Review article: molecular signals and genetic reprogramming in peripheral T-cell differentiation

Differential Analysis and Putative Roles of Genes, Cytokines and Apoptotic Proteins in Blood Samples of Patients with Respiratory Viral Infections: A Single Center Study

Insights into the molecular pathogenesis of respiratory viral infections were investigated using serum and peripheral blood from patients with clinical syndromes. Signatures of expression of cytokines, genes and apoptotic proteins that discriminate symptomatic individuals from healthy individuals were determined among 21 patients. In symptomatic patients, significant upregulation of IL-1β, IL-2, IL-4, IL-6, IL-8, IL-12, IL-15, TNF-a and IFN-g (P<0.05) was noted, while IL-10 was significantly downregulated (P<0.05). This is accompanied by either up or down-regulation of various pro-apoptotic and anti-apoptotic markers, suggesting a protective role of immune responses against viral infection and the capacity of viruses to subvert host cell apoptosis. Gene expression analysis for both T and B cells were categorized according to their functional status of activation, proliferation, and differentiation. Of note, genes SH2D1A and TCL1A were upregulated only in rhinovirus samples, while PSMB7, CD4, CD8A, HLA-DMA, HLA-DRA and CD69 were upregulated in samples of Flu A and RSV but were not significant in samples of rhinovirus as compared to healthy individuals. These results demonstrated Flu A and RSV elicit different alterations in human peripheral blood gene expression as compared to rhinovirus. Overall, despite the small number of study subjects, the current study for the first time has recognized signature genes, cytokines and proteins that are used by some respiratory viruses that may serve as candidates for rapid diagnosis as well as targets for therapeutic interventions.

Urinary biomarkers in lupus nephritis

Systemic lupus erythematosus (SLE) is the prototypical autoimmune disease that can affect any organ of the body. Multiple mechanisms may contribute to the pathophysiology of systemic lupus, including failure to remove apoptotic bodies, hyperactivity of self-reactive B and T lymphocytes, abnormal exposure to autoantigens, and increased levels of B-cell stimulatory cytokines. The involvement of the kidney, called lupus nephritis (LN), during the course of the disease affects between 30% and 60% of adult SLE patients, and up to 70% of children. LN is an immune-mediated glomerulonephritis that is a common and serious finding in patients with SLE. Nowadays, renal biopsy is considered the gold standard for classifying LN, besides its degree of activity or chronicity. Nevertheless, renal biopsy lacks the ability to predict which patients will respond to immunosuppressive therapy and is a costly and risky procedure that is not practical in the monitoring of LN because serial repetitions would be necessary. Consequently, many serum and urinary biomarkers have been studied in SLE patients for the complementary study of LN, existing conventional biomarkers like proteinuria, protein/creatinine ratio in spot urine, 24 ​h urine proteinuria, creatinine clearance, among others and non-conventional biomarkers, like Monocyte chemoattractant protein-1 (MCP-1), have been correlated with the histological findings of the different types of LN. In this article, we review the advances in lupus nephritis urinary biomarkers. Such markers ideally should be capable of predicting early sub-clinical flares and could be used to follow response to therapy. In addition, some of these markers have been found to be involved in the pathogenesis of lupus nephritis.

Expression of Th1 and Th2 Cytokine and Associated Transcription Factors in Peripheral Blood Mononuclear Cells and Correlation with Disease Severity

BACKGROUND

Psoriasis is a T cell-mediated autoimmune disease in patients with elevated levels of proinflammatory cytokines belonging mainly to the Th1 pathway. We investigated whether treatment of psoriasis patients with methotrexate (MTX), along with micronutrients, modulated mRNA expression of Th1 and Th2 components and whether expression of these components correlated with psoriasis severity.

METHODS

Thirty plaque-type psoriasis patients with Psoriasis Area and Severity Index (PASI) scores greater than 10 were recruited; these were 15 non-micronutrients taking- (NMT) patients treated with MTX daily (0.2-0.3 mg/kg/week), and 15 micronutrients taking- (MT) patients treated with MTX plus a micronutrient supplement daily, for 12 weeks. Blood samples were collected immediately before treatment (baseline) and after 12 weeks of treatment. Taqman quantitative real-time polymerase chain reaction (qPCR) was applied to analyze the expression of the Th1 components T-bet, interleukin-12 (IL-12), and interferon-gamma (IFN-Υ), and the Th2 components GATA-3 and interleukin-4 (IL-4). Disease severity was measured using the PASI scoring system.

