The Polymorphism rs3024505 (C/T) Downstream of the IL10 Gene Is Associated with Crohn's Disease in Serbian Patients with Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD), manifesting as Crohn's disease (CD) and ulcerative colitis (UC), is characterized by recurring episodes of inflammation in gastrointestinal tract, in which aberrant production of regulatory cytokine interleukin-10 (IL-10) presumably plays important role. Single nucleotide polymorphisms (SNPs) that affect IL-10 production, such as rs1800896 (G/A) at position -1082 and rs1800871 (C/T) at position -819 in the promoter region of the IL10 gene, have been associated with CD and/or UC, but the results were inconsistent. Another SNP that may alter IL-10 production, rs3024505 (C/T) located immediately downstream of the IL10 gene has been recently identified. T allele of rs3024505 was associated with both UC and CD in Western populations, but the studies from East European countries are lacking. Therefore, our aim was to assess the association of rs3024505, rs1800896 and rs1800871 with Serbian IBD patients. To this end, 107 CD and 99 UC patients and 255 healthy controls were genotyped. As a result, T allele of rs3024505 was associated with CD at allelic, genotypic (GT genotype) and haplotypic (GCCT haplotype) level, suggesting potential role of this variant in susceptibility to CD. In contrast, CD patients carrying C allele of rs3024505 had significantly increased risk of anemia and stricturing/penetrating behavior. No association was observed between rs3024505 and UC or SNPs in IL10 promoter region and any form of IBD. In conclusion, rs3024505 SNP flanking the IL10 gene is associated with susceptibility and severity of disease in Serbian CD patients, further validating its role as a potential biomarker in IBD.

Immune Evasion of SARS-CoV-2 Emerging Variants: What Have We Learnt So Far?

Despite the slow evolutionary rate of SARS-CoV-2 relative to other RNA viruses, its massive and rapid transmission during the COVID-19 pandemic has enabled it to acquire significant genetic diversity since it first entered the human population. This led to the emergence of numerous variants, some of them recently being labeled "variants of concern" (VOC), due to their potential impact on transmission, morbidity/mortality, and the evasion of neutralization by antibodies elicited by infection, vaccination, or therapeutic application. The potential to evade neutralization is the result of diversity of the target epitopes generated by the accumulation of mutations in the spike protein. While three globally recognized VOCs (Alpha or B.1.1.7, Beta or B.1.351, and Gamma or P.1) remain sensitive to neutralization albeit at reduced levels by the sera of convalescent individuals and recipients of several anti-COVID19 vaccines, the effect of spike variability is much more evident on the neutralization capacity of monoclonal antibodies. The newly recognized VOC Delta or lineage B.1.617.2, as well as locally accepted VOCs (Epsilon or B.1.427/29-US and B1.1.7 with the E484K-UK) are indicating the necessity of close monitoring of new variants on a global level. The VOCs characteristics, their mutational patterns, and the role mutations play in immune evasion are summarized in this review.

VEGF gene polymorphism association with diabetic neuropathy.

Vascular factors beside metabolic problems are involved in both etiopathogenesis of diabetic neuropathy, and more remarkably, later in "repair" phase, that governs the net balance between neuro-regenerative/degenerative reactions. Regarding ischemic nature of diabetic neuropathy that highlights necessity of blood vessels re-establishment during tissue healing, VEGF (vascular endothelial growth factor) has been recently the subject of extensive investigations in diabetic neuropathy (DNU). This growth factor possesses angiogenic potentials in addition to the hemodynamic functions. The distribution of VEGF gene polymorphisms at positions -7*C/T, -1001*G/C, -1154*G/A and -2578*C/A were analysed by ARMS-PCR in 248 type 1 diabetic British-Caucasian subjects (81 DNU+, 167 DNU-). We have found that distribution of a VEGF gene polymorphism at promoter region (-7*C/T) was significantly different between diabetic subjects with vs. without neuropathy and the allele (C) conferred susceptibility to DNU (P = 0.02; OR = 1.78, 95% CI 1.0-3.1). The present study indicates that polymorphism of the VEGF gene at position -7*C/T might be implicated in the pathogenesis of diabetic neuropathy as it may harbour some functional/regulatory potential in VEGF gene expression. However, this requires further studies in order to better understand its phenotypic impact and to investigate the prognostic value of this polymorphism in diabetic neuropathy as a chronic complication of diabetes.

