Accumulation of plasma nucleosomes upon treatment with anti-tumour necrosis factor-alpha antibodies

Circulating nucleosomes as potential biomarkers for cancer diagnosis and treatment monitoring

Nucleosomes play a crucial role in regulating gene expression through their composition and post-translational modifications. When cells die, intracellular endonucleases are activated and cleave chromatin into oligo- and mono-nucleosomes, which are then released into the body fluids. Studies have shown that the levels of nucleosomes are increased in serum and plasma in various cancer types, suggesting that analysis of circulating nucleosomes can provide an initial assessment of carcinogenesis. However, it should be noted that elevated serum nucleosome levels may not accurately diagnose certain tumor types, as increased cell death may occur in different pathological conditions. Nevertheless, detection of circulating nucleosomes and their histone modifications, along with specific tumor markers, can help diagnose certain types of cancer. Furthermore, monitoring changes in circulating nucleosome levels during chemotherapy or radiotherapy in patients with malignancies can provide valuable insights into clinical outcomes and therapeutic efficacy. The utilization of circulating nucleosomes as biomarkers is an exciting and emerging area of research, with the potential for early detection of various diseases and monitoring of treatment response. Integrating nucleosome-based biomarkers with existing ones may improve the specificity and sensitivity of current assays, offering the possibility of personalized precision medical treatment for patients.

Rituximab as possible therapy in TNF inhibitor-induced IgA vasculitis with severe renal involvement

BACKGROUND

We observe the increasing use of tumor necrosis factor (TNF) inhibitors in patients affected by chronic inflammatory diseases. These drugs provide good control of symptoms, contributing to significant improvement in the quality of life in individuals with high disease burden. On the other hand, along with their wider use and longer follow-up periods the number of reports regarding their adverse effects is also increasing. The reported complications include drug-induced vasculitis with possible kidney involvement. In the literature we can distinguish more frequently described ANCA-associated vasculitis and more rarely occurring immunoglobulin A vasculitis. Although uncommon, such complications may present with potentially life-threatening vital organ dysfunction; therefore, adequate monitoring and effective therapy are necessary.

CASE PRESENTATION

We report two cases of TNF inhibitor-induced vasculitis with severe acute worsening of renal function and significant proteinuria. The first patient was receiving golimumab therapy for ankylosing spondylitis and the second patient was treated with adalimumab for psoriasis and psoriatic arthritis. In the second case dialysis treatment was necessary and the patient presented recurrence of vasculitis after rechallenge with adalimumab. Both patients underwent renal biopsy which showed findings compatible with drug-induced IgA vasculitis and both were treated successfully with corticosteroids and rituximab.

CONCLUSIONS

To the best of our knowledge this is the first report of rituximab use in drug-induced IgA vasculitis with renal involvement. Combination of corticosteroids and rituximab can be an effective therapy in case of vasculitis with kidney failure and a preferable option for selected patients with drug-induced IgA vasculitis compared to cyclophosphamide. More studies are necessary to establish suitable short- and long-term treatment. Given the rarity of this disorder, case reports and case series can provide practical guidance until additional studies become available.

Liquid biopsies for cancer: From bench to clinic

Over the past two decades, liquid biopsy has been increasingly used as a supplement, or even, a replacement to the traditional biopsy in clinical oncological practice, due to its noninvasive and early detectable properties. The detections can be based on a variety of features extracted from tumor‑derived entities, such as quantitative alterations, genetic changes, and epigenetic aberrations, and so on. So far, the clinical applications of cancer liquid biopsy mainly aimed at two aspects, prediction (early diagnosis, prognosis and recurrent evaluation, therapeutic response monitoring, etc.) and intervention. In spite of the rapid development and great contributions achieved, cancer liquid biopsy is still a field under investigation and deserves more clinical practice. To better open up future work, here we systematically reviewed and compared the latest progress of the most widely recognized circulating components, including circulating tumor cells, cell-free circulating DNA, noncoding RNA, and nucleosomes, from their discovery histories to clinical values. According to the features applied, we particularly divided the contents into two parts, beyond epigenetics and epigenetic-based. The latter was considered as the highlight along with a brief overview of the advances in both experimental and bioinformatic approaches, due to its unique advantages and relatively lack of documentation.

Tumor necrosis factor-α inhibitor-related immune disorders

Biotechnological monoclonal antibodies and receptor antagonists capable of targeting specific inflammatory actors, such as cytokines, cytokines receptors, co-stimulatory molecules or leukocyte populations, have emerged as an alternative to conventional therapies for treating systemic inflammatory diseases with immune pathogenesis. However, there is no doubt that, with a frequency that is not exceptionally high but also not negligible, immunotherapies can favour the development of systemic and organ-specific immune-mediated disorders. It has become increasingly evident that interference with a specific immune pathway may favour the activation of opposing compensatory signalling, which may exacerbate underlying subclinical disorders or cause immune-mediated diseases completely different from the underlying disease. The 'compensatory immunological switch' has emerged primarily in patients treated with tumor necrosis factor (TNF) -α inhibitors, the first biological drugs approved for treating systemic inflammatory diseases with immune pathogenesis. In this Review, we describe the clinical features and predisposing factors of the main TNF-α inhibitor-related immune disorders, organising them into subclinical serological autoimmunity, autoimmune disorders other than those for which TNF-α inhibitors are indicated, and paradoxical reactions. We also discuss the underlying pathogenetic mechanisms and precautions for use in the therapeutic management of these patients. Better understanding of the complex phenomenon of the 'compensatory immunological switch', which TNF-α inhibitors and other biological drugs might trigger, can help not only appropriately managing immune-mediated disorders, but also better interpreting the heterogeneity of the pathogenetic mechanisms underlying certain chronic inflammatory conditions that, although different from each other, are arbitrarily placed in the context of overly generic nosological entities.

Bullous pemphigoid induced by biologic drugs in psoriasis: a systematic review

INTRODUCTION

Several therapies for psoriasis have been described as triggers of biologic-induced bullous pemphigoid (BIBP). The real incidence of BIBP in psoriatic patients is still unknown. Hence, we compilated and analyzed current literature to identify the frequency and burden of this adverse event for psoriasis patients treated with biologics.

MATERIAL AND METHOD

We systematically searched literature records involving psoriatic patients developing BIBP. Electronic searches were conducted in Pubmed, EMBASE and Scopus in April 2021. To assess the causal relationship between BP and the biologic drug, we applied the Naranjo adverse reaction probability scale and the Karch-Lasagna algorithm.

RESULTS

Our systematic review identified 586 records through the three electronic databases. We identified 15 case reports of BIBP. These cases implicated two cases induced by adalimumab, three by efalizumab, three by etanercept, six by ustekinumab, and one case by secukinumab. Mean period of latency until the BIBP developed was time 5.12 ± 3.44 weeks for TNF-α blockers, and 28.66 ± 26.27 weeks for ustekinumab (p = .09). Most of the cases were assessed as "probable" consistently in both the Naranjo scale and the Karch-Lasagna algorithm.

