Up-regulation of Tim-3 is associated with poor prognosis of patients with colon cancer

Tim-3 (T cell immunoglobulin and mucin domain 3), belonging to the member of the novel Tim family, has been confirmed that it plays a critical negative role in regulating the immune responses against viral infection and carcinoma. Recently, it has also been reported that the over-expression of Tim-3 is associated with poor prognosis in solid tumors. However, the role of Tim-3 in colorectal cancer remains largely unknown. In the current study, we aim to investigate the expression of Tim-3 in colorectal carcinoma and discuss the relationship between Tim-3 expression and colon cancer prognosis, thus speculating the possible role of Tim-3 in colon cancer progression. Colon cancer tissues and paired normal tissue were obtained from 201 patients with colon cancer for preparation of tissue microarray. Tim-3 expression was evaluated by immunohistochemical staining. The Tim-3 expression level was evaluated by q-RT-PCR, western blot and immunocytochemistry in four colon cancer cell lines (HT-29, HCT116, LoVo, SW620). Tim-3 was expressed in 92.5% tumor tissue samples and 86.5% corresponding normal tissue samples. Expression of Tim-3 was significantly higher in tumor tissues than in normal tissues (P < 0.0001). Tim-3 expression in colon cancer tissues is in correlation with colon cancer lymphatic metastasis and TNM (P < 0.0001). Multivariate analysis demonstrated that Tim-3 expression could be a potential independent prognostic factor for colon cancer patients (P < 0.0001). Kaplan-Meier survival analysis result showed that patients with higher Tim-3 expression had a significantly shorter survival time than those with lower Tim-3 expression patients. Our results indicated that Tim-3 might participate in the tumorgenesis of colon cancer and Tim-3 expression might be a potential independent prognostic factor for patients with colorectal cancer.     

A bias in the αβ T cell receptor variable region gene usage in Takayasu's arteritis

Takayasu's arteritis (TA) is a chronic large vessel vasculitis with a predilection for the aortic arch and its branches. T lymphocytes may be important in the pathogenesis, as they have been found to infiltrate the vascular lesions. To elucidate further the role of T cells in the disease, we studied circulating CD4⁺ and CD8⁺ T cells, expression of the activation marker (HLA-DR), marker for naive (CD45RA) and primed (CD45RO) cells and the different variable α/β (AV/BV) gene segments on them. The TCR AV/BV repertoire was studied using a panel of 15 T cell receptor (TCR) V-specific MoAbs by flow cytometry in 18 patients and 23 age- and sex-matched controls. Patients had a higher percentage of AV12S1 (P< 0.05), BV6S7 (P< 0.05) and BV9 (P< 0.001)-bearing CD4⁺ cells. Patients also had a higher frequency of expansions, i.e. of T cell populations with an abnormally high TCR AV/BV gene usage. In patients' CD4⁺ subset of cells, there were 22 expansions out of 231 analyses (9.5%), whereas in controls, four were expanded out of 310 analyses (1%) (P< 0.001). For CD8⁺ cells, the frequency of expansions was 32 in 231 analyses (14%) in patients and nine out of 304 analyses in controls (3%) (P< 0.01). In addition, there was a correlation between CD4⁺ expansions and disease activity; nine out of 10 patients with active disease in comparison with two out of eight patients with inactive disease (P< 0.01) had an expansion. Some of the expanded populations in patients were phenotypically characterized and observed to be HLA-DR^<, CD28^<, CD45RA^< and CD45RO⁺, with a greater proportion being CD45RO⁺. Patients had a higher percentage of expression of HLA-DR on both CD4⁺ and CD8⁺ T cells (P< 0.01). The percentages of naive and primed CD4⁺ and CD8⁺ T cells, γδ⁺ T cells and natural killer cells were comparable to those in the control group.     

