H.S. Ciftci

Genetic association of interleukin-2, interleukin-4, interleukin-6, transforming growth factor-β, tumour necrosis factor-α and blood concentrations of calcineurin inhibitors in Turkish renal transplant patients.

Cytokines are essential for the control of the immune response as most of the immunosuppressive drugs target cytokine production or their action. The calcineurin inhibitors (CNIs) cyclosporine (CsA) and tacrolimus are immunosuppressive drugs widely used after renal transplantation to prevent allograft rejection. They are characterized by large interindividual variability in their pharmacokinetics; therefore, monitoring their blood concentrations is important to predict their optimal dosage following transplantation. Calcineurin inhibitors inhibit the phosphatase activity of calcineurin, thereby suppressing the production of other cytokines such as transforming growth factor (TGF‐β), tumour necrosis factor‐α (TNF‐α), interleukin (IL)‐6, IL‐2, and IL‐4. The aim of this study was to investigate the relationship between polymorphisms of cytokines and blood concentrations of CNIs in renal transplant patients. The study included 53 CsA‐treated renal transplant patients and 37 tacrolimus‐treated renal transplant patients. Cytokine polymorphisms were analysed using polymerase chain reaction (PCR) sequence‐specific primers with the cytokine CTS‐PCR‐sequence‐specific primers Tray Kit; University of Heidelberg. Blood concentrations of CNIs were determined with Cloned Enzyme Donor Immunoassay (CEDIA) method. Patients with TC genotype of TGF‐β at codon 10 had lower CsA blood concentrations than the TT and CC genotypes (P = 0.005) at 1 month in CsA treatment group. The ratio of blood concentration/dose of CsA for patients with TGF‐β1‐codon 10 TC genotype was lower than for patients with TT, CC genotypes, and the dose given to these patients was higher in the first month (P = 0.046). The ratio of blood concentration/dose of CsA for patients with IL‐2‐330 GG genotype was higher than for patients with GT, TT genotypes, and the dose given to these patients was lower at first month and sixth months (P = 0.043, P = 0.035 respectively). The tacrolimus blood concentrations were significantly higher in patients with the genotype GG of IL‐2‐330 (P = 0.012) at the third month. Patients who had the TC genotype TGF‐β codon 10 had lower CsA blood concentrations and this group had higher acute rejection (P = 0.033). These results suggest that the genotyping for TGF‐β‐codon 10, IL‐2‐330 and IL‐6‐174 polymorphisms may help individualized immunosuppressive dosage regiments.

Effect of MDR1 Polymorphisms on the Blood Concentrations of Tacrolimus in Turkish Renal Transplant Patients

BACKGROUND Tacrolimus, a calcineurin inhibitör, is prescribed to prevent allograft rejection in renal transplantation. Tacrolimus not only has a narrow therapeutic index, but also shows significant interindividual differences. The absorption and metabolism of this drug are affected by multidrug resistance (MDR) 1 gene polymorphisms that correlated with single-nucleotide polymorphisms (SNPs) affecting in vivo P-glycoprotein activity. This study investigated associations of MDR1 gene C3435T polymorphism with tacrolimus blood concentrations and dose requirements as well as acute rejection episodes among Turkish renal transplant patients. METHODS One hundred living-donor transplant recipients and 150 healthy control subjects underwent C3435T genotyping using polymerase chain reaction-restriction fragment length polymorphism. Blood concentrations of tacrolimus were determined with the cloned enzyme donor immunoassay. RESULTS The CC, CT, and TT genotype frequencies among patients were, respectively, 44.0%, 33.0%, and 23.0% versus 36.7%, 43.3%, and 20.0% among control subjects. There was no significant difference between (P = .061; P = .102; P = .211; respectively). The ratio of blood concentration to dose of tacrolimus for patients with mutant homozygous 3435 TT genotype was higher than that of wild-type 3435 CC genotype homozygous individuals. The doses for these patients were lower at 1, 3, and 12 months (P = .048; P = .03; P = .041, respectively). There were no significant differences between the groups regarding coprescription of drugs that affect tacrolimus concentrations, such as diltiazem. Acute rejection episodes were not associated with the CC vs CT or TT genotypes: odds ratio (OR), 0.517 (95% confidence interval [CI], 0.190-1.407; P = .192); OR 1.558 (95% CI, 0.587-4.136; P = .372); OR 1.346; (95% CI, 0.456-3.968; P = .590), respectively. CONCLUSIONS Determination of MDR1 polymorphism may help to achieve target of tacrolimus blood concentrations.

