Serum Cytokines Th1, Th2, and Th17 Expression Profiling in Active Lupus Nephritis-IV: From a Southern Chinese Han Population

Sequential administration of paricalcitol followed by IL-17 blockade for progressive refractory IgA nephropathy patients

There is no established treatment for progressive IgA nephropathy refractory to steroids and immunosuppressant drugs (r-IgAN). Interleukin 17 (IL-17) blockade has garnered interest in immune-mediated diseases involving the gut-kidney axis. However, single IL-17A inhibition induced paradoxical effects in patients with Crohn's disease and some cases of de novo glomerulonephritis, possibly due to the complete Th1 cell response, along with the concomitant downregulation of regulatory T cells (Tregs). Seven r-IgAN patients were treated with at least six months of oral paricalcitol, followed by the addition of subcutaneous anti-IL-17A (secukinumab). After a mean follow-up of 28 months, proteinuria decreased by 71% (95% CI: 56-87), P < 0.001. One patient started dialysis, while the annual eGFR decline in the remaining patients [mean (95% CI)] was reduced by 4.9 mL/min/1.73 m2 (95% CI: 0.1-9.7), P = 0.046. Circulating Th1, Th17, and Treg cells remained stable, but Th2 cells decreased, modifying the Th1/Th2 ratio. Intriguingly, accumulation of circulating Th17.1 cells was observed. This novel sequential therapy appears to optimize renal advantages in patients with r-IgAN and elicit alterations in potentially pathogenic T helper cells.

Latent Tuberculosis Infection and Associated Factors in Patients with Systemic Lupus Erythematosus: a Multicenter, Cross-Sectional Study

The objectives of this study were to screen for latent tuberculosis infection (LTBI) among patients with systemic lupus erythematosus (SLE) using the T-SPOT.TB assay and to identify factors affecting the assay results. SLE patients were enrolled from 13 tertiary hospitals in eastern, central, and western China from September 2014 to March 2016 and were screened using the T-SPOT.TB assay to detect LTBI. Basic information about the subjects was collected, including gender, age, body mass index (BMI), course of disease, evidence of previous tuberculosis, Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score, and the use of glucocorticoids and immunosuppressants. Univariate analysis and multivariable logistic regression were performed to identify factors affecting the results of the T-SPOT.TB assay. In all, 2,229 SLE patients were screened using the T-SPOT.TB assay, of whom 334 patients tested positive, yielding a positivity rate of 15% (95% confidence interval [CI], 13.5% to 16.5%). The positivity rate was higher in male than female patients and had an increasing trend with age. Multivariable logistic regression analysis showed that patients over 40 (odds ratio [OR], 1.65; 95% CI, 1.29 to 2.10) and with evidence of previous tuberculosis (OR, 4.43; 95% CI, 2.81 to 6.99) were more likely to have positive T-SPOT.TB results, while patients with a SLEDAI-2K score of ≥10 (OR, 0.61; 95% CI, 0.43 to 0.88), a glucocorticoid dose of ≥60 mg/d (OR, 0.62; 95% CI, 0.39 to 0.98), leflunomide (LEF) treatment (OR, 0.51; 95% CI, 0.29 to 0.88), or tacrolimus (FK506) treatment (OR, 0.40; 95% CI, 0.16 to 1.00) were more likely to have negative T-SPOT.TB results. The frequencies of CFP-10-specific gamma interferon (IFN-γ)-secreting T cells were significantly lower in SLE patients with severe disease activity or high-dose glucocorticoids (P < 0.05). The positivity rate of the T-SPOT.TB assay was 15% among SLE patients. Severe, active SLE disease and the use of high-dose glucocorticoids and some types of immunosuppressants are likely to result in negative T-SPOT.TB results. For SLE patients with the above conditions, diagnosing LTBI based on a positive T-SPOT.TB result may lead to underestimation of the prevalence. IMPORTANCE The burden of tuberculosis and systemic lupus erythematosus in China ranks among the top three in the world. Therefore, active screening for LTBI and preventive intervention in SLE patients are of great significance in China. In view of the lack of relevant data in a large sample, we conducted a multicenter, cross-sectional study using T-SPOT.TB as a screening method for LTBI, to investigate the prevalence of LTBI and analyze the factors affecting the results of the T-SPOT.TB assay in SLE patients. Our study showed that the overall positivity rate of the T-SPOT.TB assay in SLE patients was 15.0%, which was lower than the estimated LTBI prevalence in the general population in China (~20%). For SLE patients with severe, active disease, high-dose glucocorticoids, and some types of immunosuppressants, a diagnosis of LTBI based on only positive T-SPOT.TB results may lead to underestimation of the prevalence.

Imbalance of helper T cell type 1, helper T cell type 2 and associated cytokines in patients with systemic lupus erythematosus: A meta-analysis

Objective: Th1 and Th2 cells and their associated cytokines function in the pathogenesis of systemic lupus erythematosus (SLE), but their exact roles are uncertain. We performed a meta-analysis to examine the relationship of these cells and cytokines with SLE.