A Novel Soluble Form of Tim-3 Associated with Severe Graft-versus-Host Disease

The T cell Ig and mucin domain 3 (Tim-3) receptor has been implicated as a negative regulator of adaptive immune responses. We have utilized a proteomic strategy to identify novel proteins associated with graft versus host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT). Mass spectrometry analysis of plasma from subjects with mid-gut and upper-gut GVHD compared with those without GVHD identified increased levels of a protein identified with high confidence as Tim-3. A follow-up validation study using an immunoassay to measure Tim-3 levels in individual plasma samples from 127 patients demonstrated significantly higher plasma Tim-3 concentrations in patients with the more severe mid-gut GVHD, compared with those with upper-gut GVHD (P = .005), patients without GVHD (P = .002), and normal controls (P < .0001). Surface expression of Tim-3 was increased on CD8⁺ T cells from patients with grade 2 to 4 acute GVHD (P = .01). Mass spectrometry–based profiling of plasma from multiple subjects diagnosed with common diseases provided evidence for restricted release of soluble Tim-3 in the context of GVHD. These findings have mechanistic implications for the development of novel strategies for targeting the Tim-3 immune regulatory pathway as an approach to improving control of GVHD.     

CD4+CD29+T cells are blamed for the persistent inflammatory response in ulcerative colitis

Ulcerative colitis (UC) is a chronic gastrointestinal disorder eliciting occurrence of colorectal cancer, the third most common human malignancy. The diagnosis of UC is based on clinical symptoms combined with typical findings on endoscopy, radiology, and ultimately pathology. We investigated the variation trend of CD4⁺CD29⁺T cells together with MPO, VCAM-1 in different periods of rat UC model and UC patients. We also evaluated the relationship between CD4⁺CD29⁺T cells and disease severity. UC model was induced by administering DNCB liquid and acetate solution. We found upregulated expression of CD4⁺CD29⁺T cells in both peripheral blood and colon from rats, and a similar trend for MPO and VCAM-1 in colon (P < 0.05); the expression was especially enhanced in UC rats at two weeks after the model was established (P < 0.01). Such upregulation was also indicated in active and remission UC patients as compared to the healthy and enteritis groups (P < 0.05), with the highest expression level detected in the active UC patients (P < 0.01). Pearson correlation analysis showed a positive correlation of CD4⁺CD29⁺T cells in rat and human peripheral blood with DAI score (r_rat = 0.712, r_human = 0.677, P < 0.01), and MPO in colon (r_rat = 0.514, r_human = 0.682, P < 0.05). These results suggest that CD4⁺CD29⁺T cells may act as major effector cell subsets in persistent inflammatory responses for UC and that infiltration into colon inflammation may be induced by the combination of VCAM-1 and CD29.     

Increased Tim-3 expression on peripheral lymphocytes from patients with rheumatoid arthritis negatively correlates with disease activity

Tim-3 has been reported as an important regulatory molecule and plays a pivotal role in several autoimmunity diseases. Here, we demonstrated the increased expression of Tim-3 on peripheral CD4⁺ T, CD8⁺ T, NKT cells and monocytes from RA patients compared to those from healthy controls. Percentage of Tim-3⁺ cells in peripheral blood mononuclear cells (PBMCs) showed an inverse correlation with disease activity score 28 (DAS28) and plasma TNF-α level. Similar negative correlations were found between disease activity and Tim-3 levels on CD4⁺ T, CD8⁺ T and NKT cells. Consistently, Tim-3 expression on CD3⁺ T cells was further increased in patients with disease remission after treatment. Tim-3 expression on CD8⁺ T and NKT cells negatively correlates with plasma TNF-α. Our results suggest that Tim-3 might participate in the proceeding of RA by its negative regulation on various T cell subsets. Tim-3 might be a potential new marker for assessing severity of RA.     

Association of T cell dysfunction with the presence of IgG autoantibodies on CD4+ lymphocytes in haemophilia patients; results of a 10-year study

