Efficacy and safety of iguratimod on patients with primary Sjögren's syndrome: a randomized, placebo-controlled clinical trial

The Mechanism of Immune Intervention by Iguratimod in Oral Lichen Planus Patients: An In Vitro Experimental Study

BACKGROUND

Oral lichen planus (OLP) is a T cell-mediated immune disease. Iguratimod (IGU) is a novel immunomodulatory agent for rheumatoid arthritis. No studies have been reported on the mechanism of IGU in the treatment of OLP, which deserves investigation.

METHODS

Samples were collected from two batches of non-erosive OLP, erosive OLP (EOLP) patients and healthy control subjects. In the first batch, the effects of IGU or the same volume of dimethyl sulfoxide (DMSO) on proliferation, apoptosis and migration of peripheral blood T lymphocytes (PBL T) were examined by CCK-8, flow cytometry and transwell assay respectively. The levels of IL-6, IL-17, TNF-α, TGF-β and IL-10 were measured by enzyme-linked immunosorbent assay. In the second batch, the percentages of Th17 and Treg cells were determined by flow cytometry in peripheral blood mononuclear cells after IGU or DMSO stimulation.

RESULTS

Compared with the control, IGU promoted apoptosis and inhibited migration, but had no significant effect on the proliferation of PBL T in OLP. IL-6, IL-17 and TNF-α were decreased in OLP. TGF-β and IL-10 showed an upward trend in the IGU-treated EOLP. IGU decreased Th17 in OLP and reduced Th17/Treg ratio in EOLP. The percentage of Treg cells showed an upregulated trend but the difference was not statistically significant.

CONCLUSION

IGU may intervene in the immune response of OLP by affecting functions of PBL T, improving the balance of Th17/Treg and regulating related cytokines.

Iguratimod Alleviates Experimental Sjögren's Syndrome by Inhibiting NLRP3 Inflammasome Activation

Iguratimod (T-614) is a compound widely used as anti-rheumatic drug. This study investigated the effect and underlying mechanism of T-614 on experimental Sjögren's syndrome (ESS). ESS mice model was established by injection of submandibular gland protein. Mice were randomly divided into control, experimental Sjögren's syndrome (ESS), ESS + T-614 (10 mg/kg), ESS + T-614 (20 mg/kg), and ESS + T-614 (30 mg/kg) groups. Human submandibular gland (HSG) were cultured with 0, 0.5, 5, or 50 μg/ml T-614 in the absence or presence of interferon-α (IFN-α). Haematoxylin and eosin (H&E) and cytokine levels were used to detect immune cells activation in submandibular glands. Apoptosis in submandibular glands tissues and cells was determined by TUNEL and flow cytometry. Apoptosis and NLRP3 inflammasome-related proteins were detected by western blotting. T-614 treatment attenuated submandibular gland damage in ESS mice. T-614 administration inhibited submandibular gland cell apoptosis in ESS mice. Furthermore, T-614 blocked inflammatory factor levels and NLRP3 inflammasome activation in the submandibular glands. In vitro, results corroborated that T-614 could protect HSG cells from IFN-α-induced cell apoptosis and inflammation by inhibiting NLRP3 inflammasome activation. Our results expounded that T-614 alleviated ESS by inhibiting NLRP3 inflammasome activation.

Simultaneous determination of iguratimod and its metabolite in rat plasma using a UPLC-MS/MS method: Application for drug-drug interaction

This aim of the work was to establish an acceptable sensitive assay based on ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for quantitatively analyzing the plasma concentrations of iguratimod (IGR) and its metabolite M2 in rats, and to further investigate the effect of fluconazole on the pharmacokinetics of IGR and M2. The mobile phase consisted of acetonitrile and water with 0.1% formic acid, was used to separate IGR, M2 and internal standard (IS) fedratinib on a UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) with the flow rate of 0.4 mL/min. Positive ion mode and multiple reaction monitoring (MRM) were used to construct the quantitative analysis. The calibration standard of IGR and M2 covered 2-10000 and 1-1000 ng/mL respectively, with the lower limit of quantification (LLOQ) as 2 ng/mL and 1 ng/mL respectively. In addition, selectivity, recovery, accuracy, precision, matrix effect and stability of the method validation program were well accepted in this work. Subsequently, this approach was used to assess the effect of fluconazole on the pharmacokinetics of IGR and M2 in rats. In the presence of 20 mg/kg fluconazole (experimental group), we found the main pharmacokinetic parameters were significantly altered when compared with 2.5 mg/kg IGR alone (control group). Among them, AUC(0-∞) and Cmax of IGR in the experimental group was 1.43 and 1.08 times higher than that of the control group, respectively. Moreover, we also found that the other main pharmacokinetic parameters of M2 had no significant changes, except t1/2z and Tmax. In conclusion, fluconazole significantly altered the main pharmacokinetics of IGR and M2 in rats. It implys that we should pay more attention to the adverse reaction of IGR when the concomitant use of fluconazole and IGR occur in the future clinical practice.