Methods: Multiple databases were searched to identify publications that reported the percentages of Th1 and Th2 cells and their associated cytokines in SLE patients and healthy controls (HCs). Meta-analysis was performed using Stata MP version 16.

Results: SLE patients had a lower percentage of Th1 cells, a higher percentage of Th2 cells, and higher levels of Th1- and Th2-associated cytokines than HCs. SLE treatments normalized some but not all of these indicators. For studies in which the proportion of females was less than 94%, the percentage of Th2 cells and the level of IL-10 were higher in patients than HCs. SLE patients who had abnormal kidney function and were younger than 30 years old had a higher proportion of Th1 cells than HCs. SLE patients more than 30 years old had a higher level of IL-6 than HCs.

Conclusion: Medications appeared to restore the balance of Th1 cells and other disease indicators in patients with SLE. Gender and age affected the levels of Th1 and Th2 cells, and the abnormally elevated levels of Th2 cells appear to be more pronounced in older patients and males.

Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42022296540].

IL-38, a potential therapeutic agent for lupus, inhibits lupus progression

BACKGROUND

Previous studies reported that IL-38 was abnormally expressed in patients with systemic lupus erythematosus (SLE). However, the involvement of IL-38 in the pathophysiology of SLE remains unknown.

METHODS

The therapeutic potential of IL-38 was tested in pristane-treated wild-type (WT) and IL-38^-/- mice. Thus, SLE was induced via pristane in WT and IL-38^-/- mice. Afterwards, the liver, spleen, and kidney of each mouse were obtained. The flow cytometric analysis of the immune cells, serologic expression of inflammatory cytokines and autoantibodies, renal histopathology, and inflammatory signaling were evaluated.

RESULTS

WT mice with pristane-induced lupus exhibited hepatomegaly, splenomegaly, severe kidney damages, increased lymphoproliferation, enhanced lymphoproliferation, and upregulated inflammatory cytokines, such as IL-6, IL-13, IL-17A, MIP-3α, IL-12p70, and IFNγ, and elevated levels of autoantibodies, such as ANA IgG, anti-dsDNA IgG, and total IgG. IL-38^-/- mice whose lupus progressed, had elevated cells of CD14⁺, CD19⁺, CD3⁺, and Th1, upregulated inflammatory cytokines and autoantibodies, and severe pathological changes in kidney. Administration of recombinant murine IL-38 to pristane-treated IL-38^-/- mice improved their renal histopathology, which depended on ERK1/2, JNK1/2, p38, NF-κB p65, and STAT5 signaling pathways.

CONCLUSION

IL-38 regulates SLE pathogenesis. Furthermore, targeting IL-38 is critical in the treatment of SLE.

Longitudinal comparison of IL-6, IL-10, and IL-12 cytokine profiles in adult and childhood-onset systemic lupus erythematosus

Objective

To compare the levels of Th1 (IL-12) and Th2 (IL-6 and IL10) cytokines over a two-year period among systemic lupus erythematosus patients with childhood-onset (cSLE), adult-onset (sSLE), and healthy controls, and correlate with their clinical, laboratory, and treatment manifestations.

Methods

The study included 63 patients with cSLE [57 (90%) women; mean age 19.7 ± 4.3 years (range = 10-29); mean disease duration 7.3 ± 4.2 years (range 2-15)], 67 patients with aSLE [65 (97%) women; mean age of 39.9 ± 11.8 years (range 21-68); disease duration 7.7 ± 3.1 years (range 4-16)], and 40 healthy controls [36 (90%) women; mean age of 29.6 ± 10 years (range 12-49)]. cSLE and aSLE patients were paired by disease duration. Clinical and laboratory manifestations, disease activity (SLEDAI), cumulative damage (SDI), and current drug exposures were evaluated. Symptoms of anxiety and depression were evaluated by the Beck inventory (BAI and BDI, respectively). Th1 (IL-12) and Th2 (IL-6 and IL-10) cytokines were measured by the ELISA test. Data were collected at four different time points (TI, TII, TIII, and TIV) and compared by non-parametric tests.

Results

IL-6 levels were significantly higher in aSLE patients compared to healthy controls at times I, II, and III (TI p = 0.013, TII p = 0.015, TIII p = 0.004, and TIV p = 0.634). However, no difference was observed between cSLE patients and healthy controls (TI p = 0.223, TII p = 0.613, TIII p = 0.341, and TIV p = 0.977). In addition, no difference was observed between aSLE and cSLE patients (TI p = 0.377, TII p = 0.123, TIII p = 0.105, and TIV p = 0.591). The levels of IL-12 were significantly higher in cSLE patients compared to healthy controls at all time points (TI p = 0.04, TII p < 0.001, TIII p = 0.015, and TIV p = 0.021). aSLE patients showed significantly elevated levels when compared to healthy controls at time III and IV (TI p = 0.752, TII p = 0.827, TIII p = 0.011*, and TIV p < 0.001*). cSLE patients showed significantly higher levels than aSLE patients at times I and II (TI p = 0.07*, TII p < 0.001*, TIII p = 0.998, and TIV p = 0.140). In aSLE patients, IL-6 was associated with headache (p = 0.006), arthritis (p = 0.044), and nephritis (p = 0.012); IL-10 was associated with nephritis (p = 0.043), hypocomplementemia (p = 0.001), and disease activity (p = 0.001); in these patients, IL-12 was associated with alopecia (p = 0.025) and leukopenia (p = 0.044). In cSLE patients, IL-6 was associated with arthritis (p = 0.022) and malar rash (p = 0.012).