HIV induces progressive dysfunction followed by numerical depletion of CD4⁺ lymphocytes. IgG autoantibodies and gp120-containing immune complexes have been implicated in the pathogenesis of AIDS. We carried out a longitudinal study in 19 HIV^– and 72 HIV⁺ haemophilia patients over a 10-year period in order to investigate a possible relationship between the occurrence of autoantibodies and CD4⁺ lymphocyte changes. IgM, IgG, C3d and gp120 on the surface of CD4⁺ lymphocytes were determined in heparinized whole blood with flow cytometry and double-fluorescence. The in vitro response of autoantibody-coated cells was tested in cell cultures with concanavalin A (Con A), phytohaemagglutinin (PHA), pokeweed mitogen (PWM), anti-CD3 MoAb or pooled allogeneic stimulator cells (MLC). After a 10-year follow up, 12 of 71 HIV⁺ and 16 of 19 HIV^– haemophilia patients showed no evidence of immunoglobulins on circulating CD4⁺ lymphocytes. HIV^– haemophilia patients without autoantibodies had CD4⁺and CD8⁺ cell counts in the normal range (957 ± 642/μl and 636 ± 405/μl) and normal T cell responses in vitro (mean relative response (RR) ≥ 0.7). In contrast, HIV⁺ haemophilia patients showed immunological abnormalities which were associated with the autoantibody and immune complex load of CD4⁺ blood lymphocytes. HIV⁺ patients without autoantibodies had a mean CD4⁺ lymphocyte count of 372 ± 274/μl, a mean CD8⁺ lymphocyte count of 737 ± 435/μl, and normal T lymphocyte stimulation in vitro (mean RR ≥ 0.7). HIV⁺ patients with complement-fixing IgM on CD4⁺ lymphocytes had somewhat lower CD4⁺ (255 ± 246/μl, P= NS) and CD8⁺ (706 ± 468/μl, P= NS) lymphocyte numbers, and also normal T lymphocyte stimulation (mean RR ≥ 0.7) in vitro. However, patients with complement-fixing IgG autoantibodies showed a strong decrease of CD4⁺ (150 ± 146/μl, P< 0.02) and CD8⁺ (360 ± 300/μl, P< 0.02) lymphocytes and impaired CD4⁺ lymphocyte stimulation in vitro with a mean RR of 0.5 ± 0.5 for Con A (P= NS), 0.7 ± 0.8 for PHA (P< 0.03), 0.4 ± 0.4 for PWM (P= NS), 0.8 ± 1.2 for anti-CD3 MoAb (P< 0.04) and 0.7 ± 1.0 for pooled allogeneic stimulator cells (P= 0.05). Patients with gp120-containing immune complexes on CD4⁺ blood lymphocytes demonstrated strongly decreased CD4⁺(25 ± 35/μl, P< 0.0001) and CD8⁺ (213 ± 212/μl, P< 0.006) lymphocyte counts as well as strongly impaired T lymphocyte responses in vitro upon stimulation with PHA (RR 0.2 ± 0.1, P < 0.02), PWM (RR 0.2 ± 0.2, P= 0.05), anti-CD3 MoAb (RR 0.1 ± 0.1, P< 0.04), and allogeneic stimulator cells (RR 0.2 ± 0.1, P< 0.02). These data led us to speculate that autoantibody formation against CD4⁺ lymphocytes is an important mechanism in the pathogenesis of AIDS. We hypothesize that autoantibodies against circulating CD4⁺ lymphocytes inhibit CD4⁺ cell function, especially the release of cytokines, and induce CD4⁺ cell depletion. The reduction and dysfunction of CD4⁺ lymphocytes may be responsible for the CD8⁺ cell depletion observed in HIV⁺ patients.     

Expression of IRAK1 in lung cancer tissues and its clinicopathological significance: a microarray study

The interleukin-1 receptor associated kinases 1 (IRAK1) is a down stream effector molecule of the toll like receptor (TLR) signaling pathway, which is involved in inflammation, autoimmunity and cancer. However, the role of IRAK1 in lung cancer remains unclarified. Herein, we investigated the protein expression and the clinicopathological significance of IRAK1 in 3 formalin-fixed paraffin-embedded lung cancer tissue microarrays by using immunohistochemistry, which included 365 tumor and 30 normal lung tissues. We found that the expression of IRAK1 in lung cancer was significantly higher compared with that in normal lung tissues (P=0.002). Receiver operating characteristic (ROC) curves were generated to evaluate the power of IRAK1 to distinguish lung cancer from non-cancerous lung tissue. The area under curve (AUC) of ROC of IRAK1 was 0.643 (95% CI 0.550~0.735, P=0.009). Additionally, IRAK1 expression was related to clinical TNM stage (r=0.241, P < 0.001), lymph node metastasis (r=0.279, P < 0.001) and tumor size (r=0.299, P < 0.001) in lung cancer. In the subgroup of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), the positive rates of IRAK1 were both higher than that in the normal lung tissues (P=0.003, P=0.002, respectively). Further spearman analysis showed that IRAK1 protein in NSCLC was positive correlated with clinical TNM stage (r=0.222, P < 0.001), lymph node metastasis (r=0.277, P < 0.001), tumor size (r=0.292, P < 0.001) and distal metastasis (r=0.110, P=0.043). In conclusion, the expression of IRAK1 protein might be valuable in identifying patients with increased risks of lung cancer and might act as a target for diagnosis and gene therapy for lung cancer.     

