PD1/PDL1 expression is associated with increased TIM3 expression and tumor-infiltrating T lymphocytes in fibroblastic tumors.

PURPOSE: The combined therapy of inhibiting T cell immunoglobulin domain and mucin domain 3 (TIM3) and programmed cell death 1/programmed death-ligand 1 (PD1/PDL1) has shown encouraging therapeutic effects in some solid tumors. However, the expression of PD1/PDL1 and TIM3 in fibroblastic tumors is ill defined, which has limited the application of these immune checkpoint inhibitors in such tumors. METHODS: Immunostaining of 68 tissue microarray cores of fibroblastic tumors, including intermediate dermatofibrosarcoma protuberans and malignant myxofibrosarcoma and adult-type fibrosarcoma, was used to determine the expression of PD1, PDL1 and TIM3, as well as their relationship with the accumulation of tumor-infiltrating T lymphocytes (TILs). RESULTS: Both PD1 and PDL1 expression was only observed in a small proportion of fibroblastic tumors, whereas TIM3 was expressed in almost all tumors. However, only the positive expression of PDL1 was related to tumors with high grade and staging. A considerable number of TILs, including CD4- and CD8A-positive T cells and a small group of FoxP3-positive T cells, was also observed in most tumors. The density of TIM3 was positively correlated with that of TILs. Furthermore, higher densities of TIM3, CD4, CD8A and FoxP3 were observed in PD1 and PDL1 double-positive fibroblastic tumors. CONCLUSIONS: This study indicates that TILs with high expression of TIM3 may contribute to immunosuppression in the tumor microenvironment of fibroblastic tumors. Patients with fibroblastic tumors with high expression of PD1/PDL1 and TIM3 may therefore benefit from combination therapy with PD1/PDL1 and TIM3 inhibitors.

Involvement of the Tim-3 Pathway in the Pathogenesis of Pre-Eclampsia.

Current methods of early diagnosis and prevention of pre-eclampsia (PE) are limited; the only available definite treatment is the initiation of delivery and complete removal of the placenta. Inappropriate activation of the immune system is thought to play considerable roles in PE. T cell immunoglobulin mucin-3 (Tim-3) has been reported to regulate immune responses and play important roles in maternal-fetal tolerance during early pregnancy. In this study, we investigated the functional regulation of Tim-3 in the maternal-fetal crosstalk during 3rd-trimester healthy pregnancy and its possible role in the pathogenesis of PE. We found that Tim-3 expression on decidual immune cells was associated with production of anti-inflammatory cytokines. Tim-3 pathway blockade resulted in higher IFN-γ but lower IL-4 and IL-10 production. Using a tube formation assay between HTR8/SVneo cells and human umbilical vein endothelial cells, we found that Tim-3 pathway blockade inhibits tube formation and reversed by addition of recombinant IL-4 and/or IL-10. Pre-eclamptic patients showed reduced Tim-3 expression on both decidual and peripheral immune cells (especially on peripheral CD8+T cells). Therefore, we proposed that abnormal Tim-3 signal resulted in immunological imbalance at the maternal-fetal interface and may be involved in the progress of PE by affecting uterine spiral artery remodeling. Our study expanded the regulatory function of Tim-3 signaling pathway to the 3rd-trimester pregnancy and provided a new target for early warning and therapeutic strategies of PE.

Correlation of Tim-3 expression with chemokine levels for predicting the prognosis of patients with glioblastoma.

Glioblastoma (GBM) immunotherapy, which blocks the checkpoint inhibitor molecule T cell immunoglobulin domain and mucin domain-3 (Tim-3), has potential therapeutic applications. However, not all patients do benefit from the targeted therapy. This study aimed to explore Tim-3 expression correlated chemokine profiles and immune cell infiltration and investigate their potential as prognostic markers of glioblastoma (GBM) immunotherapy. We analyzed transcriptional data of GBM from TCGA database, to measure Tim-3 expression by R package DESeq2 analysis and observed differentially expressed genes in GBM samples with high Tim-3 expression levels. We also probed the relative gene enrichment pathways. Tim-3 expression was evident in biological processes including the recruitment of immune cells. We also identified some chemokines related to Tim-3 expression. The expression levels of CCL18, CXCL13 and CCL7 were significantly higher in GBM tissues with high Tim-3 expression than in GBM tissues with low Tim-3 expression. In addition, exploring the relationship between immune cell infiltration and Tim-3 expression suggested that Tim-3 expression was positively related to significant immune cell infiltration.

