Cytokine gene polymorphism and heart transplant rejection

TNF-α -308A/G SNP association with kidney allograft rejection in Algerian population: A retrospective case-control study

No consensus has been reached regarding the association beween the -308A/G single nucleotide polymorphism (SNP) in the tumor necrosis factor-α gene (TNFA) and kidney allograft rejection (KAR). Our retrospective case-control study aimed to assess the association of the SNP with KAR in Algerian patients who underwent kidney transplantation. The study enrolled 313 Algerian patients: 58 kidney-transplant recipients without rejection events (PWoR); 58 kidney-transplant recipients with at least one rejection event, with or without graft loss (PWR); and 197 healthy individuals (HI). The TNFA -308A/G SNP was genotyped using a real-time polymerase chain reaction. The results demonstrated that, the frequencies of TNFA -308A allele and AA genotype were higher in the PWR than in the HI groups (p = 0.001, OR = 2.26, CI = 1.33-3.77 and p = 0.0004, OR = 5.53, CI-1.89-16.6, respectively). Furthermore, the frequencies were higher among the PWR than among the PWoR groups (p = 0.001, OR = 3.29, CI = 1.56-7.21 and p = 0.0006, OR = 28.26, CI = 1.62-493.2, respectively), particularly among PWR patients with de novo anti-human leukocyte antigens (HLA) antibodies (PG-a-HLA-Ab). However, the frequency of TNFA -308G allele was lower in the PWR group than in the PWoR group (p = 0.001, OR = 0.3, CI = 0.1-0.64) and the HI group (p = 0.001, OR = 0.44, CI = 0.27-0.44). Our results suggest an association of the TNFA -308A/G alleles with KAR in Algerian patients who underwent kidney transplantation. Carriers of TNFA -308A allele who have PG-a-HLA-Ab might have a higher risk, whereas TNFA -308G allele carriers could have a lower risk of KAR. Thus, therapeutic strategies can be adapted to minimize KAR risk in patients who have a genetic proclivity for increased pro-inflammatory TNF-α activity.

Impact of donor blood type on outcomes after prolonged allograft ischemic times

OBJECTIVE

The study objective was to determine the influence of allograft ischemic time on heart transplant outcomes among ABO donor organ types given limited prior reports of its survival impact.

METHODS

We identified 32,454 heart transplants (2000-2016) from the United Network for Organ Sharing database. Continuous and categoric variables were analyzed by parametric and nonparametric testing. Survival was determined using log-rank or Cox regression tests. Propensity matching adjusted for preoperative variables.

RESULTS

By comparing allograft ischemic time less than 4 hours (n = 6579) with 4 hours or more (n = 25,875), the hazard ratios for death at 15 years after prolonged ischemic time (≥4 hours) for blood types O, A, B, and AB were 1.106 (P < .001), 1.062 (P < .001), 1.059 (P = .062), and 1.114 (P = .221), respectively. Unadjusted data demonstrated higher mortality for transplantation of O versus non-O donor hearts for ischemic time 4 hours or more (hazard ratio, 1.164; P < .001). After propensity matching, O donor hearts continued to have worse survival if preserved for 4 hours or more (hazard ratio, 1.137, P = .008), but not if ischemic time was less than 4 hours (hazard ratio, 1.042, P = .113). In a matched group with 4 hours or more of ischemic time, patients receiving O donor organs were more likely to experience death from primary graft dysfunction (2.5% vs 1.7%, P = .052) and chronic allograft rejection (1.9% vs 1.1%, P = .021). No difference in death from primary graft dysfunction or chronic allograft rejection was seen with less than 4 hours of ischemic time (P > .150).

CONCLUSIONS

Compared with non-O donor hearts, transplantation with O donor hearts with ischemic time 4 hours or more leads to worse survival, with higher rates of primary graft dysfunction and chronic rejection. Caution should be practiced when considering donor hearts with the O blood type when anticipating extended cold ischemic times.

Cytokine gene polymorphisms among North Indians: Implications for genetic predisposition?

Variations in the production and activity of cytokines influence the susceptibility and/or resistance to various infectious agents, autoimmune diseases, as well as the post-transplant engraftment/ rejection. Differences in the production of cytokines between individuals have been correlated to single nucleotide polymorphisms (SNPs) in the promoter, coding or non-coding regions of cytokine genes. The present study aimed at understanding distribution of cytokine gene variants among HIV seropositive subjects including HIV + TB+ subjects of Indian origin. Our findings indicate significant association of pro-inflammatory (IL2, IFN-γ, TNF-α) and anti-inflammatory cytokine gene variants (IL4, IL10) with the risk to acquire the HIV infection and development of AIDS related illness in Indian population. Since distribution of genetic polymorphisms varies significantly across different populations, different genotypes might exhibit different disease-modifying effects. An understanding of the immunogenetic factors or AIDS restriction genes is important not only for elucidating the mechanisms of disease pathogenesis but also for vaccine design and its application.

Functionality and opposite roles of two interleukin 4 haplotypes in immune cells

Cytokines expression can be influenced by polymorphisms in their respective coding genes. We associated the CTI/TTD haplotype (Hap-1) and TCI/CCI haplotype (Hap-2) in the IL4 gene formed by the -590, +33 and variable number of tandem repeat polymorphisms with the severity of chronic periodontitis in humans. The functionality of these IL4 haplotypes in the response of immune cells to phorbol 12-myristate 13-acetate (PMA) with Ionomycin and IL-1β (as inflammatory stimuli) was evaluated. Gene expression (quantitative real-time PCR), profile of secreted cytokines (multiplex) and phenotypic polarization of T cells (flow cytometry) were the outcomes assessed. Green fluorescent protein reporter plasmid constructs containing specific IL4 haplotype were transiently transfected into JM cells to assess the influence of the individual haplotypes on promoter activity. In response to inflammatory stimuli the immune cells from Hap-1 haplotype had increased expression of anti-inflammatory IL4; conversely, the Hap-2 haplotype showed higher levels of pro-inflammatory cytokines. The haplotype CTI proved to be the most important for the regulation of IL4 promoter, regardless of the nature of the inflammatory stimulation; whereas the polymorphism in the promoter region had the least functional effect. In conclusion, IL4 haplotypes studied are functional and trigger opposite immune responses: anti-inflammatory (Hap-1) and pro-inflammatory (Hap-2). In addition, we identified the CTI haplotype as the main responsible for the regulation of IL4 transcriptional activity.

