgamma receptor (sIFNgammaR) that binds and neutralizes murine IFNgamma with an affinity higher than that of anti-IFNgamma mAb. In this study we compared the efficacy of sIFNgammaR to that of two anti-IFNgamma mAbs (XMG 1.2 and AN-18) in the prevention of spontaneous and accelerated (cyclophosphamide-induced) forms of autoimmune diabetes in NOD mice. The results show that in the spontaneous model, sIFNgammaR could prevent histological and clinical signs of autoimmune diabetes as efficiently as the two mAbs. Under ex vivo conditions, sIFNgammaR exhibited a more powerful modulatory effect than XMG 1.2 mAb on cytokine secretion from splenic lymphoid cells, which resulted in a significant reduction of Concanavalin A-induced IL-2 secretion and an augmented release of both unstimulated and lipopolysaccharide-induced IL-6. Moreover, although both mAbs were immunogenic and elicited formation of high titers of anti-rat IgG, sIFNgammaR did not induce antibody formation. Unexpectedly, in the cyclophosphamide-induced model, sIFNgammaR turned out to be less effective than either of the two anti-IFNgamma mAbs. Taken together, these data support the role of IFNgamma in the pathogenesis of NOD mice, but, more importantly, suggest that a nonimmunogenic approach is possible to the diminution of the effects of IFNgamma in this model.

Immunomodulatory effects of occupational exposure to mancozeb

The effects of occupational exposure to ethylene-bis-dithiocarbamate of manganese and zinc on the immune system were evaluated in a group of mancozeb-exposed manufacturers and controls. The immune system tests revealed the following: (a) lymphocyte proliferative responses triggered by different activators and mitogen-induced IL-2 production were higher in exposed subjects than in controls; (b) production of monocyte/macrophage-derived IL-1 and polyclonal IgG and IgM, by beta-lymphocytes, did not differ between exposed subjects and controls; (c) percentages and absolute numbers of total T-cells, T-helper cells, T-suppressor/cytotoxic cells, activated T-cells, total beta-cells, and natural killer cells were similar in exposed subjects and controls; (d) serum immunoglobulin classes and complement fractions were within the range of normality; and (e) rheumatoid factor and non-organ-specific serum autoantibodies were absent in exposed and control subjects. An increase in T-cell functional response was found in the exposed group, suggesting a slight immunomodulator effect of mancozeb in conditions of low-level, prolonged occupational exposure.

Circulating serum levels of IL-1ra in patients with relapsing remitting multiple sclerosis are normal during remission phases but significantly increased either during exacerbations or in response to IFN-beta treatment

Interleukin (IL)-1 receptor antagonist (IL-1ra) is a naturally occurring inhibitor of IL-1 which binds to IL-1 receptors without generating immunologic responses. Evidence has recently been provided that the balance between the production of IL-1 and IL-1ra might influence the course of immunoinflammatory diseases such as inflammatory bowel diseases, rheumatoid arthritis (RA) and Lyme arthritis. To assess whether endogenous IL-1ra may also have a role on the course of multiple sclerosis (MS) we presently studied the fluctuation of the serum levels of IL-1ra in patients with relapsing remitting (RR) MS either during remission or exacerbation. Moreover, to evaluate whether the beneficial effect of IFN-beta on the course of MS might also be mediated by an increased production of IL-1ra, we measured the levels of circulating IL-1ra in MS patients prior to and after 6 months of continuous treatment with natural human IFN-beta (6,000,000 IU three times a week for 6 months). Our results demonstrated that, relative to control subjects, IL-1ra serum levels are "normal' during remitting phases of RR MS but significantly elevated either during exacerbations or in response to IFN-beta treatment.

Anti-beta 2-glycoprotein I antibodies: a marker of antiphospholipid syndrome?