Inosine 5'-monophosphate dehydrogenase 1 haplotypes and association with mycophenolate mofetil gastrointestinal intolerance in pediatric heart transplant patients.

MMF, the most commonly used adjuvant immunosuppressant in pediatric heart transplantation, has frequent GI adverse events. SNPs in inosine 5'-monophosphate dehydrogenase I (IMPDH1) may contribute to MMF GI intolerance. Phased haplotypes may have more utility than individual SNPs in candidate gene association studies for complex traits. This study defined common IMPDH1 haplotypes and investigated whether these haplotypes influence MMF GI intolerance in 59 pediatric heart recipients. Genotypes were assessed by Taqman analysis of IMPDH1 rs2288553, rs2288549, rs2278293, rs2278294, and rs2228075, and haplotypes were inferred using Arlequin 3.01 software. GI intolerance was defined as diarrhea, vomiting, nausea, or abdominal pain requiring MMF dose holding for > 48 h or MMF discontinuation. GI intolerance occurred in 21 patients (35.6%). Ten IMPDH1 haplotypes were identified in this population. In univariable analyses, one haplotype was strongly associated with MMF GI intolerance with 59.1% of carriers of this haplotype experiencing MMF GI intolerance compared to 21.6% of non-carriers (p = 0.005). In this study, we identify a common IMPDH1 haplotype associated with MMF GI intolerance in a population of pediatric heart transplant patients. This haplotype of interest did not demonstrate stronger association with MMF GI intolerance than an individual IMPDH1 SNP.

A novel method for monitoring glucocorticoid-induced changes of the glucocorticoid receptor in kidney transplant recipients.

INTRODUCTION: Initial high dose glucocorticosteroid (GC) treatment of transplant recipients induces changes in the glucocorticoid receptor (GR) that may affect the mode of action of the drug. We developed a TaqMan one-step RT-PCR quantification method to investigate the effect of bolus GC treatment on the structure of the GR complex by measuring the levels of GR isoform expression and FK binding protein 5 (FKBP5) transcription. METHODS: Peripheral blood mononuclear cells (PBMCs) were obtained before renal transplantation and immediately after the initial methylprednisolone treatment. Gene expression of the GR-alpha, -beta, -P isoforms and FKBP5 were quantified using a simplex TaqMan relative quantification assay. Genotyping was performed using the TaqMan allele discrimination assay. RESULTS: The gene expression assay was validated and is efficient to detect extremely low quantity of GR-beta expression. Increased expression of FKBP5 (14.01+11.52 folds), GR-alpha (1.47+1.00 folds), GR-beta (6.21+5.71 folds) and GR-P (2.72+1.90 folds) were observed after steroid bolus. The GR haplotype A-T-G is significantly related to elevation of GRbeta transcription (p=0.002). Patients' hospitalization time after transplantation correlated with increment of GR-alpha (p=0.01) and FKBP5 (p=0.007) gene expression. The GR-beta expression level is extremely low compared with the GR-alpha isoform. By contrast, the GR-P isoform is relatively abundantly expressed in PBMCs. CONCLUSION: The method to measure GR isoform enabled us to determine that acute high-dose GC treatment alters the structure of the GR. The initial therapy with high dose steroid may induce a GC resistance phenotype. The modulatory role of the GR-P isoform is not fully defined but may provide another dimension in understanding the function of GR and the role of steroid in transplant immunosuppression.

Genetic polymorphisms of MRP2 and UGT2B7 and gastrointestinal symptoms in renal transplant recipients taking mycophenolic acid.