TGF-β1 gene - 509C > T promoter polymorphism modulates TGF-β1 levels in hepatitis E patients

Elevated levels of transforming growth factor-β1 (TGF-β1) and its positive correlation with Foxp3 expression in hepatitis E patients have indicated involvement of TGF-β1 in hepatitis E pathogenesis. The current study determined polymorphisms in TGF-β1 gene, plasma TGF-β1 levels and T effector (Teff) cell proliferation and explored their association in a case control study. Polymorphisms in three selected sites (- 509C > T, + 869T > C and + 915G > C) of TGF-β1 gene by PCR & restriction fragment length polymorphism methods, plasma TGF-β1 quantitation by ELISA and Teff (CD4 + CD25 -) cell proliferation by CFSE method were carried out in 277 hepatitis E patients (HE) with self-limiting infection and 233 ethnically matched healthy controls (HCs) from western India. Frequency of CT genotype of - 509C > T site was significantly higher in hepatitis E patients compared to healthy controls (p = 0.017; OR 1.53, 95% CI 1.07-2.17). Plasma TGF-β1 levels were significantly higher in HE compared to HCs. TGF-β1 level of patient group having CT genotype of - 509C > T site was significantly higher compared to those having CC or TT genotypes. Teff cell proliferation was negatively correlated with plasma TGF-β1 levels in HE patients (r = - 0.568; p = 0.014). Influence of TGF-β1 promoter (- 509C > T) polymorphism on plasma TGF-β1 levels and inverse correlation of Teff cell proliferation with plasma TGF-β1 levels in self-limiting hepatitis E patients suggest key role of TGF-β1 in augmentation of reported T regulatory cell mediated pathogenesis in hepatitis E.

Association of cytokine/costimulatory molecule polymorphism and allograft rejection: a comparative review

One reason for genetic variations among human individuals is SNP which may confer diverse disease susceptibility or resistance in a population. Genetic variations in a key immunoregulatory agent can manifest various immunological responses, such as graft rejection. In fact, the outcome of organ transplantation can be impacted by several genetic causes including polymorphisms in genes encoding cytokines and costimulatory molecules in the donor or recipient. Thus, it can be helpful to contemplate the SNPs relating to these immunological determinants in order to achieve an improved transplantation therapy.

HLA variants related to primary sclerosing cholangitis influence rejection after liver transplantation

AIM: To investigate influence of human leukocyte antigen (HLA) and killer immunoglobuline-like receptor (KIR) genotypes on risks of acute rejection (AR) after liver transplantation (LTX).

METHODS: In this retrospective study we included 143 adult donor-recipient pairs with a minimum of 6 mo follow-up after LTX for whom DNA was available from both donor and recipients. Clinical data, all early complications including episodes and severity of AR and graft/patient survival were registered. The diagnosis of AR was based on clinical, biochemical and histological criteria. All suspected episodes of AR were biopsy confirmed. Key classical HLA loci (HLA-A, HLA-B, HLA-C and HLA-DRB1) were genotyped using Sanger sequencing. 16 KIR genes were genotyped using a novel real time PCR approach which allows for determination of the diploid copy number of each KIR gene. Immunohistochemical staining for T (CD3), B (CD20) and natural killer (NK) cells (CD56 and CD57) were performed on liver biopsies from 3 different patient groups [primary sclerosing cholangitis (PSC), primary biliary cirrhosis and non-autoimmune liver disease], 10 in each group, with similar grade of AR.

RESULTS: Fourty-four (31%) patients were transplanted on the basis of PSC, 40% of them had AR vs 24% in the non-PSC group (P = 0.04). No significant impact of donor-recipient matching for HLA and KIR genotypes was detected. In the overall recipient population an increased risk of AR was detected for HLA-B*08 (P = 0.002, OR = 2.5; 95%CI: 1.4-4.6), HLA-C*07 (P = 0.001, OR = 2.4; 95%CI: 1.4-4.0) and HLA-DRB1*03 (P = 0.03, OR = 1.9; 95%CI: 1.0-3.3) and a decreased risk for HLA-DRB1*04 (P = 0.001, OR = 0.2; 95%CI: 0.1-0.5). For HLA-B*08, HLA-C*07 and DRB1*04 the associations remained evident in a subgroup analysis of non-PSC recipients (P = 0.04, P = 0.003 and P = 0.02, respectively). In PSC recipients corresponding P values were 0.002, 0.17 and 0.01 for HLA-B*08, HLA-C*07 and DRB1*04, respectively. A dosage effect of AR prevalence according to the PSC associated HLA alleles was also notable in the total recipient population. For HLA-B*08 the frequency of AR was 56% in HLA-B*08 homozygous recipients, 39% in heterozygous recipients and 21% in recipients lacking HLA-B*08 (P = 0.02). The same was observed for the HLA-C*07 allele with AR in 57%, 27% and 18% in recipients being homozygous, heterozygous and lacking HLA-C*07 respectively (P = 0.003). Immunohistochemical analysis showed similar infiltration of T, B and NK cells in biopsies with AR in all three groups.

