Clinical significance of serum soluble T-cell immunoglobulin and mucin domain 3 levels in systemic sclerosis: Association with disease severity

Soluble form of immune checkpoints in autoimmune diseases

Immune checkpoints are essential regulators of immune responses, either by activating or suppressing them. Consequently, they are regarded as pivotal elements in the management of infections, cancer, and autoimmune disorders. In recent years, researchers have identified numerous soluble immune checkpoints that are produced through various mechanisms and demonstrated biological activity. These soluble immune checkpoints can be produced and distributed in the bloodstream and various tissues, with their roles in immune response dysregulation and autoimmunity extensively documented. This review aims to provide a thorough overview of the generation of various soluble immune checkpoints, such as sPD-1, sCTLA-4, sTim-3, s4-1BB, sBTLA, sLAG-3, sCD200, and the B7 family, and their importance as indicators for the diagnosis and prediction of autoimmune conditions. Furthermore, the review will investigate the potential pathological mechanisms of soluble immune checkpoints in autoimmune diseases, emphasizing their association with autoimmune diseases development, prognosis, and treatment.

The role of TIM-3 in sepsis: a promising target for immunotherapy?

Sepsis remains a significant cause of mortality and morbidity worldwide, with limited effective treatment options. The T-cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3) has emerged as a potential therapeutic target in various immune-related disorders. This narrative review aims to explore the role of TIM-3 in sepsis and evaluate its potential as a promising target for immunotherapy. We discuss the dynamic expression patterns of TIM-3 during sepsis and its involvement in regulating immune responses. Furthermore, we examine the preclinical studies investigating the regulation of TIM-3 signaling pathways in septic models, highlighting the potential therapeutic benefits and challenges associated with targeting TIM-3. Overall, this review emphasizes the importance of TIM-3 in sepsis pathogenesis and underscores the promising prospects of TIM-3-based immunotherapy as a potential strategy to combat this life-threatening condition.

Soluble TIM-3 as a biomarker of progression and therapeutic response in cancers and other of human diseases

Immune checkpoints inhibition is a privileged approach to combat cancers and other human diseases. The TIM-3 (T cell immunoglobulin and mucin-domain containing-3) inhibitory checkpoint expressed on different types of immune cells is actively investigated as an anticancer target, with a dozen of monoclonal antibodies in (pre)clinical development. A soluble form sTIM-3 can be found in the plasma of patients with cancer and other diseases. This active circulating protein originates from the proteolytic cleavage by two ADAM metalloproteases of the membrane receptor shared by tumor and non-tumor cells, and extracellular vesicles. In most cancers but not all, overexpression of mTIM-3 at the cell surface leads to high level of sTIM-3. Similarly, elevated levels of sTIM-3 have been reported in chronic autoimmune diseases, inflammatory gastro-intestinal diseases, certain viral and parasitic diseases, but also in cases of organ transplantation and in pregnancy-related pathologies. We have analyzed the origin of sTIM-3, its methods of dosage in blood or plasma, its presence in multiple diseases and its potential role as a biomarker to follow disease progression and/or the treatment response. In contrast to sPD-L1 generated by different classes of proteases and by alternative splicing, sTIM-3 is uniquely produced upon ADAM-dependent shedding, providing a more homogenous molecular entity and a possibly more reliable molecular marker. However, the biological functionality of sTIM-3 remains insufficiently characterized. The review shed light on pathologies associated with an altered expression of sTIM-3 in human plasma and the possibility to use sTIM-3 as a diagnostic or therapeutic marker.

The Pathophysiological Roles of Regulatory T Cells in the Early Phase of Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune disease that is characterized by vascular damage and fibrosis. Both clinical manifestations and immunological disturbances are diverse according to the disease duration. Particularly, changes in immunological processes are prominent in the early phase of SSc. The orchestration of several subsets of immune cells promotes autoimmune responses and inflammation, and eventually stimulates pro-fibrotic processes. Many reports have indicated that CD4+ T cells play pivotal roles in pathogenesis in the early phase of SSc. In particular, the pathogenic roles of regulatory T (Treg) cells have been investigated. Although the results were controversial, recent reports suggested an increase of Treg cells in the early phase of SSc patients. Treg cells secrete transforming growth factor-β (TGF-β), which promotes myofibroblast activation and fibrosis. In addition, the dysfunction of Treg cells in the early phase of SSc was reported, which results in the development of autoimmunity and inflammation. Notably, Treg cells have the plasticity to convert to T-helper17 (Th17) cells under pro-inflammatory conditions. Th17 cells secrete IL-17A, which could also promote myofibroblast transformation and fibrosis and contributes to vasculopathy, although the issue is still controversial. Our recent transcriptomic comparison between the early and late phases of SSc revealed a clear difference of gene expression patterns only in Treg cells. The gene signature of an activated Treg cell subpopulation was expanded in the early phase of SSc and the oxidative phosphorylation pathway was enhanced, which can promote Th17 differentiation. And this result was accompanied by the increase in Th17 cells frequency. Therefore, an imbalance between Treg and Th17 cells could also have an important role in the pathogenesis of the early phase of SSc. In this review, we outlined the roles of Treg cells in the early phase of SSc, summarizing the data of both human and mouse models. The contributions of Treg cells to autoimmunity, vasculopathy, and fibrosis were revealed, based on the dysfunction and imbalance of Treg cells. We also referred to the potential development in treatment strategies in SSc.

