Abatacept reduces levels of switched memory B cells, autoantibodies, and immunoglobulins in patients with rheumatoid arthritis

Immune-related adverse events of immune checkpoint inhibitors: a review

Since the first Immune Checkpoint Inhibitor was developed, tumor immunotherapy has entered a new era, and the response rate and survival rate of many cancers have also been improved. Despite the success of immune checkpoint inhibitors, resistance limits the number of patients who can achieve a lasting response, and immune-related adverse events complicate treatment. The mechanism of immune-related adverse events (irAEs) is unclear. We summarize and discuss the mechanisms of action of immune checkpoint inhibitors, the different types of immune-related adverse events and their possible mechanisms, and describe possible strategies and targets for prevention and therapeutic interventions to mitigate them.

Combining nanotechnology with monoclonal antibody drugs for rheumatoid arthritis treatments

Rheumatoid arthritis (RA) is a systemic immune disease characterized by synovial inflammation. Patients with RA commonly experience significant damage to their hand and foot joints, which can lead to joint deformities and even disability. Traditional treatments have several clinical drawbacks, including unclear pharmacological mechanisms and serious side effects. However, the emergence of antibody drugs offers a promising approach to overcome these limitations by specifically targeting interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and other cytokines that are closely related to the onset of RA. This approach reduces the incidence of adverse effects and contributes to significant therapeutic outcomes. Furthermore, combining these antibody drugs with drug delivery nanosystems (DDSs) can improve their tissue accumulation and bioavailability.Herein, we provide a summary of the pathogenesis of RA, the available antibody drugs and DDSs that improve the efficacy of these drugs. However, several challenges need to be addressed in their clinical applications, including patient compliance, stability, immunogenicity, immunosupression, target and synergistic effects. We propose strategies to overcome these limitations. In summary, we are optimistic about the prospects of treating RA with antibody drugs, given their specific targeting mechanisms and the potential benefits of combining them with DDSs.

Abatacept ameliorates both glandular and extraglandular involvements in patients with Sjögren's syndrome associated with rheumatoid arthritis: Findings from an open-label, multicentre, 1-year, prospective study: The ROSE (Rheumatoid Arthritis with Orencia Trial Toward Sjögren's Syndrome Endocrinopathy) and ROSE II trials

OBJECTIVE

To clarify the efficacy and safety of intravenous abatacept for glandular and extraglandular involvements in Sjögren's syndrome (SS) associated with rheumatoid arthritis (RA).

MATERIALS AND METHODS

We performed an open-label, prospective, 1-year, observational multicenter study (ROSE and ROSE II trials). The primary endpoint was the remission rate as measured by SDAI at 52 weeks. The secondary endpoints included the changes in the Saxon's test, Schirmer's test, ESSDAI and ESSPRI. Adverse events and adherence rates were also analyzed.

RESULTS

68 patients (36 in ROSE and 32 in ROSE II, all women) were enrolled. SDAI decreased significantly from 23.6 ± 13.2 at baseline to 9.9 ± 9.5 at 52 weeks. Patients with SDAI remission increased from 0 (0 weeks) to 19 patients (27.9%) at 52 weeks. Saliva volume increased significantly at 24 weeks. Tear volume increased significantly at 52 weeks. Both ESSDAI and ESSPRI were significantly decreased at 12 weeks, and these responses were maintained up to 52 weeks. The rate of adherence to abatacept over the 52-week period was 83.8%. Twenty-two adverse events occurred in 15 patients.

CONCLUSION

Abatacept ameliorated both glandular and extraglandular involvements, as well as the systemic disease activities and patient-reported outcomes based on composite measures, in SS associated with RA.

Persistence of SARS-CoV-2 neutralizing antibodies and anti-Omicron IgG induced by BNT162b2 mRNA vaccine in patients with autoimmune inflammatory rheumatic disease: an explanatory study in Japan

Background

Autoimmune inflammatory rheumatic disease (AIRD) patients are at high risk of the coronavirus disease 2019 (COVID-19), but the medium-term effects of immunosuppressants on vaccine efficacy are unknown. We investigated the duration of humoral responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) wild-type and Omicron variant in AIRD patients administered with two doses of the BNT162b2 (Pfizer-BioNTech) vaccine.

Methods

Serum-neutralizing antibody (NAb) and anti-receptor-binding domain (RBD)/spike antibody levels were measured. Short- and medium-term effects of immunosuppressants were analyzed pre-vaccination (Term 1) and 14-42 days (Term 2) and 100-200 days (Term 3) after the second vaccination.

Findings

From Feb 1, 2021, to Feb 28, 2022, 439 AIRD patients and 146 healthy controls were investigated. The seropositivity rate and log₁₀-NAb titers were significantly lower in AIRD patients than in controls at Terms 2 and 3. In rheumatoid arthritis patients, tumor necrosis factor-α inhibitors (TNFis) at Term 3, and older age, glucocorticoids, and abatacept at Terms 2 and 3 were risk factors for reduced responses. Anti-Omicron RBD/spike IgG levels strongly correlated with NAb titers.

Interpretation

Glucocorticoids, TNFis, and abatacept treatments negatively affect the longevity of humoral responses to SARS-CoV-2, including Omicron, after two vaccine doses. These findings may inform the timing of additional vaccination for AIRD patients.

Funding

Cloud Funding of Peace Winds Japan; Center of Innovation Program from the Ministry of Education, Culture, Sports, Science and Technology of Japan; Japan Society for the Promotion of Science KAKENHI; Japan Agency for Medical Research and Development; Kansai Economic Federation; Mitsubishi Zaidan; and Research Grant from Japan Agency for Medical Research and Development-Core Research for Evolutional Science and Technology.

CTLA-4-Ig internalizes CD80 in fibroblast-like synoviocytes from chronic inflammatory arthritis mouse model

CD80 interact with CD28 and CTLA-4 on antigen-presenting cells, and function in the co-stimulatory signaling that regulates T cell activity. CTLA-4-Ig is used to treat RA by blocking co-stimulatory signaling. Chronic inflammatory arthritis was induced in D1BC mice using low-dose arthritogenic antigens and treated with CTLA-4-Ig. We performed histopathology of the joints and lymph nodes, serological examination for rheumatoid factors, and flow cytometric analysis of isolated synovial cells, including CD45^- FLSs and CD45⁺ synovial macrophages. CTLA-4-Ig treatment ameliorated the chronic inflammatory polyarthritis. There was a decrease in the number of infiltrating lymphoid cells in the joints as well as in the levels of RF-IgG associated with a decrease in the number of B cells in the lymph nodes; more than 15% of CD45^- FLSs expressed CD80, and a small number of them expressed PD-L1, indicating the presence of PD-L1/CD80 cis-heterodimers in these cells. CTLA-4-Ig internalized CD80, but not PD-L1, in isolated synovial cells. Gene ontology analysis revealed that CTLA-4-Ig internalization did not significantly alter the expression of inflammation-related genes. The therapeutic effect of CTLA-4-Ig appears to extend beyond the lymph nodes into the inflamed synovial compartment through the synergistic inactivation of T cells by the CD80 and PD-L1 axes.