The aim of this study was to determine the relationship between single nucleotide polymorphisms in multidrug resistance protein 2 (MRP2) and uridine diphosphate glucuronosyltransferase (UGT) 2B7 and the severity of gastrointestinal (GI) symptoms in patients receiving mycophenolic acid (MPA). A total of 67 renal transplant recipients taking MPA derivatives were included in the study. Genotypes for MRP2 C-24 T and UGT2B7 C802 T were determined. The incidence and severity of GI symptoms were assessed using the validated Gastrointestinal Symptom Rating Scale (GSRS) at baseline, 2 weeks, 3 months, and 6 months after transplantation. The mean overall GSRS score and the score on the subscale for diarrhea were compared using the Kruskal-Wallis test. The overall GSRS scores (23.5 +/- 4.5 vs. 26.7 +/- 9.9, P = 0.68) or diarrhea subscores (3.5 +/- 0.9 vs. 5.1 +/- 3.3, P = 0.08) were not significantly different among patients with the heterozygous variant MRP2 C-24 T and those with the homozygous wild type. For UGT2B7, the overall mean GSRS scores were significantly different between the homozygous wild type and the variant type (CC vs. CT + TT, 29.2 +/- 9.3 vs. 24.0 +/- 8.2, P = 0.009), although diarrhea subscale scores did not reach statistical significance (CC vs. CT + TT, 5.7 +/- 4.1 vs. 4.1 +/- 1.9, P = 0.13). When the genotypes for MRP2 and UGT2B7 were considered together, patients with the variant forms of MRP2 and UGT2B7 had significantly lower overall GSRS scores (CC-CC vs. CT-CT/TT, 22.5 +/- 4.3 vs. 30.1 +/- 10.1, P = 0.04) and diarrhea subscale scores compared to wild type (CC-CC vs. CT-CT/TT, 3.4 +/- 0.7 vs. 6.2 +/- 4.4, P = 0.03). However, there were no differences in GSRS scores between patients receiving either mycophenolic mofetil (MMF) or enteric-coated mycophenolic acid (EC-MPA) regardless of whether the patients were receiving different calcineurin inhibitors. In conclusion, this study suggests that among patients receiving MPA, those with UGT2B7 variant genotypes are protected from the GI side effects of MPA regardless of the formulation used or concurrent calcineurin inhibitors administered. MRP2 genotypes did not show significant differences in GI side effects among patients taking MPA therapy.

The evolving notion of "senior" kidney transplant recipients.

The maximum age of recipients expected to benefit with a kidney transplant has increased in the past three decades. In 1980, patients older than age 50 were not listed for a transplant. In 2004, almost 90% aged 50-60 yr with end-stage renal disease were listed, and some were even older than age 80. We summarize previous articles to illustrate how the notion of "senior" has evolved for kidney transplantation, and using data reported to the Organ Procurement Transplant Network, describe characteristics, treatments and outcomes in recipients older than 50 yr. Fractions of male, white, non-obese, unsensitized recipients and use of expanded criteria donors increased in cohorts with increasing recipient age. The percentage of recipients with hypertension or diabetes decreased, but the percentage with cancer increased. The fraction spared steroids increased with increasing age, but other aspects of immunosuppression were not remarkably different. No differences in early outcomes were notable, and elderly recipients likely did not return to dialysis. However, both graft and patient survival rates decreased with increasing age. Although a small fraction was selected, and survival rates were lower, patients older than 80 yr received kidney transplants.

Cytokine Gene Polymorphism Profiles in Kidney Transplant Patients - Association of +1188A/C RS3212227 SNP in the IL12B Gene Prevents Delayed Graft Function.

BACKGROUND AND AIMS: Transplantation is the best treatment option for end stage kidney disease. The most common early complications in post-transplant period are acute rejection (AR) of the graft and delayed graft function (DGF). The underlying mechanisms in these events are heterogeneous and at least in part involve cytokine genes which regulate immune response to allograft. We have investigated whether functional single nucleotide polymorphisms (SNP) in the genes encoding IFN-γ (IFNG), TNF (TNFA), IL-10 (IL10) and p40 subunit of IL-12/IL-23 (IL12B) could predict risk of AR and DGF in kidney allograft recipients. METHODS: Our study involved 152 kidney transplant recipients on standard immunosuppressive regimen which included calcineurin inhibitors, mycophenolic acid derivatives and corticosteroids. Genotyping of IFNG, TNFA, IL10 and IL12B was performed using commercial TaqMan assays. RESULTS: We found association between the carriers of AA genotype of IL12B +1188A/C polymorphism (rs3212227) and a lower rate of DGF (p = 0.037, OR = 0.45, 95% CI = 0.21-0.96), implying protective role of A allele in the pathogenesis of DGF in kidney transplant recipients, whereas no such association was observed with AR. None of the analyzed SNPs in TNFA (-308G/A), IFNG (+874T/A), IL10 (-1082G/A, -819T/C, -592C/A) were associated with AR or DGF in our patients. CONCLUSIONS: Our study shows a preliminary evidence that the AA genotype of rs3212227 SNP in the IL12B gene might be associated with a lower risk for DGF after kidney transplantation. In the future, additional well-designed large studies are required for the validation of our results.