CONCLUSION

This work presents an accurate estimation on the frequency and burden of BIBP. Ustekinumab presents with the largest evidence of BIBP, especially in patients with previous failure to TNF-α agents. Distinct patterns in the cytokinic pathways and clinical course exist between the BP induced by TNF-α blockers and ustekinumab. A close monitoring of skin condition is highly advisable in patients receiving biologic therapies for psoriasis. Knowledge of BIBP is of great importance to determine the preventive measures and select optimal treatment options.What's already known about this topic?The widespread use of biologic drugs has led dermatologists to encounter increasing situations of biologic-induced BP (BIBP).A lack of data exists on the real incidence of BIBP in psoriatic patients.BIBP is an important adverse event to know when managing patients with psoriasis using biologics.What does this study add?This work presents an accurate estimation on the raised burden of BIBP.Ustekinumab presents with the largest evidence of BIBP, especially in patients with previous failure to TNF-α agents.Mean period of latency until the BIBP developed was time 5.12 ± 3.44 weeks for TNF-α blockers, and 28.66 ± 26.27 weeks for ustekinumab.Distinct patterns in the cytokine pathways and clinical course exist between the BP induced by TNF-α blockers and ustekinumab.A careful screening of previous history of bullous diseases and a baseline immunologic study in psoriatic patients should be advisable prior to commencing any biologic therapy.A close monitoring of skin condition is highly advisable in patients receiving biologic therapies for psoriasis.

TNF-Induced Lupus. A Case-Based Review

Nowadays, tumor necrosis factor alpha (TNFα) inhibitors have revolutionised the treatment of inflammatory arthritides by demonstrating efficacy with an acceptable toxicity profile. However, autoimmune phenomena and clinical entities have been reported ranging from an isolated presence of autoantibodies to full-blown autoimmune diseases, among them, drug-induced lupus (DIL). Case Presentation: A 62-year-old woman with rheumatoid arthritis (RA) refractory to methotrexate and prednisone, was treated with adalimumab (ADA). 4 months later, she presented acute cutaneous eruptions after sun exposure, positive ANA (1/640 fine speckled pattern), Ro (SSA) and anti-Smith (Sm) antibodies with no other clinical or laboratory abnormalities. The diagnosis of DIL was made, ADA was discontinued and she was treated successfully with prednisone plus local calcineurin inhibitors. Conclusion: Thus, we review the literature for cases of DIL development in patients treated with TNFα inhibitors. Rheumatologists should be aware of the possible adverse events and the requirement of careful clinical evaluation and monitoring.

Biologic Therapies and Autoimmune Phenomena

The use of biologic medications has represented a great advancement in the treatment of autoimmune rheumatic diseases. Despite their excellent efficacy, during the last years, a growing number of reports of autoimmune phenomena and paradoxical inflammation has emerged. These phenomena may range from the discovery of an isolated autoantibody to full-blown autoimmune diseases, organ-specific and systemic. This review has been carried out in order to underline the multitude of the potential adverse manifestations from the use of biologic medications. Thus, early recognition of specific types of autoimmune phenomena is an imperative for the physicians allowing them to have an accurate diagnosis and treatment.

Sh3bp2 Gain-Of-Function Mutation Ameliorates Lupus Phenotypes in B6.MRL-Faslpr Mice

SH3 domain-binding protein 2 (SH3BP2) is an adaptor protein that is predominantly expressed in immune cells, and it regulates intracellular signaling. We had previously reported that a gain-of-function mutation in SH3BP2 exacerbates inflammation and bone loss in murine arthritis models. Here, we explored the involvement of SH3BP2 in a lupus model. Sh3bp2 gain-of-function (P416R knock-in; Sh3bp2^KI/+) mice and lupus-prone B6.MRL-Fas^lpr mice were crossed to yield double-mutant (Sh3bp2^KI/+Fas^lpr/lpr) mice. We monitored survival rates and proteinuria up to 48 weeks of age and assessed renal damage and serum anti-double-stranded DNA antibody levels. Additionally, we analyzed B and T cell subsets in lymphoid tissues by flow cytometry and determined the expression of apoptosis-related molecules in lymph nodes. Sh3bp2 gain-of-function mutation alleviated the poor survival rate, proteinuria, and glomerulosclerosis and significantly reduced serum anti-dsDNA antibody levels in Sh3bp2^KI/+Fas^lpr/lpr mice. Additionally, B220⁺CD4⁻CD8⁻ T cell population in lymph nodes was decreased in Sh3bp2^KI/+Fas^lpr/lpr mice, which is possibly associated with the observed increase in cleaved caspase-3 and tumor necrosis factor levels. Sh3bp2 gain-of-function mutation ameliorated clinical and immunological phenotypes in lupus-prone mice. Our findings offer better insight into the unique immunopathological roles of SH3BP2 in autoimmune diseases.

Lessons for lupus from tumour necrosis factor blockade

Systemic lupus erythematosus (SLE) is a systemic non-organ specific autoimmune disease associated with multiple autoantibodies targeting autoantigens from the nucleus. Given the complex pathophysiology of SLE and the role of TNF alpha in that disease, modulation of TNF alpha (in SLE or non-SLE patients) using TNF blockers could either be detrimental or beneficial in some patients. In this review we will focus on lupus autoantibodies and clinical manifestations after TNF blockade in SLE patients and conversely on drug-induced-SLE in non-SLE patients. Some hypotheses regarding the mechanism of induction of autoantibodies in RA patients treated with TNF blockers are proposed.

Adalimumab-Induced Cutaneous Lupus Erythematosus in a 16-Year-Old Girl with Juvenile Idiopathic Arthritis

Tumor necrosis factor α (TNF-α) antagonists are used in the treatment of numerous autoimmune conditions. Adalimumab is the first monoclonal antibody to TNF-α and is used to treat juvenile idiopathic arthritis. A growing body of literature associates anti-TNF-α therapies with several adverse dermatologic manifestations, including drug-induced lupus erythematosus (LE). We describe a case of cutaneous LE in a 16-year-old girl treated with adalimumab for juvenile idiopathic arthritis. The temporal association between her presenting symptoms and adalimumab initiation and gradual improvement after stopping biologic therapy suggest adalimumab-induced cutaneous LE. With increasing use of anti-TNF therapies in children, the potential for drug-induced LE should not be overlooked.

Decreased serum cell-free DNA levels in rheumatoid arthritis

Purpose

Recent studies have demonstrated that serum/plasma DNA and RNA molecules in addition to proteins can serve as biomarkers. Elevated levels of these nucleic acids have been found not only in acute, but also in chronic conditions, including autoimmune diseases. The aim of this study was to assess cell-free DNA (cfDNA) levels in sera of rheumatoid arthritis (RA) patients compared to controls.

Methods

cfDNA was extracted from sera of patients with early and established RA, relapsing-remitting multiple sclerosis patients (RRMS) and healthy subjects, and its concentration was determined by quantitative PCR using two amplicons, Alu115 and β-actin205, corresponding to Alu repetitive elements and the β-actin single-copy gene, respectively. Serum DNase activity was measured by a single radial enzyme diffusion method.

Results

Reduced levels of cfDNA were observed in patients with established RA in comparison with healthy controls, early RA patients and RRMS patients. There were no significant differences in cfDNA concentration between healthy controls, early RA and RRMS patients. Total DNase activity appeared to be similar in the sera of all tested groups.

Conclusions

Our results demonstrate that cfDNA levels are strongly reduced in the sera of established RA patients, which is not caused by changes in DNase activity. Measurement of cfDNA can distinguish established RA patients from early RA patients. Thus, cfDNA may serve as a biomarker in RA.