Conclusion

aSLE and cSLE patients with long disease duration present similar levels of cytokines, despite differences in clinical activity patterns over time.

Pathogenic T-Cell Responses in Immune-Mediated Glomerulonephritis

Glomerulonephritis (GN) comprises a group of immune-mediated kidney diseases affecting glomeruli and the tubulointerstitium. Glomerular crescent formation is a histopathological characteristic of severe forms of GN, also referred to as crescentic GN (cGN). Based on histological findings, cGN includes anti-neutrophil cytoplasmic antibody (ANCA)-associated GN, a severe form of ANCA-associated vasculitis, lupus nephritis associated with systemic lupus erythematosus, Goodpasture’s disease, and IgA nephropathy. The immunopathogenesis of cGN is associated with activation of CD4+ and CD8+ T cells, which particularly accumulate in the periglomerular and tubulointerstitial space but also infiltrate glomeruli. Clinical observations and functional studies in pre-clinical animal models provide evidence for a pathogenic role of Th1 and Th17 cell-mediated immune responses in cGN. Emerging evidence further argues that CD8+ T cells have a role in disease pathology and the mechanisms of activation and function of recently identified tissue-resident CD4+ and CD8+ T cells in cGN are currently under investigation. This review summarizes the mechanisms of pathogenic T-cell responses leading to glomerular damage and renal inflammation in cGN. Advanced knowledge of the underlying immune mechanisms involved with cGN will enable the identification of novel therapeutic targets for the replacement or reduction in standard immunosuppressive therapy or the treatment of refractory disease.

Immunomodulatory Activity of Mesenchymal Stem Cells in Lupus Nephritis: Advances and Applications

Lupus nephritis (LN) is a significant cause of various acute and chronic renal diseases, which can eventually lead to end-stage renal disease. The pathogenic mechanisms of LN are characterized by abnormal activation of the immune responses, increased cytokine production, and dysregulation of inflammatory signaling pathways. LN treatment is an important issue in the prevention and treatment of systemic lupus erythematosus. Mesenchymal stem cells (MSCs) have the advantages of immunomodulation, anti-inflammation, and anti-proliferation. These unique properties make MSCs a strong candidate for cell therapy of autoimmune diseases. MSCs can suppress the proliferation of innate and adaptive immune cells, such as natural killer cells (NKs), dendritic cells (DCs), T cells, and B cells. Furthermore, MSCs suppress the functions of various immune cells, such as the cytotoxicity of T cells and NKs, maturation and antibody secretion of B cells, maturation and antigen presentation of DCs, and inhibition of cytokine secretion, such as interleukins (ILs), tumor necrosis factor (TNF), and interferons (IFNs) by a variety of immune cells. MSCs can exert immunomodulatory effects in LN through these immune functions to suppress autoimmunity, improve renal pathology, and restore kidney function in lupus mice and LN patients. Herein, we review the role of immune cells and cytokines in the pathogenesis of LN and the mechanisms involved, as well as the progress of research on the immunomodulatory role of MSCs in LN.

Involvement of Inflammasome Components in Kidney Disease

Inflammasomes are multiprotein complexes with an important role in the innate immune response. Canonical activation of inflammasomes results in caspase-1 activation and maturation of cytokines interleukin-1β and -18. These cytokines can elicit their effects through receptor activation, both locally within a certain tissue and systemically. Animal models of kidney diseases have shown inflammasome involvement in inflammation, pyroptosis and fibrosis. In particular, the inflammasome component nucleotide-binding domain-like receptor family pyrin domain containing 3 (NLRP3) and related canonical mechanisms have been investigated. However, it has become increasingly clear that other inflammasome components are also of importance in kidney disease. Moreover, it is becoming obvious that the range of molecular interaction partners of inflammasome components in kidney diseases is wide. This review provides insights into these current areas of research, with special emphasis on the interaction of inflammasome components and redox signalling, endoplasmic reticulum stress, and mitochondrial function. We present our findings separately for acute kidney injury and chronic kidney disease. As we strictly divided the results into preclinical and clinical data, this review enables comparison of results from those complementary research specialities. However, it also reveals that knowledge gaps exist, especially in clinical acute kidney injury inflammasome research. Furthermore, patient comorbidities and treatments seem important drivers of inflammasome component alterations in human kidney disease.

