Pimpayao Sodsai

Decreased renal expression of vascular endothelial growth factor in lupus nephritis is associated with worse prognosis

Recent studies suggest that vascular endothelial growth factor (VEGF) plays a crucial role in the preservation of renal function and may also serve as a useful biomarker in monitoring the progression of lupus nephritis (LN). Here we sought to correlate intrarenal VEGF expression with renal histopathology and prognosis of LN. Biopsy specimens from 35 patients with Class III or IV LN (ISN/RPS categorization) were found to have lower levels of intrarenal VEGF than those found in biopsy tissue taken from 10 donor kidneys sampled at the time of allograft reperfusion. This reduced amount of VEGF mRNA in the patients with LN negatively correlated with glomerular endocapillary proliferation, crescent formation, and a high histologic activity index but was positively associated with increased numbers of urinary podocytes. The level of intrarenal VEGF mRNA accurately predicted the deterioration of renal function in these patients within 12 months. Our study shows that expression of VEGF in renal tissue may serve as a molecular marker of renal damage and may be a predictive factor for short-term loss of kidney function in patients with LN.

Association of interferon-gamma gene polymorphism (+874A) with arthritis manifestation in SLE

Systemic lupus erythematosus (SLE) is a complex autoimmune disease in which genetic factors strongly influence susceptibility. Cytokines such as the interferon-gamma (IFNG) gene play a key role in controlling the immunity and inflammation, and therefore their polymorphisms may affect these genes’ expression levels among individuals. We investigated the frequency of IFNG gene intron (+874) polymorphism, previously reported to be associated with IFNG production, in SLE patients compared to a control group. This population-based case–control study includes 154 SLE patients and 154 healthy control subjects with similar ethnic backgrounds. The genotyping was determined by polymerase chain reaction sequence-specific primer method and using the Chi-squared test for analyzing the association between this single-nucleotide polymorphism and SLE. The allele frequencies of the IFNG (+874) gene polymorphism were not significantly different between SLE patients and control subjects (72.7 vs 77%). However, there was a significant association between A dominance model of inheritance with arthritis (odds ratio = 7.64, 95% confidence interval = 1.56–41.64, P = 0.006, Pc = 0.03). The result suggested that the +874 intron polymorphism of IFNG can be used as the marker for SLE susceptibility with arthritis in the Thai population.

Defects in Notch1 upregulation upon activation of T Cells from patients with systemic lupus erythematosus are related to lupus disease activity

Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by the production of autoantibodies and deposition of immune complexes in various organs. T cells play a central role in driving disease progression, and multiple defects in T cells from patients with SLE have been uncovered. Notch signalling is an evolutionarily well-conserved signalling cascade involved in the proliferation, differentiation and apoptosis of T lymphocytes during development and peripheral effector functions. In this study, we investigated the correlation between expression of Notch receptor and the severity of SLE disease. On the contrary to T lymphocytes from healthy controls (n = 11), Tlymphocytes from patients with active SLE (n = 12) failed to upregulate Notch1 upon in-vitro stimulation as quantified by quantitative real time RT-PCR (P ≤ 0.025). Among patients with inactive SLE (n = 10), those with late onset of flare exhibited significantly less Notch1 upregulation compared with SLE patients with remission. Expression of the Notch target genes, Hes1 and deltex, was also lower in patients with active SLE. The decrease in Notch1 mRNA expression was consistent with less Notch1 protein expression in patients with active SLE. The defects in Notch1 upregulation correlated with decreased proliferation, CD25 and Foxp3 expression upon stimulation in vitro. Taken together, the failure of T cells to upregulate Notch1 upon activation may be a key feature of active SLE and a potential therapeutic target.

Increased interleukin-23 receptor+T cells in peripheral blood mononuclear cells of patients with systemic lupus erythematosus

IntroductionSystemic lupus erythematosus (SLE) is an autoimmune disorder characterized by production of autoantibodies and immune complex deposition in various organs. Aberrations in the T lymphocyte compartment and dysregulated cytokine production are key features of SLE pathogenesis and disease progression. Recently, the role of the interleukin (IL)-17/IL-23 axis in the pathogenesis of SLE has been reported. IL-23 and IL-23R are essential for expansion of pathogenic IL-17-producing T lymphocytes and have been shown to be important in the pathogenesis of lupus in animal models.MethodsIn this study, the expression of IL-23R and IL-17 in CD4+ and CD8+ T lymphocytes in peripheral blood mononuclear cells (PBMCs) of SLE patients and control subjects were examined by flow cytometry. Twenty-nine SLE patients and 10 control subjects were recruited in this study. Patients were divided into active and inactive groups based on the SLE disease activity index (SLEDAI). As another disease control population, five psoriatic patients were recruited in this study.ResultsPercentages of both IL23R+ CD4+ and IL-23R+ CD8+ T cell subsets were significantly higher in freshly isolated PBMCs from both groups of SLE patients compared to control subjects (P = 0.0021 and P = 0.0006, respectively). In addition, this difference was maintained after ex vivo stimulation with plate-bound anti-CD3/CD28 antibodies (P = 0.007 and P = 0.0019, respectively). When the fold increase in IL-17+ T cells after ex vivo stimulation for three days was compared between patients and controls, SLE patients exhibited significantly higher increases in CD4+ IL-17+ and CD8+ IL-17+ T cells, suggesting that PBMCs from SLE patients promoted the expansion of IL-17-producing T cells upon stimulation more vigorously than control PBMCs. These trends were not observed in psoriasis patients. The correlations between IL-23R+ T cells and IL-17+ T cells and IL-23R+ CD8+ T cells and SLEDAI scores in patients were also found to be statistically significant.ConclusionsThe results of our study confirmed the relevance of the IL-23/IL-17 axis in the pathogenesis of SLE and further highlighted the importance of IL-23R+ T cell subsets in this autoimmune disease.