Identification of outcome domains in primary Sjögren's disease: A scoping review by the OMERACT Sjögren disease working group

OBJECTIVES

Sjögren's disease (SjD) is a heterogenous disease with a wide range of manifestations, ranging from symptoms of dryness, fatigue, and pain, to systemic involvement. Considerable advances have been made to evaluate systemic activity or patient-reported outcomes, but most of the instruments were not able to assess all domains of this multifaceted disease. The aim of this scoping review was to generate domains that have been assessed in randomized controlled trials, as the first phase of the Outcome Measures in Rheumatology (OMERACT) process of core domain set development.

METHODS

We systematically searched Medline (Pubmed) and EMBASE between 2002 and March 2023 to identify all randomized controlled trials assessing relevant domains, using both a manual approach and an artificial intelligence software (BIBOT) that applies natural language processing to automatically identify relevant abstracts. Domains were mapped to core areas, as suggested by the OMERACT 2.1 Filter.

RESULTS

Among the 5,420 references, we included 60 randomized controlled trials, focusing either on overall disease manifestations (53%) or on a single organ/symptom: dry eyes (17%), xerostomia (15%), fatigue (12%), or pulmonary function (3%). The most frequently assessed domains were perceived dryness (52% for overall dryness), fatigue (57%), pain (52%), systemic disease activity (45%), lacrimal gland function (47%) and salivary function (55%), B-cell activation (60%), and health-related quality of life (40%).

CONCLUSION

Our scoping review highlighted the heterogeneity of SjD, in the study designs and domains. This will inform the OMERACT SjD working group to select the most appropriate core domains to be used in SjD clinical trials and to guide the future agenda for outcome measure research in SjD.

Decreased Expression of IL-35 and Its Receptor Contributes to Impaired Megakaryopoiesis in the Pathogenesis of Immune Thrombocytopenia

Recent findings have shown that the level of interleukin-35 (IL-35) is abnormal in several autoimmune diseases. Nonetheless, whether IL-35 participates in the pathogenesis of immune thrombocytopenia (ITP) remains unclear. The current study investigates whether IL-35 modulates megakaryopoiesis. The results show that IL-35 receptors are progressively expressed on bone marrow megakaryocytes during the in vitro differentiation of CD34+ progenitors. IL-35 increases the number of megakaryocyte colony-forming units through the Akt pathway. The level of bone marrow IL-35 is reduced in ITP patients, and the decreased level of IL-35 may inhibit megakaryopoiesis. Then, the potential causes of decreased IL-35 in ITP patients are explored. The primary type of cell that secretes IL-35, known as IL-35-producing regulatory T cells (iTr35), is reduced in ITP patients. Bone marrow mesenchymal stem cells (MSCs) from ITP patients exhibit an impaired capability of inducing iTr35 due to enhanced apoptosis, which may contribute to the reduced level of bone marrow IL-35 in ITP patients. Iguratimod promotes megakaryocyte development and differentiation by elevating the expression of IL-35 receptors on megakaryocytes. Iguratimod improves response rates and reduces bleeding symptoms in corticosteroid-resistant ITP patients.