Soluble TIM3 and Its Ligands Galectin-9 and CEACAM1 Are in Disequilibrium During Alcohol-Related Liver Disease and Promote Impairment of Anti-bacterial Immunity

BACKGROUND AND AIMS

Immunoregulatory checkpoint receptors (CR) contribute to the profound immunoparesis observed in alcohol-related liver disease (ALD) and in vitro neutralization of inhibitory-CRs TIM3/PD1 on anti-bacterial T-cells can rescue innate and adaptive anti-bacterial immunity. Recently described soluble-CR forms can modulate immunity in inflammatory conditions, but the contributions of soluble-TIM3 and soluble-PD1 and other soluble-CRs to immune derangements in ALD remain unclear.

METHODS

In Alcoholic Hepatitis (AH; n = 19), alcohol-related cirrhosis (ARC; n = 53) and healthy control (HC; n = 27) subjects, we measured by Luminex technology (i) plasma levels of 16 soluble-CRs, 12 pro/anti-inflammatory cytokines and markers of gut bacterial translocation; (ii) pre-hepatic, post-hepatic and non-hepatic soluble-CR plasma levels in ARC patients undergoing TIPS; (iii) soluble-CRs production from ethanol-treated immunocompetent precision cut human liver slices (PCLS); (iv) whole-blood soluble-CR expression upon bacterial challenge. By FACS, we assessed the relationship between soluble-TIM3 and membrane-TIM3 and rescue of immunity in bacterial-challenged PBMCs.

RESULTS

Soluble-TIM3 was the dominant plasma soluble-CR in ALD vs. HC (p = 0.00002) and multivariate analysis identified it as the main driver of differences between groups. Soluble-CRs were strongly correlated with pro-inflammatory cytokines, gut bacterial translocation markers and clinical indices of disease severity. Ethanol exposure or bacterial challenge did not induce soluble-TIM3 production from PCLS nor from whole-blood. Bacterial challenge prompted membrane-TIM3 hyperexpression on PBMCs from ALD patient's vs. HC (p < 0.002) and was inversely correlated with plasma soluble-TIM3 levels in matched patients. TIM3 ligands soluble-Galectin-9 and soluble-CEACAM1 were elevated in ALD plasma (AH > ARC; p < 0.002). In vitro neutralization of Galectin-9 and soluble-CEACAM1 improved the defective anti-bacterial and anti-inflammatory cytokine production from E. coli-challenged PBMCs in ALD patients.

CONCLUSIONS

Alcohol-related liver disease patients exhibit supra-physiological plasma levels of soluble-TIM3, particularly those with greater disease severity. This is also associated with increased levels of soluble TIM3-ligands and membrane-TIM3 expression on immune cells. Soluble-TIM3 can block the TIM3-ligand synapse and improve anti-bacterial immunity; however, the increased levels of soluble TIM3-binding ligands in patients with ALD negate any potential immunostimulatory effects. We believe that anti-TIM3 neutralizing antibodies currently in Phase I clinical trials or soluble-TIM3 should be investigated further for their ability to enhance anti-bacterial immunity. These agents could potentially represent an innovative immune-based supportive approach to rescue anti-bacterial defenses in ALD patients.

Elevated soluble Tim-3 correlates with disease activity of systemic lupus erythematosus

T cell immunoglobulin and mucin domain-containing molecule-3(Tim-3) has been found to play important roles in systemic lupus erythematosus (SLE), but whether sTim-3 is involved in the development of SLE remains unknown. In this study, we firstly observed an increased expression of plasma sTim-3 in SLE patients, especially active SLE patients. The plasma sTim-3 levels were positively correlated with anti-dsDNA, SLEDAI score, ESR, and urine albumin. The plasma sTim-3 levels were negatively correlated with C3 and C4. The area under the ROC curve (AUC) values indicated that the plasma sTim-3 level was significantly discriminative of early active SLE from stable SLE and HC with high sensitivity and specificity. The present results suggest that sTim-3 might serve as a potential biomarker for promising the disease activity of SLE.