MDR1 gene polymorphisms are associated with ulcerative colitis in a cohort of Serbian patients with inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic disease of unknown etiology in which genetic factors contribute to development of disease. Single nucleotide polymorphisms (SNPs) in multidrug resistance 1 (MDR1) gene encoding transporter P-glycoprotein have been associated with IBD, but their role in disease susceptibility remains unclear. Therefore, the aim of this study was to investigate the association of three MDR1 polymorphisms, C1236T (rs1128503), G2677T/A (rs2032582) and C3435T (rs1045642), with Serbian IBD patients. METHODS: A total of 206 IBD patients, 107 Crohn's disease (CD) and 99 ulcerative colitis (UC), and 255 healthy controls were included in the study. All subjects were genotyped using TaqMan SNP genotyping assays. Comparisons between the groups were performed using the Pearson Chi-square test. False discovery rate according to Benjamini-Hochberg procedure was applied to adjust for multiple comparisons. RESULTS: Carriers of T allele of all three MDR1 SNPs were more common in UC patients compared to healthy controls, suggesting predisposing role of T allele of these SNPs in UC pathogenesis. Consistently, TT genotype of C1236T and TTT haplotype were also found more frequently in UC patients. On the other hand, C allele and CC genotype of C1236T and C3435T, as well as G allele and GG genotype of G2677T/A were more frequent in healthy subjects, implying protective role of these variants in UC. Likewise, CGC haplotype and CGC/CGC diplotype were more frequent in controls. Contrary to UC, no statistical difference was observed between CD patients and controls in any of the SNPs analyzed. CONCLUSION: MDR1 gene variants and haplotypes were associated with UC in Serbian IBD patients, further supporting their potential role in susceptibility to UC.

Autophagy-independent increase of ATG5 expression in T cells of multiple sclerosis patients.

Autophagy, a process of controlled self-digestion which regulates cell homeostasis, is involved in innate and adaptive immunity. We investigated the expression of autophagy genes and autophagic activity in distinct lymphocyte populations in treatment-naive MS patients. The mRNA and protein levels of autophagy-related (ATG)5, required for autophagosome formation, were increased in CD4+ and CD4- T cells, but not B cells of MS patients compared to control subjects. The expression of other investigated autophagy genes, as well as the autophagic activity, did not significantly differ between the two groups. ATG5 mRNA levels in CD4+ T cells from MS patients were positively correlated with those of the proinflammatory cytokine tumor necrosis factor. These data suggest that autophagy-independent increase in ATG5 expression might be associated with the proinflammatory capacity of T cells in multiple sclerosis.

The MDR1/ABCB1 gene, a high-impact risk factor for cardiac transplant rejection.

BACKGROUND: Variations in the expression and activity levels of the multidrug-resistance MDR1/ABCB1 encoded P- glycoprotein (P-gp) have an impact on the therapeutic efficacy of many drugs. C3435T and G2677 polymorphisms of the MDR1/ABCB1 gene correlate with cellular expression levels of P-gp, a membrane-bound efflux pump which removes a multitude of drugs, including chemotherapy drugs and immunosuppressants, from cells. We aimed to investigate whether the phenomenon of drug resistance, mediated by the MDR1/ABCB1 gene and seen in tumor cells to chemotherapeutic agents, is important in the field of transplantation, predisposing some patients to resistance to immunosuppressants. METHODS: G2677 and C3435T polymorphisms of the ABCB1 gene were determined by PCR in 170 heart transplant recipients. We examined the relationship between MDR1/ABCB1 polymorphisms and endomyocardial biopsy-proven rejection (EBPR) determined by biopsy performed at set intervals according to a standard protocol. RESULTS: A significant relationship was found between a patient's C3435T genotype and freedom from first grade > or =3A rejection episode. 3435-CC recipients were 1.8 times (1.05-3.09; P = 0.03) more likely to undergo a > or =3A rejection episode in the first 12 months. Haplotypes derived from the G2677 and C3435T polymorphisms (GG/CC, GT/CT and TT/TT) amplified this phenomenon further (log rank, P = 0.03; HR 2.18; 1.21-4.26; P = 0.02). CONCLUSIONS: ABCB1 polymorphisms correlate with freedom from grade > or =3A EBPR and we believe that this may be attributed to MDR1/ABCB1 encoded P-gp mediating the efflux of immunosuppressants out of leukocytes, with depleted immunosuppressant levels in leukocytes manifesting as increased cellular rejection.