Pronounce expression of Tim-3 and CD39 but not PD1 defines CD8 T cells in critical Covid-19 patients.

BACKGROUND: During viral infection, inhibitory receptors play a key role in regulating CD8 T-cell activity. The objective of this research was to investigate programmed cell death protein 1 (PD-1), T-cell immunoglobulin and mucin domain-containing protein-3 (TIM-3), and CD39 exhaustion markers in CD8 T cells of new coronavirus disease-2019 (COVID-19) patients. METHODS: A total of 44 patients with COVID-19 (17 subjects in a critical group and 27 patients in a non-critical group) and 14 healthy controls, who were admitted to Hospitals in Babol, were recruited to the study. In subjects' peripheral blood mononuclear cells (PBMCs), we compared the phenotype of CD8 T lymphocytes, expressing PD-1, TIM-3, or CD39, both alone and in various combinations. RESULTS: The findings showed that the percentage of CD8+ cells was significantly lower in patients. Critical and non-critical patients were more likely than healthy controls to have an escalated frequency of CD8+ TIM-3+, CD8+ CD39+, and CD8+ TIM-3+ CD39+ cells. No significant differences were observed between all groups in the CD8+ PD-1+ cell counts. There was also no difference between three groups regarding the counts of CD8+ TIM-3+ PD-1+, CD8+ PD-1+ CD39+, and CD8+ TIM-3+ PD-1+ CD39+ cells. The counts of non-exhausted cells were significantly lower in critical and non-critical individuals compared to the healthy individuals' value. CONCLUSION: Patients, infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), altered exhausted CD8 T lymphocytes with CD39 and TIM-3 exhaustion markers, which may account the dysregulated immune response found in COVID-19.

Distribution of novel immune-checkpoint targets in ovarian cancer tumor microenvironment: A dynamic landscape.

BACKGROUND: The disappointing activity of single agent immune-checkpoint inhibitors in epitherlial ovarian cancer (EOC) has been attributed in part to its unique tumor microenvironment (TME). IDO, PDL1, LAG3 and TIM3 have been implicated in the immunotolerance of EOC. We investigated the expression of these co-regulators, their change with neoadjuvant chemotherapy (NACT), and their association with outcome. METHOD: We identified 98 patients with EOC treated with NACT and performed IDO, PDL1, LAG3 and TIM3 immunohistochemistry on samples obtained before and after NACT. The cut-off threshold to consider a positive sample was set at 5%. RESULTS: In our cohort, TIM3 was the most prevalent co-regulator, with more than 75% of the samples being TIM3 positive. In comparison, only 22%, 28% and 17% of the samples were considered IDO, PDL1 and LAG3 positive. More than half of ovarian tumors expressed 2, 3 or even all 4 co-inhibitory molecules. However, biomarkers were not correlated with each other. NACT had a marked impact on immune co-regulator expression with over 70% of patients showing a change in biomarker status from negative to positive or vice versa. There was no significant difference in the pattern of co-regulator expression between platinum-sensitive and resistant patients. Co-expression of multiple inhibitory molecules did not appear to affect overall and progression-free survival. CONCLUSION: TIM3 is the most abundant co-inhibitory molecule in OC and may represent an attractive target. In addition, OC frequently co-expressed 2 or more markers supporting ICI combinatorial approaches. Finally, NACT significantly altered the expression of immunosuppressive molecules suggesting that the choice of ICI combinations should be adapted to the composition of the post-NACT immune TME.

TIM­3 inhibits PDGF­BB­induced atherogenic responses in human artery vascular smooth muscle cells.