Electronic supplementary material

The online version of this article (doi:10.1007/s13317-015-0066-6) contains supplementary material, which is available to authorized users.

Drug-induced glomerular disease: immune-mediated injury

Drug-induced autoimmune disease was initially described decades ago, with reports of vasculitis and a lupus-like syndrome in patients taking hydralazine, procainamide, and sulfadiazine. Over the years, multiple other agents have been linked to immune-mediated glomerular disease, often with associated autoantibody formation. Certain clinical and laboratory features may distinguish these entities from their idiopathic counterparts, and making this distinction is important in the diagnosis and management of these patients. Here, drug-induced, ANCA-associated vasculitis, drug-induced lupus, and drug-associated membranous nephropathy are reviewed.

Mechanisms of tumor necrosis factor α antagonist-induced lupus in a murine model

OBJECTIVE

Tumor necrosis factor α (TNFα) antagonists are effective for treating rheumatoid arthritis and other inflammatory diseases, but their use can be complicated by the development of lupus-like phenomena. This study was undertaken to investigate the role of TNFα in a murine model of lupus.

METHODS

Toll-like receptor 7 (TLR-7) ligand-driven lupus was induced by injection of pristane into C57BL/6 (B6) mice deficient in TNFα (TNFα(-/-) ) or TNFα-intact B6 mice as wild-type controls. Autoantibody and type I interferon (IFN) production was measured in each group of mice, and the effects of the presence or absence of TNFα on type I IFN-producing plasmacytoid dendritic cells (PDCs), Ly-6C(high) monocytes, and TNFα-producing neutrophils were determined.

RESULTS

TNFα(-/-) mice did not spontaneously develop autoantibodies or clinical manifestations of lupus, suggesting that TNFα deficiency alone is insufficient to cause lupus. Although the levels of type I IFN were comparable between untreated TNFα(-/-) and wild-type control mice, untreated TNFα(-/-) mice had increased circulating levels of PDCs and PDC-like cells, which enhanced the potential for production of type I IFN. When treated with pristane, TNFα(-/-) mice developed more severe lupus compared to pristane-treated controls, characterized by increased levels of anti-Sm/RNP autoantibodies, type I IFN, PDCs, and peritoneal inflammatory (Ly-6C(high) ) monocytes. In pristane-treated TNFα(-/-) mice, the numbers of neutrophils, a cell type that promotes resolution of inflammation, were decreased considerably, whereas the responses of inflammatory monocytes and PDCs and the production of type I IFN were increased and prolonged.

CONCLUSION

Low levels of TNFα will increase the number of circulating PDCs in mice, thereby enhancing the potential to produce type I IFN. However, this does not necessarily lead to type I IFN production or autoimmunity unless there is concomitant exposure to endogenous TLR-7 ligands, which are released from dead cells following pristane treatment. In humans, the rate of clearance of dead cells, along with the levels of TNFα, may influence who will develop lupus following treatment with TNFα inhibitors.

Adalimumab-induced lupus serositis

A 61-year-old man presented with a 1-month history of breathlessness, chest pain and lethargy. He had been taking adalimumab for ankylosing spondylitis for 2 years. Pleural and pericardial effusions were both found. A video-assisted thorascopic (VATS) pleural and lung biopsy were performed. The pleural pathology showed eosinophils, acute inflammatory cells and lymphoid aggregates. The patient was positive for antinuclear, antidouble-stranded and antihistone antibodies consistent with drug-induced lupus due to adalimumab. His serositis resolved on withdrawal of the drug. Drug-induced lupus can occur as a consequence of anti-TNF-α agents from induction of autoimmunity in a predisposed host.

Drug-induced lupus: Including anti-tumour necrosis factor and interferon induced

Drug-induced lupus erythematosus is defined as a syndrome with clinical and serological features similar to systemic lupus erythematosus that is temporally related to continuous drug exposure and which resolves after discontinuation of this drug. More than 90 drugs, including biological modulators such as tumour necrosis factor-α inhibitors and interferons, have been identified as likely ‘culprits’. While there are no standard diagnostic criteria for drug-induced lupus erythematosus, guidelines that can help to distinguish drug-induced lupus erythematosus from systemic lupus erythematosus have been proposed and several different patterns of drug-induced lupus erythematosus are emerging. Distinguishing drug-induced lupus erythematosus from systemic lupus erythematosus is important because the prognosis of drug-induced lupus erythematosus is usually good when the drug is withdrawn. This review discusses the differences between drug-induced lupus erythematosus and systemic lupus erythematosus, the mechanisms of action of drug-induced lupus erythematosus and drugs that are usually associated with drug-induced lupus erythematosus, with particular focus on the biological treatments.

Broad range of adverse cutaneous eruptions in patients on TNF-alpha antagonists

Biologic therapies targeting tumor necrosis factor (TNF)-alpha have become a mainstay in the management of a number of autoimmune diseases. We report a series of adverse skin eruptions in six patients (four females, two males, age: 21-58 years, mean: 39) receiving 4 months to 10 years (mean 3.1 years) of anti-TNF-alpha therapies (infliximab, n = 4; adalimumab, n = 1 or etanercept, n = 1). The following drug-associated diagnoses were made in eight skin biopsies performed at Massachusetts General Hospital between 3/2007 and 10/2010: pustular folliculitis, psoriasis, interface dermatitis, neutrophilic eccrine hidradenitis, Sweet's syndrome, lupus, vasculitis and palmoplantar pustulosis. The descriptions of neutrophilic eccrine hidradenitis-like and Sweet's-like hypersensitivity eruptions induced by anti-TNF-alpha therapies are the first such cases described in the literature. Each cutaneous eruption improved or resolved with switching to a different TNF-alpha inhibitor, discontinuation of the anti-TNF-alpha agent, and/or topical or systemic steroids. There was a clear chronologic relationship with, and clinical remission upon withdrawal or steroid suppression of the anti-TNF-alpha agents. The mechanism for such diverse cutaneous eruptions among this class of medications remains poorly understood. The cutaneous adverse reaction profile of TNF-alpha inhibitors is broad and should be considered in the histopathologic differential in this clinical setting.

Factors associated with the loss of response to infliximab in patients with Crohn's disease

BACKGROUND AND AIMS

The efficacy of infliximab (IFX) has validated the role of TNF-α in the immunopathogenesis of Crohn's disease (CD). However, antibodies to IFX emerge, which impair its efficacy. This study investigated factor(s) associated with the loss of response (LOR) to IFX and how IFX non-responders may be treated.

METHODS

Seventy-four patients, 36 IFX responders (GI) and 38 with LOR (GII) were included. Trough IFX level, CD activity index (CDAI) and immunological markers during IFX maintenance therapy were measured. Adsorptive granulocyte/monocyte apheresis (GMA) was applied to patients with LOR.

