Immunoglobulin light chain allelic inclusion in systemic lupus erythematosus.

The principles of allelic exclusion state that each B cell expresses a single light and heavy chain pair. Here, we show that B cells with both kappa and lambda light chains (Igκ and Igλ) are enriched in some patients with the systemic autoimmune disease systemic lupus erythematosus (SLE), but not in the systemic autoimmune disease control granulomatosis with polyangiitis. Detection of dual Igκ and Igλ expression by flow cytometry could not be abolished by acid washing or by DNAse treatment to remove any bound polyclonal antibody or complexes, and was retained after two days in culture. Both surface and intracytoplasmic dual light chain expression was evident by flow cytometry and confocal microscopy. We observed reduced frequency of rearrangements of the kappa-deleting element (KDE) in SLE and an inverse correlation between the frequency of KDE rearrangement and the frequency of dual light chain expressing B cells. We propose that dual expression of Igκ and Igλ by a single B cell may occur in some patients with SLE when this may be a consequence of reduced activity of the KDE.

Pregnancy outcome in patients with systemic vasculitis: a single-centre matched case-control study.

OBJECTIVE: To study the outcome of pregnancy in patients with systemic vasculitis (SV) compared with age-, BMI- and ethnicity-matched healthy pregnant controls. METHODS: Fifty-one pregnancies in 29 SV patients were retrospectively studied. There were nine patients with granulomatosis with polyangiitis (GPA), three with eosinophilic GPA, seven with Takayasu's arteritis, two with ANCA-positive vasculitis with renal involvement, two with Behçet's disease, three with urticarial vasculitis, one with primary cerebral vasculitis, one with relapsing polychondritis and one with IgA vasculitis. BVAS and the vasculitis damage index were evaluated retrospectively. Sixty-two healthy women with 156 pregnancies matched in a 2:1 ratio for age, BMI and ethnicity formed the control group. RESULTS: Median gestational age at delivery was lower in the SV group: 36 weeks and 2 days (34-42) vs controls 40 (37-42) weeks (P < 0.03). Median birth weight in the SV group was 3.0 kg (2.0-5.2), whereas that of the controls was 3.5 (2.28-4.32) kg (P = 0.004). The median customized birth weight centile was 38.6 in the SV group and 37.2 in the control group. In the SV group, 9 patients had 13 miscarriages, 3 had pre-eclampsia, and 2 had an intrauterine death. In the control group, 20 patients had 27 miscarriages, 1 had pre-eclamptic toxaemia, and 1 had an antepartum haemorrhage. Eight patients with SV flared during pregnancy and 11 flared after delivery. CONCLUSION: Patients with SV had a lower median gestational age, but customized birth weights were similar to those of healthy women. Women with SV may flare during pregnancy and the post-partum period and may experience significant pregnancy morbidity.

Diagnosis and classification of granulomatosis with polyangiitis (aka Wegener's granulomatosis).

Granulomatosis with polyangiitis (GPA, formerly known as Wegener's Granulomatosis) is an autoimmune small vessel vasculitis which is highly associated with anti-neutrophil cytoplasmic antibodies (ANCA). The hallmarks of this condition are systemic necrotising vasculitis, necrotising granulomatous inflammation, and necrotising glomerulonephritis. The aetiology of granulomatosis with polyangiitis is linked to environmental and infectious triggers inciting onset of disease in genetically predisposed individuals. Anti-neutrophil cytoplasmic antibodies are pathogenic and play an important role in the pathogenesis of this disease, although ANCA positivity is not essential for a clinical diagnosis of granulomatosis with polyangiitis. Granulomatosis with polyangiitis is diagnosed based on clinical manifestations of systemic vasculitis and histological evidence of necrotising vasculitis or granulomatous inflammation. This small vessel vasculitis may present as limited disease of the ears, nose and upper airways or mild, moderate or severe systemic disease. Immunosuppression and adjuvant therapies have contributed to the improved prognosis of granulomatosis with polyangiitis over the past decades. Treatment strategies are tailored to the severity of the disease. They are based on published evidence of the efficacy and safety of the immunosuppressive drugs indicated to manage active vasculitis and maintain clinical remission. This review will summarise the history, aetiology, pathogenesis, classification, diagnosis and management of granulomatosis with polyangiitis.

Circulating T follicular helper cell and regulatory T cell frequencies are influenced by B cell depletion in patients with granulomatosis with polyangiitis.

