T helper cell dysfunction in systemic lupus erythematosus (SLE): relation to disease activity

Risk of Bloodstream Infection in Patients with Systemic Lupus Erythematosus Exposed to Prolonged Medium-to-High-Dose Glucocorticoids

OBJECTIVES

This study aimed to investigate the incidence rate and risk factors of bloodstream infection (BSI) in patients with systemic lupus erythematosus (SLE) exposed to medium to high doses of glucocorticoids.

METHODS

This study included 1109 treatment episodes with prolonged (≥4 weeks) medium-to-high-dose glucocorticoids (≥15 mg/day prednisolone) in 612 patients with SLE for over 14 years. Clinical features regarding systemic lupus erythematosus disease activity index 2000 (SLEDAI-2K), immunosuppressant use, and laboratory results were obtained from the electronic medical database. The primary outcome of this study was the 1-year incidence of BSI. The effect of clinical factors on the outcome was investigated using a generalized estimating equation.

RESULTS

During a total of 1078.64 person-years, 30 cases of BSI occurred, with an incidence rate of 2.78 (95% confidence interval (CI) 1.88-3.97) per 100 person-years. Mortality rate of the treatment episodes with BSI was 16.7%, which was significantly higher than that in the other episodes (incidence rate ratio (IRR) 19.59, 95% CI 7.33-52.44). When the incidence rate of BSI was stratified by baseline glucocorticoid dose and SLEDAI-2K score, a higher incidence rate of BSI occurred as disease activity or baseline glucocorticoid dose increased. In the multivariable analysis, SLEDAI-2K ≥20 (adjusted IRR (aIRR) 4.66, 95% CI 2.17-10.00), initial baseline prednisolone ≥ 60 mg/day (aIRR 2.42, 95% CI 1.11-5.32), and cumulative prednisolone dose ≥15 mg/day during the previous 6 months (aIRR 2.13, 95% CI 1.03-4.40) significantly increased the risk of BSI.

CONCLUSION

In patients with SLE exposed to prolonged medium-to-high-dose glucocorticoids, the 1-year incidence rate of BSI was significantly higher than previously reported in the general patients with SLE. Severe disease activity, and high-dose glucocorticoid treatment previously or at baseline increased the risk of BSI.

Immunogenicity of Hepatitis B Vaccine in Pediatric Systemic Lupus Erythematosus Patients

BACKGROUND

Pediatric patients with systemic lupus erythematosus (SLE) are at increased infectious risk caused by underlying immunologic dysregulation and immunosuppressive therapy. Hepatitis B virus (HBV) could be reactivated during the immunosuppressive treatment in patients with past HBV infections. Information on immunogenicity after hepatitis B (HB) immunization and reimmunization are still scarce.

METHODS

SLE patients 5-18 years of age who had completed a primary HB immunization were enrolled. Anti-HBs levels at enrollment and after each vaccine dose were determined. Patients with anti-HBs levels < 10 mIU/mL were administered 1 booster dose. After 1 booster dose, patients with negative anti-HBs levels were administered 2 more booster doses.

RESULTS

Ninety-three SLE patients were enrolled. The prevalence of seroprotection assessed by anti-HBs > 10 mIU/mL after completion of a primary HB immunization was 25.8% (95% CI: 17.2-34.4). Lupus nephritis was associated with unprotective anti-HBs levels [odds ratio (OR): 4.341; 95% CI: 1.044-18.040]. The anti-HBs seroconversion was 72.3% (95% CI: 61.5-83.0) after 1 booster dose and increased up to 93.4% (95% CI: 86.9-98.4) after 3 booster doses. SLE Disease Activity Index-2000 score ≥ 4 (OR: 4.625; 95% CI: 1.45-14.80) was significantly associated with nonseroconversion after the first booster dose. Hypocomplementemia before the first and second booster doses (OR: 27; 95% CI: 1.26-578.35) was significantly associated with nonseroconversion after 3 booster doses.

CONCLUSIONS

All pediatric SLE patients should be evaluated for HBV serological status before immunosuppressive treatment. SLE patients with SLE Disease Activity Index-2000 score > 4 should need 3 booster doses if their anti-HBs level was < 10 mIU/mL.

Clinical characteristics of SLE patients infected with Epstein-Barr virus and potential associated risk factors

OBJECTIVE

To investigate the clinical features and potential associated risk factors of Epstein-Barr virus (EBV) DNA positivity in systemic lupus erythematosus (SLE) patients.

METHODS

A total of 121 newly diagnosed SLE patients who had never used immunosuppressive drugs (treatment-naïve) and 191 previously treated SLE patients from January 2017 to January 2020 were enrolled in this study. And 115 age- and sex-matched non-rheumatic disease controls were also included.

RESULTS

A significantly higher incidence of EBV DNA positivity and higher viral DNA copies in peripheral blood mononuclear cells were observed among treatment-naïve and previously treated SLE patients compared with controls. The positivity rate of EBV DNA was further increased in previously treated SLE patients compared with that in treatment-naïve patients. EBV DNA-positive treatment-naïve SLE patients presented lower incidence of hemolytic anemia and more affected organ number than EBV DNA-negative patients. EBV DNA-positive treated SLE patients showed older age, longer immunosuppressive duration, higher IgG level, and higher Th/Ts ratio than EBV DNA-negative patients. Patients responding well to treatment with decreased SLE disease activity index scores had a transformation of EBV DNA from positive to negative in treated SLE patients. Multivariate logistic regression analysis showed that older age, higher IgG level, and longer immunosuppressive duration were associated risk factors for EBV DNA positivity in SLE patients, while higher TNF-α level was a protective factor.

CONCLUSION

Older age, higher IgG level, and longer immunosuppressive duration are associated with the positivity of EBV DNA in SLE patients. A seroconversion of EBV DNA indicates an association between EBV positivity and therapy response, while larger number cases are needed to confirm. Key Points • Older age, higher IgG level, and longer immunosuppressive duration are associated with EBV DNA positivity in SLE patients. • A seroconversion of EBV DNA might be an indicator to reflect the SLE therapy -response.

Immunogenicity and Safety of mRNA Anti-SARS-CoV-2 Vaccines in Patients with Systemic Lupus Erythematosus

Vaccination is the most effective preventive measure to control the spread of COVID-19 and reduce associated complications. This study aims to evaluate the efficacy and safety of mRNA COVID-19 vaccines in patients with systemic lupus erythematosus (SLE). A total of 41 adult SLE patients receiving two doses of the SARS-CoV-2 mRNA Comirnaty-BioNTech/Pfizer vaccine were enrolled. The quantitative determination of anti-trimeric spike protein-specific IgG antibodies to SARS-CoV-2 was assessed before (T0), 21 days after the administration of the first dose of the vaccine (T1), and between 21 and 28 days after the second dose (T2). They were compared with the same determinations from a cohort of 29 patients with C1-esterase inhibitor deficiency hereditary angioedema (C1-INH-HAE) as controls. All the SLE patients and controls demonstrated a positive serological response after a single dose of the vaccine (T1), which significantly increased after the second dose (T2). No significant difference was found between SLE patients and controls at T1 [t(52.81) = -0.68; p = 0.49] and at T2 [t(67.74) = -0.22; p = 0.825]. Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) analysis showed that the vaccine did not influence SLE activity or caused disease flare in our cohort. In conclusion, COVID-19 vaccines produced a satisfactory response in SLE patients without variation in the disease activity.