Efficacy and safety of iguratimod in the treatment of rheumatic and autoimmune diseases: a meta-analysis and systematic review of 84 randomized controlled trials

Objective: To evaluate efficacy and safety of iguratimod (IGU) in the treatment of rheumatic and autoimmune diseases. Methods: Databases such as Pubmed, Embase, Sinomed were searched (as of July 2022) to collect randomized controlled trials (RCTs) of IGU in the treatment of rheumatic and autoimmune diseases. Two researchers independently screened the literature, extracted data, assessed the risk of bias of the included literature, and performed meta-analysis using RevMan 5.4 software. Results: A total of 84 RCTs and 4 types of rheumatic and autoimmune diseases [rheumatoid arthritis (RA), ankylosing spondylitis (AS), primary Sjögren's syndrome (PSS) and Autoimmune disease with interstitial pneumonia]. Forty-three RCTs reported RA and showed that IGU + MTX therapy can improve ACR20 (RR 1.45 [1.14, 1.84], p = 0.003), ACR50 (RR 1.80 [1.43, 2.26], p < 0.0000), ACR70 (RR 1.84 [1.27, 2.67], p = 0.001), DAS28 (WMD -1.11 [-1.69, -0.52], p = 0.0002), reduce ESR (WMD -11.05 [-14.58, -7.51], p < 0.00001), CRP (SMD -1.52 [-2.02, -1.02], p < 0.00001), RF (SMD -1.65 [-2.48, -0.82], p < 0.0001), and have a lower incidence of adverse events (RR 0.84 [0.78, 0.91], p < 0.00001) than the control group. Nine RCTs reported AS and showed that IGU can decrease the BASDAI score (SMD -1.62 [-2.20, -1.05], p < 0.00001), BASFI score (WMD -1.07 [-1.39, -0.75], p < 0.00001), VAS (WMD -2.01 [-2.83, -1.19], p < 0.00001), inflammation levels (decreasing ESR, CRP and TNF-α). Thirty-two RCTs reported PSS and showed that IGU can reduce the ESSPRI score (IGU + other therapy group: WMD -1.71 [-2.44, -0.98], p < 0.00001; IGU only group: WMD -2.10 [-2.40, -1.81], p < 0.00001) and ESSDAI score (IGU + other therapy group: WMD -1.62 [-2.30, -0.94], p < 0.00001; IGU only group: WMD -1.51 [-1.65, -1.37], p < 0.00001), inhibit the inflammation factors (reduce ESR, CRP and RF) and increase Schirmer's test score (IGU + other therapy group: WMD 2.18 [1.76, 2.59], p < 0.00001; IGU only group: WMD 1.55 [0.35, 2.75], p = 0.01); The incidence of adverse events in IGU group was also lower than that in control group (IGU only group: RR 0.66 [0.48, 0.98], p = 0.01). Three RCTs reported Autoimmune disease with interstitial pneumonia and showed that IGU may improve lung function. Conclusion: Based on current evidence, IGU may be a safe and effective therapy for RA, AS, PSS and autoimmune diseases with interstitial pneumonia. Systematic Review Registration: (CRD42021289489).

Effects of iguratimod on inflammatory factors and apoptosis of submandibular gland epithelial cells in NOD mice

Non-obese diabetic (NOD) mice were taken as primary Sjögren's syndrome (pSS) model mice to examine the therapeutic impact of iguratimod (IGU) on inflammatory factors levels and apoptosis of submandibular epithelial cells, and provide experimental basis for the treatment of pSS by iguratimod. Twenty-four NOD murine models were divided into the model, high-dose (IGU 30 mg/kg) and low-dose (IGU 10 mg/kg) groups, eight mice per group. The normal control group comprised eight C57B/L mice. From 8 weeks of age, the NOD mice were administered IGU by intragastric gavage administration every day for 8 weeks; their water consumption, saliva secretion, submandibular gland, and spleen indices were measured. The levels of serum inflammatory factor (IL-1β, TNF-α, IL-6, and IL-17) were evaluated, and Bax, caspase-3, and Bcl-2 levels were detected. The histological alterations in the submandibular glands were discovered. IGU can reduce the water intake of NOD mice (p < 0.01), increase the saliva secretion and the submandibular gland index (p < 0.01); reduce the spleen index and the serum inflammatory factors (p < 0.01); improve the pathological tissue damage and cell apoptosis of the submandibular gland (p < 0.05). IGU can reduce the expression levels of inflammatory mediators in the serum and the extent of lymphocyte infiltration and apoptosis in submandibular gland epithelial cells. It can also regulate apoptosis-related protein expression, thereby improving the secretory function of exocrine glands.

Iguratimod suppresses Tfh cell differentiation in primary Sjögren's syndrome patients through inhibiting Akt/mTOR/STAT3 signaling

BACKGROUND

Iguratimod (IGU) reduces hypergammaglobulinemia and disease activity in pSS (primary Sjögren's syndrome) patients. However, the therapeutical mechanism of IGU for pSS remains largely unknown. This study aimed to investigate the regulation of Tfh cell differentiation by IGU in pSS patients.