Down-regulation of TET2 in CD3+ and CD34+ cells of myelodysplastic syndromes and enhances CD34+ cells proliferation

Aims and background: To investigate the expressions of TET2 mRNA in bone marrow CD3⁺ and CD34⁺ cells of the patients with myelodysplastic syndromes (MDS) and to study the effect of silencing TET2 by small interfering RNA (siRNA) on the biological characteristics of CD34⁺ cells. Methods: CD3⁺ and CD34⁺ cells were sorted by magnetic activated cell-sorting system from bone marrow of MDS patients and controls. The mRNA expressions of TET2 in bone marrow CD3⁺ and CD34⁺ cells of 28 MDS patients and 20 controls were detected by qPCR. The silencing effect of RNA interference (RNAi) on TET2 expression in CD34⁺ bone marrow cells of normal control was identified by qPCR and Western blot analysis. The cell cycle kinetics and cell apoptosis were then detected by flow cytometry. Results: The expression of TET2 mRNA in CD3⁺ and CD34⁺ cells was down-regulated in MDS compared with that in controls [(0.16±0.11) vs. (1.05±0.32) (P<0.001); (0.58±0.26) vs. (1.25±0.94) (P<0.005)]. The siRNA targeting TET2 suppressed the expression of TET2 in normal CD34⁺ cells. Meanwhile, the proliferation activity was significantly enhanced [G0/G1: (87.82±8.25)% vs. (92.65±7.06)% and (93.60±5.54)%, P<0.05; S: (11.50±8.31)% vs. (6.92±7.04)% and (5.95±5.53)%, P<0.05] and the apoptosis rate was declined [(21.28±9.73)% vs. (26.17±9.88)% and (26.20±9.78)%] in the cells which transfected with TET2 siRNA as compared to those in the cells transfected with scrambled siRNA and control cells. Conclusions: The TET2 expression of in CD3⁺ and CD34⁺ cells of MDS patients was decreased. Suppression of TET2 expression renders the CD34⁺ cells harboring more aggressive phenotype. This preliminary finding suggests that CD34⁺ cells lowering expression of TET2 may play an oncogenic role on myeloid tumor and CD3⁺ T cells of MDS patients may be derived from the malignant clone.     

Tim-3 Induces Th2-Biased Immunity and Alternative Macrophage Activation during Schistosoma japonicum Infection

T cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) has been regarded as an important regulatory factor in both adaptive and innate immunity. Recently, Tim-3 was reported to be involved in Th2-biased immune responses in mice infected with Schistosoma japonicum, but the exact mechanism behind the involvement of Tim-3 remains unknown. The present study aims to understand the role of Tim-3 in the immune response against S. japonicum infection. Tim-3 expression was determined by flow cytometry, and increased Tim-3 expression was observed on CD4⁺ and CD8⁺ T cells, NK1.1⁺ cells, and CD11b⁺ cells from the livers of S. japonicum-infected mice. However, the increased level of Tim-3 was lower in the spleen than in the liver, and no increase in Tim-3 expression was observed on splenic CD8⁺ T cells or CD11b⁺ cells. The schistosome-induced upregulation of Tim-3 on natural killer (NK) cells was accompanied by reduced NK cell numbers in vitro and in vivo. Tim-3 antibody blockade led to upregulation of inducible nitric oxide synthase and interleukin-12 (IL-12) mRNA in CD11b⁺ cells cocultured with soluble egg antigen and downregulation of Arg1 and IL-10, which are markers of M2 macrophages. In summary, we observed schistosome-induced expression of Tim-3 on critical immune cell populations, which may be involved in the Th2-biased immune response and alternative activation of macrophages during infection.     