The Th17/IL-17 Axis and Kidney Diseases, With Focus on Lupus Nephritis

Systemic lupus erythematosus (SLE) is a disease characterized by dysregulation and hyperreactivity of the immune response at various levels, including hyperactivation of effector cell subtypes, autoantibodies production, immune complex formation, and deposition in tissues. The consequences of hyperreactivity to the self are systemic and local inflammation and tissue damage in multiple organs. Lupus nephritis (LN) is one of the most worrying manifestations of SLE, and most patients have this involvement at some point in the course of the disease. Among the effector cells involved, the Th17, a subtype of T helper cells (CD4+), has shown significant hyperactivation and participates in kidney damage and many other organs. Th17 cells have IL-17A and IL-17F as main cytokines with receptors expressed in most renal cells, being involved in the activation of many proinflammatory and profibrotic pathways. The Th17/IL-17 axis promotes and maintains repetitive tissue damage and maladaptive repair; leading to fibrosis, loss of organ architecture and function. In the podocytes, the Th17/IL-17 axis effects include changes of the cytoskeleton with increased motility, decreased expression of health proteins, increased oxidative stress, and activation of the inflammasome and caspases resulting in podocytes apoptosis. In renal tubular epithelial cells, the Th17/IL-17 axis promotes the activation of profibrotic pathways such as increased TGF-β expression and epithelial-mesenchymal transition (EMT) with consequent increase of extracellular matrix proteins. In addition, the IL-17 promotes a proinflammatory environment by stimulating the synthesis of inflammatory cytokines by intrinsic renal cells and immune cells, and the synthesis of growth factors and chemokines, which together result in granulopoiesis/myelopoiesis, and further recruitment of immune cells to the kidney. The purpose of this work is to present the prognostic and immunopathologic role of the Th17/IL-17 axis in Kidney diseases, with a special focus on LN, including its exploration as a potential immunotherapeutic target in this complication.

Immunopathological analysis of the expression of glomerular exostosin 1 and exostosin 2 in Japanese patients with lupus nephritis

Exostosin 1 and exostosin 2 (EXT1/EXT2) on glomerular basement membrane (GBM) were recently reported as novel putative antigens in secondary membranous nephropathy with autoimmune disease. However, the clinical significance of glomerular EXT1/EXT2 remains elusive in patients with lupus nephritis (LN). The immunofluorescence staining pattern of glomerular EXT1/EXT2 is also undetermined in membranous LN (MLN) or proliferative LN (PLN). We cross-sectionally analyzed patients with MLN (pure class V, n = 11) and PLN (class III, IV, and mixed class III/IV + V, n = 22) who underwent renal biopsies between 2010 and 2020 at Showa University Hospital. Glomerular EXT1/EXT2 expressions were evaluated by immunofluorescence. T-helper (Th) cell-related serum inflammatory cytokines were measured using enzyme-linked immunosorbent assay. The positivity for both EXT1/EXT2 was higher in patients with MLN than PLN (90.9% vs 63.6%, P = 0.212). MLN showed global and bright granular EXT1/EXT2 expressions along GBM, while PLN showed segmental and moderate expressions on GBM. Additionally, glomerular EXT1/EXT2 positivity was not associated with the degree of proteinuria or renal function in MLN and PLN patients, but the levels of serum anti-dsDNA antibody and circulating immune complexes were lower in patients with EXT1/EXT2-positive MLN than EXT1/EXT2-negative PLN. Moreover, serum complement levels and IL-4/IFN-γ ratios were elevated in EXT1/EXT2-positive MLN than EXT1/EXT2-negative PLN. Collectively, immunofluorescence staining for glomerular EXT1/EXT2 had characteristic patterns between MLN and PLN. Glomerular EXT1/EXT2 expressions tended to be high in Th2-dominant MLN patients without severe hypocomplementemia and elevated autoantibodies. Thus, EXT1/EXT2 might be involved in the unique developmental mechanism of MLN.

Rapamycin alleviates renal damage in mice with systemic lupus erythematosus through improving immune response and function

This study aimed to explore the therapeutic effect and mechanism of rapamycin (RAPA) on systemic lupus erythematosus (SLE) in BALB/C mice induced by pristane. The mice were randomly divided into 5 groups (n = 6): control, model, saline, RAPA (1 mg/kg) and RAPA (2 mg/kg). All groups were injected with pristane except control. HE staining revealed 1 mg/kg and 2 mg/kg RAPA treatments obviously alleviated pathological changes in the kidney of SLE mice such as glomeruli enlargement, hyperplasia of mesangial cells, epithelial and endothelial cells, infiltration of inflammatory cells, and edema-like degeneration of renal tubules. Compared with control group, body weights and anti-ribosomal P-protein antibody (ARPA) level of the mice in model group and saline group decreased (P < 0.05), while immune complex deposition and levels of anti-dsDNA antibody, anti-smRNP antibody and urine protein in model group and saline group increased (P < 0.05). However, compared with model group and saline group, body weights of the mice in RAPA (1 mg/kg) group and RAPA (2 mg/kg) group increased (P < 0.05), while immune complex deposition and levels of anti-dsDNA antibody, anti-smRNP antibody, ARPA, and urine protein in RAPA (1 mg/kg) group and RAPA (2 mg/kg) group decreased (P < 0.05). Compared with control group, the proportion of dentritic cells (DC) in the kidney and peripheral blood decreased while the proportion of Th1, Th2 and Th17 cells in the spleen, kidney and peripheral blood increased in model group and saline group (P < 0.05). Compared with model group and saline group, 1 mg/kg and 2 mg/kg RAPA treatments boosted the proportion of DC in the kidney and peripheral blood, reduced the proportion of Th1 and Th17 cells in the spleen, kidney and peripheral blood, and lessened the proportion of Th2 cells in the kidney and peripheral blood (P < 0.05). In conclusion, RAPA alleviated renal damage in SLE mice through improving immune response and function.