Anticardiolipin (aCL) and anti-beta 2-glycoprotein I(anti beta 2GPI) antibodies have been shown in animal models as not cross-reacting antibody populations. This observation prompted us to prove if anti-beta 2GPI exist in human sera by using a reliable method and then to investigate if these are independent from aCl antibodies. We have developed a new ELISA for the detection of anti-beta 2GPI antibodies employing the coating of the protein in carbonate buffer to irradiated microtitre plates and the filtration of serum samples, that makes irrelevant the binding to the uncoated wells. IgG F(ab)2 fragments from IgG positive sera were shown bind beta 2GPI, providing that the binding was a specific antibody binding, mediated by the antigen binding site of the antibody molecule: moreover the antibodies were not able to differentiate native and delipidated beta 2GPI coated plates, making a possible role of a phospholipid contaminant unlikely. On the other hand, the phosphorus content of native as well as delipitated beta 2GPI was undetectable. IgG, but not IgM, anti-beta 2GPI antibodies were classically inhibited by the addition of soluble beta 2GPI, while cardiolipin liposomes appear to modify the reaction in a completely different way, possibly by the described interaction between cardiolipin and beta 2GPI.(ABSTRACT TRUNCATED AT 250 WORDS)

Protection from experimental autoimmune diabetes in the non-obese diabetic mouse with soluble interleukin-1 receptor

We have evaluated the effects of a treatment with soluble interleukin-1 receptor (sIL-1R) in the accelerated model of autoimmune diabetes induced by cyclophosphamide (CY) in the non-obese diabetic (NOD) mouse. Prior to the CY challenge (350 mgkg body weight), female euglycemic NOD mice were randomly divided into three groups (A-C). Groups B and C were treated daily from 1 day before to 13 days after the CY challenge with sIL-1R at doses of 0.2 and 2 mg/kg body weight. Group A was treated with PBS. By 2 weeks after CY administration, an acute form of autoimmune diabetes with glycosuria, hyperglycemia and severe insulitis occurred in the majority (13/20, 65%) of the control mice (group A). In contrast, repeated injections with sIL-1R protected NOD mice from insulin-dependent diabetes mellitus (IDDM) development in a dose-dependent fashion; the incidence of IDDM was 53.3% (8/15) in the mice treated with 0.2 mg/kg and only 6.7% (1/15) in those treated with 2 mg/kg. However, none of the doses of the sIL-1R reduced the extent of insulitis in NOD mice. Importantly, the anti-diabetogenic property of sIL-1R may not involve major T cell function impairment; accordingly, in parallel experiments, splenic lymphoid cells from NOD mice not challenged with CY, but treated with 2 mg/kg sIL-1R for 5 consecutive days showed a normal distribution of mononuclear cell subsets and maintained their capacity to secrete interferon-gamma and IL-2 and to proliferate in response to polyclonal mitogenic stimulation with concanavalin A.

Antiphospholipid antibodies and risk of intrauterine late fetal death

STUDY OBJECTIVE

Goal of the study was to analyze the relationship between anticardiolipin antibodies, lupus anticoagulant and the risk of intrauterine late fetal death.

DESIGN

A case-control study was conducted in a network of general and teaching hospitals in northern Italy. Cases studied were 99 women (median age 27 years), without clinical evidence of systemic lupus erythematosus or other immunological disorders who had an 'unexplained' intrauterine fetal death at or after the 20 weeks of gestation. The control subjects were 85 women (median age 28 years) who gave birth at term (> 37 weeks gestation) to healthy infants on randomly selected days at the same hospitals where cases had been identified.

RESULTS

The presence of lupus anticoagulant was detected in four of the 99 cases (4%, 95% confidence interval 2%-15%) and none of the 85 controls. A total of 10 out of the 89 cases (11%, 95 confidence interval 6%-23%), but none of the 79 controls for whom anticardiolipin antibodies value was available had elevated anticardiolipin antibodies; this difference was statistically significant (chi 2(1) = 9.38, p < 0.01).