OBJECTIVE: Granulomatosis with polyangiitis (GPA) is a rare and sometimes fatal systemic autoimmune disease. ANCAs specific for PR3 are associated with GPA. Remission in GPA can be achieved through B cell depletion (BCD) therapy. Our aim was to understand whether the frequencies of T cell subsets are influenced by BCD. METHODS: The frequencies of circulating T follicular helper cells (cTFHs) and regulatory T cells (Tregs) from 36 GPA patients including 11 rituximab-treated patients and 10 healthy controls were studied by flow cytometry. The functional capacity of Tregs was assessed by in vitro co-culture assays. RESULTS: We observed an increased frequency of cTFHs and a reduced frequency of antigen-experienced Tregs in peripheral blood from GPA patients on conventional therapies but not in those treated with rituximab compared with healthy controls. Furthermore, the ratio of cTFHs to Tregs was significantly higher in GPA patients on conventional therapies than in GPA patients treated with rituximab who were clinically improved or controls. Whereas Tregs were numerically reduced in GPA patients on conventional therapy, the suppressive capacity of Tregs on a per cell basis was not significantly altered in these individuals. CONCLUSION: Our study illustrated increased cTFHs with decreased antigen-experienced Tregs in GPA patients on conventional therapies, but in B cell-depleted patients the levels of cTFHs and Tregs were similar to healthy controls. The negative correlation between cTFHs and Tregs implies the balance between T cell subsets and its B cell dependence impact on disease activity in GPA.

Novel therapeutic agents in clinical development for systemic lupus erythematosus.

Conventional immunosuppressive therapies have radically transformed patient survival in systemic lupus erythematosus (SLE), but their use is associated with considerable toxicity and a substantial proportion of patients remain refractory to treatment. A more comprehensive understanding of the complexity of SLE immunopathogenesis has evolved over the past decade and has led to the testing of several biologic agents in clinical trials. There is a clear need for new therapeutic agents that overcome these issues, and biologic agents offer exciting prospects as future SLE therapies.An array of promising new therapies are currently emerging or are under development including B-cell depletion therapies, agents targeting B-cell survival factors, blockade of T-cell co-stimulation and anti-cytokine therapies, such as monoclonal antibodies against interleukin-6 and interferon-α.

B-cell depletion therapy and pregnancy outcome in severe, refractory systemic autoimmune diseases.

OBJECTIVE: To study the pregnancy outcome following Rituximab treatment before conception in patients with refractory autoimmune rheumatic diseases. METHODOLOGY: Five women with systemic lupus erythematosus (SLE) and 1 woman with ANCA positive vasculitis fulfilling the respective ACR classification criteria were studied retrospectively when they became pregnant following rituximab treatment for refractory disease. Rituximab was given as a 1 g infusion together with 500 mg Methylprednisolone, on day 1 and day 15 after written informed consent. RESULTS: The median age was 34 (range 32-39) years and median disease duration was 10 (range 5-16) years. All the patients achieved complete B-cell depletion < 1 cell/µL at 1 month and <5 cells/µL at 6 months with prolonged B-cell depletion. Four women had successful pregnancies with median gestational age of 38 (range 31-40) weeks; median weight of the new born was 3.25 (range1.17-3.3) kg with no documented adverse neonatal events. One patient with lupus nephritis (LN) had a premature delivery and increasing proteinuria in the third trimester. One other patient with LN had a premature delivery and the new born had oesophageal atresia. CONCLUSION: We report a child with oesophageal atresia born to a mother with lupus nephritis who had received Rituximab 12 months prior to conception, while four other pregnancies in women with SLE resulted in morphologically normal children. We also describe the first report, to our knowledge, of a successful pregnancy outcome in a woman with granulomatosis with polyangiitis treated with rituximab.

Biological drugs in ANCA-associated vasculitis.

The anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitides granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA) and microscopic polyangiitis (MPA) constitute a wide spectrum of clinical manifestations of systemic vasculitis which may range from limited disease to organ or life-threatening disease. The introduction of biologics for the management of severe ANCA-associated vasculitis and severe, relapsing disease refractory to conventional immunosuppressants, has significantly improved the clinical prognosis of these autoimmune disorders. Rituximab, an anti-CD20 monoclonal antibody is licenced for remission induction in severe GPA and MPA and the management of severe relapsing, refractory GPA and MPA. Belimumab, an anti-B lymphocyte stimulatory monoclonal antibody is in clinical trials for the management of the ANCA-associated vasculitis GPA. Mepolizumab and Omalizumab are biologics which have been reported to be efficacious in refractory asthma associated with EGPA. The role of anti-TNF therapy and T cell targeting drugs in ANCA-associated vasculitis is less clear due to limited study data. This review will summarise the clinical trials and clinical practice use of biologic treatment strategies for the management of ANCA-associated vasculitis.

