Yunying Shi

Disturbed Th17/Treg balance in patients with rheumatoid arthritis

Proinflammatory Th17 cells and CD4+CD25+ regulatory T (Treg) cells are two newly identified T lymphocyte subsets, which have opposite effects on autoimmunity and inflammation. To assess the Th17/Treg pattern and cytokine microenvironment in peripheral blood of patients with RA, we included 66 RA patients and 20 healthy volunteers. Of all these subjects, peripheral Th17 and Treg frequencies were analyzed by flow cytometry (FCM) and the plasma levels of interleukin (IL)-17, 23, 6, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1 were detected by ELISA. The results demonstrated that RA patients revealed an obvious increase in peripheral Th17 frequencies and levels of Th17-related cytokines (IL-17, IL-23, IL-6, TNF-α) while a significant decrease in Treg frequencies and Treg-related cytokine (TGF-β1) levels when compared with healthy people. Our study indicated that development of RA is associated with peripheral Th17/Treg imbalance and characterized by a proinflammatory cytokine microenvironment, which supports continuing generation of Th17 cells.

Association of polymorphisms in pre-miRNA with inflammatory biomarkers in rheumatoid arthritis in the Chinese Han population

The aim of this study was to detect the association between 2 single nucleotide polymorphisms (SNPs), rs2910164 G>C and rs3746444 T>C, in pre-miRNA (hsa-mir-146a and hsa-mir-499) and the chronic inflammation in the Chinese Han population with rheumatoid arthritis (RA). Two hundred sixty-two Han Chinese patients with RA were recruited in this study. The SNPs were genotyped by polymerase chain reaction restriction fragment length polymorphism. C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and the plasma concentrations of interleukin (IL)-6, tumor necrosis factor α (TNF-α), and transforming growth factor β1 (TGF-β1) were measured. There was a significant difference in the levels of CRP and ESR among different genotypes in rs3746444 (p = 0.031 and p = 0.047, respectively). The heterozygote CT had significantly higher levels of CRP and ESR compared with homozygotes CC and TT. No significant association was observed between the SNP rs2910164 and the levels of CRP, ESR, IL-6, TNF-α, and TGF-β1 (all p > 0.05). The results of this study provided the first evidence that the SNP rs3746444 in pre-miR-499 could affect the inflammatory reaction in patients with RA. The findings were significant and might contribute to the clinical assessment of inflammatory activity, which in turn may influence therapeutic decision making.

Pharmacogenetic aspects of the use of tacrolimus in renal transplantation: recent developments and ethnic considerations

ABSTRACT Introduction: Tacrolimus (Tac) is effective in preventing acute rejection but has considerable toxicity and inter-individual variability in pharmacokinetics and pharmacodynamics. Part of this is explained by polymorphisms in genes encoding Tac-metabolizing enzymes and transporters. A better understanding of Tac pharmacokinetics and pharmacodynamics may help to minimize different outcomes amongst transplant recipients by personalizing immunosuppression. Areas covered: The pharmacogenetic contribution of Tac metabolism will be examined, with a focus on recent discoveries, new developments and ethnic considerations. Expert opinion: The strongest and most consistent association in pharmacogenetics is between the CYP3A5 genotype and Tac dose requirement, with CYP3A5 expressers having a ~ 40–50% higher dose requirement compared to non-expressers. Two recent randomized-controlled clinical trials using CYP3A5 genotype, however, did not show a decrease in acute rejections nor reduced toxicity. CYP3A4*22, CYP3A4*26, and POR*28 are also associated with Tac dose requirements and may be included to provide the expected improvement of Tac therapy. Studies focusing on the intracellular drug concentrations and on calcineurin inhibitor-induced nephrotoxicity also seem promising. For all studies, however, the ethnic prevalence of genotypes should be taken into account, as this may significantly impact the effect of pre-emptive genotyping.