RESULTS

Significant clinical improvement in the MT group coincided with significant down-regulation of Th1 and up-regulation of Th2 markers (P<0.05). With respect to the PASI-75, (defined as a 75% or greater reduction in the PASI score) cut-off point, expression of IFN-γ in the MT group with PASI scores above 75 was significantly less than that of patients in the NMT group (P=0.05). Also, GATA3 and IL-4 mRNA expression in the MT group with PASI scores greater than above 75 was significantly greater than that of patients in the NMT group (P=0.05 and 0.04, respectively).

CONCLUSION

Based on significant attenuation of the PASI score, which correlated with upregulation of Th2 pathway markers in the MT group, we recommend administration of micronutrients combined with MTX for psoriasis patients. Our results contribute to a better understanding of methotrexate immunepathogenesis mechanisms and their correlations to clinical responses in psoriasis.

Trichloroethylene-induced hypersensitivity dermatitis was associated with hepatic metabolic enzyme genes and immune-related genes

Trichloroethylene (TCE) is one of the common organic solvents that has been widely used in cleaning or degreasing of metal and electronic products. However, hundreds of cases of hypersensitivity dermatitis have occurred after the workers were occupationally exposed to TCE in China over the past decade. The purpose of this study was to investigate mRNA expression of hepatic metabolic enzyme genes, immune-related genes, apoptosis genes and oncogenes in patients with hypersensitivity dermatitis induced by trichloroethylene. 12 typical patients with TCE-induced hypersensitivity dermatitis were investigated as the study cases, peripheral blood samples were taken from patients and control, and real-time fluorescence PCR assay was applied for detection of mRNA expression of hepatic metabolic enzyme genes, immune-related genes, apoptosis genes and oncogenes. It was found that the relative levels of mRNA expression of CYP1A2, CYP2E1, CYP3A4 and CYP2C9 increased by 723%, 318%, 385% and 216%, respectively, when compared with control (p < 0.01 or p < 0.05); Foxp3, GATA3 and CTLA4 mRNA expression increased by 104%, 106% and 253%, respectively, in TCE patients when compared with control (p < 0.01); T-bet expression decreased by 44% when compared with control (p < 0.01); these findings indicate that some immune-related genes and hepatic metabolic enzyme genes might play an important role in the process of trichloroethylene-induced hypersensitivity dermatitis.

Increased CD1c+ mDC1 with mature phenotype regulated by TNFα-p38 MAPK in autoimmune ocular inflammatory disease

In this study we investigated the role of blood CD1c(+) myeloid dendritic cells 1 (mDC1), a key mDC subtype, in patients with autoimmune uveitis. We observed a significant increase of blood CD1c(+) mDC1 in uveitis patients. The increased CD1c(+) mDC1 exhibited high HLADR expression and less antigen uptake. CD1c(+) mDC1 were divided into two subpopulations. CD1c(hi) mDC1 subpopulation showed less antigen uptake and higher HLADR expression compared to CD1c(lo) mDC1 subpopulation. Importantly, the CD1c(hi) mDC1 subpopulation was increased in uveitis patients. In vitro, mature monocyte-derived dendritic cells (MoDCs), characterized by lower levels of antigen uptake, induced more CD4(+)CD62L(-) T helper cell proliferation. The mature phenotype and function of CD1c(+) mDC1 were regulated by TNFα via a p38 MAPK-dependent pathway. These data show that alterations in the systemic immune response are involved in the pathogenesis of autoimmune uveitis and invite the therapeutic possibility of attenuating uveitis by manipulating blood CD1c(+) mDC1.