Serum Levels of T Cell Immunoglobulin and Mucin-Domain Containing Molecule 3 in Patients with Systemic Lupus Erythematosus

Objective: T cell immunoglobulin and mucin-domain-containing molecule 3 (TIM-3) is implicated in the development of various autoimmune diseases. We aimed to investigate the levels of soluble TIM-3 (sTIM-3) and their associations between clinical parameters in patients with systemic lupus erythematosus (SLE). Methods: Serum samples were collected from 65 patients with SLE and 35 age-matched healthy controls (HCs). The SLE Disease Activity Index 2000 (SLEDAI-2K) and the Systemic Lupus International Collaborating Clinics (SLICC) damage index (SDI) were used to assess SLE disease activity and SLE-related organ damage. British Isles Lupus Assessment Group (BILAG)-2004 index was also used to assess SLE disease activity. Soluble TIM-3 (sTIM-3) in sera from patients with SLE and HCs were evaluated by enzyme-linked immunosorbent assay (ELISA). The results were compared with the clinical parameters of SLE including SLE disease activity. Results: Serum sTIM-3 levels in patients with SLE (median 2123 pg/mL (interquartile range (IQR), 229–7235)) were significantly higher than those in HCs (1363 pg/mL; IQR, 1097–1673; p = 0.0015). Serum levels of sTIM-3 were correlated with disease activity of SLE using the SLEDAI-2K score (p < 0.001, r = 0.53). The serum sTIM-3 levels in SLE patients with active renal disease (BILAG renal index A-B) were significantly higher than those without the active renal disease (BILAG renal index C–E). However, no significant difference was observed in serum sTIM-3 levels between SLE patients with and without active involvement in other organs (BILAG index). Serum sTIM-3 levels were significantly elevated in SLE patients with organ damage (2710 pg/mL; IQR, 256–7235) compared to those without organ damage (1532 pg/mL; IQR, 228–5274), as assessed by the SDI (p = 0.0102). Conclusions: Circulating sTIM-3 levels are elevated in SLE patients, and serum sTIM-3 levels are associated with SLE disease activity and SLE-related organ damage. The data indicate a possible link between the TIM-3/Gal-9 pathway and SLE clinical phenotypes, and further investigation of the TIM-3 pathway in SLE pathophysiology is warranted.

Renal Involvement in Systemic Sclerosis: An Update

BACKGROUND

Systemic sclerosis is an immune-mediated rheumatic disease characterized by vascular abnormalities, tissue fibrosis and autoimmune phenomena.

SUMMARY

Renal disease occurring in patients with systemic sclerosis may have a variable clinicopathological picture. The most specific renal condition associated with systemic sclerosis is scleroderma renal crisis, characterized by acute onset of renal failure and severe hypertension. Although the management of scleroderma renal crisis was revolutionized by the introduction of angiotensin-converting enzyme inhibitors, there is still a significant proportion of patients with poor outcomes. Therefore, research on establishing disease markers (clinical, ultrasonographical and serological) and clear diagnostic criteria, which could limit the risk of developing scleroderma renal crisis and facilitate diagnosis of this complication, is ongoing. Other forms of renal involvement in systemic sclerosis include vasculitis, an isolated reduced glomerular filtration rate in systemic sclerosis, antiphospholipid-associated nephropathy, high intrarenal arterial stiffness and proteinuria. Key Messages: Scleroderma renal crisis is the most specific and life-threatening renal presentation of systemic sclerosis, albeit with declining prevalence. In patients with scleroderma renal crisis, it is mandatory to control blood pressure early with increasing doses of angiotensin-converting enzyme inhibitors, along with other antihypertensive drugs if necessary. There is a strong association between renal involvement and patients' outcomes in systemic sclerosis; consequently, it becomes mandatory to find markers that may be used to identify patients with an especially high risk of scleroderma renal crisis.

Level of serum soluble Tim-3 expression in early-phase acute pancreatitis

BACKGROUND/AIMS

T-cell immunoglobulin and mucin domain 3 (Tim-3) assumedly play a crucial immunomodulatory role in inflammatory response. Data on the potential role of soluble Tim-3 (sTim-3) in acute pancreatitis (AP) are scarce. We conducted a prospective clinical study to characterize its role in the early-phase AP.

METHODS

In total, 44 patients with AP (16 mild and 28 none-mild) who presented within 24 hours on admission and 20 healthy volunteers (NC) were included in our study. Serum interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α, and sTim-3 levels were detected using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Levels of the pro-inflammatory cytokines IL-6 and TNF-α and the anti-inflammatory cytokine IL-10 in the none-mild and mild groups were significantly elevated compared with those of the NC group. The sTim-3 levels of the none-mild and mild group were significantly increased compared with the NC. The sTim-3 level positively correlated with the IL-6 and TNF-α but showed no obvious correlations with the IL-10 level. The sTim-3 level positively correlated with the APACHE II score.