Mono/polyclonal free light chains as challenging biomarkers for immunological abnormalities

Free light chain (FLC) kappa (k) and lambda (λ) consist of low molecular weight proteins produced in excess during immunoglobulin synthesis and secreted into the circulation. In patients with normal renal function, over 99% of FLCs are filtered and reabsorbed. Thus, the presence of FLCs in the serum is directly related to plasma cell activity and the balance between production and renal clearance. FLCs are bioactive molecules that may exist as monoclonal (m) and polyclonal (p) FLCs. These have been detected in several body fluids and may be key indicators of ongoing damage and/or illness. International guidelines now recommend mFLC for screening, diagnosis and monitoring multiple myeloma and other plasma cell dyscrasias. In current clinical practice, FLCs in urine indicate cast nephropathy and other renal injury, whereas their presence in cerebrospinal fluid is important for identifying central nervous system inflammatory diseases such as multiple sclerosis. Increased pFLCs have also been detected in various conditions characterized by B cell activation, i.e., chronic inflammation, autoimmune disease and HCV infection. Monitoring the coronavirus (COVID-19) pandemic by analysis of salivary FLCs presents a significant opportunity in clinical immunology worthy of scientific pursuit.

Kinetics of the B- and T-Cell Immune Responses After 6 Months From SARS-CoV-2 mRNA Vaccination in Patients With Rheumatoid Arthritis

Objective

To assess the kinetics of the humoral and cell-mediated responses after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in rheumatoid arthritis (RA) patients treated with different immunosuppressive therapies.

Methods

Following vaccine completed schedule, health care workers (HCWs, n = 49) and RA patients (n = 35) were enrolled at 5 weeks (T1) and 6 months (T6) after the first dose of BNT162b2-mRNA vaccination. Serological response was assessed by quantifying anti-receptor-binding domain (RBD)-specific immunoglobulin G (IgG) and SARS-CoV-2 neutralizing antibodies, while cell-mediated response was assessed by a whole-blood test quantifying the interferon (IFN)-γ response to spike peptides. B-cell phenotype and IFN-γ-specific T-cell responses were evaluated by flow cytometry.

Results

After 6 months, anti-RBD antibodies were still detectable in 91.4% of RA patients, although we observed a significant reduction of the titer in patients under Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4)-Ig [median: 16.4 binding antibody units (BAU)/ml, interquartile range (IQR): 11.3–44.3, p < 0.0001] or tumor necrosis factor (TNF)-α inhibitors (median: 26.5 BAU/ml, IQR: 14.9–108.8, p = 0.0034) compared to controls (median: 152.7 BAU/ml, IQR: 89.3–260.3). All peripheral memory B-cell (MBC) subpopulations, in particular, the switched IgG+ MBCs (CD19+CD27+IgD-IgM-IgG+), were significantly reduced in RA subjects under CTLA-4-Ig compared to those in HCWs (p = 0.0012). In RA patients, a significantly reduced anti-RBD IgG titer was observed at T6 vs. T1, mainly in those treated with CTLA-4-Ig (p = 0.002), interleukin (IL)-6 inhibitors (p = 0.015), and disease-modifying antirheumatic drugs (DMARDs) ± corticosteroids (CCSs) (p = 0.015). In contrast, a weak nonsignificant reduction of the T-cell response was reported at T6 vs. T1. T-cell response was found in 65.7% of the RA patients at T6, with lower significant magnitude in patients under CTLA-4-Ig compared to HCWs (p < 0.0001). The SARS-CoV-2 IFN-γ-S-specific T-cell response was mainly detected in the CD4+ T-cell compartment.

Conclusions

In this study, in RA patients after 6 months from COVID-19 vaccination, we show the kinetics, waning, and impairment of the humoral and, to a less extent, of the T-cell response. Similarly, a reduction of the specific response was also observed in the controls. Therefore, based on these results, a booster dose of the vaccine is crucial to increase the specific immune response regardless of the immunosuppressive therapy.

Distinct impact of DMARD combination and monotherapy in immunogenicity of an inactivated SARS-CoV-2 vaccine in rheumatoid arthritis

OBJECTIVES

To evaluate the distinct impact of disease modifying antirheumatic drugs (DMARD) combination and monotherapy in immune response to an inactivated SARS-CoV-2 vaccine in patients with rheumatoid arthritis (RA).

METHODS

This phase 4 prospective study analysed seroconversion (SC) of anti-SARS-CoV-2 immunoglobulin G (IgG) and neutralising antibodies (NAb) induced by the inactivated vaccine (CoronaVac) in patients with RA in comparison to controls (CG). Disease activity and treatment were also assessed. Only participants with baseline negative IgG/NAb were included.

RESULTS

Patients with RA (N=260) and CG (N=104) had comparable median ages (59 years (50-65 years) vs 58 years (49.8-64 years), p=0.483). Patients with RA had moderate but lower SC (61.8% vs 94.2%, p<0.001) and NAb positivity (45% vs 78.6%, p<0.001) in comparison to CG after full vaccination. Baseline disease activity did not influence immunogenicity (p>0.05). After multivariate analyses, factors independently related to reduced SC were: older age (OR=0.79 (0.70-0.89) for each 5-year interval, p<0.001), methotrexate (OR=0.54 (0.29-0.98), p=0.044), abatacept (OR=0.37 (0.19-0.73), p=0.004) and number of DMARD (OR=0.55 (0.33-0.90), p=0.018). Regarding NAb, age (OR=0.87 (0.78-0.96) for each 5-year interval, p=0.007) and prednisone >7.5 mg/day (OR=0.38 (0.19-0.74), p=0.004) were negatively related to the presence of NAb. Further comparison of SC/NAb positivity among RA treatment subgroups and CG revealed that methotrexate/tofacitinib/abatacept/tocilizumab use, in monotherapy or in combination, resulted in lower responses (p<0.05), while tumour necrosis factor inhibitor and other conventional synthetic DMARD interfered solely when combined with other therapies.

CONCLUSIONS

Patients with RA under DMARD have a moderate immunogenicity to CoronaVac. We identified that nearly all DMARD combinations have a deleterious effect in immunogenicity, whereas a more restricted number of drugs (methotrexate/tofacitinib/abatacept/tocilizumab) also hampered this response as monotherapy. These findings reinforce the need of a broader approach, not limited to specific drugs, to improve vaccine response for this population.

TRIAL REGISTRATION DETAILS

NCT04754698.

Toward Overcoming Treatment Failure in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by inflammation and bone erosion. The exact mechanism of RA is still unknown, but various immune cytokines, signaling pathways and effector cells are involved. Disease-modifying antirheumatic drugs (DMARDs) are commonly used in RA treatment and classified into different categories. Nevertheless, RA treatment is based on a "trial-and-error" approach, and a substantial proportion of patients show failed therapy for each DMARD. Over the past decades, great efforts have been made to overcome treatment failure, including identification of biomarkers, exploration of the reasons for loss of efficacy, development of sequential or combinational DMARDs strategies and approval of new DMARDs. Here, we summarize these efforts, which would provide valuable insights for accurate RA clinical medication. While gratifying, researchers realize that these efforts are still far from enough to recommend specific DMARDs for individual patients. Precision medicine is an emerging medical model that proposes a highly individualized and tailored approach for disease management. In this review, we also discuss the potential of precision medicine for overcoming RA treatment failure, with the introduction of various cutting-edge technologies and big data.