The diagnostic value of transcription factors T-bet/GATA3 ratio in predicting antibody-mediated rejection

Background. Previous data showed that the predominance of intraglomerular T-bet or GATA3 is correlated with different mechanisms of rejection, suggesting that the ratio of T-bet/GATA3 might be used to distinguish antibody-mediated rejection (ABMR) and T-cell-mediated rejection (TCMR). Methods. We compared the intraglomerular T-bet/GATA3 ratio in ABMR and TCMR. The intragraft expression of T-bet and GATA3 was studied via immunohistochemistry. The correlation of the diagnosis of AMR with the ratio of T-bet/GATA3 was examined. Results. Both intraglomerular T-bet- and GATA3-expressing cells were increased during acute rejection. T-bet/GATA3>1 was strongly correlated with ABMR (93.3% versus 18.2%). The incidence of positive HLA-I/II antibodies and glomerulitis is significantly higher in T-bet/GATA3>1 group (P < 0.001, 0.013, resp.). The scores of peritubular capillary inflammation and glomerulitis were also higher in T-bet/GATA3>1 group (P = 0.052, P < 0.001, resp.). Nevertheless, T-bet/GATA3>1 is also correlated with C4d-negative ABMR and resistance to steroid treatment. Compared with C4d deposition, T-bet/GATA3>1 had a slight lower (90% versus 100%) specificity but a much higher (87.5% versus 68.8%) sensitivity. Conclusion. Our data suggested that intraglomerular predominance of T-bet over GATA3 might be used as diagnosis maker of ABMR in addition to C4d, especially in C4d-negative cases.

Increased memory Th17 cells in patients with neuromyelitis optica and multiple sclerosis

OBJECT

To investigate the clinical relevance of memory Th17 cells in patients with neuromyelitis optica (NMO) or multiple sclerosis (MS).

PATIENTS AND METHODS

The proportion of peripheral memory Th17 cells was determined by flow cytometry. Sera IL-17A and IL-23 levels were detected by ELISA kits.

RESULTS

Memory Th17 proportion and IL-17A level were much higher in patients with NMO or MS and were related to clinical features. After high-dose intravenous methylprednisolone (IVMP) therapy, memory Th17 proportion and IL-17A and IL-23 levels were decreased.

CONCLUSIONS

Memory Th17 is related to the development and relapse of NMO and MS, and IVMP can inhibit memory Th17.

Predominance of intraglomerular T-bet or GATA3 may determine mechanism of transplant rejection

The transcription factors T-bet and GATA3 determine the differentiation of helper T cells into Th1 or Th2 cells, respectively. An altered ratio of their relative expression promotes the pathogenesis of certain immunological diseases, but whether this may also contribute to the pathogenesis of antibody-mediated rejection (ABMR) versus T cell-mediated rejection (TCMR) is unknown. Here, we characterized the intragraft expression of T-bet and GATA3 and determined the correlation of their levels with the presence of typical lesions of ABMR and TCMR. We found a predominant intraglomerular expression of T-bet in patients with ABMR, which was distinct from that in patients with TCMR. In ABMR, interstitial T-bet expression was typically located in peritubular capillaries, although the overall quantity of interstitial T-bet was less than that observed in TCMR. The expression of intraglomerular T-bet correlated with infiltration of CD4+ and CD8+ lymphocytes, which express T-bet, as well as intraglomerular CD68+ monocyte/macrophages, which do not express T-bet. The predominance of intraglomerular T-bet expression relative to GATA3 expression associated with poor response to treatment with bolus steroid. In summary, predominance of intraglomerular T-bet expression correlates with antibody-mediated rejection and resistance to steroid treatment.

The promise of 4-1BB (CD137)-mediated immunomodulation and the immunotherapy of cancer

The continuing efforts in biomedical research to develop new therapies for cancer are entering an exciting new phase. Research over the past two to three decades has yielded a much more detailed understanding of the complexities of the cellular and molecular interactions involved in the generation and regulation of immune responses. We are also gaining insights into the mechanisms by which tumors evade or escape immune recognition and by which they become resistant to various existing chemotherapeutic and/or radiotherapeutic strategies. A clear conclusion that can be drawn from these studies is that effective treatments of cancer will become much more multifaceted and will include immunotherapeutic approaches. The identification and molecular cloning of genes encoding the receptors and ligands that play crucial roles in the generation and regulation of immune responses provides exciting new opportunities to induce and enhance effective endogenous immune responses to cancer. In this regard, the genes that comprise the tumor necrosis factor and tumor necrosis factor receptor superfamilies show particular promise. One receptor:ligand pair (4-1BB/CD137 and 4-1BBL/CD137L) is emerging as a target with important potential in its ability to enhance the generation of effective tumor-specific immune responses in situ. The results of the studies cited in this review highlight the potentials of 4-1BB-mediated immunotherapy.