Reactivation of Chagas Disease in a Patient With an Autoimmune Rheumatic Disease: Case Report and Review of the Literature

Reactivation of Chagas disease has been described in immunosuppressed patients, but there is a paucity of literature describing reactivation in patients on immunosuppressive therapies for the treatment of autoimmune rheumatic diseases. We describe a case of Chagas disease reactivation in a woman taking azathioprine and prednisone for limited cutaneous systemic sclerosis (lcSSc). Reactivation manifested as indurated and erythematous cutaneous nodules. Sequencing of a skin biopsy specimen confirmed the diagnosis of Chagas disease. She was treated with benznidazole with clinical improvement in the cutaneous lesions. However, her clinical course was complicated and included disseminated CMV disease and subsequent septic shock due to bacteremia. Our case and review of the literature highlight that screening for Chagas disease should be strongly considered for patients who will undergo immunosuppression for treatment of autoimmune disease if epidemiologically indicated.

Atypische Infektionen unter Immunsuppression

Rasches Handeln ist gefragt, wenn der Verdacht auf eine Infektion bei einem immunsupprimierten Patienten besteht. Wenn es sich nicht gerade um einen tropischen Keim von der Kreuzfahrt bzw. den multiresistenten Keim von einem der letzten Klinikaufenthalte handelt – der Erreger ist meist nicht das Problem! Es ist seine Präsentation, die Ausprägung seiner klinischen Manifestation und seine Reaktion auf die Therapie, die für uns zur Herausforderung wird. Ist stets die Veränderung der Immunreaktion durch immer selektiver wirksame Biologika das Thema? Oder müssen wir uns erst mit den Reaktionen des innaten und adaptiven Immunsystems vertraut machen, um zu verstehen, was wir sehen?

Systemic lupus erythematosus and risk of infection

INTRODUCTION

Systemic lupus erythematosus (SLE) is an autoimmune disorder that affects almost every organ system and it is treated with immunomodulation and immunosuppression. SLE patients have an intrinsically dysfunctional immune system which is exacerbated by disease activity and leaves them vulnerable to infection. Treatment with immunosuppression increases susceptibility to infection, while hydroxychloroquine use decreases this risk. Infectious diseases are a leading cause of hospitalization and death.

AREAS COVERED

This narrative review provides an overview of recent epidemiology and predictors of infections in SLE, delineates the risk of infection by therapeutic agent, and provides suggestions for risk mitigation. Articles were selected from Pubmed searches conducted between September 2019 and January 2020.

EXPERT OPINION

Despite the large burden of infection, effective and safe preventative care such as universal hydroxychloroquine use and vaccination are underutilized. Future efforts should be directed to quality improvement, glucocorticoid reduction, and validation of risk indices that identify patients at the highest risk of infection.

Comparing the burdens of opportunistic infections among patients with systemic rheumatic diseases: a nationally representative cohort study

Objective

To estimate and compare the burdens of opportunistic infections and herpes zoster in real-world practice among patients with various systemic rheumatic diseases.

Methods

This 13-year cohort study used national health insurance data to compare the incidence rates (IRs) of nine opportunistic infections among patients with five rheumatic diseases. The analyses were stratified according to follow-up duration using Poisson regression, and Cox models were used to compare the risk of first opportunistic infection.

Results

During 2000–2013, we identified 76,966 patients who had polymyositis/dermatomyositis (PM/DM, 2270 cases), systemic lupus erythematosus (SLE, 15,961 cases), systemic sclerosis (SSc, 2071 cases), rheumatoid arthritis (RA, 38,355 cases), or primary Sjögren’s syndrome (pSS, 18,309 cases). The IR of opportunistic infections was highest for PM/DM cases (61.3/1000 person-years, 95% confidence interval [CI] 56.6–66.2), followed by SLE cases (43.1/1000 person-years, 95% CI 41.7–44.5), SSc cases (31.6/1000 person-years, 95% CI 28.3–35.1), RA cases (25.0/1000 person-years, 95% CI 24.4–25.7), and pSS cases (24.1/1000 person-years, 95% CI 23.1–25.2). Multivariable Cox analysis revealed that, relative to SLE, PM/DM was associated with a significantly higher risk of opportunistic infections (hazard ratio 1.18, 95% CI 1.08–1.29). The risk of opportunistic infections was highest during the first year after the diagnosis of all five rheumatic diseases.

Conclusions

The risk of opportunistic infection was highest for PM/DM, followed by SLE, SSc, RA, and pSS. Careful observation and preventive therapy for opportunistic infections may be warranted in selected PM/DM patients, especially during the first year after the diagnosis.

Increased susceptibility against Cryptococcus neoformans of lupus mouse models (pristane-induction and FcGRIIb deficiency) is associated with activated macrophage, regardless of genetic background

The severity of cryptococcosis in lupus from varying genetic-backgrounds might be different due to the heterogeneity of lupus-pathogenesis. This study explored cryptococcosis in lupus mouse models of pristane-induction (normal genetic-background) and FcGRIIb deficiency (genetic defect). Because the severity of lupus nephritis, as determined by proteinuria and serum creatinine, between pristane and FcGRIIb-/- mice were similar at 6-month-old, Cryptococcus neoformans was intravenously administered in 6-month-old mice and were age-matched with wild-type. Indeed, the cryptococcosis disease severity, as evaluated by mortality rate, internal-organ fungal burdens and serum cytokines, between pristane and FcGRIIb-/- mice was not different. However, the severity of cryptococcosis in wild-type was less severe than the lupus mice. On the other hand, phagocytosis activity of peritoneal macrophages from lupus mice (pristane and FcGRIIb-/-) was more predominant than the wild-type without the difference in macrophage killing-activity among these groups. In addition, the number of active T helper cells (Th-cell) in the spleen, including Th-cells with intracellular IFN-γ, from lupus mice (pristane and FcGRIIb-/-) was higher than wildtype. Moreover, these active Th-cells were even higher after 2 weeks of cryptococcal infection. These data support enhanced macrophage activation through prominent Th-cells in both lupus models. In conclusion, an increased susceptibility of cryptococcosis in both lupus models was independent to genetic background. This might due to Th-cell enhanced macrophage phagocytosis with the interference of macrophage killing activity from Cryptococcal immune-evasion properties.