Flow Cytometric Evaluation of Pregnancy-Induced Anti-Donor Immunization

BACKGROUND Living donor kidneys from spouses and children (from offspring to parents) are currently considered to be important organ sources. However, pregnancy-induced alloimmunization may provoke acute rejection episodes after kidney transplantation. being flow cytometry cross-match (FCXM) we studied donor-specific antibodies (DSAs) in the sera of recipients planned for living kidney transplantation from their spouse or children. When the FCXM was positive, we confirmed the existence of anti-human leukocyte antigen (HLA) antibodies using flow cytometry panel-reactive antibody (flow-PRA). PATIENTS AND METHODS Between March 2005 and November 2010, we tested 85 pretransplantation sera from renal transplant recipients for DSAs. The recipients included 37 wives (group I) and 48 husbands (group II). FCXM-positive sera were tested using a flow-PRA screening method using HLA class I and class II antigen-coated beads. The mean recipient age was 48.1 ± 9.8 (range, 28-69) years and the mean donor age was 45.1 ± 11.1 (range, 23-69 years). RESULTS Among group I were 18 (48.6%) FCXM-positive cross-matches; for group II, 5 (10.4%) cases (P = .001). Sensitized patients were 37.9% FCXM-positive, whereas nonsensitized patients were 3.7% positive (P = .001). FCXM-positive patients were re-evaluated for anti-HLA antibodies using flow-PRA. Seventeen of 18 group I tests (94.4%) were FCXM-positive, whereas 3 of 5 (60%) were positive among group II. CONCLUSIONS We concluded that flow cytometry-based cross-match and PRA techniques can be used to detect anti-HLA antibodies using spousal or children donors for kidney transplantation.

Comparing the Effects of Combined General/Epidural Anaesthesia and General Anaesthesia on Serum Cytokine Levels in Radical Cystectomy

OBJECTIVE Surgical stress combined with general anaesthesia (GA) suppresses the immune system and leads to cancer cell growth and premature metastasis in major oncological interventions. Epidural analgesia decreases the need for inhalation agents and opioids during surgery by suppressing sympathetic and neuroendocrine responses in the postoperative period. This study aimed to compare the effects of combined general/epidural anaesthesia (GEA)+patient-controlled epidural analgesia (PCEA) and GA+IV patient-controlled analgesia (PCA) on serum tumour necrosis factor-alpha TNF-α), interleukin-1 beta (IL-1β) and interferon-gamma (IFN-γ) levels in patients undergoing radical cystectomy. METHODS Sixty-five patients were enrolled in this prospective study. Patients were randomly enrolled to the GEA group, i.e., combined GEA+ PCEA (0.1% bupivacaine+1 μg mL-1 fentanyl), and the GA group, namely combined GA+IV PCA (0.03 mg mL-1 morphine). To evaluate the cytokine response, blood samples were collected at preoperative, postoperative 1st and 24th hours. RESULTS There was no statistically significant difference in serum TNF-α, IL-1β and IFN-γ levels between groups GA and GEA at preoperative and postoperative 1st hour and 24th hour. Total remifentanil consumption was significantly lower and length of hospital stay was significantly shorter in the GEA group than in the GA group (p<0.05). CONCLUSION There is no difference between two anaesthesia methods in terms of serum cytokine levels; however, combined GEA+PCEA technique appeared to be superior to GA+IV PCA because of lower intraoperative narcotic analgesic consumption and shorter hospital stay.