Platelet-derived growth factor gene polymorphism in recurrent hepatitis C infection after liver transplantation.

BACKGROUND: Recurrent hepatitis C virus (HCV) infection is particularly aggressive in the post liver transplantation setting, with rapid progression of liver fibrosis. Platelet-derived growth factor (PDGF) is reportedly involved in the pathogenesis of liver fibrosis. The aim of this study was to evaluate the possible contribution of molecular variants of the PDGF-B gene to recurrent HCV infection after liver transplantation. METHODS: DNA was extracted from peripheral blood mononuclear cells of 40 patients who underwent liver transplantation for chronic HCV infection and genotyped for polymorphisms in PDGF-B at positions +1135 (A to C) and +286 (A to G). Intrahepatic PDGF-B expression was detected by immunohistochemistry and assessed semiquantitatively. Forty-seven healthy individuals served as controls. RESULTS: Recurrent HCV infection occurred in 34 patients (85%) after a median interval of 10.5 months (range 1.5-60.0). A statistically significant difference was observed in the distribution of the PDGF-B gene polymorphism at position +1135, but not +286 between patients and controls (P=0.05). The A/A genotype occurred at a highly significantly increased rate in patients with recurrent HCV infection than in those without (64.7% vs. 16.67%, P=0.0001), and in patients with severe than in those with nonsevere recurrence (100% vs. 53.85%, P=0.05). The expression level of intrahepatic PDGF-B was found to be highly correlated with the fibrosis stage (P<0.0001). Further analysis yielded a highly statistically significant relationship between the PDGF-B gene polymorphism at position +1135 and clinical parameters of disease severity. CONCLUSIONS: PDGF-B gene polymorphism appears to be associated with severe recurrent HCV infection after liver transplantation. PDGF-B may play an essential role in the development and progression of hepatic fibrosis. These findings, if confirmed, may have important therapeutic implications.

Association of sudden infant death syndrome with VEGF and IL-6 gene polymorphisms.

In the UK, Sudden Infant Death Syndrome (SIDS) is a major cause of postperinatal mortality up to the end of the first year of life. Several studies have found an association between cytokine IL-10 genotypes and SIDS. The aim of the present work was to test the hypothesis that SIDS is associated with high producer gene polymorphisms for certain proinflammatory cytokines and with low producer gene polymorphisms of certain antiinflammatory cytokines. DNA polymorphisms were investigated using sequence-specific primer (SSP)-polymerase chain reaction (PCR). Results demonstrated that SIDS and controls did not differ significantly with respect to genotype distributions for IL-4 -590 (chi(2) test, p = 0.164), IFN- gamma +874 (p = 0.050), or TGF-beta1 +869 (p = 0.322). However, significant associations with SIDS were seen for genotypes of VEGF -1154 (p = 0.005) and IL-6 -174 (p = 0.018). Comparison of allele frequencies for these cytokine genes between SIDS and control groups reflected the genotype data. Allele frequencies that did not demonstrate significant differences between test groups were IL-4 -590*T (chi2, p = 0.104), IFN- gamma +874*A (p = 0.052), and TGF-beta1 +869*C (p = 0.468). Those demonstrating significant differences between SIDS and control groups were VEGF -1154*A (p= 0.002, OR = 2.94, CI 1.46-6.02) and IL-6 -174*G (p= 0.034, OR = 2.18 CI 1.05-4.56). Thus, there are associations between SIDS and particular polymorphisms of VEGF and IL-6 cytokine genes in addition to those previously found in Manchester with another cohort of samples for the antiinflammatory cytokine IL-10. Moreover, these gene polymorphism associations suggest that the causation of SIDS is related to both fetal lung development and a child's innate ability to mount an inflammatory response to infection.

Evaluation of cytokine genetic polymorphisms in adult patients with common variable immunodeficiency: A single-center study.