Increasing evidence suggests that T­cell immunoglobulin and mucin domain 3 (TIM­3) displays anti­atherosclerotic effects, but its role in vascular smooth muscle cells (VSMCs) has not been reported. The present study aimed to investigate the function of TIM­3 and its roles in human artery VSMCs (HASMCs). A protein array was used to investigate the TIM­3 protein expression profile, which indicated that TIM­3 expression was increased in the serum of patients with lower extremity arteriosclerosis obliterans disease (LEAOD) compared with healthy individuals. Immunohistochemistry and western blotting of arterial tissue further revealed that TIM­3 expression was increased in LEAOD artery tissue compared with normal artery tissue. Additionally, platelet­derived growth factor­BB (PDGF­BB) displayed a positive correlation with TIM­3 expression in HASMCs. TIM­3 decreased the migration and proliferation of PDGF­BB­induced HASMCs, and anti­TIM­3 blocked the effects of TIM­3. The effect of TIM­3 on the proliferation and migration of HASMCs was further investigated using LV­TIM­3­transduced cells. The results revealed that TIM­3 also inhibited PDGF­BB­induced expression of the inflammatory factors interleukin­6 and tumor necrosis factor­α by suppressing NF­κB activation. In summary, the present study revealed that TIM­3 displayed a regulatory role during the PDGF­BB­induced inflammatory reaction in HASMCs, which indicated that TIM­3 may display anti­atherosclerotic effects.

Significance of TIM-3 Expression in Resected Esophageal Squamous Cell Carcinoma.

BACKGROUND: T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) is a promising checkpoint. However, its features and prognostic value remain undetermined in esophageal squamous cell carcinoma (ESCC). This study evaluated the prognostic value of TIM-3 expression and its relationship with programmed cell death 1 (PD-1) and CD8+ tumor-infiltrating lymphocytes (TILs) in patients with surgically resected ESCC. METHODS: Expression levels of TIM-3, PD-1, and CD8+ TILs in ESCC were determined by immunohistochemistry. The association between clinicopathologic features or clinical outcomes and TIM-3 expression was analyzed. RESULTS: A total of 183 patients with ESCC who had undergone esophagectomy without implementation of neoadjuvant therapy at the Second Affiliated Hospital of Soochow University in Suzhou, China from January 2009 to December 2014 were included. PD-1 positivity (P = .032) and high CD8+ TIL density (P = .035) significantly correlated with positive TIM-3 expression. TIM-3 positivity was an independent risk factor for recurrence-free survival (RFS) (P < .001) and overall survival (OS) (P < .001). Subgroup analysis revealed that the TIM-3+PD-1+CD8 low group had the worst RFS and OS, whereas the TIM-3-PD-1-CD8 high group had the best RFS and OS (RFS: log-rank test P < .001; OS: log-rank test P < .001). CONCLUSIONS: Positive TIM-3 expression was associated with PD-1 positivity and high CD8+ TIL density and was an independent risk factor for RFS and OS in ESCC. Furthermore, the combination of TIM-3 and PD-1 expression or CD8+ TIL density could further stratify patients into different groups with distinct prognosis.

Proliferating Transitory T Cells with an Effector-like Transcriptional Signature Emerge from PD-1+ Stem-like CD8+ T Cells during Chronic Infection.

T cell dysfunction is a characteristic feature of chronic viral infection and cancer. Recent studies in chronic lymphocytic choriomeningitis virus (LCMV) infection have defined a PD-1+ Tcf-1+ CD8+ T cell subset capable of self-renewal and differentiation into more terminally differentiated cells that downregulate Tcf-1 and express additional inhibitory molecules such as Tim3. Here, we demonstrated that expression of the glycoprotein CD101 divides this terminally differentiated population into two subsets. Stem-like Tcf-1+ CD8+ T cells initially differentiated into a transitory population of CD101-Tim3+ cells that later converted into CD101+ Tim3+ cells. Recently generated CD101-Tim3+ cells proliferated in vivo, contributed to viral control, and were marked by an effector-like transcriptional signature including expression of the chemokine receptor CX3CR1, pro-inflammatory cytokines, and granzyme B. PD-1 pathway blockade increased the numbers of CD101-Tim3+ CD8+ T cells, suggesting that these newly generated transitional cells play a critical role in PD-1-based immunotherapy.