Anti-TNF-α therapy improves Treg and suppresses Teff in patients with rheumatoid arthritis

Anti-TNF-α therapies have been applied in RA treatment, but the regulatory effect of the drug on immune system is not clear. In this study, we included 33 active RA patients and divided them into two groups. One group received anti-TNF-α mAb+methotrexate for 24 weeks, the other group got placebo+methotrexate for the first 12 weeks and anti-TNF-α mAb+methotrexate for another 12 weeks. Circulatory regulatory T cell (Treg) and effector T cell (Teff) frequency was analyzed pre-therapy and week 12 and week 24 for both group patients by flowcytometry. Our results indicated significantly elevated Treg and decreased Teff at week 24 compared with pre-therapy and week 12 for both group patients, and a little higher Treg and lower Teff frequency in anti-TNF-α therapy group than in placebo therapy patients. Our results demonstrated anti-TNF-α therapy has regulatory effect on immune system of RA patients by promoting Treg proportion increase and suppressing Teff.

Myoglobin clearance by continuous venous-venous haemofiltration in rhabdomyolysis with acute kidney injury: a case series.

BACKGROUND Clearance of circulating myoglobin is a critical measure to prevent further damage in patients with rhabdomyolysis (RM) and acute kidney injury (AKI). Continuous venous-venous haemofiltration has emerged to be a novel approach for this purpose. The objective of present study is to evaluate the efficacy and safety of CVVH in myoglobin clearance for patients with RM complicated with AKI. METHOD We prospectively analysed 15 patients with acute RM and AKI due to crush syndrome (n=7), bee stings (n=5), polymyositis (n=2) and heroin poisoning (n=1). All of them presented oliguria with high serum myoglobin and creatine kinase concentration. They were treated by CVVH for at least 48h until the conditions turned to be stable, then replaced by intermittent renal replacement therapy (intermittent haemofiltration or haemodialysis). Meanwhile intravascular volume expansion, urinary alkalinisation, and forced diuresis were administered. During the procedure, serum and effluent concentrations of myoglobin and creatinine were measured simultaneously at 2, 6, 12 and 24h. RESULT The mean sieving coefficients for myoglobin were 0.28±0.06, 0.21±0.06, 0.15±0.02 and 0.11±0.02 during 2, 6, 12 and 24h of CVVH intervention, whilst mean clearance of myoglobin was 14.3±3.1ml/min during 2h and reduced to 11.5±3.2, 7.5±0.9, 5.6±1.0ml/min during 6, 12 and 24h. In contrast to myoglobin, the sieving coefficient for creatinine remained stable at 0.95±0.25, 1.02±0.12, 0.89±0.32, 0.98±0.27 during 24h of CVVH. In all of the 15 patients, serum myoglobin and creatine kinase were dramatically decreased in 24h (-56.2 and -32.1%), 3 days (-72.9 and -50.3%) and in 7 days (-97.6 and -96.7%). Seven patients (46.7%) complicated with hypophosphatemia during CVVH intervention improved in natural course after the cessation of CVVH. After 16±12 days, all of 15 patients came to polyuria stage and finally, discharged with normal renal function after 31±15 days. CONCLUSION Our study showed CVVH can be employed to clear myoglobin effectively in patients with RM and AKI and presented oliguria. This indicate that CVVH would be better than other modes of renal replement treatment in acute RM with AKI because of the additional benefit of myoglobin removal, but large sample randomised controlled trials are still required to confirm it.

The Value of Plasma Paraquat Concentration in Predicting Therapeutic Effects of Haemoperfusion in Patients with Acute Paraquat Poisoning