CONCLUSION: We found significant associations between the PSC-associated HLA-B*08, HLA-C*07, HLA-DRB1*03 and HLA-DRB1*04 alleles and risk of AR in liver transplant recipients.

Genetic and genomic approaches to the detection of heart transplant rejection

Since Christiaan Barnard performed the first heart transplant in 1967, over 100,000 heart transplants have been performed worldwide. As was true then, rejection remains the major threat to the function and survival of the allograft. The development of the endomyocardial biopsy as a means to monitor for rejection has allowed heart transplantation to thrive as a therapy for patients with end-stage heart disease. The need for a noninvasive method of rejection surveillance led to the development of the first genetic test for allograft rejection, the AlloMap^®. In this article, after presenting the pathological and clinical features of cardiac allograft rejection, the authors discuss the development and application of gene-expression testing for the detection of cardiac allograft rejection. We then explore emerging 'omic' approaches that will be the rejection detection methods of the future.

Role of interleukin 10 transcriptional regulation in inflammation and autoimmune disease

Interleukin 10 (IL-10) is a cytokine with potent anti-inflammatory properties that plays a central role in limiting host immune response to pathogens, thereby preventing damage to the host and maintaining normal tissue homeostasis. Dysregulation of IL-10 is associated with enhanced immunopathology in response to infection as well as increased risk for development of many autoimmune diseases. Thus a fundamental understanding of IL-10 gene expression is critical for our comprehension of disease progression and resolution of host inflammatory response. In this review, we discuss modes of regulation of IL-10 gene expression in immune effector cell types, including signal transduction, epigenetics, promoter architecture, and post-transcriptional regulation, and how aberrant regulation contributes to immunopathology and disease progression.

Interleukin-10-1082G/A polymorphism and acute liver graft rejection: A meta-analysis

AIM: To investigate the association between interleukin (IL)-10-1082 (G/A) promoter polymorphism and acute rejection (AR) in liver transplant (LT) recipients.

METHODS: Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure, and Chinese Biomedicine Databases. Summary odds ratios (ORs) and 95% CIs for IL-10-1082 G/A polymorphism and AR were calculated in a fixed- and a random-effects model as appropriate.

RESULTS: This meta-analysis included seven case-control studies, which comprised 652 cases of LT recipients in which 241 cases developed AR and 411 cases did not develop AR. Overall, the variant A allele was not associated with AR risk when compared with the wild-type G allele (OR = 0.94, 95% CI: 0.64-1.39). Moreover, similar results were observed when the AA genotype was compared with the AG/GG genotype (OR = 1.05, 95% CI: 0.55-2.02). When stratifying for ethnicity, no significant association was observed among either Caucasians or Asians. Because only one study was performed in Asian patients, the result of subgroup analysis by ethnicity would not be reliable for Asians. Limiting the analysis to the studies with controls in the Hardy-Weinberg equilibrium, the results were persistent and robust. No publication bias was found in the present study.

CONCLUSION: This meta-analysis suggests that IL-10-1082 G/A polymorphism may be not associated with AR risk in LT recipients among Caucasians.

Immune factors influencing ethnic disparities in kidney transplantation outcomes

An influence of ethnicity on the outcomes of kidney transplant recipients has been recognized for several decades. Both immune and nonimmune factors have been explored as potential explanations. Most studies have focused on the inferior outcomes of African-Americans. As a group, African-Americans differ from Caucasians with respect to a number of measurable components of the alloimmune response, including the T-cell repertoire and the expression and function of costimulatory molecules and various cytokines and chemokines. In general, these differences suggest that African-Americans may be high immune responders. However, no single difference in any of these components of alloimmunity satisfactorily explains the disparities in outcomes. It seems probable that some combination of immune factors interacts with nonimmune factors, such as socioeconomic resources, to influence transplant outcomes in a complex manner.

Association between the Interleukin 10-1082G>A polymorphism and coronary heart disease risk in a Caucasian population: a meta-analysis

Interleukin-10 (IL-10) is a cytokine with anti-inflammatory and B-cell-stimulating activity. IL-10 is expressed in human atherosclerotic plaques and studies have shown the involvement of IL-10 in the atherosclerotic process. The IL-10-1082G/A polymorphism is one of the most commonly studied polymorphisms in this gene because of its association with coronary heart disease (CHD) risks, but previous results have been conflicting. We performed a meta-analysis using six eligible case-control studies (including 14 data sets) with a total of 5006 patients and 3968 controls to summarize the existing data on the association between the IL-10-1082G/A polymorphism and CHD risk. Compared with the common IL-10-1082G/A GG genotype, the carriers of variant genotypes (IL-10-1082GA/AA) had a 1.12-fold elevated risk of CHD (95% CI = 1.01-1.23, P = 0.03) under the dominant genetic model, as estimated using a random effect model. The effect of the IL-10-1082G/A polymorphism was further evaluated using stratification analysis. In the three disease of artery studies, with the variant genotypes had a not obvious increased risk of disease of artery (OR = 1.19, 95% CI = 0.98-1.44, P = 0.08) as estimated using a fixed effect model. Similar results were found in the nine myocardial infarction studies (OR = 1.13, 95% CI = 1.00-1.27, P = 0.05). It was also demonstrated that the increased risk of CHD associated with IL-10-1082G/A variant genotypes was more pronounced in Caucasians (OR = 1.12, 95% CI = 1.01-1.23, P = 0.03). Our meta-analysis suggests that the IL-10-1082G/A polymorphism genotypes (GA+AA) might be associated with an increased risk of CHD, especially in Caucasians.