Impaired TGF-β signaling in patients with active systemic lupus erythematosus is associated with an overexpression of IL-22

The mechanisms leading to the disruption of self-tolerance in systemic lupus erythematosus (SLE) remain elusive. Herein, we aimed to decipher the molecular basis of the impaired response of mononuclear cells to TGF-β1. The Smad3-pathway was explored on CD3+ lymphocytes in either active or non active SLE patients. An impaired transcription of TGF-β1 target genes was demonstrated in the CD3+ lymphocytes of active SLE patients confirming that the defect involves T cells and pointing to its extrinsic nature. We further demonstrate that the defect did not result from an impaired TGF-βRII expression or Smad2/3 phosphorylation suggesting that the mechanism lies downstream Smad2/3 translocation. Interestingly, the TGF-1 signaling defect did not correlate with an increased expression of soluble or membrane-bound IL-15. However, it was associated with an overexpression of IL-22. This suggests that an excessive activation of AhR pathway (through UV radiations, infections, etc.) could lead to the inhibition of immunosuppressive actions of TGF-β thus disrupting immune homeostasis in SLE. Collectively, our data suggest that the impaired response to TGF-β in SLE patients is associated with disease activity and provide new insights into the pathogenesis of SLE since it could establish the link between the environmental factors and the aberrancies of the immune system usually described in SLE.

Cutaneous mucormycosis in a patient with lupus nephritis: A case report and review of literature

RATIONALE

Mucormycosis is a rare fungal infection but life-threatening, especially in lupus nephritis (LN). Mucormycosis may manifest as rhino-orbital-cerebral, pulmonary, cutaneous, gastrointestinal, renal, or disseminated forms.

PATIENT CONCERNS

We report a case of a 52-year-old woman with cutaneous mucormycosis infection who was admitted because of LN.

DIAGNOSES

Histopathological analysis of the lesion confirmed the Rhizopus microspores from the family Mucoraceae.

INTERVENTIONS AND OUTCOMES

The mortality of mucormycosis remains unacceptably high. Our patient died at last even with standard therapy (aggressive surgical debridement and anti-mucormycosis drugs).

LESSONS

It is difficult to diagnose because lacking of specific clinical features, it is necessary to identify the susceptible patients, and then make diagnosis rapidly through tissue biopsy. Despite the outcome is poor, aggressive surgical debridement and Amphotericin B/Posaconazole can be effective.

Overview of Infections in the Immunocompromised Host

Understanding the components of the immune system that contribute to host defense against infection is key to recognizing infections that are more likely to occur in an immunocompromised patient. In this review, we discuss the integrated system of physical barriers and of innate and adaptive immunity that contributes to host defense. Specific defects in the components of this system that predispose to particular infections are presented. This is followed by a review of primary immunodeficiency diseases and secondary immunodeficiencies, the latter of which develop because of a specific illness or condition or are treatment-related. The effects of treatment for neoplasia, autoimmune diseases, solid organ and stem cell transplants on host defenses are reviewed and associated with susceptibility to particular infections. In conclusion, an approach to laboratory screening for a suspected immunodeficiency is presented. Knowledge of which host defects predispose to specific infections allows clinicians to prevent, diagnose, and manage infections in their immunocompromised patients most effectively.

Infection Risk and Safety of Corticosteroid Use

Corticosteroids are frequently used to treat rheumatic diseases. Their use comes with several well-established risks, including osteoporosis, avascular necrosis, glaucoma, and diabetes. The risk of infection is of utmost concern and is well documented, although randomized controlled trials of short-term and lower-dose steroids have generally shown little or no increased risk. Observational studies from the real world, however, have consistently shown dose-dependent increases in risk for serious infections as well as certain opportunistic infections. In patients who begin chronic steroid therapy, vaccination and screening strategies should be used in an attempt to mitigate this risk.

Intrinsic Differences in Donor CD4 T Cell IL-2 Production Influence Severity of Parent-into-F1 Murine Lupus by Skewing the Immune Response Either toward Help for B Cells and a Sustained Autoantibody Response or toward Help for CD8 T Cells and a Downregulatory Th1 Response

Using the parent-into-F1 model of induced lupus and (C57BL/6 × DBA2) F1 mice as hosts, we compared the inherent lupus-inducing properties of the two parental strain CD4 T cells. To control for donor CD4 recognition of alloantigen, we used H-2(d) identical DBA/2 and B10.D2 donor T cells. We demonstrate that these two normal, nonlupus-prone parental strains exhibit two different T cell activation pathways in vivo. B10.D2 CD4 T cells induce a strong Th1/CMI pathway that is characterized by IL-2/IFN-γ expression, help for CD8 CTLs, and skewing of dendritic cell (DC) subsets toward CD8a DCs, coupled with reduced CD4 T follicular helper cells and transient B cell help. In contrast, DBA/2 CD4 T cells exhibit a reciprocal, lupus-inducing pathway that is characterized by poor IL-2/IFN-γ expression, poor help for CD8 CTLs, and skewing of DC subsets toward plasmacytoid DCs, coupled with greater CD4 T follicular helper cells, prolonged B cell activation, autoantibody formation, and lupus-like renal disease. Additionally, two distinct in vivo splenic gene-expression signatures were induced. In vitro analysis of TCR signaling revealed defective DBA CD4 T cell induction of NF-κB, reduced degradation of IκBα, and increased expression of the NF-κB regulator A20. Thus, attenuated NF-κB signaling may lead to diminished IL-2 production by DBA CD4 T cells. These results indicate that intrinsic differences in donor CD4 IL-2 production and subsequent immune skewing could contribute to lupus susceptibility in humans. Therapeutic efforts to skew immune function away from excessive help for B cells and toward help for CTLs may be beneficial.

High Affinity Antibodies against Influenza Characterize the Plasmablast Response in SLE Patients After Vaccination

Breakdown of B cell tolerance is a cardinal feature of systemic lupus erythematosus (SLE). Increased numbers of autoreactive mature naïve B cells have been described in SLE patients and autoantibodies have been shown to arise from autoreactive and non-autoreactive precursors. How these defects, in the regulation of B cell tolerance and selection, influence germinal center (GC) reactions that are directed towards foreign antigens has yet to be investigated. Here, we examined the characteristics of post-GC foreign antigen-specific B cells from SLE patients and healthy controls by analyzing monoclonal antibodies generated from plasmablasts induced specifically by influenza vaccination. We report that many of the SLE patients had anti-influenza antibodies with higher binding affinity and neutralization capacity than those from controls. Although overall frequencies of autoreactivity in the influenza-specific plasmablasts were similar for SLE patients and controls, the variable gene repertoire of influenza-specific plasmablasts from SLE patients was altered, with increased usage of JH6 and long heavy chain CDR3 segments. We found that high affinity anti-influenza antibodies generally characterize the plasmablast responses of SLE patients with low levels of autoreactivity; however, certain exceptions were noted. The high-avidity antibody responses in SLE patients may also be correlated with cytokines that are abnormally expressed in lupus. These findings provide insights into the effects of dysregulated immunity on the quality of antibody responses following influenza vaccination and further our understanding of the underlying abnormalities of lupus.