Association of interferon-gamma gene polymorphisms with susceptibility to oral lichen planus in the Thai population

OBJECTIVE Interferon-gamma (IFN-γ) is highly expressed in oral lichen planus (OLP). The IFN-γ (+874 in intron 1, rs2430561) TT genotype, which has been reported to be associated with high IFN-γ production, was hypothesized to be associated with susceptibility to OLP in the Thai population. DESIGN Genomic DNA samples from 74 OLP and 268 healthy controls were evaluated for IFN-γ polymorphisms by polymerase chain reaction with sequence-specific primers (PCR-SSP) and direct sequencing method. RESULTS The T allele was significantly associated with an increased risk of OLP development as compared to the A allele (OR=1.76, P=0.004; P(c)=0.02). The effect of the T allele was similar to an autosomal recessive disorder; the presence of TT genotype (when compared to AA and AT) conferred an OR of 2.61, P=0.008; P(c)=0.04. CONCLUSIONS We found an association between IFN-γ +874A/T polymorphism and susceptibility to OLP. However, an association study utilising a larger sample size and patients from other races apart from the Asian population should be performed to further verify these findings.

Immunoprevalence and Immunodominance of HLA-Cw∗0801-Restricted T Cell Response Targeting the Hepatitis B Virus Envelope Transmembrane Region

ABSTRACT HLA-C-restricted T cells have been shown to play an important role in HIV control, but their impact on protection or pathogenesis in other viral infections remains elusive. Here, we characterized the hierarchy of HLA class I-restricted hepatitis B virus (HBV) epitopes targeted by CD8 T cells in HBV-infected subjects. The frequency of CD8 T cells specific for a panel of 18 HBV epitopes (restricted by HLA-A∗0201/03/07 [hereinafter HLA-A0201/03/07], -A1101, -A2402/07, -B5801, -B4001, -B1301, and -Cw0801) was quantified in a total of 59 subjects who resolved HBV infection. We found that the HLA-Cw0801-restricted epitope comprised of Env residues 171 to 180 (Env171–180) is immunoprevalent in the Southeast Asian subjects (10/17 HLA-Cw0801-positive subjects) and immunodominant in the majority of HLA-Cw0801-positive subjects able to control HBV infection. HLA-Cw0801-restricted Env171–180-specific CD8 T cells recognized endogenously produced HBV surface antigen (HBsAg) and tolerated amino acid variations within the epitope detected in HBV genotypes B and C. In conclusion, we demonstrate that the HLA-Cw0801-restricted Env171–180 T cell response is an important component of the HBV-specific adaptive T cell immunity in Asians infected with HBV. Thus, HLA-C restricted T cells might play an important role in various viral infections.

Association of cytokine and cytokine receptor gene polymorphisms with the risk of chronic hepatitis B.

BACKGROUND Hepatitis B (HBV) infection is a major cause of chronic liver diseases, and the polymorphisms of cytokine genes may affect the progression of HBV-related hepatitis. OBJECTIVE The aim of this study was to examine the association of cytokine polymorphisms with the susceptibility to HBV-related chronicity. METHODS Specifically, a LIFECODES Cytokine SNP Typing kit was used to investigate 22 cytokine single nucleotide polymorphisms (SNPs) from 14 cytokine and cytokine receptor genes with the aim of analyzing the role of Th1 and Th2 genotype combination. This population-based case-control association study included 131 chronic HBV patients and a control group of 142 healthy donors. RESULTS When the combination of Th1 and Th2 genotypes was analyzed for the genetic risk factor for chronic hepatitis B, we did not observe any significant association. A non-significant association betweenTh1 and Th2 and this risk factor could have resulted from the limitation of our small sample size. When the results from each genotype were separately analyzed, the frequencies of the heterozygous CA (-592) and CT (-819) genotype of IL-10 gene-promoter polymorphisms were significantly higher in chronic HBV patients than that in healthy controls (OR=1.76, 9%CI =1.03-3.01, p =0.028; OR=1.79, 95%CI =1.04-3.06, p =0.024, respectively). Interestingly, the TCC (-1098/-590/-33) haplotype frequency of IL-4 showed a positive association with chronic hepatitis B as a protective haplotype (OR =0.53, 95%CI =0.32-0.85, p =0.005). CONCLUSION These preliminary results suggest that polymorphisms in some cytokine genes, particularly the Th2 cytokine, influence persistence of HBV infection.