Sequential monitoring of TIM-3 mRNA expression in blood and urine samples of renal transplant recipients.

BACKGROUND: T cell immunoglobulin and mucin domain 3 (TIM-3), as a co-inhibitory receptor expressed on Th1, Th17, CD8T, FoxP3 + Treg and innate immune cells, plays an important role in suppression of T cell-mediated immune responses, tolerance induction and T cell exhaustion. In this study, we evaluated sequential alterations of TIM-3 mRNA expression level in blood and urine samples of renal transplant recipients to predict approaching clinical episodes. METHODS: A total of 52 adult renal transplant recipients (31 male and 21 female) were enrolled in this study. All the patients received kidney transplant from living unrelated donors. TIM-3 mRNA expression in peripheral blood mononuclear cells (PBMCs) and urinary cells were quantified using Real Time TaqMan polymerase chain reaction (PCR) at 4 different time points (pre-transplantation, 2, 90 and 180 days post-transplantation). RESULT: TIM-3 mRNA expression level on days 2, 90 and 180 after transplantation was significantly higher in blood and urine samples of patients with graft dysfunction (GD) compared with patients with well-functioning graft (WFG). Our results also showed a high correlation between blood and urinary level of TIM-3 mRNA expression. The data from Receiver Operating Characteristic (ROC) Curve Analysis showed that blood and urinary TIM-3 mRNA expression level at month 3 and 6 could discriminate graft dysfunction (GD) from well-functioning graft (WFG) with high specificity and sensitivity. CONCLUSION: Our data suggested that serial monitoring of TIM-3 mRNA level in the blood and urine samples of renal transplant recipients could be a useful non-invasive biomarker for prediction and diagnosis of allograft dysfunction.

Regulation of TIM-3 expression in a human T cell line by tumor-conditioned media and cyclic AMP-dependent signaling.

T cell immunoglobulin and mucin domain-3 (TIM-3) expression increases in exhausted T cells, which inhibits T cell function. TIM-3 expression is supposedly up-regulated in tumor-bearing individuals via chronic antigenic stimulation of T cells. Considering the immunosuppressive nature of the tumor microenvironment, we investigated whether tumor-secreted molecules might enhance TIM-3 expression in Jurkat T cells. We observed that TIM-3 expression was increased by the activation of prostaglandin (PG) E2 and cyclic AMP (cAMP) signaling pathways. Adenylate cyclase activation led to protein kinase A (PKA)-dependent upregulation of the TIM-3 minimal promoter region and of upstream conserved non-coding sequences. TIM-3 expression in Jurkat T cells was increased by the exposure to breast tumor cell-conditioned media partially through the interaction between PGE2 and its receptor, EP4. Our results propose that tumor-secreted molecules such as PGE2, which activates PKA and EPAC, may regulate TIM-3 expression in T cells.

Tim-3 expression and its role in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common tumors in the world, and its mortality is still on the rise. Limited treatments and low chemotherapy sensitivity of HCC make new therapeutic strategies urgently needed. With the rise of immune checkpoint blockade, anti-CTLA-4 antibodies and anti-PD-1 antibodies have shown therapeutic effects in various tumors. T cell immunoglobulin mucin-3 (Tim-3), a newly discovered immune checkpoint molecule, plays a major role in the development of HCC. Tim-3 can be used to evaluate the prognosis and therapeutic effects in HCC, and Tim-3 intervention has shown anti-tumor effects in preclinical experiments. This review summarizes findings regarding Tim-3 and HCC in recent years and discusses the rationale of Tim-3 as a therapeutic target for HCC.

Expression of Tim-3 in peripheral blood mononuclear cells and placental tissue in unexplained recurrent spontaneous abortion.