Salivary Cytokines as Potential Diagnostic Biomarkers for Systemic Lupus Erythematosus Disease

Systemic lupus erythematosus (SLE) is a complex autoimmune inflammatory disease characterized by an unknown etiology and a highly variable clinical presentation. This clinical heterogeneity might be explained by dysregulation of tolerance to self and apoptotic mechanisms, overproduction of autoantibodies, and abnormal cytokine levels. Cytokine imbalance levels have been associated with disease activity and severity in SLE patients. In the last years, salivary cytokines related to SLE have gained significant attention and researchers have begun to focus on the identification of cytokines in the saliva of SLE patients using it as a diagnostic fluid for the inflammatory process underlying SLE. This review highlights and summarizes recent studies revealing the cytokines that have been identified in the saliva of individuals with SLE. Data reported and discussed in this report may provide useful additional information to better understand the mechanisms associated with the disease.

Correlation between circulating interleukin-18 level and systemic lupus erythematosus: a meta-analysis

This study is a meta-analysis aimed at pooling reported data and clarifying the association between circulating level of interleukin-18 and systemic lupus erythematosus (SLE). We searched medical databases including Medline/Pubmed, Embase, Scopus, The Cochrane Library, and Web of Science thoroughly to obtain all related articles published before July 15th, 2020. We pooled computed standardized mean difference (SMD) and its 95% confidence interval using STATA 13.0 and exhibited in the form of forest graph. Meta-regression and subgroup analysis were also performed to explore the source of heterogeneity. Publication bias was first evaluated by the symmetry of the funnel plot and then Egger’s linear regression test. Thirty eligible studies from eighteen regions were finally included and the relevant data from these studies were pooled. The analysis results displayed that SLE patients showed a significantly higher level of circulating IL-18 level in comparison with healthy controls (SMD = 1.56, 95% CI [1.20–1.93]; I² = 94.9%, p < 0.01). The conclusion was equally applicable in subgroups divided based on sample type, mean age, disease duration, and testing method. Patients with SLEDAI score higher than five, or who were Asian, White, Arab, or mixed ethnicity had an elevated level of IL-18, while the others didn’t. This meta-analysis has elucidated that compared with healthy people, the circulating level of IL-18 is considerably higher in SLE patients, which indicates the underlying role of IL-18 in SLE pathogenesis.

Bach2 overexpression represses Th9 cell differentiation by suppressing IRF4 expression in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by abnormal activation of T cells and caused by an imbalance in the production and clearance of apoptotic cells. We previously showed that the transcription regulator Bach2 regulated abnormal B‐cell activation in SLE. Here, we investigated whether Bach2 was also involved in Th9 cell differentiation in SLE. We found that the proportion of Th9 cells was enhanced in the peripheral blood mononuclear cells (PBMC) of SLE patients. The PBMC and CD4⁺ T cells of SLE patients exhibited a decrease of Bach2 expression and an increase of IL‐9 expression. Furthermore, Bach2 overexpression significantly repressed the levels of PU.1, IRF4, IL‐9, and Th9 cells in the CD4⁺ T cells of SLE patients and healthy volunteers. In addition, Bach2 overexpression inhibited the levels of IL‐9 and Th9 cells, whereas IRF4 upregulation enhanced the levels of IRF4 and IL‐9 and Th9 cells in the CD4⁺ T cells of SLE patients and healthy volunteers. The effect of IRF4 up‐regulation was abolished by Bach2 overexpression. In summary, our work suggests that Bach2 overexpression represses Th9 cell differentiation by suppressing IRF4 expression in SLE, and thus, Bach2 may be a novel potential target for SLE treatment.

Activity Disease in SLE Patients Affected IFN-γ in the IGRA Results

PURPOSE

Highly active systemic lupus erythematosus (SLE) causes a high risk of tuberculosis (TB) infection in SLE patients in Indonesia, a country in which the disease, especially extrapulmonary TB, is endemic. Interferon (IFN)-γ releasing assay (IGRA) can detect latent or previous TB infection. This study sought to determine latent TB infection and levels of IFN-γ, a key player in various inflammation and autoimmune disease, in patients with SLE and relate findings to disease activity.