RESULTS

The durations of CD, 9.3 ± 5.5 yr and IFX therapy, 3.4 ± 2.0 yr in GII were longer vs GI (P=0.02, P=0.01). Similarly, C-reactive protein (P<0.0001) and CDAI (P<0.0001) in GII were higher. The median trough IFX was 4.7 μg/mL in GI and 8.4 μg/mL in GII, while the dose frequency was 8 weeks in GI and 4 weeks in GII. Soluble interleukin-2 receptor (sIL-2R) was higher in GII vs GI (P<0.001). Seropositive rates of anti-nuclear antibodies (ANA) and circulating immune complexes (CIC) in GII were 50.0% and 68.4%, significantly higher vs GI (P<0.05, P<0.01). Patients with LOR duration <1.5 yr showed higher CDAI and sIL-2R (P<0.05) vs patients with LOR duration <1.5 yr. Fifteen GII patients received GMA plus IFX combination and 46.7% responded. IL-10 increased in GMA-responders (P<0.05), while CIC and ANA decreased (P=0.0237, P=0.0463).

CONCLUSIONS

Patients with LOR to IFX had dysregulated immune response despite uncompromised trough IFX level. Further, inadequate T-cell differentiation by IFX was suggested. GMA appeared to benefit LOR patients by immunoregulation.

Apoptosis as a mechanism of action of tumor necrosis factor antagonists in rheumatoid arthritis

Tumor necrosis factor (TNF) antagonists are drugs developed to block endogenous TNF, an essential proinflammatory molecule with a central role in the pathogenesis of rheumatoid arthritis (RA). Although extensive studies have been performed concerning the mode of action of TNF-blocking agents, there are still many unresolved questions and potential differences between different TNF-blocking drugs. One unresolved issue is to what extent apoptosis is affected by TNF blockade in RA. We provide an overview of studies that have investigated the proapoptotic effect of different anti-TNF drugs in RA, searching for a unified interpretation of somewhat contradictory data.

Infliximab exerts no direct hepatotoxic effect on HepG2 cells in vitro

BACKGROUND

Infliximab-induced hepatotoxicity is reported in several case studies involving patients with inflammatory bowel disease (IBD) and a direct hepatotoxic effect has been proposed.

OBJECTIVE

The aim of this study was to determine the direct in vitro toxicity of infliximab. As a proof of principle the in vitro toxicity of thiopurines and methotrexate was also determined.

METHODS

Cell survival curves and the half maximal inhibitory concentrations (IC(50)) were obtained after 24, 48 and 72 h of incubation in HepG2 cells with the IBD drugs azathioprine, 6-mercaptopurine, 6-thioguanine, methotrexate or infliximab by using the WST-1 cytotoxicity assay.

RESULTS

No in vitro hepatotoxicity in HepG2 cells was seen with infliximab, while concentration-dependent cytotoxicity was observed when HepG2 cells were incubated with increasing concentrations of azathioprine, 6-mercaptopurine and 6-thioguanine.

CONCLUSION

Infliximab alone or given in combination with azathioprine showed no direct hepatotoxic effect in vitro, indicating that the postulated direct hepatotoxicity of infliximab is unlikely.

Anti-nuclear antibody positivity and the use of certolizumab in inflammatory bowel disease patients who have had arthralgias or lupus-like reactions from infliximab or adalimumab

OBJECTIVE

Tumor necrosis factor (TNF) inhibitors can be used to treat inflammatory bowel disease (IBD) but may lead to anti-nuclear antibody (ANA) positivity and lupus-like reactions. Because of its unique structure, certolizumab has lower rates of these complications. We sought to investigate whether patients who have had lupus-like reactions to infliximab or adalimumab would be able to tolerate certolizumab.

METHODS

We performed a retrospective analysis on the 23 patients at the Roberts Inflammatory Bowel Disease Center who received certolizumab for the treatment of Crohn's disease from March 2008 to June 2009. We identified 6 patients who were switched to this drug because of lupus-like reactions from prior anti-TNF therapy and had documented ANA after the reaction and prior to certolizumab initiation. We then rechecked the ANA status after certolizumab initiation.

RESULTS

Five out of 6 patients had a resolution of their arthralgias or lupus-like symptoms after being switched to certolizumab (P < 0.001). Of the 4 patients who were ANA positive after receiving infliximab or adalimumab, 2 became ANA negative after induction with certolizumab (P = 0.17). There was no difference in Harvey Bradshaw index scores (10.3 vs. 9.8) pre-certolizumab and post-certolizumab (P = 0.73).

CONCLUSION

Nearly all patients experienced relief from their lupus-like symptoms with certolizumab and 2 out of 4 patients reversed their ANA positivity. While future investigation is warranted, patients who have lupus-like reactions from infliximab or adalimumab may benefit from switching to certolizumab.

TNF alpha antagonist-induced lupus-like syndrome: report and review of the literature with implications for treatment with alternative TNF alpha antagonists

BACKGROUND

  In patients with various autoimmune and rheumatic diseases, a drug-induced lupus-like syndrome (DILS) has been reported with the use of adalimumab, cerrolizumab pegol, etanercept, and infliximab.

OBJECTIVE

  To review clinical characteristics of patients who develop tumor necrosis factor (TNF) alpha antagonist-induced lupus-like syndrome (TAILS) and review implications for further TNF alpha antagonist therapy.

MATERIALS AND METHODS

 We describe a 62-year-old woman with rheumatoid arthritis who developed a pruritic photo-distributed rash two months after the initiation of etanercept therapy. Her skin biopsy showed lupus erythematosus, and she had positive serum ANA, anti-Sjogren's syndrome A (SSA)/Ro, and anti-Sjogren's syndrome B (SSB)/La antibodies. Her symptoms resolved after discontinuation of the drug, topical and systemic corticosteroids, and hydroxychloroquine sulfate. Subsequently, her rheumatoid arthritis was treated with golimumab for six months without recurrence of skin lesions. Published reports of individuals who have developed TAILS and those who have continued treatment with alternative TNF alpha antagonists are reviewed.

RESULTS

  TAILS is most commonly associated with the use of etanercept and infliximab. It occurs most often in women in the fifth decade of life. Onset of symptoms ranges from less than one month to more than four years. Syndrome-associated cutaneous lesions and induction of autoantibodies are common. There is no definitively established mechanism of pathogenesis. Treatment can include discontinuation of the drug, corticosteroids, immunosuppressives, and hydroxychloroquine sulfate. To date, 10 patients with TAILS have continued therapy with an alternative TNF alpha antagonist without recurrence of lupus symptoms.

CONCLUSIONS

Development of a DILS after one TNF alpha antagonist does not preclude continued treatment with an alternative TNF alpha antagonist.

Anti-TNF-induced lupus

The use of protein-based anti-TNF-alpha therapies such as antibodies and soluble TNF-alpha receptors is commonly associated with the induction of autoantibodies, whereas anti-TNF-induced lupus (ATIL) is rare. ATIL can occur with any of the available TNF inhibitors, but the frequency and clinical characteristics of ATIL vary between different drugs. Cutaneous, renal and cerebral involvement as well as dsDNA antibodies are more common in ATIL compared to classical drug-induced lupus (DIL), suggesting different pathogenic mechanisms of ATIL and DIL. True ATIL must be clinically differentiated from mixed CTD, SLE or overlap syndromes unmasked, but not induced, by anti-TNF-alpha treatment of unclassified polyarthritis. The pathogenesis of ATIL is still unknown. Concomitant immunosuppression can reduce autoantibody formation in ATIL, and withdrawal of anti-TNF-alpha therapy usually leads to resolution of symptoms. Steroids and/or immunosuppressive therapy may be required in severe cases.