CONCLUSION

The results indicate that sTim-3 participates in the early progression of AP by positively regulating the pro-inflammatory cytokines and that the measurement of serum sTim-3 is an early marker for predicting AP.

Clinical Significance of Serum Galectin-9 and Soluble CD155 Levels in Patients with Systemic Sclerosis

Signaling through coinhibitory receptors downregulates the immune response to prevent excessive immune activation and maintain optimal immunity and tolerance. The aim of this study was to examine the levels of the soluble forms of coinhibitory receptors and their ligands, namely, galectin-9 (the ligand of T-cell immunoglobulin and mucin domain 3) and CD155 (the ligand of T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain), and their association with clinical features in patients with systemic sclerosis (SSc). The serum levels of galectin-9 and soluble sCD155 were examined by enzyme-linked immunosorbent assays in patients with SSc, and the results were evaluated with respect to clinical features. Patients with SSc exhibited raised serum levels of galectin-9, but not sCD155. Serum galectin-9 levels were raised not only in patients with diffuse cutaneous SSc but also in patients with limited cutaneous SSc. Furthermore, serum galectin-9 levels correlated positively with the erythrocyte sedimentation rate. In addition, increased serum galectin-9 levels tended to be associated with higher mortality and serious organ involvement. These results suggest that galectin-9, but not CD155, may be involved in the pathogenesis of SSc. In addition, the measurement of serum galectin-9 levels could be used to predict serious organ involvement and high mortality in patients with SSc.

Highly elevated soluble Tim-3 levels correlate with increased hepatocellular carcinoma risk and poor survival of hepatocellular carcinoma patients in chronic hepatitis B virus infection

Background and objective

Upregulated T-cell immunoglobulin and mucin domain containing molecule-3 (Tim-3) in hepatitis B virus (HBV)-specific CD8⁺ T-cells contributes to CD8⁺ T-cell exhaustion during chronic HBV infection. The membrane-bound Tim-3 can be cleaved from the cell surface by sheddase, yielding soluble Tim-3 (sTim-3). This study investigated serum sTim-3 levels in patients with chronic HBV infection of various liver diseases.

Methods

Serum sTim-3 levels were quantitatively determined in 288 patients with chronic HBV infection of various liver diseases. The sTim-3 levels were analyzed in relation to liver diseases including HBV-related hepatocellular carcinoma (HCC) and overall survival of HCC patients.

Results

Serum sTim-3 levels in the patients with chronic HBV infection were significantly elevated compared with healthy controls (P<0.001) and the levels from asymptomatic HBV carrier status, chronic hepatitis, liver cirrhosis to HCC were progressively increased. Serum sTim-3 levels were closely associated with the severity of liver function abnormalities. Importantly, serum sTim-3 levels were independently associated with HCC risk (OR, 4.310; 95% CI, 2.141–8.676, P<0.001) in comparison to non-HCC diseases in chronic HBV infection and significantly associated with the overall survival of HCC patients, with a level >3000 pg/mL being related to shorter overall survival than a level ≤3000 pg/mL (P=0.019).

Conclusion

Serum sTim-3 is involved in disease progression and HCC development in chronic HBV infection and its quantitative determination may be potentially used as a marker for monitoring the disease progression and predicting the HCC prognosis in chronic HBV infection.

Kidney involvement in systemic sclerosis: From pathogenesis to treatment

Among all possible systemic sclerosis internal organ complications, kidney involvement is frequently neglected or underestimated, except for the life-threatening scleroderma renal crisis. Fortunately, this severe clinical presentation is nowadays better controlled with available treatments, in particular angiotensin-converting enzyme inhibitors, and this has led to a reduction in its short- and longer-term mortality. Pathogenetic determinants are not well understood and many different other kidney involvements are possible in systemic sclerosis, including proteinuria, albuminuria, reduction of renal filtration, autoantibodies-related glomerulonephritis, and drug-related side effects. Different serological and radiological methods of evaluations are nowadays available, some representing promising diagnostic tool and prognostic outcome measure. Except for angiotensin-converting enzyme inhibitors in scleroderma renal crisis, no other treatment is currently recommended for treatment of kidney involvement in systemic sclerosis. For this reason, further studies are necessary to investigate its prognostic impact, in particular in combination with other systemic sclerosis-related internal organ manifestations. This review summarizes current available literature on kidney involvement in systemic sclerosis.