Imbalance of Th1/Th2 transcription factors in patients with lupus nephritis

OBJECTIVE

Systemic lupus erythematosus (SLE) is characterized by the aberrant activation of T lymphocytes. Since T-bet and GATA-3 are the principal transcription factors for the differentiation of type-1 and type-2 helper T lymphocytes, respectively, we studied their mRNA expression in the urinary sediment of SLE patients and compared this with their urinary and intra-renal protein expression.

METHODS

We studied 100 SLE patients and 10 healthy subjects. Urinary mRNA expression of T-bet and GATA-3 were studied by the real-time quantitative polymerase chain reaction. Intra-renal and urinary expressions of T-bet and GATA-3 were studied by immunohistochemistry and western blotting, respectively.

RESULTS

The urinary mRNA and protein expressions of T-bet were significantly higher in SLE patients with active nephritis than those with inactive disease (mRNA: P < 0.001; protein: P = 0.004). The urinary mRNA expression of T-bet correlated with the SLE disease activity index (SLEDAI) score (r = 0.55, P < 0.001) and the histological activity index (r = 0.48, P = 0.03). On the other hand, the urinary mRNA and protein expressions of GATA-3 were significantly lower in SLE patients with active nephritis (mRNA: P < 0.001; protein: P = 0.006), and GATA-3 mRNA expression inversely correlated with the SLEDAI score (r = 0.38, P < 0.001). For the 22 SLE patients with kidney biopsy, tubular expressions of T-bet and GATA-3 significantly correlated with the histological activity index (T-bet: r = 0.57, P = 0.006; GATA-3: r = -0.79, P < 0.001).

CONCLUSIONS

Patients with active lupus nephritis have increased T-bet and depressed GATA-3 expression in the urinary sediment and kidney tissue, indicating a predominant Th1 type of T-lymphocyte activation.

Advances in the clinical laboratory assessment of urinary sediment

Urinalysis has been used extensively in clinical practice to aid in the diagnosis of various renal and urologic diseases. The innovation of urinalysis is marching on right along with the rapid developments in biotechnology and astride from the solo urine cytology to sophisticated studies of individual component in the urinary sediment. In this review article, we focus on the use of flow cytometry and other technical advances in the examination of urinary sediment, the detection of urologic malignancies by the presence of microsatellite alteration in the urinary sediment, as well as the quantification of cytokine messenger RNA (mRNA) expression in urinary sediment by reverse transcription and real-time quantitative polymerase chain reaction (RT-QPCR). Notably, the study of cytokine mRNA expression in urinary sediment by RT-QPCR has recently been reported to provide important diagnostic information in kidney allograft recipients and patients with lupus nephritis. This simple and non-invasive method requires further study to determine its role in risk stratification and monitoring of therapeutic response in patients with other kidney diseases.

HLA-DRB1 allele polymorphisms in genetic susceptibility to esophageal carcinoma

AIM: To probe into the genetic susceptibility of HLA-DRB1 alleles to esophageal carcinoma in Han Chinese in Hubei Province.

METHODS: HLA-DRB1 allele polymorphisms were typed by polymerase chain reaction with sequence-specific primers (PCR-SSP) in 42 unrelated patients with esophageal cancer and 136 unrelated normal control subjects and the associated HLA-DRB1 allele was measured by nucleotide sequence analysis with PCR.SAS software was used in statistics.

RESULTS: Allele frequency (AF) of HLA-DRB1*0901 was significantly higher in esophageal carcinoma patients than that in the normal controls (0.2500 vs 0.1397, P = 0.028, the odds ratio 2.053, etiologic fraction 0.1282). After analyzed the allele nucleotide sequence of HLA-DRB1*0901 which approachs to the corresponded exon 2 sequence of the allele in genebank. There was no association between patients and controls in the rested HLA-DRB1 alleles.

CONCLUSION: HLA-DRB1*0901 allele is more common in the patients with esophageal carcinoma than in the healthy controls, which is positively associated with the patients of Hubei Han Chinese. Individuals carrying HLA-DRB1*0901 may be susceptible to esophageal carcinoma.