METHODS

We prospectively enrolled 13 pSS patients treated with IGU for 3 months and examined circulating T cell and B cell subsets by flow cytometry. We measured Tfh cell differentiation treated by IGU in pSS patients and healthy controls. Transcriptome analysis combined with molecular docking were employed to identify potential therapeutical targets of IGU, which were verified by Western blot and Tfh cell differentiation.

RESULTS

Tfh, plasmablast, and plasma cells were suppressed by IGU treatment at 1 and 3 months. Tfh cell differentiation and function were significant inhibited by IGU in pSS patients and healthy controls in vitro. Pyruvate dehydrogenase kinase 1 (PDK1) was identified as a target of IGU during Tfh cell differentiation, and the downstream Akt phosphorylation was attenuated by IGU. Moreover, the activity of mTORC1 and phosphorylation of STAT3 were suppressed by IGU, with downregulation of BCL6 and upregulation of PRDM1. Finally, Akt activator restored IGU-suppressed Tfh cell differentiation.

CONCLUSIONS

IGU suppresses Tfh cell differentiation in pSS patients through interacting with PDK1 and suppressing Akt-mTOR-STAT3 signaling.

Systematic review with meta-analysis: Efficacy and safety of biological treatment on salivary gland function in primary Sjögren's syndrome

Objective: The study aimed to assess the efficacy and safety of clinical trials of biologics in improving the salivary gland (SG) function in primary Sjögren's syndrome (pSS), which has not been analyzed critically and systematically. Methods: PubMed, Web of Science, ClinicalTrials.gov, the EU Clinical Trials Register, and the Cochrane Library were searched for clinical trials that reported effects of biological treatment on the SG function and safety in pSS patients. Inclusion criteria were defined following participants, interventions, comparisons, outcome, and study design (PICOS) recommendations. The objective index (the change of unstimulated whole saliva (UWS) flow) and the serious adverse event (SAE) were assessed as main outcome measures. A meta-analysis of the efficacy and safety of the treatment was conducted. Quality assessment, sensitivity analysis, and publication bias were assessed. The effect size together with a 95% confidence interval was used to estimate the efficacy and safety of biological treatment and was plotted as a forest plot. Results: The literature search yielded 6,678 studies, nine of which fulfilled the inclusion criteria, with seven randomized controlled trials (RCTs) and two non-RCT clinical studies. Generally, biologics do not significantly increase UWS from the baseline of pSS patients compared to the control group at a matched time point (p = 0.55; standard mean difference, SMD = 0.05; 95% confidence interval, CI: -0.11 and 0.21). However, pSS patients with shorter disease duration (≤3 years; SMD = 0.46; 95% CI: 0.06 and 0.85) were prone to have a better response to biological treatment by showing higher increased UWS than patients with longer disease duration (> 3 years; SMD = -0.03; 95% CI: -0.21 and 0.15) (p = 0.03). For the meta-analysis of the safety of biological treatment, the SAEs in the biologics group were significantly higher than those of the control group (p = 0.0021; log odds ratio, OR = 1.03; 95% CI: 0.37 and 1.69). Conclusion: Biological intervention during the early course of the disease may benefit pSS patients better than that during the late course. Significantly, more SAEs in the biologics group indicate that the safety of biologics needs to be addressed for future biological clinical trials and treatment.

Current and future treatment in primary Sjögren's syndrome - A still challenging development

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease characterized by sicca symptoms, systemic manifestations and constitutional symptoms substantially diminishing patient's quality of life. In this review, we summarize recent recommendations for management of pSS patients and current clinical studies in pSS addressing unmet medical needs. Expanding knowledge about disease pathogenesis and the introduction of validated outcome measures, such as capturing disease activity (ESSDAI) and patient-reported outcomes (ESSPRI) have shaped recent developments. In contrast, lack of evidence for current treatment options remarkably limits the management of pSS patients as reflected by the 2019 updated EULAR recommendations for management of Sjögren's syndrome. In this context, symptomatic treatment is usually appropriate for sicca symptoms, whereas systemic treatment is reserved for moderate to severe organ manifestations including care by a multidisciplinary team in centers of expertise. Most promising targets for new treatment modalities are based on immunopathological insights and include direct B cell targeting strategies, targeting co-stimulation by CD40/CD40L blocking, inhibition of key cytokine activity (BLyS/BAFF, type I interferon) and intracellular signaling pathways.