Risk factors for invasive Cryptococcus neoformans diseases: a case-control study

Background

Cryptococcus neoformans is a ubiquitous environmental fungus that can cause life-threatening meningitis and fungemia, often in the presence of acquired immunodeficiency syndrome (AIDS), liver cirrhosis, diabetes mellitus, or other medical conditions. To distinguish risk factors from comorbidities, we performed a hospital-based, density-sampled, matched case-control study.

Methods

All new-onset cryptococcal meningitis cases and cryptococcemia cases at a university hospital in Taiwan from 2002–2010 were retrospectively identified from the computerized inpatient registry and were included in this study. Controls were selected from those hospitalized patients not experiencing cryptococcal meningitis or cryptococcemia. Controls and cases were matched by admission date, age, and gender. Conditional logistic regression was used to analyze the risk factors.

Results

A total of 101 patients with cryptococcal meningitis (266 controls) and 47 patients with cryptococcemia (188 controls), of whom 32 patients had both cryptococcal meningitis and cryptococcemia, were included in this study. Multivariate regression analysis showed that AIDS (adjusted odds ratio [aOR] = 181.4; p < 0.001), decompensated liver cirrhosis (aOR = 8.5; p = 0.008), and cell-mediated immunity (CMI)-suppressive regimens without calcineurin inhibitors (CAs) (aOR = 15.9; p < 0.001) were independent risk factors for cryptococcal meningitis. Moreover, AIDS (aOR = 216.3, p < 0.001), decompensated liver cirrhosis (aOR = 23.8; p < 0.001), CMI-suppressive regimens without CAs (aOR = 7.3; p = 0.034), and autoimmune diseases (aOR = 9.3; p = 0.038) were independent risk factors for developing cryptococcemia. On the other hand, diabetes mellitus and other medical conditions were not found to be risk factors for cryptococcal meningitis or cryptococcemia.

Conclusions

The findings confirm AIDS, decompensated liver cirrhosis, CMI-suppressive regimens without CAs, and autoimmune diseases are risk factors for invasive C. neoformans diseases.

Infection risk in systemic lupus erythematosus patients: susceptibility factors and preventive strategies

Infection is one of the leading causes of morbidity and mortality in systemic lupus erythematosus (SLE). Bacterial infections are most frequent, followed by viral and fungal infections. The impaired cellular and humoral immune functions seen in patients with SLE are predisposing conditions, whilst disease activity, prednisone doses over 7.5–10 mg/day, high doses of methylprednisolone or cyclophosphamide are well-recognised risk factors for infection. The first six months after rituximab treatment and the use of more than three courses are also associated with an increased susceptibility for infection. It has not been established whether belimumab, azathioprine and mycophenolate mofetil increase the risk of serious infections. Most vaccines are effective and safe in SLE patients, although vaccination should be avoided during periods of active disease. Live virus vaccines are contraindicated for immunosuppressed patients. Influenza and pneumococcal vaccines are universally recommended. Tuberculosis prophylaxis should be considered in selected cases. Therefore, it is advisable not to exceed doses of 5 mg/day of prednisone in chronic treatment. Methylprednisolone and cyclophosphamide should be used in low-dose regimens. Antimalarials have a well-known protective role against infection, in addition to other beneficial properties, thus, hydroxychloroquine is recommended for all SLE patients where no contraindication exists.

Invasive fungal infections in Argentine patients with systemic lupus erythematosus

Introduction

Infections are the leading cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Invasive fungal infections (IFI) comprise a group of diseases caused by Cryptococcus, Histoplasma, Aspergillus and Candida. Few studies of IFI have been published in patients with SLE and associated factors have not been completely defined.

Objectives

The objectives of this paper are to estimate the frequency of IFI in admitted patients with SLE in our hospital, to determine the risk factors associated with IFI in our patients with SLE, and to compare IFI group with a control group (SLE without IFI).

Methods

The medical charts of patients with IFI (EORTC/MSG, 2008) and SLE (ACR, 1997) admitted to our hospital from June 2001 until June 2012 were reviewed. To identify factors associated with IFI, we developed a case-control study (SLE + IFI vs SLE alone) in a one to three ratio adjusted for sex and age and hospitalization for other reasons. Comparison was made of demographic characteristics, duration of disease and disease activity previous to IFI diagnosis, especially three months before fungal infection. We defined severe activity as SLEDAI ≥ 8. Infection by fungi of the genus Candida was considered only in its disseminated form.

Results

Ten cases of IFI were identified in 208 patients with SLE admitted between June 2001 and June 2012. We included 40 patients with SLE (10 with IFI and 30 controls). Of the SLE-IFI patients, eight were women and the average age was 27.5 years (range, 19–42 years). Fungal isolation: eight Cryptococcus neoformans, one Histoplasma capsulatum and one Candida albicans. Sites affected: five in peripheral blood, five in central nervous system (CNS), four in skin/soft tissue and one in pleura. Mortality was 40% ( p = 0.002), with Cryptococcus neoformans being the most common fungus. The SLE disease activity was severe in 70% of infected patients and no significant difference with the control group was found ( p = 0.195). We also found no association with leukopenia, lymphopenia, hypocomplementemia, hypogammaglobulinemia or anti-DNA positivity; neither with meprednisone doses >20 mg/day or intravenous methylprednisolone pulse therapy before fungal infection. The use of immunosuppressive therapy with azathioprine showed a significant association ( p = 0.017). Cyclophosphamide ( p = 0.100) or mycophenolate mofetil ( p = 0.256) did not show similar results.

Conclusion

The frequency of IFI in hospitalized SLE patients in our hospital was 4.8%. Cryptococcus neoformans was the most common etiologic agent and was primarily responsible for the deaths in this cohort. These data are consistent with publications in East Asia rather than North America where Candida spp. is more common. Unlike other publications, previous immunosuppression with azathioprine was the only risk factor associated with the development of the infection. Invasive fungal infection should be suspected in hospitalized patients with SLE and immunosuppression with CNS or atypical cutaneous manifestation of SLE in order to start appropriate treatment early and obtain better outcome.