Common variable immunodeficiency (CVID) is a heterogeneous disease characterized by impaired B-cell differentiation and maturation accompanied with the defective antibody production. Several investigators addressed the possibility that disturbed cytokine production of TNF, IL-6, IFN-γ and IL-10, among a variety of others, may be implicated in CVID. The aim of this study was to test the hypothesis that genetic polymorphisms involving TNF (-308G/A), IFNG (+874 T/A), IL10 (-1082G/A, -819T/C and -592A/C), and IL6 (-174G/C) cytokine genes might contribute to susceptibility to CVID. Thirty five patients with CVID and 250 healthy controls were genotyped for indicated single nucleotide polymorphisms (SNP) in TNF, IL6, IFNG and IL10 using Taqman-based assays. CVID patients had significantly higher frequency of TNF A allele and AA genotype than in healthy subjects (p=0.006; OR=2.27; 95%CI=1.24-4.17 and p=0.038, OR=15.64; 95%CI=1.38-177.20, respectively). In addition, the frequency of GG genotype was significantly higher in healthy controls than in patient group (p=0.019, OR=0.43, 95%CI=0.21-0.89). Genetic analysis of IL6 SNP showed that allele G confers increased risk for CVID (p=0.037, OR=1.78, 95% CI=1.03-3.08) while IFNG allele T was associated with splenomegaly in CVID (p=0.032; OR=2.86; 95% CI=1.08-7.56). We observed no association between genotypes, alleles and haplotypes of IL-10 gene and CVID or its clinical complications. In conclusion, our results indicated association between CVID and cytokine gene polymorphisms -308G/A TNF and -174G/C IL6. In addition, we demonstrated that splenomegaly, one of the most common complications in this disease, is associated with +874T/A IFNG polymorphism. These findings add further support to the notion that cytokines may play significant role in pathogenesis of this primary antibody deficiency. However, further investigation that would involve a larger study group of CVID patients is warranted to confirm our findings.

The importance of MDR1 gene polymorphisms for tacrolimus dosage.

Polymorphisms of the multi drug resistance (MDR1) gene cause variability in P-glycoprotein mediated metabolism of tacrolimus. The aim of this study was to examine the relationship between MDR1 gene single nucleotide polymorphisms (SNPs) and their haplotypes with dosage of tacrolimus in kidney transplant recipients who were cytochrome (CYP) 3A5*3 homozygotes. This study included 91 kidney transplant recipients followed two years after transplantation. Detection and analysis of MDR1 gene polymorphisms in positions C1236T, G2677T/A and C3435T were performed using PCR method. Patients with variant alleles for SNPs G2677T/A and C3435T required higher doses of tacrolimus and had a lower level/dose (L/D) ratio than patients with wild alleles or heterozygotes. That difference was the most obvious for SNP G2677T/A where TT homozygotes required significantly higher doses of tacrolimus during whole follow-up. Their L/D was significantly lower in the first month after transplantation. Recipients with CTT/TTT haplotype also had lower L/D than those with CGC/TTT and CGC/CGC, significantly in the 10th and 20th days after transplantation respectively (p<0.05). Our results demonstrate that TT homozygotes at positions G2677T/A and C3435T required a higher tacrolimus dose than those with wild alleles or heterozygotes. It may be helpful in the prevention of tacrolimus nephrotoxicity early after transplantation.

Prediction of Warfarin Dose in Pediatric Patients: An Evaluation of the Predictive Performance of Several Models.

OBJECTIVES: The objective of this study was to evaluate the performance of pediatric pharmacogenetic-based dose prediction models by using an independent cohort of pediatric patients from a multicenter trial. METHODS: Clinical and genetic data (CYP2C9 [cytochrome P450 2C9] and VKORC1 [vitamin K epoxide reductase]) were collected from pediatric patients aged 3 months to 17 years who were receiving warfarin as part of standard care at 3 separate clinical sites. The accuracy of 8 previously published pediatric pharmacogenetic-based dose models was evaluated in the validation cohort by comparing predicted maintenance doses to actual stable warfarin doses. The predictive ability was assessed by using the proportion of variance (R(2)), mean prediction error (MPE), and the percentage of predictions that fell within 20% of the actual maintenance dose. RESULTS: Thirty-two children reached a stable international normalized ratio and were included in the validation cohort. The pharmacogenetic-based warfarin dose models showed a proportion of variance ranging from 35% to 78% and an MPE ranging from -2.67 to 0.85 mg/day in the validation cohort. Overall, the model developed by Hamberg et al showed the best performance in the validation cohort (R(2) = 78%; MPE = 0.15 mg/day) with 38% of the predictions falling within 20% of observed doses. CONCLUSIONS: Pharmacogenetic-based algorithms provide better predictions than a fixed-dose approach, although an optimal dose algorithm has not yet been developed.