Galectin-1 reduction and changes in T regulatory cells may play crucial roles in patients with unexplained recurrent spontaneous abortion

To investigate the changes of Galectin-1 and T-lymphocyte phenotypes in unexplained recurrent spontaneous abortion (URSA). Totally 60 participants were recruited and divided into 3 groups in average: pregnant patients with URSA (URSA group), normal early pregnant women with induced abortion (IA group) and normal non-pregnant women (control group). After the tissue and blood sample were collected, Galectin-1 was measured using enzyme-linked immunosorbent assay. Then the proportion of T regulatory cells was determined by flow cytometry. The expression levels of Galectin-1 in IA group and URSA group was significantly higher than that in the control group (24.30 ± 3.06 and 6.23 ± 2.41 vs. 1.30 ± 0.66, P < 0.05). Besides, the expression level of Galectin-1 in URSA group was lower than that in IA group (P < 0.05). The percentage of CD4⁺CD25⁺Foxp3⁺ Tregs was lower in URSA group than IA group (0.77 ± 0.31 vs. 1.00 ± 0.35, P < 0.05) and the ratio of CD4⁺CD25⁺Foxp3⁺/CD4⁺ in URSA group was also obviously lower than that in IA and control group (P < 0.05). Galectin-1 and CD4⁺CD25⁺Foxp3⁺ may play essential roles in maintaining a normal pregnancy and their reduction may involve in the pathogenesis of URSA.     

High CD4+ T cell density is associated with poor prognosis in patients with non-muscle-invasive bladder cancer

Purpose: The aim of this study was to investigate the clinical significance of CD4⁺ T cells in non-muscle-invasive bladder cancer (NMIBC) tissues in situ. Methods: Immunohistochemistry was used to examine the distribution of CD4⁺ T cells in 131 NMIBC tissues. Kaplan-Meier analysis and Cox proportional hazards regression models were applied to estimate overall survival (OS) and recurrence-free survival (RFS). Results: NMIBC patients were divided into two groups based on the median frequency of CD4⁺ T cells (median, 1/×400 high resolution). On univariate analysis, CD4⁺ T cell density was inversely associated with overall survival (P = 0.01). In those patients with high CD4⁺ T density, 5-year OS rates was only 77%, compared with 86% in those with low density, respectively. Although CD4⁺ T cell density showed no prognostic significance for RFS (P = 0.36), 5-year RFS rates of patients with high CD4⁺ T density (58%) was lower than those of patients with low CD4⁺ T density (65%, respectively). By multivariate analysis, tumor infiltrating CD4⁺ T cell density emerged as an independent prognostic factor for OS (HR, 2.75; P = 0.004). In addition, no association was found between CD4⁺ T cell density and any clinicopathological variables (P > 0.05). Conclusion: Our findings suggest that CD4⁺ T cells could potentially serve as a poor prognostic marker for patients with NMIBC.     

Increased chemokine receptor IL-17RA expression is associated with poor survival in gastric cancer patients

Background: Previous researchers have identified that the chemokine interleukin-17 (IL-17) was associated with survival time of patients with gastric cancer, but the roles of its receptors (IL-17R) in gastric cancer remain unknown. Our studies were designed to clarify the function of IL-17RA and to explore their potential role in gastric cancer. Materials and methods: The expression of IL-17RA was determined in primary gastric cancer tissues (n=101) using Real-time RT-PCR, immunohistochemistry, and western blotting. To investigate the functional significance of IL-17RA expression, IL-17RA expression and clinical parameters, multivariate survival was analyzed in patients with gastric cancer. Results: IL-17RA was overexpression in gastric cancer tissues compared with adjacent normal tissues (P<0.05). The elevated expression level of IL-17RA was observed correlated significantly with tumor progression (P=0.003), Lymphatic invasion (P=0.019), lymphoid nodal status (P=0.001), distant metastasis (P<0.001) of gastric cancer patients, TNM stage (P=0.0013) and was one of the independent prognostic factors for patient’s overall survival. Conclusions: These results demonstrated that the expression of IL-17RA plays an important role in gastric cancer progression, migration and prognosis of gastric cancer. The IL-17-IL-17RA signaling mechanism may be a potential novel target.     