T-cell specific defect in expression of the NTPDase CD39 as a biomarker for lupus

Regulatory T cells (T(regs)) are critical for maintenance of peripheral tolerance via suppression of T-cell responses, and absence of T(regs) results in autoimmunity. The role of aberrations in the T(reg) pool for the development of systemic lupus erythematosus (SLE, lupus) remains uncertain. T(reg)-mediated generation of adenosine, dependent on the ectonucleotidase CD39, is an important mechanism for suppression of T-cell responses. We tested whether decreases in numbers of T(regs), and specifically CD39-expressing T(regs), are associated with human lupus. We studied 15 SLE patients, six patients with rheumatoid arthritis (RA) and 24 healthy controls. T(reg) phenotypic markers, including CD39 expression, were studied by flow cytometry. Varying numbers of sorted T(regs) cells were co-cultured with responder T (T(resp)) cells, with proliferation assessed by (3)H-thymidine incorporation. The proportion of T(regs) as defined by Foxp3(+) CD25(+high) CD127(-/low) was similar in lupus and control populations. CD39-expressing T(regs) comprised 37±13% of the T(reg) population in healthy controls and 36±21% in lupus subjects using nonsteroidal immunosuppressants to control active disease, but was nearly absent in five of six lupus subjects with minimally active disease. In contrast to healthy controls and lupus subjects without the CD39 defect, in SLE subjects with the CD39 defect, adenosine-dependent T(reg)-mediated suppression was nearly absent. These results suggest that functional defects in T(regs), rather than reduced T(reg) numbers, are important for the loss of peripheral tolerance in lupus. Presentation of this defect may serve as a biomarker for untreated disease.

Resistance to exogenous TGF-β effects in patients with systemic lupus erythematosus

BACKGROUND

The mechanisms underlying the loss of self-tolerance in systemic lupus erythematosus (SLE) are incompletely deciphered. TGF-β plays a key role in self-tolerance demonstrated by the onset of a fatal autoimmune syndrome associated with lupus autoantibodies in mice lacking a functional TGF-β receptor. The present work aims to define whether resistance to TGF-β might contribute to the pathogenesis of SLE.

METHODS

Twenty-two patients with active SLE, 16 with other connective tissue diseases, and 10 healthy controls were prospectively included in this study. The effects of exogenous TGF-β1 on IL-2-dependent T-cell proliferation, IFN-γ secretion, and target gene transcription were analyzed on peripheral blood mononuclear cells.

RESULTS

Our results showed that 75% of patients with SLE or other connective tissue diseases were totally or partially resistant to the effects of TGF-β1. The responses to the anti-proliferative and transcriptional effects of TGF-β were, however, discordant in a high proportion of our patients. Hence, we distinguish three distinct profiles of resistance to TGF-β1 and suggest that patients may exhibit different defects affecting distinct points of TGF-β1 signaling pathways.

CONCLUSION

Our data demonstrate the presence of an impaired response of peripheral cells to TGF-β1 in patients with active SLE that may participate to the pathogenesis of the disease. Further studies will be necessary to delineate the mechanisms underlying the lymphocyte resistance to TGF-β1 in SLE.

Meningitis in Korean patients with systemic lupus erythematosus: analysis of demographics, clinical features and outcomes; experience from affiliated hospitals of the Catholic University of Korea

Meningitis is a rare complication of systemic lupus erythematosus (SLE), potentially leading to a fatal outcome. The demographic, clinical, and laboratory features, and the outcomes of meningitis were evaluated in Korean patients with SLE. In a retrospective medical record review of 1420 SLE patients, 20 patients who had developed septic or aseptic meningitis were identified. In 11 patients, the causative microorganisms were identified ('septic meningitis'), and Cryptococcus neoformans was the major pathogen. The other nine patients were diagnosed with aseptic meningitis. The patients with septic meningitis were older than those with aseptic meningitis (p = 0.025) and displayed mental changes more often (p = 0.005). Leukocyte counts in the cerebrospinal fluid (CSF) were higher (p = 0.044) and the levels of CSF glucose were lower in the septic meningitis group (p = 0.036). Plasma leukocyte counts and neutrophil counts were higher in patients with septic meningitis (p = 0.037 and p = 0.020, respectively). Meningitis was observed in 1.4% of Korean patients with SLE and, in 55% of the meningitis patients, microorganisms were isolated and Cryptococcus neoformans was most commonly identified. Altered mental status, plasma leukocytosis, neutrophilia, and CSF pleocytosis and hypoglycemia were more prominent in patients with septic meningitis.

Advances in lupus stemming from the parent-into-F1 model

The parent-into-F1 model has led to important advances in our understanding of lupus. Here, we review the work in murine lupus that elucidated the role of T cells and supported the conclusion that the parent-into-F1 model of induced lupus compares favorably with de facto gold standard spontaneous models of lupus. Then we focus on recent work in parent-into-F1 mice, which has yielded novel insights into unresolved controversies, such as the role of apoptosis in the pathogenesis of lupus and lupus in patients receiving TNF blockade. Finally, the review considers the evidence that supports a potential role for CD8 T cells, both cytotoxic and memory cells, in mediating disease remission.

Defective in vitro IL-2 production in lupus is an early but secondary event paralleling disease activity: evidence from the murine parent-into-F1 model supports staging of IL-2 defects in human lupus

T cell defects are a well described feature of both human and murine lupus however their exact significance is unclear. Evidence from an induced model of lupus, the P --> F1 model of chronic lupus-like GVHD demonstrates that a secondary inducible T cell defect in in vitro IL-2 and CTL responses occurs early in the course of lupus-like disease and well in advance of clinical disease. Defective Th cell function was probed using a novel approach categorizing the response to two stimuli:1) the MHC self restricted response, termed self +X; and 2) the allogeneic response. Using this approach, lupus mice exhibited similar in vitro Th cell pattern i.e. an absent S+X response but preserved allogeneic (termed -/+). In contrast, human lupus patients exhibited three possible response patterns, +/+, - /+ or -/- with more severe in vitro T cell impairment correlated with more severe disease. Similarly, patients with other T cell mediated conditions i.e. HIV infection or renal allograft recipients, also exhibited more severe in vitro T cell impairment with greater disease activity or greater immunosuppression respectively. The similar Th response patterns in human and murine T cell mediated conditions indicates that the underlying mechanisms involved are not disease specific but instead reflect common immune responses and validate the use of the P --> F1 model for future studies of T cell mediated conditions. These results support the use of prospective monitoring of IL-2 responses in lupus patients. Successful adaptation of this approach to the clinical setting could allow not only earlier therapeutic intervention and reduced organ damage but also earlier tapering of pharmacological agents and reduced untoward effects.

Studies of cell-mediated immune responses to influenza vaccination in systemic lupus erythematosus

OBJECTIVE

Both antibody and cell-mediated responses are involved in the defense against influenza. In patients with systemic lupus erythematosus (SLE), a decreased antibody response to subunit influenza vaccine has been demonstrated, but cell-mediated responses have not yet been assessed. This study was therefore undertaken to assess cell-mediated responses to influenza vaccination in patients with SLE.

METHODS

Fifty-four patients with SLE and 54 healthy control subjects received subunit influenza vaccine. Peripheral blood mononuclear cells and sera were obtained before and 1 month after vaccination. Cell-mediated responses to A/H1N1 and A/H3N2 vaccines were evaluated using an interferon-gamma (IFNgamma) enzyme-linked immunospot assay and flow cytometry. Antibody responses were measured using a hemagglutination inhibition test.