The expression of T-cell immunoglobulin domain, mucin domain-3 (Tim-3) in unexplained recurrent spontaneous abortion (URSA) was investigated.Tim-3 mRNA expression in peripheral blood mononuclear cells (PBMCs) of URSA and control groups was assayed by fluorescent quantitative real-time polymerase chain reaction. Tim-3 protein expression intensity and localization in placental villi and uterine decidua were determined using immunohistochemical assay. The CD4Tim-3/CD4 cell ratio in PBMCs was determined by flow cytometry.Tim-3 mRNA expression in PBMCs was significantly higher in URSA than in normal controls (1.32 ±â€Š0.25 vs 1.20 ±â€Š0.12, P < .05). Tim-3 was expressed in placental tissue from both URSA patients and normal pregnant females (controls); however, the expression intensity was higher in the URSA group (0.54 ±â€Š0.31 vs 0.35 ±â€Š0.22, P < .05). CD4Tim-3/CD4 cell ratio in PBMCs was significantly higher in the URSA group than that in the control group (4.53 ±â€Š1.66% vs 1.28 ±â€Š0.71%, P < .05).Increased Tim-3 expression in PBMCs and placental tissue of URSA might affect maternal-fetal immune tolerance. Tim-3 was involved in the pathogenesis of URSA, which was expected to serve as an indicator for the immune evaluation of URSA.

CTLA-4, PD-1 and TIM-3 expression predominantly downregulated in MS patients.

Multiple sclerosis (MS), is an autoimmune disorder of central nervous system (CNS) characterized by inflammation and demyelination. Self-tolerance impairment is considered to be induced by a combination of inherited susceptibility and environmental agents. In this work, we demonstrate that a reduction in the comparative expression of well-known inhibitory receptors (i.e., CTLA-4, PD-1, and TIM-3) is importantly linked with MS patients compared to healthy controls. The relative expression of interested genes was performed on peripheral blood mononuclear cells (PBMCs), by using quantitative real time-PCR (qRT-PCR). Our data highlighted the role of inhibitory receptors in the maintenance of immune homeostasis in autoimmune disease.

Comparative analysis of decidual and peripheral immune cells and immune-checkpoint molecules during pregnancy in wild-type and PACAP-deficient mice.

PROBLEM: PACAP is a neuropeptide having a major relevance in the nervous system and in several peripheral organs including those of the reproductive system. PACAP-deficient mice have several morphological, biochemical, behavioral defects, and show reduced fertility. Female reproductive functions such as fertility, mating behavior, maternal behaviors, and implantation alterations have been widely investigated, but no comparative immune analyses are available in pregnant wild-type (WT) and PACAP knockout (KO) mice. METHODS OF STUDY: Therefore, we performed a detailed immunophenotyping of decidual and peripheral immune cells and investigated the expression of two immune-checkpoint molecules by immune cells together with immunohistochemistry detecting Galectin-9 in placental tissues. We investigated the percentage of numerous immune cell populations in the periphery and in the decidua of pregnant mice. RESULTS: We demonstrated a significant increase in the frequency of decidual Gal-9+ Th cells obtained from PACAP KO mice compared to the decidua of WT mice. We could not determine statistical differences in TIM-3 and programmed cell death-1 expression by different immune cells in the decidua and in the periphery between WT and KO mice. In conclusion, we could not find any significant alteration either in the distribution or in the cytotoxicity of the investigated decidual immune cells which could elucidate any reproductive alterations in PACAP KO mice. CONCLUSION: The only remarkable finding is the recruitment of Gal-9+ Th cells to the decidua promoting local immune homeostasis in PACAP KO mice, which nevertheless cannot explain the reduced fertility observed in these mice.

Evaluation of the effect of TIM-3 suppression by miR-498 and its effect on apoptosis and proliferation rate of HL-60 cell line.

BACKGROUND: Acute Myeloid Leukemia (AML) is a Cancer of hematopoietic stem cells with a rapid progression. TIM-3 is expressed on leukemic stem cells (LSCs) in most types of AML and might have a positive effect on maintenance of malignant phenotype. MicroRNAs play important roles in either cancer progression or suppression. In this study were evaluated, the inhibitory effect of miR-498 on TIM-3 expression and its impact on proliferation and survival of HL-60 cell line. METHODS: Firstly, the probable inhibitory effect of miR-498 on TIM-3 expression was predicted. HL-60 cells were cultured and expression of TIM-3 was induced on the cells using phorbol miristate acetate. The cells were transfected with miR-498 and expression level of TIM-3 were measured using with q-RT-PCR and flow cytometry methods. In addition, the effect of suppression of TIM-3 expression in HL-60 cell line was analyzed with apoptosis and cell proliferation assays. RESULTS: Bioinformatics analyses predicted that miR-498 has high ability to silence TIM-3 gene expression. Our experiments confirmed that miR-498 was able to strongly silence TIM-3 expression (68% silencing) in HL-60 cell line (P < 0.002). Also, the cells with suppressed expression of TIM-3 had a lower proliferation and higher apoptosis rates. CONCLUSION: Based on our results, the miR-498 can effectively suppress TIM-3 expression in the AML cell line. TIM-3 suppression, in turn, inhibits malignant cell proliferation and induces its apoptosis. Collectively, suppression of TIM-3 by miR-498 can be considered as a potential powerful way for treatment of AML.