Immunoglobulin kappa variable region gene selection during early human B cell development in health and systemic lupus erythematosus.

The unique specificity of the B cell receptor is generated by an ordered sequence of gene rearrangement events. Once IGH genes have rearranged, rearrangement at the IGK locus is initiated followed by the IGL locus if functional IGK rearrangement is not achieved. Receptor specificity can subsequently be altered by secondary light chain editing based on the features of the heavy and light chain combination. The final profile of expressed genes is not random and biases in this profile are associated with several autoimmune diseases. However, how and when biases are created is not known. To increase our understanding of the processes of selection and editing of IGK rearrangements, we compared four groups of rearrangements of IGK acquired by next generation sequencing. First, expressed rearrangements of IGK from cDNA of IGK expressing B cells. Second, productive rearrangements of IGK from DNA of the same kappa expressing B cells. Third, non-productive rearrangements of IGK from DNA of IGK and IGL expressing B cells, and fourth productively rearranged IGK from DNA of IGL expressing B cells. The latter group would have been rejected during B cell development in favour of rearrangement at the IGL locus and are therefore selected against. We saw evidence that rearranged IGK segments can be selected at a checkpoint where the decision to rearrange the IGL locus is made. In addition, our data suggest that mechanisms regulating the expression or not of IGK rearrangements may also contribute to repertoire development and also that this latter component of the selection process is defective in SLE.

Update on belimumab for the management of systemic lupus erythematosus.

INTRODUCTION: Belimumab is a fully humanised mAb against B lymphocyte stimulator (B-LyS). It is the first biological drug to be licensed and approved by the US FDA and the European Medicines Evaluation Agency for use in combination with standard immunosuppressants in autoantibody-positive systemic lupus erythematosus (SLE). The clinical effectiveness and impact of this drug on lupus morbidity and mortality is evaluated in this review. AREAS COVERED: An overview of the efficacy and safety of belimumab based on 7-year longitudinal continuation study data from SLE patients enrolled in the Phase II double-blind, randomised, placebo-controlled, 52-week study of belimumab 1, 4 and 10 mg/kg doses and an overview of the open-label 24-week extension of belimumab plus standard immunosuppressant therapy. A review of the current belimumab clinical trials, the experience of belimumab in real-world settings and a description of the impact that belimumab has had on the healthcare quality of life of SLE patients. EXPERT OPINION: The emerging clinical data have shed light on the areas in which belimumab is of greatest benefit and areas for further evaluation in clinical trials. It is anticipated that regular updates from ongoing trials of belimumab in SLE, practising physicians, data from the continuation arms of clinical trials and data from international biologics registries will have an influence on the role of belimumab in the management of SLE.

Which dose of steroids and which cytotoxics for severe lupus?

There have been a number of major advances in the treatment of systemic lupus erythematosus and we are now in the era of biologic therapies for this multisystem autoimmune disorder. There has been a greater awareness of the toxicities of the traditional therapies including the recognition that the doses of corticosteroids used in the past have been excessive, resulting in unacceptable toxicities. Other advances have included the development of lower cumulative doses of cyclophosphamide and the widespread acceptance of mycophenolate mofetil for the treatment of lupus nephritis. This review addresses the current management of severe lupus with corticosteroids and cytotoxic agents.

Belimumab for the management of systemic lupus erythematosus.

INTRODUCTION: In 2011, Belimumab , a fully humanized monoclonal antibody against B lymphocyte stimulator, became the first biological agent to be licensed by the United States Food and Drug Administration (FDA) and the European Medicines Evaluation Agency (EMEA) for the use in auto-antibody positive adult Systemic Lupus Erythematosus (SLE). AREAS COVERED: An overview of the clinical trial data, review of the medical and scientific literature following a MEDLINE search forms the basis of this expert opinion on biological therapy review. The Belimumab International SLE Study Phase III randomized placebo-controlled trials, BLISS-52 and BLISS-76, met the primary endpoint based on the SLE responder index (SRI) at week 52. The trials reported that belimumab 10 mg/kg infusions with standard therapy significantly reduced SLE disease activity compared with placebo with standard therapy. EXPERT OPINION: The clinical efficacy, safety and tolerability of belimumab indicates a potential role for this drug in achieving disease control, reducing severity of recurrent flares, reducing morbidity and in the long-term achieving a positive long-term impact on quality of life. Belimumab is now being introduced in clinical practice and over the next 5 years data on its use outside the clinical trials will determine its place in SLE management.