RESULTS

Prior to vaccination, patients with SLE had fewer IFNgamma spot-forming cells against A/H1N1 compared with control subjects and a lower frequency of IFNgamma-positive CD8+ T cells. After vaccination, the number of IFNgamma spot-forming cells increased in both patients and control subjects, although the number remained lower in patients. In addition, the frequencies of CD4+ T cells producing tumor necrosis factor and interleukin-2 were lower in patients after vaccination compared with healthy control subjects. As expected for a subunit vaccine, vaccination did not induce a CD8+ T cell response. For A/H3N2-specific responses, results were comparable. Diminished cell-mediated responses to influenza vaccination were associated with the use of prednisone and/or azathioprine. The increase in A/H1N1-specific and A/H3N2-specific antibody titers after vaccination was lower in patients compared with control subjects.

CONCLUSION

In addition to a decreased antibody response, cell-mediated responses to influenza vaccination are diminished in patients with SLE, which may reflect the effects of the concomitant use of immunosuppressive drugs. This may render these patients more susceptible to (complicated) influenza infections.

Invasive fungal infections in patients with systemic lupus erythematosus: experience from affiliated hospitals of Catholic University of Korea

The purpose of study was to determine the nature, outcomes and associated risk factors of invasive fungal infection (IFI) in patients with systemic lupus erythematosus (SLE), and compare the incidence of IFI in patients with rheumatoid arthritis (RA). A total of 1155 patients with SLE and 2004 patients with RA were retrospectively reviewed between 1992 and 2007. Twelve cases of IFI patients were identified in SLE patients (6 Aspergillus spp.; 5 Cryptococcus spp.; 1 Candida spp.). The incidence of IFI was significantly higher in patients with SLE than RA (1.04 vs. 0.15%). Among 12 patients with SLE, 10 had high Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores (≥8). The most commonly involved organ was the lung (n = 6), followed by the meninges (n = 4). Most of SLE patients with IFI (91.7%) had taken steroids prior to IFI. Three SLE patients resulted in death. Notably, these patients were all infected with Aspergillus spp. The mortality was associated with the presence of leukopenia, high anti-DNA antibodies and high SLEDAI. Collectively, IFI is more common in patients with SLE than in patients with RA. High disease activity in patients with SLE might contribute to increased risk of IFI. In addition, mortality was associated with aspergillus infection, leukopenia and high anti-DNA antibodies.

Systemic lupus erythematosus and vaccination

Patients with systemic lupus erythematosus (SLE) are frequently immunodepressed making them more vulnerable to infections. Preventive vaccination is therefore warranted but has often been withheld owing to fears of a link between infection and autoimmunity, and the possibility of inducing or exacerbating lupus after vaccination. The data published in the literature suggest that vaccination of lupus patient is safe, except for live vaccines. Their efficacy is lower than in healthy subjects but protection seems to be sufficient. But further large-scale studies are required to confirm these statements.

Infections in Systemic Connective Tissue Diseases: Systemic Lupus Erythematosus, Scleroderma, and Polymyositis/Dermatomyositis

In SLE, scleroderma, and PM/DM, infections are important causes of morbidity and mortality. This increased risk for developing infections is the result of immune abnormalities and of organ system manifestations associated with these diseases and their treatments. Common bacteria are responsible for most mild and lethal infections; however, opportunistic microorganisms cause death in some patients, particularly in those receiving high doses of corticosteroid and immunosuppressive therapy. Various viral and fungal infections also contribute to the morbidity and mortality associated with these diseases. Regardless of the cause of infections, adequate and prompt recognition and proper treatment of the infected patient are imperative. Patients who have these diseases, especially when receiving high doses of corticosteroids and immunosuppressive therapy, need to be monitored closely for these infections. This care and concern is necessary to ensure optimal patient outcomes, both in morbidity and mortality.

Influenza vaccination in systemic lupus erythematosus: safe and protective?

Patients with systemic lupus erythematosus (SLE) show decreased immune responsiveness and are vulnerable for infectious diseases, due to the underlying disease and the frequent use of immunosuppressive drugs. Influenza has a high incidence in the population and is associated with increased morbidity and mortality in immunocompromised patients. Therefore, routine influenza vaccination of SLE patients seems indicated. However, there have been concerns about the safety of influenza vaccination in SLE as vaccination was thought to activate the autoimmune response. Safety of influenza vaccination has been studied, and, as far as SLE patients with quiescent disease are concerned, it is now generally accepted that influenza vaccination is safe. Another point of concern is vaccine efficacy. In immunocompromised patients, the immunogenicity of vaccines may be reduced. In the immune response to influenza (vaccination) both humoral and cell-mediated responses are involved. In SLE, research on the immune response to influenza vaccination has focused on humoral immune responses, demonstrating a blunted humoral response. Future research should focus on cell-mediated immune responses as well, as these are important for clearing of influenza infection and are expected to be impaired in SLE. Because of the decreased immunogenicity of the current influenza vaccine in SLE, new influenza vaccination strategies should be explored to improve vaccination efficacy.

Safety and efficacy of influenza vaccination in systemic lupus erythematosus patients with quiescent disease

OBJECTIVE

to assess the safety and efficacy of influenza vaccination in patients with systemic lupus erythematosus (SLE), and to evaluate the influence of immunosuppressive drugs on the immune response.

METHODS

SLE patients (n=56) and healthy controls (n=18) were studied. All patients had quiescent disease (SLE disease activity index<or=5). Four patient groups were defined on the basis of their drug use: (1) no drug treatment; (2) hydroxychloroquine treatment; (3) azathioprine treatment; (4) prednisone treatment. Participants received trivalent influenza subunit vaccine during October/November 2003. Disease activity scores and side effects were recorded. Antibody titres against influenza virus were measured before and 30 days after vaccination using the haemagglutination inhibition assay.

RESULTS

Influenza vaccination did not result in changes in disease activity and was well tolerated. SLE patients had fewer seroconversions or fourfold titre rises for A/H1N1 (p<0.001) and A/H3N2 (p<0.001) than healthy controls, while for B/Hong Kong the difference was of borderline significance (p=0.051). With regard to immunosuppressive treatment, fewer SLE patients using azathioprine developed fourfold titre rises against A/H3N2 (p=0.041), and fewer achieved titres of >or=40 against A/H3N2 (p=0.030) compared with the other patient groups.

CONCLUSIONS

Influenza vaccination in SLE patients with quiescent disease is safe but is less effective than in controls. Use of azathioprine was associated with a trend to decreased vaccination efficacy.