Objective This study was aimed to analyze the scavenging effect of haemoperfusion on plasma paraquat (PQ) and to evaluate the clinical significance of PQ examination in the treatment of patients with acute paraquat poisoning. Methods 85 patients with acute paraquat intoxication by oral ingestion were admitted in West China Hospital from Jun, 2010 to Mar, 2011. A standardized therapeutic regimen including emergency haemoperfusion was given on all subjects. A total of 91 whole blood samples were taken before (0h), underway (1h after haemoperfusion beginning) and at the end (2h) of the haemoperfusion therapy. The clearance rate was calculated and related factors were analyzed. Results As heamoperfusion was going on, the plasma paraquat concentration of the patients kept falling down. After 1 hour of haemoperfusion, the average clearance rate (R1) was 37.06±21.81%. After 2 hours of haemoperfusion, the average clearance rate (R2) was 45.99±23.13%. The average of R1/R2 ratio was 76.61±22.80%. In the high paraquat concentration group (plasma paraquat concentration (C0) >300 ng/mL), both the averages of R1 and R2 were significantly higher than those of the low paraquat concentration group (C0≤200 ng/mL) (p<0.05), and there was no significant difference of R1/R2 between these two groups (p>0.05). Conclusions The dynamic monitoring of plasma PQ concentration was not only critical in the clinical evaluation but also helpful in guiding the treatment of patients with acute PQ intoxication. Haemoperfusion can effectively eliminate paraquat from the plasma in patients with high initial plasma PQ concentration, while in patients with low initial plasma PQ concentration (<200 ng/ml), the clearance effect of harmoperfusion was very limited. Increasing HP time might improve the overall clearance rate of HP on plasma PQ yet decrease the elimination efficiency of HP, while repeated HP treatment was helpful against the rebound phenomena.

CNI induced Th17/Treg imbalance and susceptibility to renal dysfunction in renal transplantation.

Calcineurin inhibitors (CNI) prevent graft rejection by blocking interleukin-2 (IL-2), which was required for development and function of Foxp3(+)CD4(+)CD25(+) regulatory T cells (Treg). Recently, IL-2 was reported to play a part in the inhibition of Th17 cells. The renal transplantation recipient who used CNI regularly might have Th17/Treg imbalance with increased Th17 cells and decreased Treg cells, which would cause renal dysfunction even rejection. To assess the effect of CNI on Th17 cells and Treg cells, we included 123 renal transplantation recipients (101 in a stable stage and 22 with renal dysfunction) and 27 healthy volunteers. Among all the recipients, 103 recipients used CNI and 20 recipients used sirolimus without CNI. The recipients who used CNI were further classified into four groups according to the blood levels of CNI: Of all these subjects, Th17 and Treg frequencies in the peripheral blood were analyzed by flow cytometry (FCM). Serums IL-17, IL-23, IL-6, IFN-r, and TGF-β were analyzed by ELISA. The results demonstrated that the transplantation recipient treated by CNI revealed an obvious increase in peripheral Th17 frequencies and a significant decrease in Treg frequencies when compared with the sirolimus group and healthy people (P<0.05). Even more, the transplantation recipient with renal dysfunction had the highest level of Th17 cells (P<0.05) while the lowest Treg cells compared with stable recipient and healthy control, with increased serums IL-6 and IL-17. Our results indicated that CNI was associated with Th17/Treg imbalance in peripheral blood, which supported the followed generation of renal dysfunction after transplantation.

Specific serum protein biomarkers of rheumatoid arthritis detected by MALDI-TOF-MS combined with magnetic beads.

OBJECTIVES To identify novel serum protein biomarkers and establish diagnostic pattern for rheumatoid arthritis (RA) by using proteomic technology. METHODS Serum proteomic spectra were generated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) combined with weak cationic exchange magnetic beads. A training set of spectra, derived from analyzing sera from 22 patients with RA, 26 patients with other autoimmune diseases and 25 age- and sex-matched healthy volunteers, was used to train and develop a decision tree model with a machine learning algorithm called decision boosting. A blinded testing set, including 21 patients with RA, 24 patients with other autoimmune diseases and 25 healthy people, was used to examine the accuracy of the model. RESULTS A decision tree model was established, consisting of four potential protein biomarkers whose m/z values were 4966.88, 5065.3, 5636.97 and 7766.87, respectively. In validation test, the decision tree model could differentiate RA from other autoimmune diseases and healthy people with the sensitivity of 85.71% and specificity of 87.76%, respectively. CONCLUSIONS The present data suggested that MALDI-TOF-MS combined with magnetic beads could screen and identify some novel serum protein biomarkers related to RA. The proteomic pattern based on the four candidate biomarkers is of value for laboratory diagnosis of RA.