PATIENTS AND METHODS

This experimental study included 79 female subjects distributed into three groups of active SLE, quiescent SLE and healthy controls. We used SLE Disease Activity Index-2000 (SLEDAI-2K) scores to stratify the subjects. Each group underwent IGRA testing using the QuantiFERON-TB Gold Plus kit.

RESULTS

We recruited 59 female patients with SLE. The patients had a median age and disease duration 30 and 5 years, respectively. Statistical analysis using the Kruskal-Wallis test showed that active condition, high SLEDAI-2K score and immunosuppressive therapies affect IGRA results. Specifically, healthy controls (n=20) were most likely to have negative IGRA results (67.09%), whilst 27.27% of active cases (n=33) and 3.85% of quiescent cases (n=26) had indeterminate results (p=0.02). The number of immunosuppressant therapies was significantly negatively correlated with IFN-γ (p=0.004). No difference in IFN-γ concentration was detected amongst the active and other groups (p>0.05).

CONCLUSION

High-activity SLE and immunosuppressive therapies cause dysregulation of the immune response, which, in turn, influences IGRA results. Thus, additional testing is necessary to detect TB infection in patients with SLE.

Th1, Th2, and Th17 cytokines in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the breakdown of immune tolerance leading to excessive inflammation and tissue damage. Imbalance in the levels of cytokines represents one of the multifactorial causes of SLE pathogenesis and it contributes to disease severity. Deregulated levels of T helper type 1 (Th1), type 2 (Th2), and type 17 (Th17) cytokines have been associated with autoimmune inflammation. Growing evidence has shown deregulated levels of Th1, Th2, and Th17 cytokines in SLE patients compared to healthy controls associated with disease activity and severity. In this review, we describe and discuss the levels of Th1, Th2, and Th17 cytokines in SLE patients, and clinical trials involving Th1, Th2, and Th17 cytokines in SLE patients. In particular, with the exception of IL-2, IL-4, and TGF-β1, the levels of Th1, Th2, and Th17 cytokines are increased in SLE patients associated with disease severity. Current phase II or III studies involve therapeutic antibodies targeting IFN-α and type I IFN receptor, while low-dose IL-2 therapy is assessed in phase II clinical trials.

Elevated interleukin-25 and its association to Th2 cytokines in systemic lupus erythematosus with lupus nephritis

Systemic lupus erythematosus (SLE) is an autoimmune disorder that is associated with lupus nephritis, initiated by the deposition of immune complexes in the kidney; subsequently, this induces the overexpression of cytokines. Lupus nephritis is known as one of the major clinical manifestations that affect the disease severity in SLE patients. An increased number of resident periglomerular and immune cells in the kidney has the potential to affect the equilibrium of different immune cell subsets, such as Th1, Th2, Th17, and Tregs, which may be central to the induction of tissue damage in kidney by exerting either proinflammatory or anti-inflammatory effects, or both. This equilibrium has yet to be confirmed, as new players such as IL-25 remain undiscovered. IL-25 is a cytokine of the IL-17 family, which stimulates Th2-mediated immune response when overly expressed. Thus, the aim of this research is to determine the plasma levels of IL-25 and Th2-associated cytokines (IL-4, IL-5, IL-6, IL-9, IL-10, IL-13) in SLE patients with (SLE-LN) and without lupus nephritis. Sixty-four (n = 64) SLE patients and fifteen (n = 15) healthy individuals were recruited. This study demonstrated that the IL-9, IL-10 and IL-25 had significantly increased expressions in SLE-LN, followed by SLE without LN, compared to healthy controls. Meanwhile, IL-5 and IL-6 had significantly reduced. No significant difference was observed with IL-13, while the level of IL-4 was undetectable. Furthermore, IL-9 and IL-10 were significantly correlated with the IL-25, and IL-25, IL-9 and IL-10 were positively correlated with the disease severity score, SLEDAI. In conclusion, IL-25 and its associated Th2 cytokines (IL-9 and IL-10) may be involved in SLE pathogenesis. These cytokines could be potential biomarkers in monitoring and predicting the disease severity during SLE pathogenesis.

Comparative Study of the Molecular Basis of Pathogenicity of M. bovis Strains in a Mouse Model

It is widely accepted that different strains of Mycobacterium tuberculosis have variable degrees of pathogenicity and induce different immune responses in infected hosts. Similarly, different strains of Mycobacterium bovis have been identified but there is a lack of information regarding the degree of pathogenicity of these strains and their ability to provoke host immune responses. Therefore, in the current study, we used a mouse model to evaluate various factors involved in the severity of disease progression and the induction of immune responses by two strains of M. bovis isolated from cattle. Mice were infected with both strains of M. bovis at different colony-forming unit (CFU) via inhalation. Gross and histological findings revealed more severe lesions in the lung and spleen of mice infected with M. bovis N strain than those infected with M. bovis C68004 strain. In addition, high levels of interferon-γ (IFN-γ), interleukin-17 (IL-17), and IL-22 production were observed in the serum samples of mice infected with M. bovis N strain. Comparative genomic analysis showed the existence of 750 single nucleotide polymorphisms and 145 small insertions/deletions between the two strains. After matching with the Virulence Factors Database, mutations were found in 29 genes, which relate to 17 virulence factors. Moreover, we found an increased number of virulent factors in M. bovis N strain as compared to M. bovis C68004 strain. Taken together, our data reveal that variation in the level of pathogenicity is due to the mutation in the virulence factors of M. bovis N strain. Therefore, a better understanding of the mechanisms of mutation in the virulence factors will ultimately contribute to the development of new strategies for the control of M. bovis infection.