EBV and systemic lupus erythematosus: a new perspective

We have proposed that EBV uses mature B cell biology to access memory B cells as a site of persistent infection. A central feature of this model is that EBV adapts its gene expression profile to the state of the B cell it resides in and that the level of infection is stable over time. This led us to question whether changes in the behavior or regulation of mature B cells would alter the state of EBV persistence. To investigate this, we studied the impact of systemic lupus erythematosus (SLE), a disease characterized by immune dysfunction, on EBV infection. We show that patients with SLE have abnormally high frequencies of EBV-infected cells in their blood, and this is associated with the occurrence of SLE disease flares. Although patients with SLE have frequencies of infected cells comparable to those seen in immunosuppressed patients, in SLE the effect was independent of immunosuppressive therapy. Aberrant expression of viral lytic (BZLF1) and latency (latency membrane proteins 1 and 2a) genes was also detected in the blood of SLE patients. We conclude that the abnormal regulation of EBV infection in SLE patients reflects the sensitivity of the virus to perturbation of the immune system.

Lymphocytopenia in lupus erythematosus: close in vivo association to autoantibodies targeting nuclear antigens

BACKGROUND

Leukopenia and lymphopenia are typical features of lupus erythematosus (LE) and correlate with elevated disease activity and higher grades of systemic involvement. Antilymphocyte antibodies are regarded as the most likely rationale for the decreased cell numbers; however, their relevance has not been confirmed so far.

OBJECTIVES

Previous investigations at our department have shown a significant correlation between diminished lymphocyte numbers and the presence of antinuclear antibodies (ANA). We wanted to achieve a better understanding of this phenomenon.

METHODS

We performed a detailed analysis of autoantibodies and peripheral leucocyte subsets in 82 patients with different subtypes of LE. Leucocyte subsets were measured using flow cytometry (FACScan; Becton Dickinson, Franklin Lakes, NJ, USA.); autoantibodies were detected by indirect immunofluorescence and by enzyme-linked immunosorbent assay.

RESULTS

A significant association (P < 0.05) between specific antibodies targeting nuclear antigens (SSA/Ro-52, SSB/La, snRNPs) and lymphocytopenia was found.

CONCLUSIONS

We suppose that some of these autoantibodies might have an antilymphocyte effect. Apoptosis induction by specific antinuclear antibodies has already been described earlier, but to the best of our knowledge this is the first study presenting a strong indication of a possible interaction between these antibodies and lymphocyte subsets in vivo.

Functional and molecular aspects of transient T cell unresponsiveness: role of selective interleukin-2 deficiency

Defects of T cell (Tc) proliferation have been demonstrated in several autoimmune diseases. Detailed mechanisms governing activation and proliferation of Tc are still not completely known. Here we show that under certain conditions human peripheral blood lymphocytes, once activated by anti-CD3, fail to respond to a subsequent restimulation via the Tc-receptor. Peripheral blood mononuclear cells (PBMC) were preactivated by anti-CD3 for 96 h following restimulation by anti-CD3, interleukin (IL)-2 and other mitogens. In control experiments unstimulated PBMC were incubated in medium alone. Immunophenotypes were analysed by flow cytometry. Cytokine production was determined by reverse transcription-polymerase chain reaction and intracellular signalling protein contents of Tc were compared by Western blotting. Furthermore, apoptosis was detected by terminal deoxyribose transferase-mediated deoxyuridine triphosphate nick end labelling assay. Unstimulated PBMC proliferate well after subsequent stimulation with anti-CD3, whereas IL-2 induces only limited proliferation. In contrast, preactivated cells respond only minimally to restimulation with anti-CD3, but IL-2 induces a marked proliferation. Both preactivated and unstimulated Tc respond well to restimulation by phytohaemagglutinin (PHA). In contrast, preactivated Tc show only a weak response to concanavalin A. Interestingly, when cells have been allowed to rest for 168 h, the responsiveness of preactivated Tc is restored. Immunoblots reveal that preactivated cells have a higher intracellular content of zeta-chain and p56lck. No differences are found concerning apoptosis after restimulation with anti-CD3 or the expression of ERK 1/2. The unresponsiveness to restimulation is due to an impairment of the transcription of the IL-2 gene and this defect is temporary. Despite the lack of proliferation, preactivated Tc phenotypically maintain an intermediate stage of activation. These data show how the same cell population can change its functional phenotype into a non-responder state.

Lupus manifestations in severe combined immunodeficient (SCID) mice and in human/mouse radiation chimeras

The objective of this study was to develop a human lupus model. To this end we have established and compared two models: (1) severe combined immunodeficient (SCID) mice reconstituted with peripheral blood lymphocytes (PBL) of either systemic lupus erythematosus (SLE) patients or healthy controls and (2) lethally irradiated BALB/c mice radioprotected with bone marrow of SCID mice, to which human PBL were transferred (human/mouse chimera). Engraftment was successful in most (78.4%) recipient mice as determined by the levels of human IgG measured. In about 50% of either SCID mice or human/mouse chimeras that were successfully engrafted with PBL of SLE patients, significant anti-dsDNA autoantibodies, mostly of the IgG1 and IgG2 isotypes, were determined. Interestingly, in a significant number (84.5%) of recipients of PBL of the healthy controls, anti-dsDNA antibodies were observed as well, suggesting that PBL of at least some of the healthy controls have the potential to develop SLE-associated autoantibodies under the appropriate stimulatory conditions. Glomerular immune deposits (human IgG, mouse C3) were detected in 70-80% of SCID mice with human DNA specific antibodies and in a third of the human/mouse chimeras. Thus, SLE serology and glomerular pathology were reproducibly demonstrated in two models of human SLE. These models should allow the evaluation of potential therapies for the treatment of lupus patients.

Modulation of autoreactive responses of peripheral blood lymphocytes of patients with systemic lupus erythematosus by peptides based on human and murine anti-DNA autoantibodies

Two peptides, based on the sequences of the complementarity-determining regions (CDR) 1 and 3 of a pathogenic murine monoclonal anti-DNA autoatibody that bears the 16/6 idiotype (Id), were shown to either prevent or treat an already established systemic lupus erythematosus (SLE) in two murine models of lupus. Two additional peptides based on the human monoclonal anti-DNA, 16/6 Id were synthesized. This study was undertaken in order to investigate the ability of the CDR-based peptides to immunomodulate SLE-associated responses of peripheral blood lymphocytes (PBL) of SLE patients. PBL of 24 of the 62 SLE patients tested proliferated in vitro following stimulation with the human 16/6 Id. Peptides based on the CDRs of both the human and murine anti-DNA autoantibodies inhibited efficiently and specifically the 16/6 Id-induced proliferation and IL-2 production. The latter inhibitions correlated with an up-regulated production (by 2.5-3.5-fold) of the immunosuppressive cytokine, TGF-beta. Overall, the results of our study demonstrate that the CDR-based peptides are capable of down-regulating in vitro autoreactive T cell responses of PBL of SLE patients. Thus, these peptides are potential candidates for a novel specific treatment of SLE patients.