Graft inflammation and histologic indicators of kidney chronic allograft failure: low-expressing interleukin-10 genotypes cannot be ignored

BACKGROUND

Infiltration of inflammatory cells into the renal allograft interstitium is the biologic hallmark of alloimmune responses that leads to tubulointerstitial injury and subsequent interstitial fibrosis and chronic allograft failure. The proliferation, stimulation, and infiltration of these inflammatory cells are governed by various proinflammatory and regulatory cytokines. We assessed whether the differences in the genes encoding cytokines (producing low, moderate, or high expression profiles) may affect the infiltration of inflammatory cells into the renal allograft and the histologic changes characteristics of chronic allograft failure.

METHODS

A total of 218 kidney transplant recipients were genotyped for 15 single-nucleotide polymorphisms located in the gene promoter or exonic regions of 10 different cytokines or their receptors. Six- to 12-month posttransplant surveillance biopsies were scored using 11 individual histologic parameters and the combined grade of interstitial fibrosis and tubular atrophy (IF/TA). B-cell, T-cell, and macrophage infiltrates were quantified by immunostaining.

RESULTS

The low-expressing interleukin (IL)-10 gene promoter genotypes were found significantly associated with high IF/TA grade (IL-10 -819 TT; P=0.035; odds ratio=3.27; 95% confidence interval 1.1-9.8). At individual histologic indices, recipients carrying low-expressing IL-10 genotypes showed 2.5-fold higher scores for interstitial fibrosis, inflammation, and tubular atrophy. High infiltration of T cells and macrophages but not B cells into the renal allograft interstitium was found strongly associated with the carriage of low-expressing IL-10 genotypes.

CONCLUSIONS

The results suggest that renal transplant recipients genetically predisposed to low expression of the regulatory cytokine IL-10 are more susceptible to high grades of IF/TA scores, graft inflammation, and high influx of inflammatory cells into the graft interstitium.

Cytokine Genotype Polymorphisms in Breast Carcinoma: Associations of TGF-β1 with Relapse

Markers of angiogenesis, cell proliferation, and cytokine regulation are associated with the development and course of autoimmune and malignant diseases. We investigated associations between cytokine production genotypes in breast cancer patients compared with controls and explored associations with known prognostic indices and relapse status. Eighty-eight females with breast carcinoma (BC) were studied in this case-control study comparing the cytokine genotypes of TNF-alpha TGF-beta1, IL-10, IL-6, and IFN-gamma with controls. Cytokine polymorphisms were identified by sequence-specific primers for codons, introns, or promoters regulating cytokine production. Patient characteristics, such as estrogen and progesterone receptor status, DNA ploidy, Her-2 neu expression, lymph node involvement, tumor size, and relapse status were evaluated. Cytokine genotypes were not associated with breast cancer compared with controls. Correlations between TGF-beta1 high-production genotypes and greater than four positive lymph nodes (OR=2.3; p=ns) and TNF-alpha high-production genotype and the mean level of estrogen receptor expression (66 +/- 24 vs. 34 +/- 36, p=0.016) were identified. The median patient follow-up interval from diagnosis to evaluation was 50.1 months (range 13-387 months). Relapse status was known for 84 of the patients. The odds of relapse in TGF-beta1 codon 10 CC genotypes was 2.81 times that in TGF-beta1 high-production genotypes (OR=2.81; 95% CI for OR: 1.0, 7.8; p=0.04). Mean progesterone receptor expression was decreased in relapsed patients (40.9 +/- 29.9% vs. 23.1 +/- 24.5, p=0.05). The other cytokine genotypes studied (IL-10, IL-6, IFN-gamma, and TNF-alpha production were not associated with breast cancer overall or relapse status. In this study, TGF-beta1 low-production genotypes (TGF-beta1 10 CC) were associated with an increased odds of disease relapse. This finding should be confirmed in a longitudinal study to further investigate the regulatory function of cytokine production as a prognostic indicator of relapse.

Clinical impact of cytokine and growth factor genetic polymorphisms in thoracic organ transplantation

Demographic and clinical risk factors may only partially predict short- and long-term outcomes after thoracic transplantation. The interindividual variability seen in rejection profiles could be related to the recipient's or donor's genetic background. Rejection, either acute or chronic, elicits an alloimmune response that involves a complex network of cytokines, growth factors, adhesion molecules, and other molecules, which may modulate the immune response toward rejection or, conversely, mediate graft acceptance. Herein, the authors discuss the current evidence regarding the importance of genetic polymorphisms as independent predictors of allograft outcome. They believe that pretransplant genotype profiling of patients, in combination with other relevant clinical information, might be useful to predict the risk for posttransplant adverse events and also to facilitate the implementation of individualized immunosuppression.

The impact of immune gene polymorphisms in kidney and liver transplantation

Since the completion of the Human Genome Project, it has become clear that genetic variation exists among individuals that can affect functional gene expression. This finding raises the possibility that differences in genetic phenotypes may account for the interindividual responses seen in the context of the alloimmune response. This review highlights studies examining the relative role of immunologic gene polymorphism in the context of renal and liver transplant outcomes (eg, acute rejection and graft survival). Furthermore, it examines the limitations and pitfalls in the study designs and concludes with the potential of single nucleotide polymorphism analysis in the future care of transplant recipients.

Polymorphisms of cytokine and innate immunity genes and GVHD

In the last 10 years, non-HLA genotypes have been investigated for their potential roles in the occurrence and severity of graft-versus-host disease (GVHD) as well as for their contribution to overall transplant-related mortality, infectious episodes, and overall survival. This chapter will review the latest results of cytokine gene polymorphisms between patient and donor which may cause the production of high or low levels of cytokines during the three-stage process of the GVHD 'cytokine storm'. More recent investigations into innate immunity and the interaction with subsequent downstream cytokine production and ultimate tissue damage are discussed. The potential of these non-HLA genetics to aid in predicting GVHD and post-transplant survival and the relevance of this information to the clinic are reviewed.