Serum and Urinary Levels of Tumor Necrosis Factor-Alpha in Renal Transplant Patients

OBJECTIVES Allograft rejection is an important cause of early and long-term graft loss in kidney transplant recipients. Tumor necrosis factor-alpha promotes T-cell activation, the key reaction leading to allograft rejection. Here, we investigated whether serum and urinary tumor necrosis factor-alpha levels can predict allograft rejection. MATERIALS AND METHODS This study included 65 living related-donor renal transplant recipients with mean follow-up of 26 ± 9 months. Serum and urinary tumor necrosis factor-alpha levels were measured at pretransplant and at posttransplant time points (days 1 and 7 and months 3 and 6); serum creatinine levels were also monitored during posttransplant follow-up. Standard enzyme-linked immunoabsorbent assay was used to detect tumor necrosis factor-alpha levels. Clinical variables were monitored. RESULTS Nine of 65 patients (13.8%) had biopsy-proven rejection during follow-up. Preoperative serum and urinary tumor necrosis factor-alpha levels were not significantly different when we compared patients with and without rejection. Serum tumor necrosis factor-alpha levels (in pg/mL) were significantly higher in the allograft rejection versus nonrejection group at day 7 (11.5 ± 4.7 vs 15.4 ± 5.8; P = .029) and month 1 (11.1 ± 4.8 vs 17.8 ± 10.9; P =.003). Urinary tumor necrosis factor-alpha levels (in pg/mL) were also elevated in the allograft rejection versus the nonrejection group at days 1 (10.2 ± 2.5 vs 14.1 ± 6.8; P = .002) and 7 (9.8 ± 2.2 vs 14.5 ± 2.7; P < .001) and at months 1 (8.0 ± 1.7 vs 11.8 ± 2.4; P < .001), 3 (7.7 ± 1.6 vs 9.6 ± 1.7; P = .002), and 6 (7.4 ± 1.6 vs 8.9 ± 0.9; P = .005). CONCLUSIONS Our preliminary findings suggest that tumor necrosis factor-alpha has a role in diagnosing renal transplant rejection. Serum and urinary tumor necrosis factor-alpha levels may be a possible predictor for allograft rejection.

The predictive value of stimulation index calculated by modified mixed lymphocyte culture in the detection of GVHD following hematopoietic stem cell transplantation

OBJECTIVE Mixed lymphocyte culture (MLC) is one of the routine tests performed prior to hematopoietic stem cell transplantation (HSCT) as a predictive assay for assessing the quality of donor matching and graft-versus-host disease (GVHD). The stimulation index is one of the formulas of the MLC test, and it is used for evaluation of matching between donor and recipient. Modified MLC (mMLC) test is produced by adding various cytokines to the MLC test, and increased sensitivity has been reported with this modification. METHODS The importance of the stimulation index values in MLC and mMLC tests was evaluated in 59 patients who received HSCs from human leukocyte antigen-identical sibling donors. In the mMLC test, cytokines were added as interleukin (IL)-2, IL-2 + IL-4 and IL-2 + interferon (IFN)-gamma + tumor necrosis factor (TNF)-alpha. Stimulation index values in mMLC test were compared with stimulation index values in MLC test. RESULTS Twenty-three (39%) patients developed GVHD. When evaluated in terms of stimulation index >1 patients, in MLC, 55% of the patients developed GVHD (p=0.229), whereas these values were 75% in the IL-2 added mMLC test (p=0.035), 100% in the IL-2 + IL-4 added mMLC test (p=0.076) and 85.7% in the IL-2 + IFN-gamma + TNF-alpha added mMLC test (p=0.015). CONCLUSION mMLC increased the sensitivity of the test. The relation between the positive results and evidence of GVHD after transplantation was found significant.