Distribution of cytokine gene polymorphisms in Thai population

The distribution of 21 cytokine polymorphisms within 13 cytokine and cytokine receptor genes was analyzed in 102 healthy Thai individuals using the LIFECODES Cytokine SNP Typing kit. The TGFB codon25 marker is monomorphic in the Thai population. The IL1B+3962, IL6-174, and TNFA-238 are very rare polymorphisms, with only 0.01-0.04 minor allele frequency (MAF). The IL4-1098, IL1A-889, and IL10-1082 are found only 0.06-0.08 in Thai. Other cytokine polymorphisms (IL1B-511, IL1R pst1 1970, IL1RN mspa1 11100, IL4RA+1902, IL12B-1188, IFNG+874, TGFB codon10, TNFA-308, IL2-330, IL2+166, IL4-590, IL4-33, IL10-819, and IL10-592) in Thai have MAFs more than 0.10, ranging between 0.13 and 0.47. When comparing the allele and genotype frequencies with public single nucleotide polymorphism (SNP) database, most cytokine polymorphisms in Thai show similar distribution to Han Chinese and Japanese, but significantly different from Caucasian and African populations. Only a few markers, including IL4A+1902, TNFA-308, IL1B+3962, and IL2+166 show statistically different distribution among Thai and other Asian populations especially with the Japanese.

Slow desensitization of imatinib-induced nonimmediate reactions and dynamic changes of drug-specific CD4+CD25+CD134+ lymphocytes

BACKGROUND Imatinib is a tyrosine kinase inhibitor indicated for the treatment of gastrointestinal stromal tumors (GISTs) and certain neoplastic diseases; however, nonimmediate adverse reactions are common. OBJECTIVE To describe the process of imatinib slow desensitization in patients who experienced nonimmediate reactions to imatinib and the dynamic change in drug-specific CD4+CD25+CD134+ T-lymphocyte percentages. METHODS Five patients diagnosed as having GISTs and with a recent history of imatinib-induced nonimmediate reactions (maculopapular exanthema with eosinophilia, exfoliative dermatitis, palmar-plantar erythrodysesthesia, and drug rash with eosinophilia and systemic symptoms) were desensitized using a slow desensitization protocol. The reintroduced imatinib dosage was stepped up every week starting from 10 mg/d and increasing to 25, 50, 75, 100, 150, 200, and 300 mg/d until the target dose of 400 mg/d was achieved. Prednisolone of up to 30 mg/d was allowed if allergic reactions recurred. The percentages of CD4+CD25+CD134+ T cells present after incubating peripheral blood mononuclear cells with imatinib, at baseline and after successful desensitization, were analyzed using flow cytometric analysis. RESULTS By using a slow desensitization technique, all patients were able to receive 400 mg/d of imatinib, and prednisolone was gradually tapered off. The percentages of imatinib-induced CD4+CD25+CD134+ T cells decreased from a mean (SD) of 11.3% (6.5%) and 13.4% (7.3%) at baseline to 3.2% (0.7%) and 3.0% (1.1%) after successful desensitization, when stimulating peripheral blood mononuclear cells with 1 and 2 μM of imatinib, respectively. CONCLUSION Slow desensitization is a helpful procedure in treating patients with imatinib-induced nonimmediate reactions other than simple maculopapular exanthema. The reduced percentages of imatinib-induced CD4+CD25+CD134+ T cells in these patients may be associated with immune tolerance.

DNA Methylation Status of the Interspersed Repetitive Sequences for LINE-1, Alu, HERV-E, and HERV-K in Trabeculectomy Specimens from Glaucoma Eyes

Background/Aims Epigenetic mechanisms via DNA methylation may be related to glaucoma pathogenesis. This study aimed to determine the global DNA methylation level of the trabeculectomy specimens among patients with different types of glaucoma and normal subjects. Methods Trabeculectomy sections from 16 primary open-angle glaucoma (POAG), 12 primary angle-closure glaucoma (PACG), 16 secondary glaucoma patients, and 10 normal controls were assessed for DNA methylation using combined-bisulfite restriction analysis. The percentage of global methylation level of the interspersed repetitive sequences for LINE-1, Alu, HERV-E, and HERV-K were compared between the 4 groups. Results There were no significant differences in the methylation for LINE-1 and HERV-E between patients and normal controls. For the Alu marker, the methylation was significantly lower in all types of glaucoma patients compared to controls (POAG 52.19% versus control 52.83%, p = 0.021; PACG 51.50% versus control, p = 0.005; secondary glaucoma 51.95% versus control, p = 0.014), whereas the methylation level of HERV-K was statistically higher in POAG patients compared to controls (POAG 49.22% versus control 48.09%, p = 0.017). Conclusions The trabeculectomy sections had relative DNA hypomethylation of Alu in all glaucoma subtypes and relative DNA hypermethylation of HERV-K in POAG patients. These methylation changes may lead to the fibrotic phenotype in the trabecular meshwork.