Effect of cytokine and pharmacogenomic genetic polymorphisms in transplantation

Consolidating the information that we have on pharmacogenetics and on cytokine genetics to produce patient-oriented individualized drug regimens is an important challenge in transplantation medicine. Using a multi-variant approach based on genetic profile and other relevant clinical factors a score system may be developed to predict the severity of rejection, infection, or other complications associated with transplantation. The ultimate goal of these studies is to improve patient outcome through individualized drug regimens.

Genetic polymorphisms and the fate of the transplanted organ

There has been an abundance of publications describing genetic variability in molecules affecting innate and adaptive immunity, pharmacogenetics, and other nonimmunological factors like the renin-angiotensin aldosterone system, coagulation, and fibrosis markers. Studies indicated some associations between polymorphisms in these candidate genes with outcomes in organ transplantation and underlined a potential role of genetic variability in transplantation. To be clinically applicable, large prospective studies must be performed to better define the potential benefits of genotyping on these genetic markers and clinical outcomes. The purposes of this review are to summarize recent data describing associations of polymorphisms in both immunological and nonimmunological molecules with transplant outcomes, with a particular emphasis on renal transplantation, and discuss limitations and clinical implications.

A pilot case-control association study of cytokine polymorphisms in Brazilian women presenting with HPV-related cervical lesions

OBJECTIVE AND STUDY DESIGN

A case-control study was conducted on 42 Brazilian women presenting with human papilloma virus (HPV) infection and cervical lesion and 87 HPV-negative women to evaluate single nucleotide polymorphisms observed in TNF-alpha, TGF-beta, IL-10, IL-6, and IFN-gamma genes.

RESULTS AND CONCLUSION

No significant association was observed on the cytokine polymorphisms analyzed in this series. Larger studies using cytokine polymorphisms may be useful for providing further information regarding their influence or not in HPV-related cervical lesions.

High tissue factor-expressing human monocytes carry low surface CD36: application to intersubject variability

BACKGROUND

The 'high and low responder' phenomenon describes an intersubject variability in mononuclear cell (MNC) prothrombotic reactivity to lipopolysaccharide (LPS) stimulation. Because alterations in surface CD36 expression in monocytes were associated with impaired monocyte function, we studied the relationship between the levels of surface CD36 presentation and the prothrombotic reactivity of monocytes from high-responder (HR) and low-responder (LR) individuals.

METHODS AND RESULTS

The relationship between levels of tissue factor (TF) expression and surface CD36 presentation in MNCs from HR individuals (n = 7) and LR individuals (n = 8) was investigated. Resting MNCs from HR individuals contained significantly more TF mRNA but levels of TF antigen and procoagulant activity similar to MNCs from LR individuals. Resting CD14+ MNCs from HR individuals expressed significantly lower surface CD36, as mean fluorescence intensities (MFIs) were 70.4 +/- 6.3 vs. 132.0 +/- 14.5 arbitrary units (AU) in HR and LR individuals, respectively. MFI from surface TF negatively correlated with surface CD36 in the population of resting (r = -0.598, P = 0.031) and LPS-stimulated (r = -0.672, P = 0.009) CD14+ cells. LPS-stimulated MNCs from HR individuals contained significantly more TF in a surface pool (2079 +/- 199 vs. 786 +/- 57 AU) along with higher TF procoagulant activity (57.3 +/- 15.2 vs. 21.1 +/- 4.5 mU 10(6) cells(-1)) as compared with LR individuals. CD14+ MNCs from HR individuals expressed less surface CD36 during a 2-h LPS challenge.

CONCLUSIONS

A novel phenotype of monocytes characterized by high TF and low CD36 presentation could be further developed for use as a marker for detection of HR individuals prone to developing prothrombotic conditions.

Haematopoietic stem cell transplantation: can our genes predict clinical outcome?

Haematopoietic stem cell transplantation (HSCT) is currently the only curative treatment for many patients with malignant and non-malignant haematological diseases. The success of HSCT is greatly reduced by the development of complications, which include graft-versus-host disease (GVHD), relapse and infection. Human leukocyte antigen (HLA) matching of patients and donors is essential, but does not completely prevent these complications; non-HLA genes may also have an impact upon transplant outcome. Polymorphisms within genes that are associated with an individual's capability to mount an immune response to alloantigen and infectious pathogens and/or response to drugs (pharmacogenomics) are all currently being studied for their association with HSCT outcome. This review summarises the potential role of non-HLA polymorphisms in predicting HSCT outcome, from studies on retrospective transplant cohorts of HLA-identical siblings and matched unrelated donors. The clinical relevance and interpretation of non-HLA genetics, and how these could be used alongside clinical risk factors in HSCT, are also discussed.

Impact of serum levels and gene polymorphism of cytokines on chronic hepatitis C infection

The factors leading to clearance or persistent infection of hepatitis C virus (HCV) were not well defined, and the importance of the host immune response has been highlighted. Therefore, the impact of the serum concentration and genetic polymorphism of several cytokines on the outcome of HCV infection warrant additional study. Enzyme-linked immunosorbent assay was employed to measure serum tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-4, and IL-10 concentrations on 72 hepatitis C patients and 180 controls. Furthermore, the association between single nucleotide polymorphism (SNP) of genes of these cytokines and hepatitis C infection was evaluated by polymerase chain reaction- restriction fragment length polymorphism and statistical analysis. These analyzed SNPs of cytokines included TNF-alpha G238A, TNF-alpha G308A, IL-4 C589T, IL-10 A1082G, IL-10 T819C, and IL-10 A592C. Serum levels of TNF-mu alpha, IL-4, and IL-10 were significantly higher in hepatitis C patients than that of controls (P < 0.001). Furthermore, the distribution of TNF-alpha G308A genotypes and alleles, but not others, was statistically different between patients and controls (P < 0.05). These data suggested the distribution of polymorphism at TNF-alpha G308A may be different between normal subjects and patients with chronic infection of hepatitis C.