Impact of chemokine receptor CXCR3 on tumor-infiltrating lymphocyte recruitment associated with favorable prognosis in advanced gastric cancer

Chemokine receptor CXCR3 has been proved to play an important role in tumorigenesis and tumor progression in many malignancies, but its precise efficacy on gastric cancer (GC) has not been evaluated yet. The present study was aimed to explore the correlation of chemokine receptor CXCR3 with tumor-infiltrating lymphocytes (TILs) and prognosis in advanced gastric cancer (GC). Expression of CXCR3 and CD4+, CD8+ TILs was conducted in 192 advanced GC specimens and 48 corresponding paracancerous tissues by immunohistochemical (IHC) analysis. CXCR3 expression in GC tissues was significantly higher than that in paracancerous tissues (P<0.001) and CD8+, CD4+ TILs infiltration increased with high CXCR3 expression (P=0.032 and P<0.001, respectively). Our study showed significantly lower CXCR3 expression in patients with greater tumor invasion depth and lymph node metastasis compared with patients with lesser tumor invasion depth and without lymph node metastasis (P=0.002 and P=0.001, respectively). Univariate analysis indicated that patients with high CXCR3 expression and high CD8+ TILs infiltration had longer overall survival (OS) (log-rank test, P<0.001 and P=0.002, respectively). Univariate and multivariate analyses indicated that CXCR3 expression was an independent prognostic factor for OS (P=0.002). The present study suggested that CXCR3 expression was upregulated in advanced GC and was associated with increased CD4+, CD8+ TILs infiltration and improved OS. Therefore, CXCR3 overexpression is implicated as a favorable prognostic biomarker in human advanced GC.     

The Tim-3/galectin-9 pathway involves in the homeostasis of hepatic Tregs in a mouse model of concanavalin A-induced hepatitis

T cell immunoglobulin- and mucin-domain-containing molecule-3 (Tim-3) is a negative regulator of interferon (IFN)-γ-secreting CD4⁺ Th1 cells and plays a key role in autoimmune diseases. Here, we report that galectin-9 expression was increased in hepatic CD4⁺CD25⁺ T cells in a mouse model of concanavalin A (Con A)-induced hepatitis. Moreover, Tim-3 showed increased levels in CD4⁺CD25⁺ Foxp3⁺ regulatory T cells (Tregs). Further analyses showed that blocking the Tim-3/galectin-9 pathway resulted in the suppression of Tregs in vitro, thereby significantly increasing interferon (IFN)-γ production from hepatic Teffs. Moreover, blockade of Tim-3 in vivo with an anti-Tim-3 antibody exacerbated the acute hepatitis, possibly by increased IFN-γ production. Furthermore, we found that in vitro activation of CD4⁺CD25⁻ T cells with the T cell receptor (TCR) plus interleukin 2 (IL-2) up-regulated Tim-3 expression. And the induced Tim-3 interacted with galectin-9 to induce CD4⁺ T cell apoptosis which could be partly reversed by blocking Tim-3 signaling. Our results suggested that the Tim-3/galectin-9 pathway plays a critical role in the homeostasis of hepatic Tregs through the elimination induction in Teffs and the inhibition of IFN-γ release, which contributes to the pathogenesis of liver damage and constitutes at least part of the mechanism underlying the induction of hepatitis by Con A.     