Induction therapy downregulates the expression of Th17/Tfh cytokines in patients with active lupus nephritis

To determine the potential changes of IL-6, IL-17A and IL-21 levels during induction therapy, and to assess their relationship with disease activity and immunologic features on patients with active lupus nephritis, twenty-eight patients treated with corticosteroid and immunosuppressants were included in this study. Demographic, clinical, serological data and disease activity were assessed. Blood samples were collected at week 0, 12 and 24, and serum concentrations of IL-17A, IL-6 and IL-21 were measured by cytometric bead array. The serum concentrations of IL-6, IL-17A and IL-21 (P<0.001, P<0.01, P=0.001, respectively) decreased progressively during induction therapy. Concentration of IL-6, IL-17A and IL-21 was higher in non-remission group than that in remission group. A positive correlation was established between the concentration of these cytokines and the severity of proteinuria (P<0.001, P=0.020, P=0.045, respectively), ESR (P<0.001), SLEDAI scores (P<0.05), and ANA titers (P=0.018, P=0.048, P<0.05, respectively). Additionally, ROC curve analysis for IL-6, IL-17A and IL-21 was performed to predict the disease activity. The optimal cutoff level was 5.78 pg/ml, 1.98 pg/ml and 8.59 pg/ml, with AUC=0.809, 0.735 and 0.786. The concentration of IL-6 and IL-21 may be regarded as an indicator for the remission of active lupus nephritis, with cutoff value of 9.12 pg/ml and 11.30 pg/ml, while AUC=0.930 and 0.896. The production of serum IL-6, IL-17A and IL-21 in active LN was dramatically declined during induction therapy, which may improve disease activity while delay disease progression of LN.

Increased ratio of Th17 cells to SIGIRR+CD4+ T cells in peripheral blood of patients with SLE is associated with disease activity

To investigate the clinical significance of the ratio of T helper cell 17 (Th17) cells to single immunoglobulin IL-1-related receptor (SIGIRR)⁺ cluster of differentiation (CD4)⁺ T cells in patients with systemic lupus erythematosus (SLE), novel data and data from previous studies were analyzed. The frequency of Th17 cells in peripheral blood mononuclear cells (PBMCs) and their correlation with clinical data were evaluated in 48 patients with SLE and 38 healthy controls through flow cytometry. Compared with healthy controls, the percentage of Th17 cells was significantly increased in the PBMCs of patients with SLE (Z=-5.82, P<0.001). Compared with inactive SLE (ISLE), the percentage of Th17 cells in active SLE (ASLE) were significantly increased (Z=-4.26, P<0.0001). Compared with patients without lupus nephritis, the frequency of Th17 cells was significant increased (Z=-2.20, P=0.028). The frequency of Th17 cells was inversely correlated with the frequency of SIGIRR⁺CD4⁺ T cells (r=-0.61, P<0.001). The ratio of Th17 cells to SIGIRR⁺CD4⁺ T cells in ASLE was significantly increased compared with healthy controls or patients with ISLE (P<0.001) and was inversely correlated with complement component 3 and complement component 4, and positively correlated with SLE disease activity index and 24-h proteinuria (P<0.05). In summary, increased numbers of Th17 cells and decreased numbers of SIGIRR⁺CD4⁺ T cells in patients with SLE suggested that SIGIRR⁺CD4⁺ T and Th17 cells may be involved in the pathogenesis of SLE.

Analysis of Serum Interleukin (IL)-1β and IL-18 in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disease characterized by biological and clinical heterogeneity. The interleukin (IL)-1 superfamily is a group of innate cytokines that contribute to pathogenesis in many autoimmune diseases. IL-1β and IL-18 are two members that have been shown to play a role in murine lupus-like models, but their role in human SLE remains poorly understood. Here, IL-1β and IL-18 were quantified by enzyme-linked immunosorbent assay in the serum of healthy controls (HCs) and SLE patients from a prospectively followed cohort. Disease activity and organ damage were assessed using SLE disease activity index 2000 (SLEDAI-2K) and SLE damage index scores (SDI), respectively. 184 SLE patients (mean age 44.9 years, 91% female, 56% double-stranded deoxyribonucleic acid positive) were compared to 52 HC. SLE patients had median [IQR] SLEDAI-2K of 4 [2,6], and SDI of 1 [0–2]. Serum IL-18 levels were statistically significantly higher in SLE patients compared to HCs. Univariable linear regression analyses showed that patients with active renal disease or irreversible organ damage had statistically significantly elevated serum IL-18 levels. The association between serum IL-18 and active renal disease was confirmed in multivariable analysis after adjusting for ethnicity and organ damage. High baseline serum IL-18 levels were associated with organ damage at the subsequent visit. Serum IL-1β levels were not significantly elevated in SLE patients when compared to HCs and had no association with overall or organ-specific disease activity or organ damage in cross-sectional and longitudinal analyses. Our data suggest that serum IL-18 and IL-1β have different clinical implications in SLE, with IL-18 being potentially associated with active renal disease.