Different aberrant expression pattern of immune checkpoint receptors in patients with PTCL and NK/T-CL.

AIM: To better understand the T-cell immunodeficiency status in patients with peripheral T-cell lymphomas (PTCLs) and NK/T-cell lymphomas (NK/T-CLs), the T-cell inhibitory receptors expression pattern was investigated. METHODS: The expression levels of programmed death 1 (PD-1), cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), B/T lymphocyte attenuator (BTLA), lymphocyte-activation gene 3 (LAG-3), T-cell immunoglobulin-3 (TIM-3), T-cell immunoglobulin and ITIM domain (TIGIT) genes were detected in peripheral blood mononuclear cells (PBMCs) from patients and healthy volunteers by quantitative real-time-PCR, the correlation between different gene expression levels was analyzed. RESULTS: Significantly higher expression of PD-1, CTLA-4, BTLA, LAG-3, TIM-3 and TIGIT can be observed as a common characteristic in patients with PTCL or NK/T-CL. However, the coexpression pattern seemed different between subtypes. Their overexpression is also related to disease progression stage. CONCLUSION: We first characterized the expression pattern of six T-cell inhibitory receptor genes in PTCL and NK/T-CL, which might work as immune biomarkers for evaluation the immunosuppression status and help to establish the precision targets of immunotherapy.

Expression of TIM-3 and LAG-3 in extranodal NK/T cell lymphoma, nasal type.

OBJECTIVE: To investigate the expression of TIM-3 and LAG-3 in extranodal NK/T cell lymphoma, nasal type (ENKTL), and evaluate the clinical and prognostic significance of TIM-3 and LAG-3 in ENKTL. METHODS: A total of 61 human paraffin-embedded specimens including 41 ENKTL and 20 rhinitis were involved. We performed immunohistochemistry to detect the expression of TIM-3 and LAG-3. We analyzed correlation between expression of TIM-3 and LAG-3 and clinicopathological features of ENKTL. RESULTS: TIM-3 was positively expressed in 95 (39/41) ENKTL compared with 55% (11/20) in rhinitis, LAG-3 was positively expressed in 95 (39/41) ENKTL compared with 45% (9/20) in rhinitis. A positive correlation was found between TIM-3 and LAG-3. TIM-3 and LAG-3 had no significant correlation with ENKTL patients' age, gender, international prognostic index (IPI) score, B symptoms, LDH level, Ann Arbor stage and treatment regimens. High expression of TIM-3, high IPI score, elevated LDH level and late Ann Arbor stage were shown to be correlated with worse progression free survival (PFS). A multivariate COX regression model show that TIM-3 high expression rate was an independent prognostic factor for ENKTL patients' PFS. CONCLUSIONS: Our findings indicate that TIM-3 might be a promising predictive indicator for the ENKTL patients.

Tim-3 expression predicts the abnormal innate immune status and poor prognosis of glioma patients.