Clinical use of circulating nucleosomes

Nucleosomes, complexes of DNA and histone proteins, are released from dying and stressed cells into the blood circulation. Concentrations of circulating nucleosomes in plasma and serum are frequently found to be elevated in various cancers, and also in such acute conditions as stroke, trauma, and sepsis as well as in autoimmune diseases. The first part of this review focuses on the structural and functional properties of nucleosomes, the potential sources of nucleosome release into the circulation, the metabolism of circulating nucleosomes, and their pathophysiological role in disease. It goes on to describe the relevance of circulating nucleosomes in the diagnosis and prognosis of non-malignant conditions such as sepsis, stroke, and autoimmune disease. Finally, it describes the clinical value of nucleosomes in the diagnosis, staging, prognosis, and monitoring of therapy in cancer; in particular, their potential as a new diagnostic tool for the early estimation of response to cytotoxic cancer therapy is emphasized.

Analysis of apoptosis in peripheral blood and synovial tissue very early after initiation of infliximab treatment in rheumatoid arthritis patients

OBJECTIVE

Infliximab treatment results in a decrease in synovial cellularity as early as 48 hours after initiation of therapy in patients with rheumatoid arthritis (RA). This study was undertaken to investigate whether infliximab induces apoptosis within the first 24 hours after infusion.

METHODS

The percentage of apoptotic cells was determined by flow cytometry in blood drawn from 21 patients directly before, 1 hour after, and 24 hours after infliximab infusion. Synovial tissue samples obtained before, 1 hour after (n = 5), or 24 hours after (n = 5) initiation of therapy were subjected to immunohistochemistry to detect active caspase 3 and to TUNEL assay and electron microscopy to detect apoptosis. In addition, plasma levels of nucleosomes (generated during apoptosis) and C4b/c (an indicator of complement activation) were measured.

RESULTS

There were no signs of apoptosis induction in peripheral blood monocytes or lymphocytes after infliximab treatment. Circulating lymphocyte counts were increased within 1 hour after infusion (P < 0.05). There was no definite evidence of apoptosis induction in the synovium, except in 1 patient 24 hours after the infliximab infusion. Consistent with these results, there was no increase in nucleosome levels nor were there signs of complement activation.

CONCLUSION

Our findings indicate that the rapid decrease in synovial cellularity observed after initiation of anti-tumor necrosis factor antibody therapy cannot be explained by apoptosis induction at the site of inflammation. It is tempting to speculate that the striking effects on synovial inflammation may be explained by other mechanisms, such as decreased migration toward the synovial compartment and reduced retention in the inflamed synovium.

Drug-induced lupus erythematosus

Drug-induced lupus erythematosus (DILE) is defined as a lupus-like syndrome temporally related to continuous drug exposure which resolves after discontinuation of the offending drug. There are currently no standard diagnostic criteria for DILE and the pathomechanisms are still unclear. Similarly to idiopathic lupus, DILE can be diveded into systemic (SLE), subacute cutaneous (SCLE) and chronic cutaneous lupus (CCLE). Systemic DILE is characterized by typical lupus-like symptoms including skin signs, usually mild systemic involvement and a typical laboratory profile with positive antinuclear and anti-histone antibodies, while anti-double strand (ds) DNA and anti-extractable nuclear antigens antibodies are rare. High risk drugs include hydralazine, procainamide and isoniazid. Drug-induced SCLE is very similar to idiopathic SCLE in terms of clinical and serologic characteristic, and it is more common than the systemic form of DILE. Drugs associated with SCLE include calcium channel blockers, angiotensin-converting enzyme inhibitors, interferons, thiazide diuretics and terbinafine. Drug-induced CCLE is very rarely reported in the literature and usually refers to fluorouracile agents or non steroidal anti-inflammatory drugs. Recently, cases of DILE have been reported with anti-TNFalpha agents. These cases present with disparate clinical features including arthritis/arthralgia, skin rash, serositis, cytopenia and variable laboratory abnormalities. DILE to anti-TNFalpha agents differs in several ways to classic DILE. The incidence of rashes is higher compared to classical systemic DILE. In most cases of classic DILE visceral involvement is rare, whereas several cases of anti-TNFalpha DILE with evidence of renal disease have been reported. Low serum complement levels as well as anti-extractable nuclear antigen antibodies and anti-dsDNA antibodies are rarely present in classic DILE, whereas they are reported in half the cases of anti-TNFalpha DILE; in contrast, anti-histone antibodies are described in classic DILE more often than in anti-TNFalpha DILE. Recognition of DILE in patients receiving anti-TNFalpha therapy can be difficult due to the symptoms of their underlying disease. A temporal association (months to years) of the offending drug with characteristic or suggestive symptoms, and resolution of symptoms on drug withdrawal is the best evidence for this diagnosis of DILE.

Tumor necrosis factor-alpha inhibitor-induced lupus-like syndrome presenting as fever of unknown origin in a liver transplant recipient: case report and concise review of the literature

A 44-year-old man was admitted to the hospital with fever and myalgias 11 years after deceased donor liver transplantation for primary sclerosing cholangitis associated with ulcerative colitis. During hospitalization, he developed anemia, thrombocytopenia, and serositis. An extensive series of investigations eliminated infectious, malignant, thrombotic, and metabolic causes of fever. Because the patient had received tumor necrosis factor (TNF)-alpha inhibitor therapy for refractory pouchitis, a diagnosis of TNF-alpha inhibitor-induced lupus-like syndrome was considered. Further evaluation revealed an elevated antinuclear antibody titer of 1:640. Following discontinuation of the TNF-alpha inhibitor and a brief course of systemic corticosteroid therapy, the patient's symptoms resolved. TNF-alpha inhibitor therapy is increasingly used for posttransplantation management of inflammatory bowel disease, and drug-induced lupus is an increasingly recognized complication of such therapy. Because TNF-alpha inhibitor-induced lupus may not be recognized due to its nonspecific symptoms and the potential coexisting illnesses present in transplant recipients, a high index of suspicion is required.

Exposure to nuclear antigens contributes to the induction of humoral autoimmunity during tumour necrosis factor alpha blockade

OBJECTIVE

Type I interferons and apoptotic particles contribute to antinuclear autoimmunity in experimental models. This study assessed whether similar mechanisms contribute to break peripheral B-cell tolerance in humans by studying the induction of antinuclear antibodies by tumour necrosis factor blockade in spondyloarthritis.

METHODS

40 spondyloarthritis patients treated with infliximab or etanercept and 20 renal cell carcinoma patients treated with sorafenib were studied. Serum antinucleosome IgM and nucleosomes were measured by ELISA. Type I interferon serum activity was measured using a functional reporter cell assay. Synovial apoptosis was assessed by terminal transferase nick end-labelling (TUNEL) assay and anti-active caspase-3 immunostaining. Complement was measured by nephelometry.

RESULTS

Despite a similar clinical improvement and reduction of synovial inflammation, antinucleosome IgM were induced by infliximab but not etanercept. This induction did not correlate with type I interferon activity, which was transiently downmodulated by infliximab but persistently upregulated by etanercept. In contrast, antinucleosome IgM levels did correlate with serum nucleosome levels, which were significantly upregulated by infliximab but not by etanercept treatment. This increase in serum nucleosome levels was not directly related to massive cell death, but rather to a decrease of complement 3 and 4 serum levels during infliximab treatment.