Risk assessment in haematopoietic stem cell transplantation: Pre–transplant patient and donor factors: non-HLA genetics

Non-HLA genetics involving the study of single-nucleotide polymorphisms (SNPs) and microsatellites of cytokine and cytokine receptor genes, and as well as genes associated with response to infection and therapeutic drugs, are currently being studied for associations with diseases, including autoimmune disease, cancer and solid-organ transplant rejection. This chapter will summarize the potential role of non-HLA genetics in predicting outcome of haematopoietic stem-cell transplantation (HSCT) and how genotyping for non-HLA genes may give insight into the immunobiology of HSCT complications, including GvHD and infectious episodes. Future directions - including the role of pharmacogenomics, use of the research results for individualized medicine, and interpretation of data - will also be discussed.

Frequency distribution of cytokine gene polymorphisms in the healthy North Indian population

The allelic and genotype frequencies corresponding to 22 single nucleotide polymorphisms (SNPs) in 13 cytokine genes interleukin (IL) 1-alpha (T/C -889), IL1-beta (C/T -511, T/C +3962), IL12 (C/A -1188), interferon-gamma (A/T UTR 5644), transforming growth factor-beta (C/T codon 10, G/C codon 25), tumour necrosis factor-alpha (G/A -308, G/A -238), IL2 (T/G -330, G/T +160), IL4 (T/G -1098, T/C -590, T/C -33), IL6 (G/C -174, G/A nt 565), IL10 (G/A -1082, C/T -819, C/A -592), IL1R (C/T pst11970), IL1RA (T/C mspa111100) and IL4RA (G/A +1902) were determined in 130 healthy North Indian subjects. All genomic typings were performed with polymerase chain reaction with sequence-specific assays. An analysis of the allelic and haplotype frequencies in the North Indian population showed a good fit with the Hardy-Weinberg equilibrium for most of the SNPs. The data can be used for anthropological comparisons, as well as for association studies with different diseases and for use in transplant situations involving acute and chronic rejection.

Disparate Distribution of 16 Candidate Single Nucleotide Polymorphisms Among Racial and Ethnic Groups of Pediatric Heart Transplant Patients

BACKGROUND

Allograft failure in African-Americans remains higher than in Caucasians. Single nucleotide polymorphisms (SNPs) have been associated with altered allograft outcomes.

METHODS

In this multi-center study we compared SNP frequencies in 364 pediatric heart recipients from three ethnic/racial groups: Caucasian (n = 243), African-American (n = 39), and Hispanic (n = 82). The target genes were: tumor necrosis factor-alpha, interleukin (IL)-10, IL-6, interferon (IFN)-gamma, vascular endothelial growth factor (VEGF), transforming growth factor-beta1, Fas, FasL, granzyme B, ABCB1, CYP3A5.

RESULTS

Compared to Caucasians, African-Americans exhibited a higher prevalence of genotypes associated with low expression of IFN-gamma (24% vs. 45.7%, P < 0.001) and IL-10 (33% vs. 57.1%, P = 0.052). African-Americans also exhibited an increased prevalence of high IL-6 (82.9% vs. 38.1%; P < 0.001). VEGF -2578 C/C and -460 C/C genotypes were found more frequently in African-Americans and Hispanics as compared to Caucasians (P < 0.001). G/G genotype of Fas and T/T genotype of FasL were expressed more often by African-American recipients. The prevalence of Granzyme B (-295A/G) genotype was differentially distributed in the three groups. Compared with Caucasians, African-Americans were twice as likely to carry the ABCB1 2677 G/G genotype (78.6% vs. 33.7%, P < 0.0025), and they were more frequent carriers of the CYP3A5 *1/*1 genotype (35.7% vs. 0.6% in Caucasians and 7.2% in Hispanics; P < 0.001).

CONCLUSION

African-Americans have a genetic background that may predispose to proinflammatory/lower regulatory environment, reduced drug exposure and immunosuppressive efficacy. In this ongoing multicenter study, these gene polymorphisms differences among ethnic/racial groups are being documented so that therapeutic strategies can be devised to optimize outcomes for pediatric transplant recipients.

The G-308A promoter variant of the tumor necrosis factor-alpha gene is associated with migraine without aura

Migraine is considered to be a polygenic multifactorial disease with various environmental and genetic etiologies. Tumor necrosis factor-alpha (TNF-alpha), a potent immunomodulator and pro-inflammatory cytokine, has been implicated in many pathological processes in brain. The hypothesis of this study was that migraine without aura (MWA) might be associated with TNF-alpha (-308) polymorphism, resulting in increased TNF-alpha production. Genotyping was performed on DNA extracted from peripheral leukocytes by PCR-SSP method in 221 patients with WMA and 183 healthy control subjects from Iranian population. The results showed that the frequency of -308 A variant allele was higher in MWA than in the control group (40.6% versus 22.3%, OR 3.73, 95% CI 2.4-5.82, p<0.0001). TNF-alpha GA heterozygous genotype, high producer, was significantly more prevalent in patients with MWA than controls (74% versus 44.7%, p<0.0001) whilst the low producer GG homozygous genotype was less frequent in patients compared with controls (22.4% versus 55.3%, p<0.0001). The logistic regression analysis showed a significant association for TNF-alpha (-308A) female allele carriers with MWA at reproductive ages (OR 2.56; 95% CI, 1.57-4.16, p<0.0001) when compared with their matched control subjects. In conclusion, this study demonstrates an association of tumor necrosis factor-alpha (-308A) carriage with MWA, suggesting that carrying a high responder TNF-alpha-308A allele may be a genetic factor in increasing the susceptibility to develop MWA.