Composition and regulation of the immune microenvironment of salivary gland in Sjögren’s syndrome

Primary Sjögren’s syndrome (pSS) is a systemic autoimmune disease characterized by exocrine gland dysfunction and inflammation. Patients often have dry mouth and dry eye symptoms, which seriously affect their lives. Improving dry mouth and eye symptoms has become a common demand from patients. For this reason, researchers have conducted many studies on external secretory glands. In this paper, we summarize recent studies on the salivary glands of pSS patients from the perspective of the immune microenvironment. These studies showed that hypoxia, senescence, and chronic inflammation are the essential characteristics of the salivary gland immune microenvironment. In the SG of pSS, genes related to lymphocyte chemotaxis, antigen presentation, and lymphocyte activation are upregulated. Interferon (IFN)-related genes, DNA methylation, sRNA downregulation, and mitochondrial-related differentially expressed genes are also involved in forming the immune microenvironment of pSS, while multiple signaling pathways are involved in regulation. We further elucidated the regulation of the salivary gland immune microenvironment in pSS and relevant, targeted treatments.

A Systematic Review and Meta-Analysis of 19 Randomized Controlled Trials of Iguratimod Combined With Other Therapies for Sjogren’s Syndrome

Objective

To explore the efficacy and safety of Iguratimod intervention in Primary Sjogren’s syndrome (pSS).

Methods

Many databases were searched to collect the RCTs. Three independent reviewers extracted data and assessed the quality of the studies based on the Cochrane Handbook. The statistical analysis was done by RevMan 5.3 and STATA. The quality of evidence was evaluated by GRADE tool.

Results

Twenty-nine RCTs with 2258 participants were included in this review. The meta-analysis shows that: iguratimod experiment group can reduce the ESSPRI score (WMD -1.93 [-2.33, -1.52], P&lt;0.00001), ESSDAI score (WMD -1.39 [-1.81, -0.98], P&lt;0.00001), Schirmer’s test (WMD 1.77 [0.85, 2.70], P=0.0002), RF (WMD -5.78 [-7.59, -3.97], P&lt;0.00001), and decrease the ESR level (WMD -7.05 [-9.84, -4.26], P&lt;0.00001). Meanwhile, the summary result showed the addiction of Iguratimod may not increase the adverse events. The adverse events were mainly gastrointestinal discomfort, abnormal liver function, and rash and itching. The quality of evidence of adverse events was moderate. Referring to minimal clinically important difference (MCID), the improvement of ESSPRI is clinically significant, and the improvement of ESSDAI for patients older than 60 years old may be clinically significant.

Conclusion

Based on current evidence, iguratimod can effectively reduce ESSPRI score, ESSDAI score, Schirmer’s test score and decrease systemic inflammatory response (such as ESR level and RF level) without increasing the probability of adverse events. The recommended course of treatment is at least 12 weeks.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?, identifier CRD42020220770.

Efficacy and Safety of Iguratimod Supplement to the Standard Immunosuppressive Regimen in Highly Mismatched Renal Transplant Recipients: A Pilot Study

Iguratimod (IGU) can mitigate the symptoms of rheumatoid arthritis through its anti-inflammatory effects. The objective of this study was to investigate the clinical efficacy and safety of IGU in highly HLA-mismatched renal transplant recipients, in combination with standard immunosuppressive regimen. This pilot study was designed as an open-label, blank-control, randomized clinical trial on patients recruited from a single transplant center in China. Patients who met the inclusion criteria were randomized to the IGU (n=27) and blank control (n=27) groups. IGU was administrated with the conventional triple immunosuppressive protocol for 52 weeks after kidney transplantation. The incidence of biopsy-proven acute rejection rate was 14.8% (4/27) in the IGU group and 29.6% (8/27) in the control group, P = 0.19. The clinical rejection rate was also substantially reduced in the IGU group (3.7% vs. 18.5%, P = 0.08). De novo donor-specific antibody also showed a decline trend in the IGU group after 52 weeks. The graft function and incidence of adverse events were similar between the two groups. In addition, IGU intervention significantly decreased the number of NK cells throughout the follow-up. In conclusion, our study has shown the possibility that IGU could reduce the allograft rejection rate and de novo DSA with appreciable safety in combination with conventional immunosuppressants. Formal clinical trials were warranted based on current findings.