Abatacept Promotes Regulatory B Cell Functions, Enhancing Their Ability to Reduce the Th1 Response in Rheumatoid Arthritis Patients through the Production of IL-10 and TGF-β

Abatacept mimics natural CD152 and competes with CD28 for binding to CD80/CD86 on APC, such as B cells, thereby preventing T cell activation. However, its potential impact on B cells has not been identified. The aim of this study was to assess whether abatacept can potentiate the immunoregulatory properties of B cells in vitro and in patients with rheumatoid arthritis (RA). T and B cells from healthy controls were purified. The suppressor properties of B cells in the presence of abatacept or control IgG1 were evaluated based on the ability of these cells to inhibit the polyclonal expansion (anti-CD3/CD28 stimulation) of T cells or their differentiation into Th1 or Th17 cells. Similar analyses were also performed with cells from RA patients before and 3 mo after abatacept initiation. Abatacept significantly potentiated regulatory B cell regulatory functions by enhancing their ability to produce IL-10 and TGF-β, resulting in the increased generation of regulatory T cells and limited T cell proliferation and differentiation into Th1 and Th17 cells. Interestingly, B cells isolated from patients that received a 3-mo treatment with abatacept had an increased ability to reduce T cell functions, confirming the above observations. Abatacept binding to CD80/CD86 induces and promotes regulatory B cell functions by enhancing the ability of these cells to produce IL-10 and TGF-β in vitro and in RA patients.

Blood PD-1+TFh and CTLA-4+CD4+ T cells predict remission after CTLA-4Ig treatment in early rheumatoid arthritis

OBJECTIVE

Treatment with CTLA-4Ig blocks T cell activation and is clinically effective in rheumatoid arthritis (RA). However, it is unknown if specific CD4+ T cell subsets in blood at baseline predict remission after CTLA-4Ig, or other biological treatments with different modes of action, and how treatment affects CD4+ T cells in patients with untreated early RA (eRA).

METHODS

This study included 60 patients with untreated eRA from a larger randomised trial. They were treated with methotrexate combined with CTLA-4Ig (abatacept, n = 17), anti-IL6 receptor (tocilizumab, n = 21) or anti-TNF (certolizumab-pegol, n = 22). Disease activity was assessed by clinical disease activity index (CDAI), DAS28, swollen joint counts, tender joint counts, CRP and ESR. The primary outcome was CDAI remission (CDAI ≤ 2.8) at week 24. Proportions of 12 CD4+ T cell subsets were measured by flow cytometry at baseline and after 4, 12 and 24 weeks of treatment.

RESULTS

In patients treated with CTLA-4Ig, the proportions of PD-1+TFh and CTLA-4+ conventional CD4+ T cells at baseline predicted CDAI remission at week 24. CD4+ T cell subset proportions could not predict remission after treatment with anti-IL6R or anti-TNF. The percentage of regulatory T cells (Tregs) expressing CTLA-4 decreased in all treatment arms by 24 weeks, but only CTLA-4Ig treatment significantly reduced the proportions of Tregs and PD-1+T follicular helper (TFh) cells.

CONCLUSION

These findings indicate that circulating proportions PD-1+TFh and CTLA-4+ conventional CD4+ T cells at baseline may serve as predictive biomarkers for remission in early RA after CTLA-4Ig treatment.

Humoral Immunity to Varicella Zoster Virus in Patients with Systemic Lupus Erythematosus and Rheumatoid Arthritis Compared to Healthy Controls

Background: The prevalence of herpes zoster (HZ) is high in patients with rheumatic diseases. Systemic lupus erythematosus (SLE) doubles the risk for developing HZ. However, little is known about natural humoral immunity against varicella zoster virus (VZV) in patients with SLE. Hence, we compared VZV IgG antibody concentrations in a group of SLE patients with healthy controls and patients with rheumatoid arthritis (RA). Methods: n = 56 patients with SLE, n = 54 patients with RA, and n = 56 healthy controls were included in this study. The VZV IgG antibody concentration was measured using an enzyme-linked immunosorbent assay (ELISA). The antibody concentrations were compared between the groups. Results: Overall IgG antibody titers for VZV in SLE patients were comparable to healthy controls but higher when compared to patients with rheumatoid arthritis (p = 0.0012). In consequence, antibody levels in controls were higher than in RA patients (p = 0.0097). Stratification by age revealed highest titers among SLE patients in the fourth life decade (p = 0.03 for controls, p = 0.0008 for RA patients) whereas RA patients in their sixth decade had the lowest antibody concentration (p = 0.03 for controls, p = 0.04 for SLE patients). Regarding the individual HZ history, antibody levels of SLE patients with a positive history exceeded all other groups. Conclusions: Although humoral VZV immunity in SLE patients is comparable to healthy controls it seems to be pronounced in young SLE patients between 30 and 39. The lowest VZV IgG levels were found in RA patients. HZ seems to induce antibody production, particularly in patients with SLE. Immunological processes might contribute to VZV antibody levels in SLE patients, but further investigations are needed to substantiate this hypothesis. Even though the increased HZ prevalence seems to be independent of humoral immunity in SLE patients, reduced humoral immunity might contribute to HZ in RA patients. The available HZ subunit vaccination might be an appropriate way to reduce the HZ risk in patients with rheumatic diseases.

Biologic Drugs for Rheumatoid Arthritis in the Context of Biosimilars, Genetics, Epigenetics and COVID-19 Treatment

Rheumatoid arthritis (RA) affects around 1.2% of the adult population. RA is one of the main reasons for work disability and premature retirement, thus substantially increasing social and economic burden. Biological disease-modifying antirheumatic drugs (bDMARDs) were shown to be an effective therapy especially in those rheumatoid arthritis (RA) patients, who did not adequately respond to conventional synthetic DMARD therapy. However, despite the proven efficacy, the high cost of the therapy resulted in limitation of the widespread use and unequal access to the care. The introduction of biosimilars, which are much cheaper relative to original drugs, may facilitate the achievement of the therapy by a much broader spectrum of patients. In this review we present the properties of original biologic agents based on cytokine-targeted (blockers of TNF, IL-6, IL-1, GM-CSF) and cell-targeted therapies (aimed to inhibit T cells and B cells properties) as well as biosimilars used in rheumatology. We also analyze the latest update of bDMARDs' possible influence on DNA methylation, miRNA expression and histone modification in RA patients, what might be the important factors toward precise and personalized RA treatment. In addition, during the COVID-19 outbreak, we discuss the usage of biologicals in context of effective and safe COVID-19 treatment. Therefore, early diagnosing along with therapeutic intervention based on personalized drugs targeting disease-specific genes is still needed to relieve symptoms and to improve the quality of life of RA patients.

Fluctuation in anti-cyclic citrullinated protein antibody level predicts relapse from remission in rheumatoid arthritis: KURAMA cohort

Background

The positivity of anti-citrullinated protein/peptide antibodies (ACPAs) is a clinically useful diagnostic and prognostic marker in rheumatoid arthritis (RA). However, the significance of ACPA titer and its fluctuation remain unclear. This study aimed to assess the role of ACPA titer and its fluctuation on disease activity and the prognosis of RA.

Methods

Data obtained from the Kyoto University Rheumatoid Arthritis Management Alliance (KURAMA) cohort was analyzed. Patients whose ACPA was measured at least twice between 2011 and 2019 and whose ACPA was positive at least once were included in this study. The association between the clinical variable and ACPA titer or its change was investigated.

Results

ACPA titer was measured in a total of 3286 patients, 1806 of whom were ACPA-positive at least once. Among them, the ACPA titer level was measured more than once in 1355 patients. Very weak correlation was observed between the ACPA titer level and disease activity. Additionally, there was no trend in the fluctuation of ACPA titer level in each patient; ACPA titer level fluctuated in some patients, but not in others. Patients with high variable levels of ACPA titer were more likely to relapse from remission. In the analysis of two consecutive ACPA measurements, the titer changes predicted the relapse from remission within a year of the second measurement.