Modulation of T cell cytokine production by interferon regulatory factor-4

Production of cytokines is one of the major mechanisms employed by CD4(+) T cells to coordinate immune responses. Although the molecular mechanisms controlling T cell cytokine production have been extensively studied, the factors that endow T cells with their ability to produce unique sets of cytokines have not been fully characterized. Interferon regulatory factor (IRF)-4 is a lymphoid-restricted member of the interferon regulatory factor family of transcriptional regulators, whose deficiency leads to a profound impairment in the ability of mature CD4(+) T cells to produce cytokines. In these studies, we have investigated the mechanisms employed by IRF-4 to control cytokine synthesis. We demonstrate that stable expression of IRF-4 in Jurkat T cells not only leads to a strong enhancement in the synthesis of interleukin (IL)-2, but also enables these cells to start producing considerable amounts of IL-4, IL-10, and IL-13. Transient transfection assays indicate that IRF-4 can transactivate luciferase reporter constructs driven by either the human IL-2 or the human IL-4 promoter. A detailed analysis of the effects of IRF-4 on the IL-4 promoter reveals that IRF-4 binds to a site adjacent to a functionally important NFAT binding element and that IRF-4 cooperates with NFATc1. These studies thus support the notion that IRF-4 represents one of the lymphoid-specific components that control the ability of T lymphocytes to produce a distinctive array of cytokines.

4-1BB-specific monoclonal antibody promotes the generation of tumor-specific immune responses by direct activation of CD8 T cells in a CD40-dependent manner

4-1BB (CD137) is a member of the TNFR superfamily (TNFRSF9). T cell expression of 4-1BB is restricted to activated cells, and cross-linking has been shown to deliver a costimulatory signal. Here we have shown that treatment of tumor-bearing mice with agonistic 4-1BB-specific Abs can lead to T cell-mediated tumor rejection. In vivo mAb depletion experiments demonstrated that this rejection requires CD8(+) cells but not CD4(+) or NK cells. Both IFN-gamma- and CD40-mediated signals were also required, because no benefit was observed on treatment with 4-1BB mAb in mice in which the genes for these molecules had been knocked out. Interestingly, 4-1BB-mediated stimulation of immune responses in CD40L(-/-) mice is effective (although at a reduced level), and may suggest the existence of an alternative ligand for CD40. Additional experiments in IL-15(-/-) mice indicate that IL-15 is not required for either the generation of the primary tumor-specific immune response or the maintenance of the memory immune response. In contrast, the presence of CD4 cells during the primary immune response appears to play a significant role in the maintenance of effective antitumor memory. Finally, in mice in which the number of dendritic cells had been expanded by Fms-like tyrosine kinase3 ligand treatment, the antitumor effects of 4-1BB ligation were enhanced.

The kinetics of in vivo priming of CD4 and CD8 T cells by dendritic/tumor fusion cells in MUC1-transgenic mice

Previous work has demonstrated that dendritic/tumor fusion cells induce potent antitumor immune responses in vivo and in vitro. However, little is known about the migration and homing of fusion cells after s.c. injection or the kinetics of CD4+ and CD8+ T cell activation. In the present study, fluorescence-labeled dendritic/MUC1-positive tumor fusion cells (FC/MUC1) were injected s.c. into MUC1-transgenic mice. The FC/MUC1 migrated to draining lymph nodes and were closely associated with T cells in a pattern comparable with that of unfused dendritic cells. Immunization of MUC1-transgenic mice with FC/MUC1 resulted in proliferation of T cells and induced MUC1-specific CD8+ CTL. Moreover, CD4+ T cells activated by FC/MUC1 were multifunctional effectors that produced IL-2, IFN-gamma, IL-4, and IL-10. These findings indicate that both CD4+ and CD8+ T cells can be primed in vivo by FC/MUC1 immunization.

Defective T cell activation and autoimmune disorder in Stra13-deficient mice

Stra13, a basic helix-loop-helix transcription factor, is up-regulated upon activation of CD4+ T cells. Here we show that Stra13-deficient mice exhibit defects in several phases of CD4+ T cell activation. In vivo, Stra13 deficiency results in ineffective elimination of activated T and B cells, which accumulate progressively, leading to lymphoid organ hyperplasia. Consequently, aging Stra13-/- mice develop autoimmune disease characterized by accumulation of spontaneously activated T and B cells, circulating autoantibodies, infiltration of T and B lymphocytes in several organs and immune complex deposition in glomeruli. Our studies identify Stra13 as a key regulator of lymphocyte activation that is vital for maintenance of self-tolerance and for constraint of autoimmunity.