Infections in systemic connective tissue diseases: systemic lupus erythematosus, scleroderma, and polymyositis/dermatomyositis

In SLE, scleroderma, and PM/DM, infections are important causes of morbidity and mortality. This increased risk of developing infections is the result of immune abnormalities and of organ system manifestations associated with these diseases and their treatments. Common bacteria are responsible for most mild and lethal infections; however, opportunistic microorganisms cause death in some patients, particularly in those receiving high doses of corticosteroid and immunosuppressive therapy. Various viral and fungal infections also contribute to the morbidity and mortality associated with these diseases. Regardless of the cause of infections, adequate and prompt recognition and proper treatment of the infected patient are imperative. Thus, patients with these diseases, especially when receiving high doses of corticosteroids and immunosuppressive therapy, need to be monitored closely for these infections. This care and concern is necessary to ensure optimal patient outcomes, both in terms of morbidity and mortality.

Systemic lupus erythematosus in the intensive care unit

SLE causes significant morbidity and mortality by multisystem organ involvement. Infections are the leading cause of morbidity and mortality in patients with SLE. Meticulous exclusion of infection is mandatory in patients with SLE, because infections may masquerade as exacerbation of underlying disease; and the immunosuppression used to treat severe forms of exacerbation of lupus can have catastrophic consequences in patients with infections. Corticosteroids are the first-line therapy for most noninfectious complications of SLE, with various adjuvant immunosuppressive agents such as cyclophosphamide being increasingly used in combination with plasmapheresis. Some recent series have shown an improved survival rate, but this improvement needs to be confirmed by further studies. Controlled trials comparing various therapeutic options are lacking, and optimal therapy has not been defined.

A possible role of apoptosis for regulating autoreactive responses in systemic lupus erythematosus

It has been reported that apoptotic cells are increased in the peripheral blood from patients with systemic lupus erythematosus (SLE), where dysfunctions of T helper 1 (Th1) cells are known. In order to study whether apoptosis of Th1 cells is associated with the pathogenesis of SLE, early apoptotic cells in various T-cell subsets were detected using fluorescence-labeled annexin V (AnV). AnV binding was most frequently observed in CD4+CCR5+ T cells, and AnV binding rate (%) in this subset was higher in SLE than in normal controls (14.7 +/- 2.6), although that in active SLE (43.6 +/- 7.3) tended to be lower than that in inactive SLE (48.0 +/- 6.8). CD95/Fas expression was also increased in both active and inactive SLE. In some SLE patients, AnV binding rate changed in inverse proportion to titer of the serum anti-DNA antibody and in proportion to serum complement activity. These data suggest that apoptosis in Th1 cells is important in the pathogenesis of SLE and might play a role in regulating over-activation or autoreactive responses by T cells.

Infections in systemic lupus erythematosus and rheumatoid arthritis

Patients with systemic lupus erythematosus have a higher infection rate than the general population. It is estimated that at least 50% of them will suffer a severe infectious episode during the course of the disease. Improvements in the control of the disease are discussed in this article.

The mechanism by which a peptide based on complementarity-determining region-1 of a pathogenic anti-DNA auto-Ab ameliorates experimental systemic lupus erythematosus

A peptide based on complementarity-determining region (CDR)-1 of a monoclonal murine anti-DNA Ab that bears the common idiotype, 16/6Id, was synthesized and characterized. The peptide, designated pCDR1, was found to be an immunodominant T-cell epitope in BALB/c mice. The CDR1-based peptide was shown to be capable of inhibiting the in vivo priming of BALB/c mice immunized with the peptide or with the whole anti-DNA 16/6Id(+) mAbs of either mouse or human origin. We show here that administration of pCDR1 (weekly, i.v., 100 microgram/mouse) in aqueous solution for 5 weeks starting at the time of disease induction with the human 16/6Id prevented the development of clinical manifestations of experimental systemic lupus erythematosus (SLE). Further, 10 weekly injections of pCDR1 to BALB/c mice with an established experimental SLE down-regulated clinical manifestations of SLE (e.g., anti-DNA auto-Abs, leukopenia, proteinuria, immune complex deposits in the kidneys) in the treated mice. Prevention of SLE induction was shown to be associated mainly with a decrease in the levels of IL-2, INFgamma, and the proinflammatory cytokine TNFalpha. On the other hand, the secretion of the immunosuppressive cytokine TGFbeta was elevated. Amelioration of the clinical manifestations of an already established experimental SLE correlated with a dramatic decrease in TNFalpha secretion, elevated levels of TGFbeta, and immunomodulation of the Th1 and Th2 type cytokines to levels close to those observed in healthy mice.

Immune response of SLE patients to peptides based on the complementarity determining regions of a pathogenic anti-DNA monoclonal antibody

We have examined the humoral and cellular responses of SLE patients to peptides based on the complementarity-determining regions (CDR) of a monoclonal anti-DNA antibody with a major idiotype- 16/6 Id, in comparison to their responses to the whole 16/6 Id-bearing antibody. Sera of 63% of the SLE patients had antibodies that bound the 16/6 Id, 80% had antibodies to one of the CDR-based peptides, and 40% of the patients reacted with both CDRs. Sera of only a few controls reacted with either the 16/6 Id (6%) or the CDR based peptides (4%) (P < 0.01). Peripheral blood lymphocytes (PBL) of 39% of the patients proliferated in response to the 16/6 Id or to one of the CDR-based peptides (37%), while in the control group the proliferation rates were 66% to the 16/6 Id and 59% to one of the CDR-based peptides (P < 0.05). The correlation between (both) the humoral and cellular immune responses to the CDR-based peptides and to the 16/6 Id suggests the relevance of these peptides to the 16/6 Id and provides additional information on the pathogenic moiety of the latter antibody.

Small-bowel involvement in systemic lupus erythematosus: a morphometric and immunohistochemical study

BACKGROUND

We have investigated the intestinal mononuclear cell subpopulations in patients with systemic lupus erythematosus (SLE) and correlated these with the disease activity.

METHODS

Eighteen female outpatients were studied; in 10 of them lupus activity was measured with the Lupus Activity Criteria Count and the SLE Disease Activity Index. Eight patients were in lupus remission. The control group consisted of 10 healthy volunteers. Peroral jejunal biopsy was performed in all individuals, at the angle of Treitz, using a Watson capsule, under X-ray control. Histologic studies analysed the villous to crypt ratio, lamina propria cells, and intraepithelial lymphocyte count. Immunohistochemical evaluation was carried out with the indirect immunoperoxidase technique, using monoclonal antibodies against CD3, CD4, CD8, D1, D7, D9, and M1.

RESULTS

Lamina propria CD3+, CD8+, D7+, and M1+ cells from patients with SLE did not differ significantly from those of controls. CD4+ cells were decreased in all patients with SLE, especially in the clinically inactive patients. D1+ and D9+ cells were also decreased in all patients.

CONCLUSION

The finding of quantitative abnormalities in the cell-mediated immunity of the intestinal mucosa may reflect systemic defects of the immune system in SLE.