Conclusions

The ACPA titer level fluctuated in some patients. Very weak correlation was observed between the ACPA titer level and disease activity. Fluctuation in ACPA titer level predicted relapse from remission in patients with RA.

Supplementary information

The online version contains supplementary material available at 10.1186/s13075-020-02366-x.

Precision medicine and management of rheumatoid arthritis

Precision medicine (PM) is a very commonly used term that implies a highly individualized and tailored approach to patient management. There are, however, many layers of precision, as for example taking an appropriate patient history, or performing additional lab or imaging tests are already helping to better tailor treatments to the right patient. All this adds to the narrower definition of PM, which implies using the unique molecular characteristics of a patient for management decisions. Big data has become an essential part of PM, including as much information as possible to improve precision of disease management, although integration of multi-source data continues to be a challenge in practical application. In research big data can identify new (sub-)phenotypes in unsupervised analyses, which ultimately advance precision by allowing new targeted therapeutic approaches. We will discuss the current status of PM in rheumatoid arthritis (RA) in the management areas of diagnosis, prognosis, selection of therapy, and decision to reduce therapy. PM markers for diagnosis of RA are usually markers of RA classification rather than diagnosis, and subtypes of RA are potentially underrecognized. Prognostic precision is well established for RA, including markers of disease activity or structure, as well as autoantibodies and genetics. The choice of the right compound in a patient identified to have a poor prognosis, however, remains widely arbitrary. Finally and most recently, the most reliable markers for a safe withdrawal of therapy continue to be lower levels of disease activity and longer presence of remission.

Update on the Pathomechanism, Diagnosis, and Treatment Options for Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease that involves multiple joints bilaterally. It is characterized by an inflammation of the tendon (tenosynovitis) resulting in both cartilage destruction and bone erosion. While until the 1990s RA frequently resulted in disability, inability to work, and increased mortality, newer treatment options have made RA a manageable disease. Here, great progress has been made in the development of disease-modifying anti-rheumatic drugs (DMARDs) which target inflammation and thereby prevent further joint damage. The available DMARDs are subdivided into (1) conventional synthetic DMARDs (methotrexate, hydrochloroquine, and sulfadiazine), (2) targeted synthetic DMARDs (pan-JAK- and JAK1/2-inhibitors), and (3) biologic DMARDs (tumor necrosis factor (TNF)-α inhibitors, TNF-receptor (R) inhibitors, IL-6 inhibitors, IL-6R inhibitors, B cell depleting antibodies, and inhibitors of co-stimulatory molecules). While DMARDs have repeatedly demonstrated the potential to greatly improve disease symptoms and prevent disease progression in RA patients, they are associated with considerable side-effects and high financial costs. This review summarizes our current understanding of the underlying pathomechanism, diagnosis of RA, as well as the mode of action, clinical benefits, and side-effects of the currently available DMARDs.

Prime-boost vaccination strategy enhances immunogenicity compared to single pneumococcal conjugate vaccination in patients receiving conventional DMARDs, to some extent in abatacept but not in rituximab-treated patients

OBJECTIVE

To explore whether a prime-boost vaccination strategy, i.e., a dose of pneumococcal conjugate vaccine (PCV) and a dose of 23-valent polysaccharide vaccine (PPV23), enhances antibody response compared to single PCV dose in patients with inflammatory rheumatic diseases treated with different immunosuppressive drugs and controls.

METHODS

Patients receiving rituximab (n = 30), abatacept (n = 23), monotherapy with conventional disease-modifying antirheumatic drugs (cDMARDs, methotrexate/azathioprine/mycophenolate mofetil, n = 27), and controls (n = 28) were immunized with a dose PCV followed by PPV23 after ≥ 8 weeks. Specific antibodies to 12 serotypes included in both vaccines were determined using a multiplex microsphere immunoassay in blood samples before and 4-8 weeks after each vaccination. Positive antibody response was defined as ≥ 2-fold increase from pre- to postvaccination serotype-specific IgG concentration and putative protective level as IgG ≥ 1.3 μg/mL. The number of serotypes with positive antibody response and IgG ≥ 1.3 μg/mL, respectively, after PCV and PCV + PPV23 were compared within each treatment group and to controls. Opsonophagocytic activity (OPA) assay was performed for serotypes 6B and 23F.

RESULTS

Compared to single-dose PCV, prime-boost vaccination increased the number of serotypes with positive antibody response in patients with abatacept, cDMARDs, and controls (p = 0.02, p = 0.01, and p = 0.01), but not in patients on rituximab. After PCV + PPV23, the number of serotypes with positive antibody response was significantly lower in all treatment groups compared to controls but lowest in rituximab, followed by the abatacept and cDMARD group (p < 0.001). Compared to PCV alone, the number of serotypes with putative protective levels after PCV + PPV23 increased significantly only in patients in cDMARDs (p = 0.03) and controls (p = 0.001). Rituximab treatment was associated with large reduction (coefficient - 8.6, p < 0.001) and abatacept or cDMARD with moderate reductions (coefficients - 1.9 and - 1.8, p = 0.005, and p < 0.001) in the number of serotypes with positive antibody response to PCV + PPV23 (multivariate linear regression model). OPA was reduced in rituximab (Pn6B and Pn23F, p < 0.001), abatacept (Pn23F, p = 0.02), and cDMARD groups (Pn6B, p = 0.02) compared to controls.

CONCLUSIONS

Prime-boost strategy enhances immunogenicity compared to single pneumococcal conjugate vaccination in patients with inflammatory rheumatic diseases receiving cDMARDs, to some extent in abatacept but not in patients on rituximab. Pneumococcal vaccination should be encouraged before the initiation of treatment with rituximab.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03762824. Registered on 4 December 2018, retrospectively registered.

Abatacept reduces disease activity of rheumatoid arthritis independently of modulating anti-citrullinated peptide antibody production

Abatacept may exert its clinical effect on rheumatoid arthritis (RA) by suppressing anti-cyclic citrullinated peptide (CCP) antibody production. This study was undertaken to test this hypothesis by examining the changes of disease activity of RA and anti-CCP antibody levels over time after starting abatacept. Sixty Japanese RA patients who started abatacept were included in this multicenter, prospective observational study. Simple Disease Activity Index (SDAI) and anti-CCP antibody levels were evaluated at 12, 24, and 52 weeks. The mean SDAI score significantly decreased within 12 weeks after starting abatacept and was maintained thereafter. On the contrary, the mean anti-CCP antibody levels did not change until 52 weeks. At the individual level, there were substantial changes of anti-CCP antibody levels, but these were not correlated with the changes of disease activity at any time points. Thus, abatacept reduces the disease activity of RA independently of modulating anti-CCP antibody production.

CTLA-4: From mechanism to autoimmune therapy

CD28 and CTLA-4 are both important stimulatory receptors for the regulation of T cell activation. Because receptors share common ligands, B7.1 and B7.2, the expression and biological function of CTLA-4 is important for the negative regulation of T cell responses. Therefore, elimination of CTLA-4 can result in the breakdown of immune tolerance and the development of several diseases such as autoimmunity. Inhibitory signals of CTLA-4 suppress T cell responses and protect against autoimmune diseases in many ways. In this review, we summarize the structure, expression and signaling pathway of CTLA-4. We also highlight how CTLA-4 defends against potentially self-reactive T cells. Finally, we discuss how the CTLA-4 regulates a number of autoimmune diseases that indicate manipulation of this inhibitory molecule is a promise as a strategy for the immunotherapy of autoimmune diseases.