CONCLUSION

Infliximab and etanercept have a differential effect on both type I interferon activity and nucleosome levels. Only elevated serum nucleosomes relate to the induction of antinucleosome antibodies after infliximab treatment.

Tumor necrosis factor antagonist mechanisms of action: a comprehensive review

During the past 30 years, elucidation of the pathogenesis of rheumatoid arthritis, Crohn's disease, psoriasis, psoriatic arthritis and ankylosing spondylitis at the cellular and molecular levels has revealed that these diseases share common mechanisms and are more closely related than was previously recognized. Research on the complex biology of tumor necrosis factor (TNF) has uncovered many mechanisms and pathways by which TNF may be involved in the pathogenesis of these diseases. There are 3 TNF antagonists currently available: adalimumab, a fully human monoclonal antibody; etanercept, a soluble receptor construct; and infliximab, a chimeric monoclonal antibody. Two other TNF antagonists, certolizumab and golimumab, are in clinical development. The remarkable efficacy of TNF antagonists in these diseases places TNF in the center of our understanding of the pathogenesis of many immune-mediated inflammatory diseases. The purpose of this review is to discuss the biology of TNF and related family members in the context of the potential mechanisms of action of TNF antagonists in a variety of immune-mediated inflammatory diseases. Possible mechanistic differences between TNF antagonists are addressed with regard to their efficacy and safety profiles.

Anti-nucleosome antibodies as prediction factor of development of autoantibodies during therapy with three different TNFalpha blocking agents in rheumatoid arthritis

Anti-nucleosome antibodies have a role in the diagnosis and follow-up of systemic lupus erythematosus (SLE) and have a possible correlation with SLE activity and with kidney and hematological involvement. The aim of our study was to detect in 91 patients with rheumatoid arthritis (RA) the positivity of anti-nucleosome antibodies during therapy with three different TNFalpha blocking agents and to underline the possible correlation with the development of antinuclear autoantibodies (ANA) and anti-dsDNA autoantibodies. We detected anti-nucleosome antibodies, ANA, and anti-dsDNA during therapy with three different TNFalpha blocking agents at T-0 and after 12 and 24 weeks of treatment, respectively. Anti-nucleosome antibodies (IgG class) were analyzed by ELISA technique (Orgentec Diagnostika GmbH, Mainz, Germany), ANA both by indirect immunofluorescence (IIF) technique on Hep-2 (Scimedx, USA) and by ELISA (Autoimmune EIA ANA screening test Bio-Rad Laboratories, CA, USA), and anti-dsDNA (IgG and IgM classes) by ELISA (Kallestad, Bio-Rad Laboratories, CA, USA) and confirmed by IIF on Crithidia luciliae (ImmunoConcepts N.A., Sacramento, CA, USA). We observed 19 patients on infliximab treatment at 3 mg/kg every 8 weeks, 43 patients on etanercept treatment at 25 mg twice a week, and 29 patients on adalimumab treatment at 40 mg every other week. At baseline, we observed positivity as follow: in the group of patients treated with infliximab-anti-nucleosome 1/19 (5.26%), ANA 3/19 (15.7%), anti-dsDNA 1/19 (5.26%); in the group treated with etanercept--anti-nucleosome 2/43 (4.65%), ANA 1/43 (2.43%), anti-dsDNA 0/43; and in the group treated with adalimumab--anti-nucleosome 2/29 (6.89%), ANA 1/29 (3.44%), anti-dsDNA 0/29. The results at 12 weeks for the three autoantibodies were: for infliximab--3/19 (15.7%), 10/19 (52.6%), 2/19 (10.5%); for etanercept--3/43 (6.9%), 10/43 (23.2%), 1/43 (2.32%); and for adalimumab--3/29 (10.3%), 4/29 (13.7%), 1/29 (3.4%). At 24 weeks, the results were for infliximab 6/19 (31.5%), 12/19 (63.1%), 2/19 (10.5%); for etanercept 11/43 (25.5%), 22/43 (51.1%), 2/43 (4.65%); and for adalimumab 4/29 (13.7%), 13/29 (44.8%), 1/29 (3.4%). We observed a concordance anti-nucleosome/ANA antibodies of 85.5% (p < 0.001). Our data showed a concordance between anti-nucleosome antibodies and ANA positivity in patients with RA during therapy with TNFalpha blocking agents. The induction of autoantibodies positivity is different for each TNFalpha blocking agent.

A follow-up study in 28 patients treated with infliximab for severe recalcitrant psoriasis: evidence for efficacy and high incidence of biological autoimmunity

BACKGROUND

Infliximab, an antitumour necrosis factor-alpha chimeric monoclonal antibody, is effective for the treatment of severe psoriasis. While the induction of antinuclear antibodies (ANA) and antidouble-stranded-DNA antibodies (anti-dsDNA-ab) is frequently observed in patients with rheumatoid arthritis and Crohn disease receiving infliximab, the incidence of induced biological and clinical autoimmunity remains unknown in the context of psoriasis.

OBJECTIVES

To investigate biological and clinical signs of autoimmunity in 28 patients receiving infliximab for severe, recalcitrant forms of psoriasis, and the clinical response to treatment.

METHODS

Twenty-eight patients, 15 men and 13 women (median age 39.4 years) with psoriasis refractory to three or more systemic treatments were included. Twenty presented with plaque-type psoriasis [median Psoriasis Area and Severity Index (PASI) score 25.9; range 7.2-48], five with psoriatic erythroderma (median PASI score 54; range 48-72) and three with generalized pustular psoriasis (GPP). Psoriatic arthritis was present in 13 patients (46.4%). Infliximab 5 mg kg(-1) was given at week (W) 0, W2, W6 and every 8 weeks thereafter. Clinical data were assessed at baseline and before each infusion. Detection of ANA and of IgM and IgG anti-dsDNA-ab were performed at baseline and at W22 by immunofluorescence and enzyme-linked immunosorbent assay, respectively.

RESULTS

The mean number of infliximab infusions was 5.5 (range 2-15). Among patients with plaque-type and erythrodermic psoriasis, 17 of 25 (68%) and three of five reached a PASI improvement of 75% or more, respectively, while rapid improvement of clinical and biological signs was observed in all three patients with GPP. The prevalence of positive detection of ANA raised from 12% at baseline to 72% at W22 (P = 0.0001), an increase which was also observed for IgM anti-dsDNA-ab (68% vs. 0%, P < 0.0001), while no significant change was observed for the IgG isotype (16% vs. 0%, P = 0.125). Three patients developed nonerosive polyarthritis, without any other criteria for systemic lupus.

CONCLUSIONS

The incidence of biological autoimmunity is high in patients with refractory psoriasis receiving infliximab. The concomitant onset of polyarthritis in three cases raises the need to investigate the incidence of autoimmune manifestations in psoriatic patients receiving infliximab in further large-scale studies.