The relative importance of cytokine gene polymorphisms in the development of early and late acute rejection and six-month renal allograft pathology.

BACKGROUND: Acute rejection episodes and 6-month protocol biopsy acute pathology are highly correlated with long-term outcomes in renal transplant recipients. Recurrent, vascular, and late rejections are particularly deleterious. METHODS: We determined the relative contribution of human leukocyte antigen matching, cytokine genotypes, delayed graft function (DGF), and baseline immunosuppression to the development of acute rejection and allograft pathology in 118 renal transplant recipients. RESULTS: Multivariate logistic regression modeling demonstrated that the adjusted odds ratio and 95% confidence interval for recurrent (> or =2) early rejections (0-3 months) increased linearly for high (H) > intermediate (I) > low (L) interferon-gamma (1.8; 1.1-3.2) and tumor necrosis factor (TNF)alpha (3.0; 1.3-6.9) genotype, whereas every 1 microg/L increase in the cyclosporine A level was protective (0.991; 0.984-0.999). The odds ratio for recurrent late rejections (4-6 months) increased for H > I > L TNFalpha (5.1; 1.8-14.7) genotype and DGF (7.1; 1.6-30.2), whereas H > I/L transforming growth factor-beta1 genotype decreased the relative risk (0.09: 0.02-0.49). Vascular rejection was only predicted by H > I > L TNFalpha phenotype (3.0; 1.2-7.9). The odds ratio for the 6-month Banff Acute Score (6A > or= 4) increased for H > I > L TNFalpha (2.7; 1.1-6.7) and interleukin-10 (3.4; 1.2-6.2) genotype, and DGF (3.4; 1.1-11.5). Treatment of early subclinical rejection decreased the relative risk (0.20; 0.07-0.62). CONCLUSIONS: High transforming growth factor-beta1 producer phenotype seems to be protective against acute inflammation, whereas H and I interferon-gamma, TNFalpha, and interleukin-10 producer genotypes correlate with adverse outcomes. Cytokine genotyping identifies individuals who may benefit from more intensive surveillance and treatment posttransplant.

Interleukin 6 G-174C polymorphism influences outcome following coronary revascularization surgery.

BACKGROUND: Levels of the proinflammatory cytokine interleukin 6 (IL-6) increase after surgery. The functional polymorphism in the IL-6 promoter region, G-174C, is associated with an increased risk of coronary heart disease. We investigated the genetic predisposition in IL-6 response to coronary revascularization and studied the association between the G-174C polymorphism, IL-6 levels, and clinical outcomes of surgery. METHODS: DNA was obtained from 96 consecutive patients who underwent elective coronary revascularization. Patients were genotyped for the IL-6 G-174C polymorphism by means of sequence-specific primer-polymerase chain reaction analysis. IL-6 levels were measured with an enzyme-linked immunosorbent assay on serum samples taken 3 hours postoperatively. IL-6 levels and genotypes (CC, CG, and GG) were correlated with perioperative clinical data. RESULTS: The prevalences of the CC, CG, and GG IL-6 -174 genotypes were 8%, 54%, and 38%, respectively. Patients homozygous for the C allele had higher circulating levels of IL-6 postoperatively than the patients with the CG and GG genotypes (P = .09). Patients homozygous for the G allele had a significantly lower incidence of postoperative atrial fibrillation (P = .032) and a shorter hospital stay (P = .005). This result remained statistically significant following risk stratification. The severity of coronary artery disease and a higher number of bypass grafts were associated with a significant increase in IL-6 level postoperatively (P = .028, and P = .005, respectively). Higher levels of IL-6 were associated with increased blood loss postoperatively (P = .016). CONCLUSIONS: The C allele is associated with higher postoperative IL-6 levels and a less favorable clinical outcome. The G-174C polymorphism is related to the outcome after coronary revascularization.

A study of five human cytokine genes in human essential hypertension.