The B side of rheumatoid arthritis pathogenesis

In the last years, a dramatic amount of research has been performedincreasing the knowledge about the biological mechanism underpinning Rheumatoid Arthritis (RA) inflammation, putting B lymphocytes in the center of RA pathogenesis. Nowadays, B cell phenotypes and autoantibodies positivity arose as important biomarkers in early and long-standing disease. Moreover, comparative analysis of peripheral blood and synovial tissue compartments enables the identification of novel physiopathological mechanisms promoting inflammation. In this narrative review we will discuss the biological relevance of B cell derived autoimmunity and in RA course, from disease onset to remission achievement.

Association of Changes in Anticitrullinated Protein Antibody Levels With Resource Use and Disease Activity Measures in Rheumatoid Arthritis Patients a US Observational Cohort

PURPOSE

Anticitrullinated protein antibody (ACPA) concentration, beyond ACPA positivity, is indicative of more aggressive radiographic progression in patients with rheumatoid arthritis (RA). However, there is limited information on the association of changes in ACPA with resource use measures and/or disease activity measures. We evaluate associations between changes in levels of ACPA and outcomes, including durable medical equipment (DME) use, hospitalizations, and disease activity, in patients with established RA.

METHODS

Patients from the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study who had ACPA measurements at baseline and month 12 were included. Changes in ACPA levels from baseline to month 12 were categorized as a decrease (<-10%), no change (-10% to +10%), or increase (>+10%). DME use and hospitalizations were assessed twice yearly using patient questionnaires; disease activity was assessed annually. Binary multivariate logistic regression was used to analyze the association between changes in ACPA levels and DME use and hospitalizations; linear regression was used to assess the association with disease activity.

FINDINGS

Of 840 patients included in the analysis, 291 (34.6%), 266 (31.7%), and 283 (33.7%) had a decrease, no change, or increase in ACPA levels, respectively. A decrease in ACPA levels was associated with a reduction in DME use (adjusted odds ratio [aOR] = 0.64; 95% CI, 0.44-0.93; P = 0.02) and hospitalizations (aOR = 0.62; 95% CI, 0.41-0.95; P = 0.03) versus no change or increase. Adjusted mean changes in disease activity score in 28 joints (C-reactive protein), total and swollen joint counts, and pain scores were significantly greater in patients with decreased ACPA levels versus those with no change or increase (P < 0.05).

IMPLICATIONS

Among patients with RA, reductions in ACPA levels of >10% were associated with reductions in DME use, hospitalizations, and disease activity. ClinicalTrials.gov identifier: NCT01793103.

Abatacept modulates CD80 and CD86 expression and memory formation in human B-cells

BACKGROUND

Cytotoxic T lymphocyte antigen-4 (CTLA-4) limits T-cell activation and is expressed on T-regulatory cells. Human CTLA-4 deficiency results in severe immune dysregulation. Abatacept (CTLA-4 Ig) is approved for the treatment of rheumatoid arthritis (RA) and its mechanism of action is attributed to effects on T-cells. It is known that CTLA-4 modulates the expression of its ligands CD80 and CD86 on antigen presenting cells (APC) by transendocytosis. As B-cells express CD80/CD86 and function as APC, we hypothesize that B-cells are a direct target of abatacept.

OBJECTIVES

To investigate direct effects of abatacept on human B-lymphocytes in vitro and in RA patients.

METHODS

The effect of abatacept on healthy donor B-cells' phenotype, activation and CD80/CD86 expression was studied in vitro. Nine abatacept-treated RA patients were studied. Seven of these were followed up to 24 months, and two up to 12 months only and treatment response, immunoglobulins, ACPA, RF concentrations, B-cell phenotype and ACPA-specific switched memory B-cell frequency were assessed.

RESULTS

B-cell development was unaffected by abatacept. Abatacept treatment resulted in a dose-dependent decrease of CD80/CD86 expression on B-cells in vitro, which was due to dynamin-dependent internalization. RA patients treated with abatacept showed a progressive decrease in plasmablasts and serum IgG. While ACPA-titers only moderately declined, the frequency of ACPA-specific switched memory B-cells significantly decreased.

CONCLUSIONS

Abatacept directly targets B-cells by reducing CD80/CD86 expression. Impairment of antigen presentation and T-cell activation may result in altered B-cell selection, providing a new therapeutic mechanism and a base for abatacept use in B-cell mediated autoimmunity.

Th17 and Th1 Lymphocytes in Oligoarticular Juvenile Idiopathic Arthritis

In the last years much attention has focused on the Th17 and Th1 phenotypes and on their pathogenic role in juvenile idiopathic arthritis, investigating how the cytokines produced by T helper cells act on resident cells on the synovia and which signal transduction pathways regulate Th17 cells proliferation and plasticity. In this context, an important milestone was represented by the identification of the non-classic Th1 phenotype, developed from the shift of Th17 cells. The cytokine TNF-α, beyond its well-known proinflammatory activity is involved in this process and this is one of the reasons why the TNF-α inhibitors are widely used in the treatment of juvenile idiopathic arthritis patients.

Free light chains and autoimmunity

The study of free light chains (FLCs) has grown as area of enormous interest for many clinicians with the aim of disclosing the exact biological role and potential use of FLCs in the clinical routine. Moreover, the attention given to immunological functions of FLCs has sparked a new light into their pathogenic contribution in different chronic autoimmune-based inflammatory diseases. The release of intracellular antigens following cell death or ineffective clearance of apoptotic debris, modification of self-antigens, and molecular mimicry may trigger the production of immunoglobulins after activation and polyclonal expansion of B cells, by which FLCs are released. The discovery of polyclonal FLCs as potential biomarkers started with the observation of their increased concentrations in a variety of biological fluids related to patients with autoimmune diseases. This review deals with the use of polyclonal FLCs for identifying severity and monitoring outcome after treatment in some autoimmune diseases, namely systemic lupus erythematosus, myasthenia gravis, systemic sclerosis, rheumatoid arthritis and Sjögren's syndrome, as supported by the fact that levels of FLCs correlate with both B cell activation markers and other specific markers of disease activity. In a near future, following the evidence shown, FLCs might probably work as early prognostic markers of severity and also as indicators of response to treatment or early assessment of relapse in selected autoimmune diseases.