Genetic markers of treatment response in rheumatoid arthritis

Rheumatoid arthritis patients exhibit a considerable interindividual variability in response to drug treatment. Although many disease-related and demographic factors have been studied to predict treatment outcome, the effective disease-modifying antirheumatic drug (DMARD) therapy is not yet allocated based on factors that predict efficacy. Individual genetic characteristics are thought to play an important role in treatment response; therefore, current research aims to identify these genetic predictors for clinical response. Pharmacogenetic studies are beginning to provide results, which suggests that personalized treatment maximization of DMARD efficacy and minimization of adverse drug reactions are feasible.

Donor-specific Cytotoxic Hyporesponsiveness Associated With High Interleukin-10 Messenger RNA Expression in Cardiac Allograft Patients

BACKGROUND

After transplantation, CD4+CD25+FOXP3+ and interleukin (IL) 10-producing regulatory cells might regulate immune responses toward donor antigens. In this study, we determined whether cardiac allograft recipients show donor-specific hyporesponsiveness and studied the underlying mechanisms.

METHODS

We analyzed the donor-specific T-cell responses by mixed lymphocyte reactions and limiting dilution assays to define whether cardiac allograft recipients (n = 21) show proliferative and cytotoxic hyporesponsiveness to donor antigens long after transplantation (range, 1.5-7 years). The mechanisms controlling immune responses, that is, FOXP3+/GITR+ T cells, and IL-10-producing cells, were studied by quantitative real-time polymerase chain reaction.

RESULTS

In the presence of a proliferative response to donor antigens, no cytotoxic responsiveness could be measured in a number of patients in the absence (73%) and presence of exogenous IL-2 (29%), IL-15 (31%), and IL-15 plus IL2Ralpha blockade (88%). Overall, the cytotoxic response to donor cells was significantly lower than the reactivity to third-party cells after the addition of IL-2 (p = 0.004) and IL-15 plus IL2Ralpha blockade (p < 0.001). After donor stimulation, the peripheral blood mononuclear cells expressed higher messenger RNA (mRNA) levels of IL-10, but not of FOXP3 or GITR, than after third-party stimulation (p = 0.003). Moreover, the IL-10 mRNA expression was inversely correlated with the donor-specific cytotoxic responsiveness (p = 0.01).

CONCLUSIONS

A significant proportion of patients showed donor-specific cytotoxic hyporesponsiveness long after heart transplantation, which was associated with high mRNA levels of IL-10 but not of FOXP3 or GITR. This observation suggests that IL-10-producing cells participate in the donor-specific cytotoxic hyporeactivity.

Cytokine gene polymorphism in Iranian patients with chronic myelogenous leukaemia

Chronic myelogenous leukaemia (CML) is a disorder of the haematopoietic stem cell that results in malignant expansion of myeloid cells with a cytogenetic abnormality, and translocation between chromosomes 9 and 22, known as the Philadelphia chromosome. It has been hypothesized that genetic factors other than histocompatibility disparity may play a role in predisposition to developing CML. In this regard, T helper types 1 and 2 (Th1 and Th2) cytokines and their gene polymorphism seem to be important. Overall expression and secretion of cytokines are dependent, at least in part, on genetic polymorphism (nucleotide variations) within the promoter region or other regulatory sequences of cytokine genes. The majority of polymorphisms described are single nucleotide polymorphism (SNPs). The objective of this study was to analyse the genetic profile of Th1 and Th2 cytokines in 30 Iranian patients with CML and 40 healthy subjects. In the patients and control subjects, the allelic and genotype frequencies were determined for the cytokine genes. All typing were performed with a polymerase chain reaction-sequence-specific primers (PCR-SSP) assay. Allele and genotype frequencies were calculated and compared with those of normal controls. The results showed that the most frequent genotypes in our patients were transforming growth factor (TGF)-beta TG/TG, interferon (IFN)-gamma AT, interleukin (IL)-4 CC at position -590, TT at position -33, and IL-10 ACC/ACC and ATA/ATA. In contrast, the genotypes TGF-beta CG/CG, IL-2 TT at position -330, IL-4 CT at position -590, CT at position -33, and IL-10 GCC/ACC were seen at much lower frequencies. The results suggest that production of TGF-beta in CML patients is higher and production of IL-4 and IL-10 is lower than in normal subjects.

Combined polymorphisms of tumour necrosis factor alpha and interleukin-10 genes in patients with alcoholic hepatitis

OBJECTIVES

The development and progression of alcoholic hepatitis are controlled by an extensive cytokine network which involves pro-inflammatory and anti-inflammatory cytokines. Genetic variations determining production of these cytokines have been described and the susceptibility to the disease may be determined by an imbalance in the expression of several candidate genes.

METHODS

We have studied biallelic single nucleotide polymorphisms at positions (-308) and (-238) in the promoter region of the pro-inflammatory tumour necrosis factor alpha (TNF-alpha) and at positions (-1,082) and (-592) in the promoter of anti-inflammatory interleukin-10 (IL-10) in 134 patients with severe biopsy-proven alcoholic hepatitis and 145 healthy subjects.

RESULTS

The frequency distribution of isolated cytokine genotypes did not differ between the two groups. The combination of at least one A or A allele for TNF-alpha, associated with a TNF-alpha high-producer phenotype, and one A or A allele for IL-10, associated with an IL-10 low-producer phenotype, was less frequent in patients (20.9 vs 33.8%, P=0.016, OR (95% CI)=0.52 (0.30-0.89)). The same combination in patients was associated with a higher risk of septic complications (32.5 vs 16.0%, P=0.031, OR (95% CI)=1.79 (1.07-6.00)) but not with in-hospital mortality.