Malignant glioma, the most common and devastating primary brain tumor, has serious effects on human health with high risk of recurrence and short survival periods. Recently, the exploitation of immunological mechanisms shed new lights for developing novel therapeutic strategies for glioma pathogenesis. Tim-3, a member of T cell immunoglobulin and mucin domain family, has been involved in multiple diseases, including tumor, by regulating the viability and function of immunocytes. In the present study, we detected Tim-3 expression on peripheral innate immunocytes from glioma patients and analyzed their correlation with clinical indices. We found that the number of CD3-CD56+ NK cells decreased in glioma patients. Compared with healthy controls, glioma patients had higher Tim-3 expression on peripheral CD3-CD56+ NK cells and CD14+ monocytes. Tim-3+ NK cells had decreased capability of IFN-r secretion, while Tim-3+ monocytes showed a M2-like phenotype. Importantly, Tim-3 level on both NK cells and monocytes positively correlated with the ratio of Ki-67+ tumor cells. Moreover, patients with high percentage of Tim-3+ monocytes showed high risk of recurrence or death. Our present work gives new insights into the innate immune mechanisms in glioma and might provide new evidences for the clinical practice of Tim-3-based immunotherapy in glioma.

Clinical Significance of T-Cell Immunoglobulin Mucin 3 Expression on Peripheral Blood Mononuclear Cells in Pediatric Acute Immune Thrombocytopenia.

T-cell immunoglobulin mucin 3 (TIM-3) is a transmembrane protein that plays an important role in several autoimmune diseases. The relationship between TIM-3 and excessive immune responses in immune thrombocytopenia (ITP) is still unknown. In this study, we evaluated the relationship between the expression of TIM-3 on peripheral blood mononuclear cells in patients with ITP and the disease severity. The frequency of lymphocyte and monocyte subsets and their TIM-3 expression were evaluated in patients with acute ITP (n = 45) and in healthy control (n = 20) using flow cytometry. Based on bleeding severity, patients were classified into 3 subgroups as mild (n = 12), moderate (n = 25), and severe (n = 8) bleeding. T-helper lymphocytes was found to be significantly decreased in the severe bleeding group compared to the mild and moderate bleeding groups, while CD56high natural killer (NK) cells were significantly expanded in severe bleeding group. In contrast, classical, intermediate, and nonclassical monocytes, natural killer T lymphocyte (NKT), and CD56dim NK cells showed no significant changes among different patient groups. This alteration of lymphocyte and monocyte subsets was associated with significant decrease in TIM-3 expression on CD56high NK cells, T-helper lymphocytes, NKT cells, and nonclassical monocytes in patients with ITP compared to the controls. Lower level of TIM-3 was found in severe bleeding group compared to mild and moderate bleeding groups. These results indicate that TIM-3 may be involved in the pathogenesis of ITP which subsequently can represent an opportunity for new therapeutic plan, moreover. This may have a prognostic value for disease severity.

Conjugated Bilirubin Upregulates TIM-3 Expression on CD4+CD25+ T Cells: Anti-Inflammatory Implications for Hepatitis A Virus Infection.

Bilirubin (BR), a metabolite with increased concentrations in plasma during viral hepatitis, has been recognized as a potential immune-modulator. We recently reported that conjugated BR (CB) augments regulatory T cell (Treg) suppressor activity during acute hepatitis A virus (HAV) infection. However, the mechanisms related to the effects of CB on Treg function in the course of hepatotropic viral diseases have not been elucidated. T cell immunoglobulin domain and mucin domain 3 (TIM-3), via its interactions with galectin-9 (GAL-9), is a receptor associated with enhanced Treg function. Thus, TIM-3 expression may be related to the crosstalk between CB and Tregs during HAV infection. Herein, in vitro treatment with high concentrations of CB upregulated TIM-3 expression on Tregs from healthy donors. CB treatment in vitro did not induce de novo Treg generation, and in vitro stimulation with TGF-ß, which shows increased secretion during HAV infection, resulted in a trend toward increased TIM-3 expression on Tregs and CD4+ T lymphocytes (TLs) from healthy donors. Interestingly, an upregulation of TIM-3 expression on CD4+CD25+ T cells and an increase in the proportion of CD4+ TLs expressing GAL-9 were found in HAV-infected patients with abnormal CB values relative to healthy controls. In addition, a statistically significantly reduction in IL-17F production was observed after treatment of CD4+ TLs from healthy donors with high doses of CB in vitro. In summary, our results suggest that CB might regulate Treg activity via a TIM-3-mediated mechanism, ultimately leading to an anti-inflammatory hepatoprotective effect.