Decreased expression of SEMA3A is associated with poor prognosis in gastric carcinoma

Background/purpose: SEMA3A (semaphorin-3A), is a secreted protein that belongs to the semaphorin family and can function as both a chemoattractive agent or a chemorepulsive agent. SEMA3A has been shown to be a tumor suppressor in various cancers. This study investigated the expression of SEMA3A in gastric cancer and its prognostic value for gastric cancer patients. Methods: We examined the expression of SEMA3A in paired cancerous and matched adjacent noncancerous gastric mucosa tissues by real-time quantitative RT-PCR (qRT-PCR) and western blotting. In vitro, we evaluate the effects of SEMA3A on gastric cancer cell proliferation and migration by MTT, transwell and wound-healing assays. Furthermore, we analyzed SEMA3A expression in 128 patients who underwent resection procedures using immunohistochemistry. The relationships between the SEMA3A expression levels, the clinicopathological factors, and patient survival were investigated. Results: Our results revealed decreased SEMA3A mRNA (P = 0.0037) and protein (P = 0.033) expression in tumor tissue samples compared with matched adjacent non-tumorous tissue samples. Overexpression of SEMA3A inhibits gastric cancer cell proliferation and migration in vitro. Immunohistochemical staining data showed that SEMA3A expression was significantly decreased in 54.68% of gastric cancer cases. In addition, the chi-square test revealed that low SEMA3A expression was significantly correlated with poor differentiation (P = 0.015), Vascular invasion (P = 0.001), depth of invasion (P < 0.001), lymph node metastasis (P = 0.029), distant metastasis (P = 0.002) and advanced TNM stage (P = 0.003). SEMA3A expression was positively correlated with clinical TNM stage, that suggested the more advanced clinical TNM stage corresponding to the lower expression level of SEMA3A (r_s = -0.322, P < 0.001) by Spearman rank correlation analysis. Kaplan-Meier survival analysis demonstrated that low expression of SEMA3A was significantly correlated with a poor prognosis for gastric cancer patients (P < 0.001). The multivariate analysis revealed that SEMA3A expression was an independent prognostic factor of the overall survival rate of patients with gastric cancer. Conclusion: SEMA3A expression decreased significantly as gastric cancer progressed and metastasized, suggesting that SEMA3A might serve as a candidate tumor suppressor and a potential prognostic biomarker in gastric carcinogenesis.     

CD8+ CD28− T cells in vertically HIV-infected children

To evaluate whether vertical HIV infection interferes with the expression of CD28 on T lymphocytes, 25 HIV-infected children and 29 seroreverted children born to HIV⁺ mothers were studied. The percentage of CD28⁻ cells among CD8⁺ T lymphocytes was higher in HIV-infected children than in controls (P < 0.001). In fact, in HIV-infected children, this percentage was elevated from the first year of life, while in healthy seroreverted children, the proportion of CD28⁻ cells among CD8⁺ cells rose progressively with age (r = 0.49; P = 0.008). In HIV⁺ children, the CD8⁺ CD28⁻, but not CD8⁺ CD28⁺ cell proportion was significantly correlated with immunological markers of disease progression, such as CD4⁺ cell loss (r = −0.65; P < 0.001) and the level of in vitro spontaneous lymphocyte apoptosis (r = 0.53; P = 0.03).     

Cytolytic mechanisms and T-cell receptor Vβ usage by ex vivo generated Epstein–Barr virus-specific cytotoxic T lymphocytes

Ex-vivo-generated Epstein–Barr virus (EBV)-specific cytotoxic T lymphocytes (CTL) have been used for cellular adoptive immunotherapy of EBV-associated lymphomas. Here we investigated the phenotypes, cytolytic mechanisms, polyfunctionality and T-cell receptor (TCR) usage in growing and established CTL, generated by weekly stimulation with an EBV-transformed autologous lymphoblastoid cell line (LCL). Our results showed that phenotypically mature CTL developed within the first 4 weeks of culture, with an increase in CD45RO and CD69, and a decrease in CD45RA, CD62L, CD27 and CD28 expression. Spectratyping analysis of the variable β-chain of the TCR revealed that TCR repertoire remained diverse during the course of culture. Cytotoxicity of CTL was significantly inhibited by concanamycin A (P < 0·0001) and ethylene glycol-bis tetraacetic acid (P < 0·0001), indicating that a calcium and perforin-mediated exocytosis pathway with the release of granzyme B was the principal cytotoxic mechanism. The CTL mainly produced interferon-γ (IFN-γ) or tumour necrosis factor-α (TNF-α) upon restimulation with autologous LCL, although there were some polyfunctional cells producing IFN-γ and TNF-α. Granzyme B, perforin and Fas ligand were detected in CD8⁺ and CD4⁺ cells in all CTL; however, a greater proportion of CD8⁺ than CD4⁺ T cells expressed granzyme B (P < 0·0001) and more granzyme B was detected in CD8⁺ T cells than in CD4⁺ T cells (P = 0·001). This difference was not observed with Fas ligand or perforin expression. Our results provide insight into the basic characteristics of ex-vivo-generated CTL.     