Toxicological and immune findings in workers exposed to pentachlorophenol (PCP)

Pentachlorophenol (PCP) is a pesticide used worldwide in industrial and domestic applications. Data available on the effects of technical-grade PCP on the immune system are insufficient and equivocal; some data indicate inhibitory effects, whereas others suggest stimulating effects. This study was performed to evaluate toxicological and immune findings in 32 subjects who had prolonged exposure to PCP in a wood factory and in 37 controls. PCP concentrations were determined in plasma and urine of all subjects. Lymphocyte subsets of CD3-, CD4-, and CD8-positive cells were evaluated, and the proliferative response of peripheral blood mononuclear cells (PBM) to mitogens was assessed. The results suggested the absence of major laboratory and clinical signs of PCP-dependent immune deficiency. A weak effect of long-term exposure to PCP on the functional immune response could not be ruled out because of the finding of a decreased response to 5% PHA in the high-exposure group. A weak effect against hepatocyte membrane was evidenced by the finding of raised serum concentration of glycocholic, taurodeoxycholic, and glycochenodeoxycholic acids in subjects directly exposed to PCP for more than 10 y.

In vivo treatment with a monoclonal antibody to interferon-gamma neither affects the survival nor the incidence of lupus-nephritis in the MRL/lpr-lpr mouse

The effects of the in vitro treatment with a mAb (DB-1) that neutralizes mouse IFN-gamma on the development of the SLE-like syndrome in MRL/lpr-lpr (MRL-lpr) mice were studied. The results show that the i.p. administration of 2.6 mg/week of DB-1 from the 12th to the 20th week of age neither affected the survival nor the incidence and severity of lupus nephritis in MRL-lpr mice. This study argues against the pathogenic relevance of IFN-gamma in this experimental model of human SLE.

A new case of IgE myeloma

A new case of IgE myeloma is described. A 77-year-old woman presented with bone pain and fatigue. Serum protein analysis revealed a paraprotein of the IgE kappa type; bone marrow aspirate and immunofluorescence confirmed the diagnosis; ultrastructural examination showed immature plasma cells. Treatment with prednisone, melphalan, cyclophosphamide and interferon alfa did not produce any improvement and the patient died 5 months after diagnosis. The patient's clinical and laboratory data are compared with those of IgE myeloma cases reported in the literature.

Gastric histology and function tests in Italian patients with dermatitis herpetiformis

Gastric mucosal histology and function were evaluated in 57 Italian subjects with dermatitis herpetiformis (DH), by means of multiple endoscopic biopsies, gastrin and pepsinogen I (Pg I) serum levels, and parietal cell antibodies (PCA). One hundred and forty-nine patients with nonulcer dyspepsia served as reference population for the prevalence of atrophic gastritis of the body. Seventeen DH patients (30%) and 23 controls (15.4%) showed atrophic gastritis of the body mucosa (p less than 0.05). Nine of the DH patients with atrophic gastritis of the body also had atrophic changes in the antrum. Six patients, all with severe atrophic gastritis, had high gastrin levels and PCA; five of these six also had low Pg I levels. We found an increased prevalence of abnormal indirect function tests among patients with atrophic gastritis is due to the younger age of the patients in our series. Thus, atrophic gastritis can be detected early on a histologic basis, but functional impairment occurs later, as the mucosal damage increases in severity.

Neutrophil Function during Cyclic Chemotherapy for Cancer Disease

A study of some aspects of granulocyte function was carried out before, during, and after cyclic chemotherapy in 9 patients surgically treated for carcinoma and in 6 patients with very advanced and inoperable cancer. In most patients, total leukocyte mobilization, Candida-stimulated nitroblue tetrazolium dye reduction, and phagocytosis increased after chemotherapy. Furthermore, delayed hypersensitivity skin reactions to PPD and above all to Varidase increased in the same cases. A significant correlation between accumulation of polymorphonuclear leukocytes into skin chambers and skin tests was found in both groups of patients (p < 0.001). In some instances, fluctuations in the levels of circulating immune complexes without a distinct correlation between these complexes and granulocyte function were found. The data support the hypothesis that depressed granulocyte function may contribute to an increased susceptibility to infections and may be considered an additional factor that favors tumor dissemination. Chemotherapy seems to restore polymorphonuclear function and delayed hypersensitivity skin reactions.