Adalimumab clinical efficacy is associated with rheumatoid factor and anti-cyclic citrullinated peptide antibody titer reduction: a one-year prospective study

Studies on autoantibody production in patients treated with tumor necrosis factor-α (TNF-α) inhibitors reported contradictory results. We investigated in a prospective study the efficacy of a treatment with human monoclonal anti-TNF-α antibody (adalimumab) in patients with rheumatoid arthritis (RA) and we evaluated the relationship between treatment efficacy and the incidence and titers of disease-associated and non-organ-specific autoantibodies. Fifty-seven patients with RA not responsive to methotrexate and treated with adalimumab were enrolled. Antinuclear, anti-double-stranded(ds)DNA, anti-extractable nuclear antigens, anti-cardiolipin (aCL), anti-β₂ glycoprotein I (anti-β₂GPI) autoantibodies, rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) autoantibodies were investigated at baseline and after 6 and 12 months of follow-up. Comparable parameters were evaluated in a further 55 patients treated with methotrexate only. Treatment with adalimumab induced a significant decrease in RF and anti-CCP serum levels, and the decrease in antibody titers correlated with the clinical response to the therapy. A significant induction of antinuclear autoantibodies (ANA) and IgG/IgM anti-dsDNA autoantibodies were also found in 28% and 14.6% patients, respectively, whereas aCL and anti-β₂GPI autoantibodies were not detected in significant quantities. No association between ANA, anti-dsDNA, aCL and anti-β₂GPI autoantibodies and clinical manifestations was found. Clinical efficacy of adalimumab is associated with the decrease in RF and anti-CCP serum levels that was detected after 24 weeks and remained stable until the 48th week of treatment. Antinuclear and anti-dsDNA autoantibodies, but not anti-phospholipid autoantibodies, can be induced by adalimumab but to a lower extent than in studies with other anti-TNF blocking agents.

Nucleosomal DNA Fragments in Autoimmune Diseases

The inadequate response of immune cells to circulating apoptotic products, such as nucleosomal DNA fragments, is assumed to be a potent stimulus for the production of autoantibodies during the pathogenesis and progression of systemic lupus erythematosus (SLE). Here, we analyzed the levels of circulating nucleosomes, caspases, and C-reactive protein in sera of 244 individuals with various autoimmune diseases (155 with autoimmune hepatic disorders, 25 with ANCA-associated vasculitis, and 64 with various connective tissue diseases), and 32 healthy controls. Nucleosomes and caspase activities were significantly elevated in sera of patients with hepatic autoimmune diseases, connective tissue diseases, and particularly in ANCA-associated vasculitis when compared with healthy individuals. Nucleosomes showed a correlation with caspases, and caspases with C-reactive protein, but nucleosomes did not correlate with C-reactive protein. Serum levels of the apoptotic products, nucleosomes, and caspases are increased in various autoimmune diseases but may not be solely responsible for antinucleosome antibody production in SLE patients. It remains to be clarified whether qualitative changes in nucleosomes are linked with pathogenesis and disease progression in SLE.

[Systemic lupus erythematosus and nucleosome]

The property of nucleosome in systemic lupus erythematosus (SLE) is reviewed. Nucleosome, complex of histone and DNA, is thought to have a pivotal role in pathogenesis of SLE. It is formed during apoptosis that is increased in peripheral lymphocytes of SLE. The concentration of nucleosome is elevated in SLE, probably related with disease activity. Nucleosome is speculated that the clearance from peripheral blood is decreased and that is modified by viral infection to become more immunogenic. Anti-nucleosome antibody is highly positive in majority of SLE, and is very specific for SLE except scleroderma and mixed connective tissue disease. This antibody is thought as a diagnostic marker and probably an activity marker for SLE. Anti-nucleosome antibody forms immune complex with nucleosome. As histone has strong positive charge, it is demonstrated that this nucleosome/anti-nucleosome complex is bound to negatively charged heparan sulfate of glomerular basement membrane in kidney. Then, complements bind to this antibody to generate lupus glomerulonephritis. Although main site of apoptosis in SLE is considered as lymphocytes, we experienced a case with SLE who had liver dysfunction with elevated soluble Fas ligand (sFasL) and apoptosis in her hepatocytes in the active stage of SLE. We measured serum sFasL, and found the relation of sFasL and liver involvement in active SLE. As major source of nucleosome should be apoptosis of lymphocytes in SLE, hepatocytes could be another candidate of apoptosis in some SLE.

The effect of TNFalpha blockade on the antinuclear antibody profile in patients with chronic arthritis: biological and clinical implications

Since the first proof of efficacy of TNFalpha blockade, both the number of patients treated worldwide and the number of indications for treatment with TNFalpha blockers have grown steadily. Surprisingly, the profound immunomodulation induced by anti-TNFalpha therapy is associated with a relatively low incidence of immune-related complications such as lupus-like syndromes and demyelinating disease. This contrasts sharply with the prominent induction of autoantibodies such as antinuclear antibodies (ANA) and anti-dsDNA antibodies during TNFalpha blockade. Although this phenomenon has been recognized for several years, the clinical and biological implications are not yet fully understood. In this review, recent studies analysing the effect of TNFalpha blockade (infliximab and etanercept) on the ANA profile in autoimmune arthritis will be discussed. Taken together, these reports indicate that the prominent ANA and anti-dsDNA autoantibody response is 1) not a pure class effect of TNFalpha blockers, 2) independent of the disease background, 3) largely restricted to the induction of short-term IgM anti-dsDNA antibodies, and 4) not associated with other serological or clinically relevant signs of lupus. Nevertheless, a careful follow-up of patients treated with TNFalpha blockers remains mandatory, including monitoring for lupus-like characteristics.

Accelerated macrophage apoptosis induces autoantibody formation and organ damage in systemic lupus erythematosus

Increased monocyte/macrophage (Mphi) apoptosis occurs in patients with systemic lupus erythematosus (SLE) and is mediated, at least in part, by an autoreactive CD4(+) T cell subset. Furthermore, autoreactive murine CD4(+) T cells that kill syngeneic Mphi in vitro induce a lupus-like disease in vivo. However, it is unclear whether increased Mphi apoptosis in SLE per se is sufficient to accelerate/promote autoimmunity. We have investigated whether increased Mphi apoptosis in vivo, induced by the administration of clodronate liposomes, can exacerbate the autoimmune phenotype in NZB x SWR (SNF(1)) lupus-prone mice, and induce autoantibody production in haplotype-matched BALB/c x DBA1 (DBF(1)) non-lupus-prone mice. Lupus-prone mice SNF(1) mice that were treated with clodronate liposomes, but not mice treated with vehicle, developed significant increases in autoantibodies to dsDNA, nucleosomes, and the idiotypically related family of nephritic Abs Id(LN)F(1), when compared with untreated SNF(1) mice. Furthermore, clodronate treatment hastened the onset of proteinuria and worsened SNF(1) lupus nephritis. When compared with vehicle-treated controls, clodronate-treated non-lupus-prone DBF(1) mice developed significantly higher levels of anti-nucleosome and Id(LN)F(1) Abs but did not develop lupus nephritis. We propose that Mphi apoptosis contributes to the pathogenesis of autoantibody formation and organ damage through both an increase in the apoptotic load and impairment in the clearance of apoptotic material. This study suggests that mechanisms that induce scavenger cell apoptosis, such as death induced by autoreactive cytotoxic T cells observed in SLE, could play a pathogenic role and contribute to the severity of the disease.

Musculoskeletal manifestations and autoimmune diseases related to new biologic agents

PURPOSE OF REVIEW

The anti-tumor necrosis factor agents are now widely used in the management of patients with rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis and juvenile inflammatory arthritis. One of the most common observations made during their use is the development of autoantibodies. The purpose of this paper is to review this phenomenon and its clinical implications.