IgG Anti-ghrelin Immune Complexes Are Increased in Rheumatoid Arthritis Patients Under Biologic Therapy and Are Related to Clinical and Metabolic Markers

Rheumatoid arthritis (RA) is a systemic autoimmune disease associated with increased risk of cardiovascular disease and metabolic alterations. The mechanisms underlying these alterations remain unclear. Ghrelin is a gastrointestinal hormone with potent effects on food intake, body weight, metabolism, and immune response. Recent studies reported the presence of anti-ghrelin autoantibodies in healthy subjects and the levels and affinity of these autoantibodies were altered in anorectic and obese individuals. In this cross-sectional study we analyzed anti-ghrelin autoantibodies in RA patients and evaluated its relationship with clinical, body-composition and metabolic parameters. Clinical measurements of RA patients included the disease activity score-28 (DAS-28), inflammatory biomarkers, autoantibodies (RF and anti-CCP), body composition, glucose and lipid profile. Serum ghrelin levels were measured by enzyme-linked immunosorbent assay (ELISA). Free and total anti-ghrelin autoantibodies quantification (IgG and IgA isotypes) was performed by in-house ELISA. RA patients had lower IgG anti-ghrelin autoantibodies levels and higher immune complexes percentage (IgG+ghrelin) compared to the control group, while the IgA anti-ghrelin autoantibodies showed no significant differences. In the bivariate analysis, the percentage of IgG anti-ghrelin immune complexes positively correlated with BMI and ghrelin whereas in the multivariate regression model, the variables associated were DAS-28, body weight, visceral fat, LDL-C and TG (R ² = 0.72). The percentage of IgA anti-ghrelin immune complexes positively correlated with RF and anti-CCP and the multivariate regression model showed an association with RF and body fat percentage (R ² = 0.22). Our study shows an increased percentage of IgG anti-ghrelin immune complexes in RA patients despite ghrelin levels were similar in both groups, suggesting an increase in the affinity of these autoantibodies toward ghrelin. The associations found in the multiple regression analysis for anti-ghrelin immune complexes support the previously reported functions of these natural autoantibodies as carriers and modulators of the stability and physiological effect of the hormone. However, in RA both the disease activity and the RF appear to influence the formation of these anti-ghrelin immune complexes.

Factors associated with the achievement of biological disease-modifying antirheumatic drug-free remission in rheumatoid arthritis: the ANSWER cohort study

Background

Clinical remission can be maintained after the discontinuation of biological disease-modifying antirheumatic drugs (bDMARDs) in some patients with rheumatoid arthritis (RA) (bDMARD-free remission (BFR)). It is unknown which bDMARD is advantageous for achieving BFR or under which conditions BFR can be considered. This study aimed to determine the factors associated with BFR achievement in clinical practice.

Methods

Patients with RA were enrolled from a Japanese multicenter observational registry. Patients with RA who achieved clinical remission (Disease Activity Score 28—C-reactive protein < 2.3) at the time of bDMARD discontinuation were included. Serial disease activities and treatment changes were followed up. BFR was considered to have failed if the disease activity exceeded the remission cutoff value or if bDMARDs were restarted.

Results

Overall, 181 RA patients were included. BFR was maintained in 21.5% of patients at 1 year after bDMARD discontinuation. BFR was more successfully achieved after discontinuation of anti-tumor necrosis factor (TNF) monoclonal antibodies (TNFi(mAb)) (infliximab, adalimumab, and golimumab), followed by CTLA4-Ig (abatacept), soluble TNF receptor or Fab fragments against TNF fused with polyethylene glycol (etanercept and certolizumab), and anti-interleukin-6 receptor Ab (tocilizumab). After multivariate analysis, sustained remission (> 6 months), Boolean remission, no glucocorticoid use at the time of bDMARD discontinuation, and use of TNFi(mAb) or CTLA4-Ig remained as independent factors associated with BFR.

Conclusions

BFR can be achieved in some patients with RA after bDMARD discontinuation in clinical practice. Use of TNFi(mAb) or CTLA4-Ig, sustained remission, Boolean remission, and no glucocorticoid use at the time of bDMARD discontinuation are advantageous for achieving BFR.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1673-1) contains supplementary material, which is available to authorized users.

Predictive factors for structural remission using abatacept: Results from the ABROAD study

OBJECTIVE

To investigate the effect of abatacept (ABA) on preventing joint destruction in biological disease-modifying anti-rheumatic drug (bDMARD)-naïve rheumatoid arthritis (RA) patients in real-world clinical practice.

PATIENTS AND METHODS

RA patients were collected from the ABROAD (ABatacept Research Outcomes as a First-line Biological Agent in the Real WorlD) study cohort. They had moderate or high disease activity and were treated with ABA as a first-line bDMARD. Radiographic change between baseline and 1 year after ABA treatment was assessed with the van der Heijde's modified Total Sharp Score (mTSS). Predictive factors for structural remission (St-REM), defined as ΔmTSS ≤0.5/year, were determined.

RESULTS

Among 118 patients, 81 (67.5%) achieved St-REM. Disease duration <3 years (odds ratio (OR) = 3.152, p = .007) and slower radiographic progression (shown as 'baseline mTSS/year <3', OR = 3.727, p = .004) were independently significant baseline predictive factors for St-REM irrespective of age and sex. St-REM prevalence increased significantly if clinical remission based on the Simplified Disease Activity Index was achieved at least once until 24 weeks after ABA treatment.

CONCLUSION

Shorter disease duration, smaller radiographic progression at baseline, and rapid clinical response were predictive factors for sustained St-REM after ABA therapy in bDMARD-naïve RA patients.

Switched Memory B Cells Are Increased in Oligoarticular and Polyarticular Juvenile Idiopathic Arthritis and Their Change Over Time Is Related to Response to Tumor Necrosis Factor Inhibitors

OBJECTIVE

To investigate whether abnormalities in B cell subsets in patients with juvenile idiopathic arthritis (JIA) correlate with clinical features and response to treatment.

METHODS

A total of 109 patients diagnosed as having oligoarticular JIA or polyarticular JIA were enrolled in the study. B cell subsets in peripheral blood and synovial fluid were analyzed by flow cytometry.

RESULTS

Switched memory B cells were significantly increased in patients compared to age-matched healthy controls (P < 0.0001). When patients were divided according to age at onset of JIA, in patients with early-onset disease (presenting before age 6 years) the expansion in switched memory B cells was more pronounced than that in patients with late-onset disease and persisted throughout the disease course. In longitudinal studies, during methotrexate (MTX) treatment, regardless of the presence or absence of active disease, the number of switched memory B cells increased significantly (median change from baseline 36% [interquartile range {IQR} 15, 66]). During treatment with MTX plus tumor necrosis factor inhibitors (TNFi), in patients maintaining disease remission, the increase in switched memory B cells was significantly lower than that in patients who experienced active disease (median change from baseline 4% [IQR -6, 32] versus 41% [IQR 11, 73]; P = 0.004). The yearly rate of increases in switched memory B cells was 1.5% in healthy controls, 1.2% in patients who maintained remission during treatment with MTX plus TNFi, 4.7% in patients who experienced active disease during treatment with MTX plus TNFi, and ~4% in patients treated with MTX alone.

CONCLUSION

Switched memory B cells expand during the disease course at a faster rate in JIA patients than in healthy children. This increase is more evident in patients with early-onset JIA. TNFi treatment inhibits this increase in patients who achieve and maintain remission, but not in those with active disease.

Real-world predictors of 12-month intravenous abatacept retention in patients with rheumatoid arthritis in the ACTION observational study

INTRODUCTION

An understanding of real-world predictors of abatacept retention is limited. We analysed retention rates and predictors of abatacept retention in biologic-naïve and biologic-failure patients in a 12-month interim analysis of the 2-yearAbataCepTIn rOutiNe clinical practice (ACTION) study.

METHODS

ACTION was an international, observational study of patients with moderate-to-severe rheumatoid arthritis (RA) who initiated intravenous abatacept. In this 12-month interim analysis, crude abatacept retention rates, predictors of retention and European League Against Rheumatism (EULAR) response were evaluated in both biologic-naïve and biologic-failure patients. Retention by rheumatoid factor (RF) and anti-cyclic citrullinated peptide (CCP) status was also assessed, in patients with or without baseline radiographic erosions, and by body mass index (BMI).