CONCLUSIONS

We have not found any relationship between the isolated polymorphisms and the risk of alcoholic hepatitis. Moreover, the imbalance between the pro-inflammatory and anti-inflammatory responses leading to high TNF-alpha production and low IL-10 was uncommon in alcoholic hepatitis. However, patients with this particular genotype appeared more susceptible to severe septic complications.

Genetic polymorphisms in patients with myelodysplastic syndrome

Myelodysplastic syndrome (MDS) is a family of clonal disorders characterized by dyshematopoiesis and susceptibility to acute myelogenous leukemia. Tumor necrosis factor-a (TNF-alpha) and transforming growth factor-beta (TGF-beta) are cytokines that play key roles in the pathogenesis of MDS. There have been several reports on the presence of genetic polymorphisms in the DNA sequence encoding the leader sequence of the TGF-beta protein, and in the -308 promoter region of TNF-alpha. The association between TNF-alpha and TGF-beta1 gene polymorphism and the susceptibility to MDS and the progression of the disease was investigated. As compared with healthy control subjects (n = 74), patients with MDS (n = 55) showed no significant deviations in genotype or allele frequencies of TNF-alpha. Similarly, there were no differences in the distribution of TNF-alpha genotypes between the MDS patients with only anemia (mild group) and those with bi- or pancytopenia (severe group). On the other hand the TT homozygosity at codon 10 in exon 1 of TGF-beta1 gene was associated with a severe degree of cytopenia [95% CI OR = 4.889, p = 0.0071]. These findings suggest that the investigated genetic polymorphisms do not predispose to the development of MDS, but that TGF-beta1 gene polymorphism may affect the disease progression.

Leukocyte Suppression is Associated with Improved Clinical Outcomes in Children’s Status after Orthotopic Heart Transplantation

BACKGROUND

Leukocyte suppression is a sequela of immunosuppressive therapy after orthotopic heart transplantation and may result in discontinuation of anti-proliferative agents. Clinical outcomes in this patient population have not been well delineated.

METHODS

This study was a retrospective review of children who underwent orthotopic heart transplantation at our institution from 1986 to 2003. Leukocyte suppression was defined as a white blood cell count <5,000, prompting the withdrawal of anti-proliferative agents. The population was divided into 2 groups, leukosuppressed (LS) and non-leukosuppressed (NLS), and their clinical outcomes were compared.

RESULTS

The study included 109 patients, of which 44 (40%) became leukosuppressed. The 2 groups were similar regarding demographic data and initial management. The LS Group had a significantly decreased incidence of rejection, being 7 times less likely to have recurrent rejection (p = 0.001). The median time to rejection was 0.8 +/- 0.6 years for the NLS Group, whereas the median time to rejection was not yet reached at 17 years for the LS Group. The LS Group also tended toward a decreased incidence of retransplantation or death (p = 0.06). The organ "half-life" in the NLS Group was 7.5 years vs 12.5 years in the LS Group. There was no difference between the 2 groups in regards to other adverse effects of immunosuppression.

CONCLUSIONS

Children who have undergone orthotopic heart transplantation and subsequently become leukosuppressed have a lower incidence of rejection and a tendency toward less organ loss than children who do not become leukosuppressed, without having an increased incidence of adverse side effects.

Lack of association between the TNF-alpha promoter gene polymorphism and susceptibility to B-cell chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukaemia (B-CLL) is a lymphoproliferative disorder characterized by clonal expansion of B lymphocytes. The present study aimed to determine whether there is an association between the polymorphic features located within the promoter/enhancer region of tumour necrosis factor-alpha (TNFA) gene and susceptibility to B-CLL. TNFA (-308 G/A) promoter single nucleotide polymorphism (SNP) was determined by polymerase chain reaction with sequence-specific primers (PCR-SSP) using commercial oligonucleotides. No significant association was found between the distribution of TNFA alleles and B-CLL in Polish patients with B-CLL. Our single centre results were compared with other literature data and combined in a cumulative analysis employing the Mantel-Haenszel method. Among 183 B-CLL patients, 47 (26%) were carrying TNFA*2 allele and this allele was present in 98 out of 348 controls (28%). Also, the results of the Mantel-Haenszel test did not show a significant correlation [Mantel-Haenszel estimate of approximate relative risk (RMH) = 0.86, P = 0.294]. These results suggest that TNFA (-308) alleles are not involved in the predisposition to the development of B-CLL.

Is the association between TNF-alpha-308 A allele and DMT1 independent of HLA-DRB1, DQB1 alleles?

The aim of the study was to assess chosen factors of genetic susceptibility to DMT1: DRB1, DQB1, and TNF-alpha polymorphisms-308 (G/A) in children with DMT1 and their up-to-now healthy siblings. Then we tested whether the association between TNF-alpha genes and DMT1 is independent of HLA. 87 diabetic children, their 78 siblings, and 85 persons from healthy control group were followed up. The highest risk of DMT1 was connected with alleles: DRB1*0401 (OR = 3.39; CI: 1.55-7.41), DRB1*0301 (OR = 2.72; CI: 1.48-5.01), DQB1*0201 (OR = 4.04; CI: 2.17-7.52), DQB1*0302 (OR = 5.08; CI: 2.54-10.14), and TNF-alpha-308 A allele (OR = 2.59; CI: 1.23-5.44). Moreover linkage disequilibrium for TNF-alpha-308 A allele with DRB1*0301 and DQB1*0201 was observed in both diabetic children and their siblings. Diabetic children and their siblings present similar genetic risk factors for DMT1. The association between TNF-alpha-308 A allele and DMT1 is dependent of HLA-DRB1 and DQB1 alleles.