Recent advances in the development of vaccines for chronic inflammatory autoimmune diseases

Chronic inflammatory autoimmune diseases leading to target tissue destruction and disability are not only causing increase in patients' suffering but also contribute to huge economic burden for the society. General increase in life expectancy and high prevalence of these diseases both in elderly and younger population emphasize the importance of developing safe and effective vaccines. In this review, at first the possible mechanisms and risk factors associated with chronic inflammatory autoimmune diseases, such as rheumatoid arthritis (RA), multiple sclerosis (MS), systemic lupus erythematosus (SLE) and type 1 diabetes (T1D) are discussed. Current advances in the development of vaccines for such autoimmune diseases, particularly those based on DNA, altered peptide ligands and peptide loaded MHC II complexes are discussed in detail. Finally, strategies for improving the efficacy of potential vaccines are explored.

IDO chronic immune activation and tryptophan metabolic pathway: A potential pathophysiological link between depression and obesity

Obesity and depression are among the most pressing health problems in the contemporary world. Obesity and depression share a bidirectional relationship, whereby each condition increases the risk of the other. By inference, shared pathways may underpin the comorbidity between obesity and depression. Activation of cell-mediated immunity (CMI) is a key factor in the pathophysiology of depression. CMI cytokines, including IFN-γ, TNFα and IL-1β, induce the catabolism of tryptophan (TRY) by stimulating indoleamine 2,3-dioxygenase (IDO) resulting in the synthesis of kynurenine (KYN) and other tryptophan catabolites (TRYCATs). In the CNS, TRYCATs have been related to oxidative damage, inflammation, mitochondrial dysfunction, cytotoxicity, excitotoxicity, neurotoxicity and lowered neuroplasticity. The pathophysiology of obesity is also associated with a state of aberrant inflammation that activates aryl hydrocarbon receptor (AHR), a pathway involved in the detection of intracellular or environmental changes as well as with increases in the production of TRYCATs, being KYN an agonists of AHR. Both AHR and TRYCATS are involved in obesity and related metabolic disorders. These changes in the TRYCAT pathway may contribute to the onset of neuropsychiatric symptoms in obesity. This paper reviews the role of immune activation, IDO stimulation and increased TRYCAT production in the pathophysiology of depression and obesity. Here we suggest that increased synthesis of detrimental TRYCATs is implicated in comorbid obesity and depression and is a new drug target to treat both diseases.

Cytokines in systemic lupus erythematosus: far beyond Th1/Th2 dualism lupus: cytokine profiles

The aims of this study were to delineate cytokine profiles of systemic lupus erythematosus (SLE), construct prediction models for diagnosis and disease activity using those profiles, and to examine the associations between TNFB Ncol polymorphism, body mass index (BMI) and vitamin D levels with cytokine levels. Two hundred SLE patients and 196 healthy controls participated in this case-control study. Plasma cytokines levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-1β, IL- 4, IL-6, IL-10, IL-12 and IL-17 were measured and cytokines profiles were computed. IL-6, IL-12, IL-17, IFN-γ and IL-10 levels were significantly higher in SLE, while IL-4 was lower in SLE. The Th1/Th2 and Th1+Th17/Th2 profiles were significantly higher in SLE than in healthy controls, whereas there were no significant differences in the proinflammatory cytokine profile (TNFα+IL-6+IL-1β). In total, 90.4% of all subjects were correctly classified using Th1+Th17 profile and IL-10 (positively associated) and IL-4 (negatively associated) as predictor variables (sensitivity=66.7% and specificity=96.9%). In all, 20.9% of the variance in the SLE Disease Activity Index was predicted by the Th1+Th17/Th2 ratio, IL-10 and BMI (all positively) and proinflammatory profile (inversely associated). B1/B1 genotype is accompanied by increased IL-17 and Th17/Th2 ratio, while B1/B2 genotype is accompanied by higher IL-4 and IFNγ values. 25-OH vitamin D was inversely associated with IFN-γ levels. SLE is accompanied by Th1, Th17 and Treg profile and lowered IL-4 production. Lowered vitamin D levels and B1/B1 genotype, but not BMI, contribute to changes in cytokines profiles. Future treatments should target Th1, Th2 and Th17 profiles rather than inflammatory cytokines.

Intracellular accumulation and immunological responses of lipid modified magnetic iron nanoparticles in mouse antigen processing cells

Lipid modified magnetic nanoparticles could enhance the intracellular accumulation and immune responses of mouse antigen processing cells.