RESULTS

Overall, 2350/2364 enrolled patients were evaluable (674 biologic naїve; 1676 biologic failure). Baseline characteristics were largely similar in biologic-naïve and biologic-failure groups. Crude retention rates (95% CI) at 12 months were significantly higher in biologic-naїve (78.1%(74.7% to 81.2%)) versus biologic-failure patients (69.9%(67.6% to 72.1%); P<0.001). RF/anti-CCP double positivity predicted higher retention in both patient groups, and remained associated with higher retention in patients with erosive disease. BMI did not impact abatacept retention in either patient group, irrespective of RF/anti-CCP serostatus. Good/moderate EULAR response rate at 12 months was numerically higher in biologic-naїve (83.8%) versus biologic-failure (73.3%) patients. There were no new safety signals.

CONCLUSION

High levels of intravenous abatacept retention in clinical practice were confirmed, particularly in biologic-naïve patients, including in those with poor RA prognostic factors. Retention was unaffected by BMI, regardless of RF/anti-CCP serostatus.

TRIAL REGISTRATION NUMBER

NCT02109666; retrospectively registered 8 April 2014.

Effect of Anticitrullinated Protein Antibody Status on Response to Abatacept or Antitumor Necrosis Factor-α Therapy in Patients with Rheumatoid Arthritis: A US National Observational Study

Objective.

Assess whether baseline anticyclic citrullinated peptide antibodies (anti-CCP) status is associated with treatment response in patients with rheumatoid arthritis (RA) initiating abatacept (ABA) or a tumor necrosis factor-α inhibitor (TNFi).

Methods.

Using the Corrona RA registry, patients were identified who initiated ABA or a TNFi (June 2004–January 2015), had a followup visit 6 months (± 3 mos) after initiation, and anti-CCP measured at or prior to initiation. Primary outcome was mean change in Clinical Disease Activity Index (CDAI) from initiation to 6 months. Treatment response was evaluated based on a typical patient profile (female, aged 57 yrs, body mass index of 30 kg/m2, baseline CDAI of 20, 1 prior biologic, and no comorbidities other than RA). Secondary outcomes included remission and low disease activity.

Results.

There were 566 ABA initiators [anti-CCP+ (≥ 20 units/ml): n = 362; anti-CCP− (< 20 units/ml): n = 204] and 1715 TNFi initiators (anti-CCP+: n = 1113; anti-CCP−: n = 602). Differences between treatment groups included baseline disease duration, CDAI, and prior biologic use. At 6 months, anti-CCP+ ABA initiators were associated with significantly greater CDAI response versus anti-CCP− ABA initiators; no significant difference was observed for TNFi initiators. When considering a typical RA patient profile, CDAI response was greater in anti-CCP+ versus anti-CCP− ABA initiators; anti-CCP+ versus anti-CCP− TNFi initiators were similar. Secondary outcome responses were also greater in anti-CCP+ versus anti-CCP− ABA initiators; TNFi initiators did not differ by anti-CCP status.

Conclusion.

In a US-based clinical practice setting, anti-CCP status was associated with a differential treatment response to ABA, but not TNFi.

Right drug, right patient, right time: aspiration or future promise for biologics in rheumatoid arthritis?

Individualising biologic disease-modifying anti-rheumatic drugs (bDMARDs) to maximise outcomes and deliver safe and cost-effective care is a key goal in the management of rheumatoid arthritis (RA). Investigation to identify predictive tools of bDMARD response is a highly active and prolific area of research. In addition to clinical phenotyping, cellular and molecular characterisation of synovial tissue and blood in patients with RA, using different technologies, can facilitate predictive testing. This narrative review will summarise the literature for the available bDMARD classes and focus on where progress has been made. We will also look ahead and consider the increasing use of 'omics' technologies, the potential they hold as well as the challenges, and what is needed in the future to fully realise our ambition of personalised bDMARD treatment.

Abatacept: A Review in Rheumatoid Arthritis

The biological DMARD (bDMARD) abatacept (Orencia^®), a recombinant fusion protein, selectively modulates a co-stimulatory signal necessary for T-cell activation. In the EU, abatacept is approved for use in patients with highly active and progressive rheumatoid arthritis (RA) not previously treated with methotrexate. Abatacept is also approved for the treatment of moderate to severe active RA in patients with an inadequate response to previous therapy with at least one conventional DMARD (cDMARD), including methotrexate or a TNF inhibitor. In phase III trials, beneficial effects on RA signs and symptoms, disease activity, structural damage progression and physical function were seen with intravenous (IV) or subcutaneous (SC) abatacept regimens, including abatacept plus methotrexate in methotrexate-naive patients with early RA and poor prognostic factors, and abatacept plus methotrexate or other cDMARDs in patients with inadequate response to methotrexate or TNF inhibitors. Benefits were generally maintained during longer-term follow-up. Absolute drug-free remission rates following withdrawal of all RA treatments were significantly higher with abatacept plus methotrexate than with methotrexate alone. Both IV and SC abatacept were generally well tolerated, with low rates of immunogenicity. Current evidence therefore suggests that abatacept is a useful treatment option for patients with RA.

Brief Report: Association of Rheumatoid Factor and Anti-Citrullinated Protein Antibody Positivity With Better Effectiveness of Abatacept: Results From the Pan-European Registry Analysis

OBJECTIVE

To investigate the role of rheumatoid factor (RF) status and anti-citrullinated peptide antibody (ACPA) status as predictors of abatacept (ABA) effectiveness in patients with rheumatoid arthritis (RA).

METHODS

We conducted a pooled analysis of data from 9 observational RA registries in Europe (ARTIS [Sweden], ATTRA [Czech Republic], BIOBADASER [Spain], DANBIO [Denmark], GISEA [Italy], NOR-DMARD [Norway], ORA [France], Reuma.pt [Portugal], and SCQM-RA [Switzerland]). Inclusion criteria were a diagnosis of RA, initiation of ABA treatment, and available information on RF and/or ACPA status. The primary end point was continuation of ABA treatment. Secondary end points were ABA discontinuation for ineffectiveness or adverse events and response rates at 1 year (good or moderate response according to the European League Against Rheumatism criteria with LUNDEX adjustment for treatment continuation). Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the study end points in relation to RF and ACPA status were calculated.

RESULTS

We identified 2,942 patients with available data on RA-associated autoantibodies; data on RF status were available for 2,787 patients (77.0% of whom were RF positive), and data on ACPA status were available for 1,903 patients (71.3% of whom were ACPA positive). Even after adjustment for sociodemographic and disease- and treatment-related confounders, RF and ACPA positivity were each associated with a lower risk of ABA discontinuation for any reason (HR 0.79 [95% CI 0.69-0.90], P < 0.001 and HR 0.78 [95% CI 0.68-0.90], P < 0.001, respectively), compared to RF-negative and ACPA-negative patients. Similar associations with RF and ACPA were observed for discontinuation of ABA treatment due to ineffectiveness, with HRs of 0.72 (95% CI 0.61-0.84) and 0.74 (95% CI 0.62-0.88), respectively (both P < 0.001).

CONCLUSION

Our results strongly suggest that positivity for RF or ACPA is associated with better effectiveness of ABA therapy.

Interleukin-10-producing LAG3+ regulatory T cells are associated with disease activity and abatacept treatment in rheumatoid arthritis

BACKGROUND

Regulatory T cells (Tregs) play a role in the suppression of inflammation in autoimmune diseases, and lymphocyte activation gene 3 (LAG3) was reported as a marker of interleukin (IL)-10-producing Tregs. We aimed to clarify the function of human IL-10-producing CD4⁺CD25^-LAG3⁺ T cells (LAG3⁺ Tregs) and their association with rheumatoid arthritis (RA).