IMP3 expression in biopsy specimens of colorectal cancer predicts lymph node metastasis and TNM stage

IMP3 is associated with lymph node metastasis and TNM stage and is a good independent prognostic biomarker for colorectal cancer (CRC). However, the expression status and clinical implication of IMP3 in biopsy specimens have not yet been studied. We aim to address whether the presence of IMP3 expression in preoperative biopsies of CRC could predict lymph node metastasis and TNM stage. In this study, we examined IMP3 expression in paired biopsy and resection specimens of 71 CRC and analyzed the correlation of IMP3 expression with clinicopathological parameters. In the biopsy specimens, IMP3 positive expression was observed in 56 of 71 cases (78.9%) whereas negative expression was observed in 15 of 71 cases (21.1%). In the resection specimens, IMP3 positive expression was detected in 83.1% cases (59/71) whereas negative expression was detected in 16.9% cases (12/71). The absolute concordance rate between biopsy and resection specimens was 90.1% (64/71). The Spearman correlation test documented the existence of a strong linear correlation between the percentage of IMP3-positive cells in the biopsy and resection specimen (r = 0.629; P < 0.001). IMP3 expression in resection specimens was significantly related to histological grade (P = 0.043), T classification (P = 0.035), lymph node metastasis (P = 0.023), TNM stage (P = 0.007), tumor border (P = 0.049) and tumor budding (P = 0.012). IMP3 expression in biopsy specimens was significantly related to lymph node metastasis (P = 0.004), TNM stage (P = 0.005) and tumor budding (P = 0.001). In conclusion, IMP3 expression in biopsy specimens could be used to predict lymph node metastasis and TNM stage in CRC patients.     

Increased numbers of CD5+ B cells and T cell receptor (TCR) γδ+ T cells are associated with younger age of onset in rheumatoid arthritis (RA)

Patients presenting with RA before the age of 45 years (younger onset) are known to have more aggressive disease compared with patients presenting after the age of 65 years (older onset). Coordinated expansion of circulating CD5⁺ B cell and TCR γδ⁺ T cell levels has been reported in patients with RA. This study assesses the peripheral blood levels of these two cell types in RA patients with younger and older onset of disease. CD5⁺ B cell levels were significantly elevated in the younger onset RA group (26·6 ± 4·5%) compared with the older onset RA group (14·2 ± 1·2%; P <0·01). TCR γδ⁺ T cell levels were also significantly raised in the young patients (4·0 ± 0·9%) compared with elderly patients (1·6 ± 0·2%; P <0·01). T cell levels (CD3⁺) were similar in both groups (young 66·4 ± 3·3%; old 74·3 ± 3·4% (mean ± s.e.m.); NS). Total B cell levels (CD19⁺) were also similar in these groups (7·7 ± 0·7% versus 8·9 ± 1·8%; NS). A significant positive correlation was observed between the CD5⁻ B and TCR γδ⁺ T cell types in the patients (r = 0·72, P <0.05). Compared with age-matched normal controls, the younger onset patients had similar CD5⁺ B cell and TCR γδ⁺ T cell levels to the elderly controls (CD5⁺ B cells 30·2 ± 3·0%; TCR γδ⁺ T cells 3·0 ± 0·8%). Conversely, older onset RA patients had CD5⁺ B cell levels similar to the young controls (12·3 ± 1·9%). Spontaneous in vitro synthesis of immunoglobulins (IgM, IgA and IgG) and rheumatoid factors (IgM and IgA isotypes) were not significantly different in both patient groups. The coordinate expansion of circulating CD5⁺ B cells and γδ⁺ T cells seen in patients with RA presenting before 45 years of age and not after 65 years of age may suggest a potential role for these cells in more aggressive disease states.