With a view to evaluating the putative involvement of cytokine gene variants in human essential hypertension, we carried out an association (case-control) study on 174 unrelated nationals (81 hypertensives and 93 normotensives) from the Abu Dhabi Emirate (UAE), a genetically homogeneous population also characterised by the absence of traditional confounding factors such as alcohol consumption and smoking. To that end, we targeted our investigation to five candidate gene loci-transforming growth factor beta1 (TGF-beta1), interferon gamma (IFN-gamma), epidermal growth factor (EGF), interleukin-1 beta (IL-1beta) and tumour-necrosis factor (TNF-alpha) genes. We investigated the distribution of genotypes and alleles of the six following dimorphic variants: TGF-beta1(*)10(T>C) and TGF-beta1(*)25(G>C), located at codons 10 and 25, respectively, of TGF-beta1; T874A in intron 1 of IFN-gamma; G61A in exon 1 of EGF; TaqI dimorphism at +3962 (exon 5) of IL-1beta; and -308A>G in the promoter of TNF-alpha. These six bi-allelic markers were visualised by methods based on the techniques of amplification refractory mutation system-polymerase chain reaction (for TGF-beta1, IFN-gamma, EGF and TNF-alpha) and by polymerase chain reaction-TaqI restriction endonuclease analysis in the case of IL-1beta. In each of the two groups (normotensives and hypertensives), genotype frequencies of all six markers occurred in Hardy-Weinberg proportions. There were, however, no statistical differences in the allele and genotype frequencies of any of the six markers between the two groups of subjects: TGF-beta1(*)10C frequencies were 0.46 and 0.49 (chi(2)=0.61; 2 d.f.; P=0.74) and TGF-beta1(*)25C were 0.07 and 0.08 (chi(2)=0.61; 2 d.f.; P=0.74) amongst normotensives and hypertensives, respectively; p(IFN-gamma(*)A874) were 0.41 in normotensives versus 0.46 in hypertensives (chi(2)=3.07; 2 d.f.; P=0.22); p(EGF (*)G61) were 0.51 versus 0.58 (chi(2)=1.76; 2 d.f.; P=0.41); p[IL-1beta (*)TaqI(+)] were 0.43 versus 0.36 (chi(2)=2.08; 2 d.f.; P=0.35); and p(TNF-alpha(*)-308G) were 0.80 versus 0.85 (chi(2)=1.29; 2 d.f.; P=0.53). There was also no difference in distribution and frequencies of haplotypes constructed with combinations of TGF-beta1(*)10(T>C) and TGF-beta1(*)25(G>C) sites. However, although they do not reach statistical significance (which may be due to the relatively restricted number of subjects included in this study), the distribution differences (in normotensives and hypertensives) observed in the cases of EGF and TNF-alpha reflect trends that could be expected from a mechanistic explanation of the pathways that underlie the patho-physiology of hypertension.

TNF, IL12B, and IFNG Gene Polymorphisms in Serbian Patients with Psoriasis.

BACKGROUND: Psoriasis is a common chronic inflammatory skin disease with a strong genetic basis. Cytokines such as tumor necrosis factor alpha (TNF-α), interleukins (ILs) such are IL-12 and IL-23, and interferon gamma (IFN-γ) are released from various inflammatory and resident cells, and have been implicated in the initiation/maintenance of inflammation. Certain alleles of the aforementioned cytokines may be associated with disease susceptibility/severity. OBJECTIVE: To investigate the association of three common functional gene polymorphisms, namely TNF -308 G/A (rs1800629), IL12B (encoding the p40 subunit of IL-12/23) +1188 A/C (rs3212227), and IFNG +874 T/A (rs2430561) with psoriasis development and severity in Serbian patients. METHODS: We genotyped 130 patients with psoriasis (26 of whom also had psoriatic arthritis) and 259 controls; rs1800629 and rs3212227, and rs2430561, by real-time PCR assay. RESULTS: The TNF GG genotype was detected at a higher frequency in patients with psoriasis compared to control subjects (OR, 1.420; 95% CI, 0.870~2.403) without statistical significance (p=0.191). Lack of the TNF G allele was associated with lower psoriasis severity (p=0.007). The IL12B AC genotype was underrepresented in the patients with psoriatic arthritis compared to healthy subjects (OR, 0.308; 95% CI, 0.090~1.057; p=0.049). The distribution of the rs2430561 allele and genotype frequencies was similar between patients with psoriasis and controls. CONCLUSION: Our study demonstrates an effect of the rs1800629 on psoriasis severity, and a marginal impact of the rs3212227 on susceptibility to psoriatic arthritis. Collectively, our results obtained in a Serbian cohort expand current knowledge regarding individual predisposition to psoriatic disease.