METHODS

LAG3⁺ Tregs of human peripheral blood mononuclear cells (PBMCs) were cultured with B cells and follicular helper T cells to examine antibody suppression effects. The frequency of LAG3⁺ Tregs was evaluated in peripheral blood samples from 101 healthy donors and 85 patients with RA. In patients treated with abatacept, PBMC samples were analyzed before and after treatment. Naive CD4⁺ T cells were sorted and cultured in the presence of abatacept, followed by flow cytometric analysis and function assays.

RESULTS

LAG3⁺ Tregs produced high amounts of IL-10 and interferon-γ, and they suppressed B-cell antibody production more strongly than CD25⁺ Tregs. Cell-to-cell contact was required for the suppressive function of LAG3⁺ Tregs. The frequency of LAG3⁺ Tregs was lower in patients with RA, especially those with higher Clinical Disease Activity Index scores. LAG3⁺ Tregs significantly increased after 6 months of abatacept treatment, whereas CD25⁺ Tregs generally decreased. Abatacept treatment in vitro conferred LAG3 and EGR2 expression on naive CD4⁺ T cells, and abatacept-treated CD4⁺ T cells exhibited suppressive activity.

CONCLUSIONS

IL-10-producing LAG3⁺ Tregs are associated with the immunopathology and therapeutic response in RA. LAG3⁺ Tregs may participate in a mechanism for the anti-inflammatory and immune-modulating effects of targeted therapy for costimulation.

The role of anticitrullinated protein antibodies in the early stages of rheumatoid arthritis

PURPOSE OF REVIEW

This review provides an update on the recent discoveries on the role of anticitrullinated protein antibodies (ACPA) in early rheumatoid arthritis (RA).

RECENT FINDINGS

RA is characterized by an immune response against posttranslationally modified proteins, in particular citrullinated proteins. Recent studies have found that the ACPA response matures shortly before clinical disease manifests itself and is characterized by an increase in titre, isotype switching, antigen-recognition profile, and a change in the Fc-glycosylation pattern. To date, many citrullinated autoantigens have been identified and novel studies suggest that the human leucocyte antigen class II locus may directly influence the maturation of the ACPA response via antigen-specific T cells. Clinical studies have demonstrated that effective treatment of arthritis can lead to reduced ACPA levels or a change in composition of ACPA. In addition to ACPA, autoantibodies targeting other posttranslational modifications have been identified and may be associated with disease prognosis.

SUMMARY

Key studies have demonstrated that autoimmunity against citrullinated proteins is already present in preclinical RA and matures over time. Future studies are required to reveal whether autoantibodies and the B cells that produce them play a role in disease development or can function as biomarkers for disease maturation.

Anti-citrullinated peptide antibodies and their value for predicting responses to biologic agents: a review

Anti-citrullinated peptide antibodies (ACPAs) play an important pathogenic role both at the onset and during the disease course. These antibodies precede the clinical appearance of rheumatoid arthritis (RA) and are associated with a less favorable prognosis, both clinically and radiologically. The objective of this work was to conduct a comprehensive review of studies published through September 2015 of ACPAs' role as a predictor of the therapeutic response to the biological agents in RA patients. The review also includes summary of the biology and detection of ACPAs as well as ACPAs in relation to joint disease and CV disease and the possible role of seroconversion. The reviews of studies examining TNF inhibitors and tocilizumab yielded negative results. In the case of rituximab, the data indicated a greater probability of clinical benefit in ACPA(+) patients versus ACPA(-) patients, as has been previously described for rheumatoid factor. Nonetheless, the effect is discreet and heterogeneous. Another drug that may have greater effectiveness in ACPA(+) patients is abatacept. Some studies have suggested that the drug is more efficient in ACPA(+) patients and that those patients show greater drug retention. In a subanalysis of the AMPLE trial, patients with very high ACPA titers who were treated with abatacept had a statistically significant response compared to patients with lower titers. In summary, the available studies suggest that the presence of or high titers of ACPA may predict a better response to rituximab and/or abatacept. Evidence regarding TNFi and tocilizumab is lacking. However, there is a lack of studies with appropriate designs to demonstrate that some drugs are superior to others for ACPA(+) patients.

JAK1-STAT3 blockade by JAK inhibitor SHR0302 attenuates inflammatory responses of adjuvant-induced arthritis rats and decreases Th17 and total B cells

OBJECTIVE

To investigate the effects of JAK inhibitor (SHR0302) on adjuvant-induced arthritis (AA) rats and the partial mechanisms focused on T, B lymphocyte subsets through JAK1-STAT3 pathway, including Th17, Treg, total B cells and memory B cells.

METHODS

Animals were divided randomly into normal control, AA, SHR0302 (0.3,1.0, 3.0mg/kg) and MTX. The effects of SHR0302 on AA rats by evaluating arthritis index, arthritis global assessment and paw swelling degree, histopathology of joint and spleen. We examined the proliferation of T, B and FLS. Th17, Treg, total B and memory B cell proportion was measured by flow cytometry. Cytokines TNF-α, IL-1β, IL-10, IL-17 and antibody IgG1, IgG2a levels in serum were measured by Elisa. The expression of p-JAK1 and p-STAT3 was measured by western blot.

RESULTS

SHR0302 suppressed the severity of AA rats by attenuating the arthritis index, arthritis global assessment and paw swelling degree, and alleviated histopathology of spleen and joint of AA rats. SHR0302 can inhibit the proliferation of T, B and FLS, and down-regulated cytokines TNF-α, IL-1β, IL-17 and antibody IgG1, IgG2a levels, and suppressed the proportion of Th17 and total B, and inhibited JAK1-STAT3 phosphorylation. There was no significant effect on Treg function and memory B cell proportion.

CONCLUSION

SHR0302 may attenuate the severity of AA rats, partially through reducing Th17 function and total B cell proportion by inhibiting JAK1-STAT3 phosphorylation.

Predictive factors of abatacept therapy discontinuation in patients with rheumatoid arthritis

The aim of this paper was to look for predictors of abatacept (ABA) therapy discontinuation in patients with rheumatoid arthritis (RA). Seventy-one RA patients treated with ABA were followed up. Demographical, clinical, and laboratory parameters of the patients, including peripheral blood T and B cell populations, different rheumatoid factor and anti-cyclic citrullinated peptide autoantibodies isotypes, and serum free light chains were evaluated. Comparing patients who discontinued ABA with those still in therapy we observed: a higher proportion of smokers (51.9 vs 25.6 %; p = 0.03); a non significant lower proportion of anti-cyclic citrullinated peptide positivity (76 vs 89.5 %; p = 0.13); a lower proportion of terminally differentiated effector memory cells (TDEM) among total CD8+ T lymphocytes at baseline (22.0 % (7.8-39.2) vs 38.7 % (20.7-55.9); p = 0.002). Logistic multivariate analysis showed that only the proportion of CD8+TDEM T cells was an independent predictive factor of therapy discontinuation (OR (95 % IC) = 6.2 (1.2 to 30.8); p = 0.026). Receiver-operating characteristic analysis showed a significant performance of this biomarker for prediction of therapy discontinuation (using a cut-off of 30.6 %: AUC: 0.760 ± 0.07; p = 0.002). Patients with a low proportion of CD8+TDEM at baseline had a higher probability of discontinuing the treatment during time (log-rank test: p < 0.01). T cell characterization for identification of TDEM CD8+ T cells might be a useful test to predict discontinuation of ABA therapy.