Impact of tacrolimus on bone metabolism after kidney transplantation.

Bone disease is a common clinical problem after kidney transplantation. To date, studies investigating the effects of tacrolimus (TAC) on bone metabolism in vivo or vitro yielded conflicting data. This study was carried out to discuss the relationship between TAC blood concentrations and bone metabolism status in kidney transplant recipients. 72 kidney recipients whose time since transplantation more than 5 months (5-51 months) were divided into two groups by the TAC blood concentrations, high TAC group (TAC≥6 ng/mL) and low TAC group(TAC<6 ng/mL), respectively. Bone mineral density (BMD) of lumbar vertebrae L1-L4 and neck of the femur and allied biochemical markers (TRAP-5b, B-ALP, 25-(OH)D, PTH, beta-CrossLaps, N-MID Osteocalcin, Ca, PO4) were measured simultaneously. Our results showed that 27.78% of our patients had bone loss and the loss rates were statistical different between the high TAC group and low TAC group in kidney recipients (45.5% vs 20.0%, P=0.026). Correlation analysis showed that TAC concentrations were positively correlated with tartrate-resistant acid phosphatase-5b (TRAP-5b) in male recipients (r=0.287, P<0.05). In conclusion, kidney transplant recipients with high TAC blood concentrations are at risk of bone loss, and TAC may cause bone disorders involved in accelerated bone resorption.

Association of polymorphisms in interleukin‐18 and interleukin‐28B with Hepatitis B recurrence after liver transplantation in Chinese Han population

Interleukin‐18 (IL‐18) is a potent proinflammatory cytokine, which can promote hepatitis B virus clearance. The latest studies find that genetic polymorphisms near the IL‐28B gene are strongly associated with sustained viral response and spontaneous viral clearance in patients with chronically infected hepatitis C and hepatitis B. We investigated the effect of rs187238 and rs1946518 in IL‐18 gene and rs8099917 in IL‐28B gene on HBV recurrence in liver transplant patients. A total of 200 liver transplant recipients and relevant donors were enrolled in this study. The patients’ mean follow‐up was 39 month (range 10–65 month). All liver transplant recipients were in a stable stage. The total recipients (n = 200) were divided into end‐stage liver disease secondary to hepatitis B (n = 140) and end‐stage liver disease secondary to other diseases (n = 60) before transplantation. Recipients (n = 140) with hepatitis B before transplantation were defined to nonHBV recurrence group (n = 119) or HBV recurrence group (n = 21), which was positive for HBsAg or elevatory in HBV DNA (>2.0 × 102 IU mL−1) after transplantation. For the recipients (n = 140) had hepatitis B before transplantation, we studied the single‐nucleotide polymorphisms (SNPs) of IL‐18 gene (rs187238 and rs1946518) and IL‐28B gene (rs8099917) by high‐resolution melting (HRM) curve analysis. The serum levels of IL‐18 and IFN‐γ were tested by ELISA. The serums levels of IFN‐γ were lower in HBV recurrence group than that in nonHBV recurrence group (P < 0.01). The genotype of IL‐28B gene rs8099917 was associated with alanine aminotransferase (ALT) levels and aspartate aminotransferase (AST) levels in HBV‐related liver transplant recipients (n = 140). The recipients with allele G (GG+GT) had higher ALT and AST levels (P < 0.05). No association was found between IL‐18 gene and IL‐28B gene polymorphisms with HBV recurrence in the liver transplant recipients or the donors. We identified that the IFN‐γ was a protective factor of HBV recurrence after liver transplantation. The allele G of rs8099917 was associated with hepatitis B‐related hepatocytes injury. The rs8099917 G allele subgroup should reinforce antiviral therapy.