An update of targeted therapeutic options for primary Sjögren syndrome: current status and future development

Introduction: Primary Sjögren syndrome (pSS) is a systemic autoimmune disease that may affect 3 in 1,000 people within the general population. The therapeutic scenario is complex, and no therapy has proved to be able to modify the natural course of the disease, nor to prevent the most severe systemic complications.Areas covered: Recently, the EULAR 2020 Recommendations for pSS have underlined the low level of evidence supporting efficacious therapeutic approaches, lacking a definition of specific treatment targets and being far from the 'disease modification' concept that is frequently used in other diseases. Herein, the authors review the status of current targeted therapies and provide the reader with their expert opinion.Expert opinion: The progress in discovering novel treatments for pSS seem to be focused on searching new biological therapies as highly-selective drugs that can be effective without the adverse effects related to the wide, nonspecific immunosuppression induced by the drugs currently used. Most likely, the more disruptive therapeutic approach in pSS that could be seen in a few years is the use of combination strategies targeting different etiopathogenic pathways.

Effectiveness and Safety of Iguratimod in Treating Primary Sjögren's Syndrome: A Systematic Review and Meta-Analysis

Objectives: We aimed to assess the effectiveness and safety of iguratimod (IGU) in treating primary Sjögren’s syndrome (pSS) by meta-analysis.

Methods: Eight databases and two clinical trial websites were searched from conception to August 10, 2020, for relevant randomized controlled trials (RCTs) on outcomes of patients with pSS treated with IGU. Revman 5.4 was used for statistical analysis and creating plots.

Results: A total of 1,384 patients with pSS from 19 RCTs were included in this meta-analysis. Pooled results demonstrated that patients treated with IGU + hydroxychloroquine (HCQ) + glucocorticoid (GC) showed significant differences in erythrocyte sedimentation rate (ESR), rheumatoid factor (RF) level, platelet (PLT) count, immunoglobulin G (IgG) level, salivary flow rate, Schirmer’s test result, EULAR Sjögren’s Syndrome Patient Reported Index (ESSPRI), EULAR Sjögren’s Syndrome Disease Activity Index (ESSDAI), and efficacy rate (p ≤ 0.01) compared to patients treated with HCQ + GC. Compared to treatment with HCQ and GC, co-administration of IGU with GC showed significant differences in ESR and RF level (p ≤ 0.01); however, no significant differences were noted in IgG level. Conversely, the IgG level showed a significant improvement in the IGU + HCQ + GC group compared to the HCQ + GC group. The results of safety analysis revealed that seven trials showed no significant differences in adverse events (AEs) between the IGU + HCQ + GC and HCQ + GC groups (p = 0.15). Although no severe AEs were noted, gastrointestinal discomfort was the most common AE in the IGU group. No significant differences in AEs were observed between the IGU + GC and HCQ + GC groups.

Conclusion: IGU improved the clinical symptoms of patients with pSS, including inflammatory indicators (ESR, IgG, and RF levels), PLT count, secretion function of the salivary and lacrimal glands (salivary flow rate and Schirmer’s test result), and disease indexes (ESSDAI and ESSPRI), when co-administered with HCQ + GC therapy without increasing the risks of AEs. Therefore, IGU can be considered as an effective and safe drug for clinical therapy of pSS. Considering the limitations of the present trials, more long-term, multicenter, and high-quality RCTs are required to assess the effectiveness and safety of IGU for treating patients with pSS.

Immune Monitoring upon Treatment with Biologics in Sjögren's Syndrome: The What, Where, When, and How

Over the years, a wide variety of therapeutic antibodies has been successfully introduced in the auto-immunology clinic, and many more are on the way. Many of these treatments address either a pathogenic circulating molecule or a cell-bound molecule. Whereas addressing the former target results in neutralization of the soluble factor and binding to the latter target either inhibits cellular function or induces selective cell death. If this targeted molecule or cell is part of the immune system, this therapy evokes a state of immunodeficiency with infections as a possible consequence. Therefore, immune monitoring is needed to prevent such adverse side effects of immunotherapy. In this paper, different immunotherapies used in Sjögren's syndrome, as well as different approaches to monitoring the immune system, are discussed.