RECENT FINDINGS

While the development of different autoantibodies is a common encounter, rare cases of lupus-like syndromes have been reported. On the other hand, a variety of immune-mediated clinical manifestations have been described, including vasculitis and demyelinating syndromes. Rare cases of cytopenia and non-specific lung injuries have also been reported.

SUMMARY

While these clinical complications are rare and isolated events, clinicians must be aware of their occurrence. The experience with the anti-tumor necrosis factor agents is rather short and new, unusual immune-mediated complications may still appear. Clinicians should be prepared to recognize them.

Intracellular mammalian DNA stimulates myeloid dendritic cells to produce type I interferons predominantly through a toll-like receptor 9–independent pathway

OBJECTIVE

Exogenous nucleic acids, including bacterial unmethylated DNA and viral single-stranded RNA, are potent activators of innate immunity through interaction with the Toll-like receptors (TLRs). In contrast, mammalian DNA has been generally thought to have a limited activation effect, or even a suppressive effect, on innate immunity. Since DNA is a major component of dying cells and recent studies indicate that mammalian nucleic acids may be stimulatory under certain conditions, we undertook this study to examine the effect of intracellular mammalian DNA on myeloid dendritic cell (DC) activation.

METHODS

Mammalian DNA was introduced into murine bone marrow-derived DCs (BMDCs) by transfection. BMDC activation was determined by flow cytometry (CD40, CD86). Production of tumor necrosis factor alpha and interleukin-6 was measured by enzyme-linked immunosorbent assay, and production of type I interferons (IFNs) by bioassay. Parallel studies were conducted using BMDCs from mice deficient in myeloid differentiation 88 (MyD88), TLR-9, and IFNalpha/beta receptor.

RESULTS

Intracellular mammalian DNA activated immature BMDCs, as determined by the up-regulation of CD40 and CD86 as well as by the production of significant quantities of type I IFN. The interferogenic response was shown to be relatively independent of TLR-9, and the TLR adaptor MyD88. The IFN response to intracellular DNA was reduced in BMDCs lacking IFNalpha/beta receptor but was intact in embryonic fibroblasts lacking protein kinase R.

CONCLUSION

These results indicate that intracellular DNA stimulates BMDC maturation and IFN production predominantly through a TLR-independent pathway, and support a model whereby inefficient clearance and/or degradation of endogenous DNA may stimulate innate immune responses similar to the TLR-independent response to exogenous (i.e., viral) double-stranded RNA.

The binding of sera of patients with SLE to bacterial and mammalian DNA

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease characterized by antibodies to DNA (anti-DNA). Although these antibodies have features of antigen drive, the source of this DNA is not defined. To assess the potential role of foreign and self-DNA as driving antigens, the specificity of SLE sera for bacterial and mammalian DNA was evaluated. Micrococcus lysodeikticus (MC) and calf thymus (CT) DNA were tested as antigens, with absorption on CT DNA columns used to identify antibodies to antigenic sites on the two DNA. Among 9 sets of longitudinal sera tested, all showed binding to both DNA, and none showed exclusive or predominant binding to CT DNA. With absorbed sera, antibodies could be distinguished in terms of cross-reactive or selective binding to the DNAs. These findings suggest that anti-DNA antibodies vary in specificity and are consistent with a role of both foreign and self-DNA in anti-DNA induction.

Systemic lupus erythematosus induced by anti-tumour necrosis factor alpha therapy: a French national survey

The development of drug-induced lupus remains a matter of concern in patients treated with anti-tumour necrosis factor (TNF) alpha. The incidence of such adverse effects is unknown. We undertook a retrospective national study to analyse such patients.

Between June and October 2003, 866 rheumatology and internal medicine practitioners from all French hospital centres prescribing anti-TNF in rheumatic diseases registered on the website of the 'Club Rhumatismes et Inflammation' were contacted by email to obtain the files of patients with TNF-induced systemic lupus erythematosus. Twenty-two cases were collected, revealing two aspects of these manifestations. Ten patients (six patients receiving infliximab, four patients receiving etanercept) only had anti-DNA antibodies and skin manifestations one could classify as 'limited skin lupus' or 'toxidermia' in a context of autoimmunity, whereas 12 patients (nine patients receiving infliximab, three patients receiving etanercept) had more complete drug-induced lupus with systemic manifestations and at least four American Congress of Rheumatology criteria. One patient had central nervous system manifestations. No patients had lupus nephritis. The signs of lupus occurred within a mean of 9 months (range 3–16 months) in patients treated with infliximab and within a mean of 4 months (range 2–5 months) in patients treated with etanercept. In all cases after diagnosis was determined, anti-TNF was stopped and specific treatment introduced in eight patients: two patients received intravenous methylprednisolone, four patients received oral steroids (15–35 mg/day), and two patients received topical steroids. Lupus manifestations abated within a few weeks (median 8 weeks, standard deviation 3–16) in all patients except one with longer-lasting evolution (6 months). At that time, cautious estimations (unpublished data from Schering Plough Inc. and Wyeth Inc.) indicated that about 7700 patients had been exposed to infliximab and 3000 to etanercept for inflammatory arthritides in France. It thus appears that no drug was more implicated than the other in lupus syndromes, whose incidence was 15/7700 = 0.19% with infliximab and 7/3800 = 0.18% with etanercept.

Clinicians should be aware that lupus syndromes with systemic manifestations may occur in patients under anti-TNF alpha treatment.

Evidence that anti-tumor necrosis factor therapy with both etanercept and infliximab induces apoptosis in macrophages, but not lymphocytes, in rheumatoid arthritis joints: extended report

OBJECTIVE

Treatment of rheumatoid arthritis (RA) with tumor necrosis factor (TNF) antagonists is highly effective, but their mechanisms of action are not completely clear. Since anti-TNF therapy induces a decrease in synovial cellularity, this study focused on the modulation of RA synovial apoptosis following treatment with either soluble TNF receptor (etanercept) or TNF chimeric monoclonal antibody (infliximab).

METHODS

Apoptosis (TUNEL and active caspase 3 staining) and cell surface markers were evaluated by immunohistochemistry in synovial biopsy samples obtained before and after 8 weeks of treatment with etanercept (12 patients) or infliximab (9 patients). We also determined by flow cytometry the in vitro effect of etanercept and infliximab on apoptosis of RA mononuclear cells derived from the synovial fluid (SF) and peripheral blood (PB).

RESULTS

Eight weeks of treatment with etanercept and with infliximab significantly increased synovial apoptosis. This change was accompanied by a significant decrease in the synovial monocyte/macrophage population. The decrease in lymphocyte numbers did not reach statistical significance. In vitro, 24 hours of incubation with either etanercept or infliximab induced apoptosis of the SF monocyte/macrophage population. PB monocyte/macrophages were less susceptible to anti-TNF-mediated apoptosis. No changes in the rate of apoptosis were observed in the lymphocyte population derived from either SF or PB.

CONCLUSION

In RA patients, both etanercept and infliximab are able to induce cell type-specific apoptosis in the monocyte/macrophage population. This suggests a potential pathway that would account for the diminished synovial inflammation and the decreased numbers of synovial macrophages evident after TNF blockade.