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Significant racial disparity remains in the incidence of unfavorable outcomes following heart transplantation. We sought to determine which pediatric posttransplantation outcomes differ by race and whether these can be explained by recipient demographic, clinical, and genetic attributes. Data were collected for 80 black and 450 nonblack pediatric recipients transplanted at 1 of 6 centers between 1993 and 2008. Genotyping was performed for 20 candidate genes. Average follow-up was 6.25 years. Unadjusted 5-year rates for death (p = 0.001), graft loss (p = 0.015), acute rejection with severe hemodynamic compromise (p = 0.001), late rejection (p = 0.005), and late rejection with hemodynamic compromise (p = 0.004) were significantly higher among blacks compared with nonblacks. Black recipients were more likely to be older at the time of transplantation (p < 0.001), suffer from cardiomyopathy (p = 0.004), and have public insurance (p < 0.001), and were less likely to undergo induction therapy (p = 0.0039). In multivariate regression models adjusting for age, sex, cardiac diagnosis, insurance status, and genetic variations, black race remained a significant risk factor for all the above outcomes. These clinical and genetic variables explained only 8-19% of the excess risk observed for black recipients. We have confirmed racial differences in survival, graft loss, and several rejection outcomes following heart transplantation in children, which could not be fully explained by differences in recipient attributes.

Sjogren Syndrome (SS) is an autoimmune rheumatic disease, whose hallmark is ocular and mouth dryness secondary to autoimmune exocrinopathy. Rarely, SS can affect both peripheral nervous system (PNS) as well as central nervous system (CNS). When CNS is involved, SS is usually diagnosed after patients present with neurologic symptoms. Both ischemic and hemorrhagic stroke can present as first manifestation of primary SS. Stroke is described in literature as a rare entity associated with primary SS, and only few cases were reported. In some cases, CNS involvement was thought to be related to CNS vasculitis, but most of the times remains questionable. We present a rare case of intracranial hemorrhage as first manifestation of primary SS and a review of the pertinent literature.

Background Rejection with hemodynamic compromise (RHC) is associated with high mortality in heart recipients. This study investigates the association between genetic polymorphisms and RHC in pediatric heart recipients. Methods Data from 532 pediatric heart recipients from six centers in the Pediatric Heart Transplant Study were analyzed for time to RHC by recipient race, age at transplantation, and genotype at 13 genetic polymorphisms (TNF-α A-308G, IL-6 G-174C, INF-γ T+874A, IL-10 G-1082A, C-819T, and C-592A; FAS A-670G, FASL C-843T, and ACE I/D; and VEGF A-2578C, C-1451T, C+405G, and -2549 I/D). Results RHC occurred in 126 (23.7%) patients during the study period. Adjusting for age and race, IL-10 G-1082A, FAS A-670G, and ACE I/D genotypes were associated with RHC. IL-10 G-1082A GG genotype was associated with decreased risk of RHC with an adjusted hazard ratio (HR) of 0.49 (95% confidence interval [CI], 0.27-0.90; P=0.020). FAS A-670G AA genotype was associated with increased risk of RHC with an adjusted HR of 1.84 (95% CI, 1.25-2.69; P=0.002). ACE II genotype was associated with decreased risk of RHC with an adjusted HR of 0.58 (95% CI, 0.36-0.95; P=0.031). Conclusions Recipients with a high anti-inflammatory and immune-regulatory genetic profile (high interleukin-10) were protected from RHC. Conversely, recipients with a pro-apoptotic genetic profile (high Fas) or high angiotensin-1-converting enzyme producing genotype were at increased risk of RHC. This represents progress toward understanding the genetic risk factors of posttransplantation outcomes in pediatric heart recipients.

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.

OBJECTIVE: The objective of this study was to determine the association between the genetic polymorphisms of proinflammatory and regulatory cytokines and long-term rates of repeat and late acute rejection episodes in pediatric heart transplant (PHTx) recipients. METHODS: Three hundred twenty-three PHTx recipients: 205 White non-Hispanic, 43 Black non-Hispanic, and 75 Hispanic were analyzed for time to first repeat and late acute rejection episodes by race, age at transplantation, and gene polymorphism (interleukin [IL]-6, -174 G/C, IL-10, -1082 G/A, -819 C/T, 592 C/A; vascular endothelial growth factor (VEGF) -2578 C/A, -460 C/T, +405 C/G; tumor necrosis factor alpha (TNF-alpha)-308 G/A). RESULTS: Recipient black race and older age at transplant were risk factors for both repeat and late rejections, though black race was more significantly related to late rejection (P=0.006). Individually, TNF-alpha high, IL-6 high, VEGF high, and IL-10 low phenotypes did not impact the risk of repeat or late rejection. However, the combination VEGF high/IL-6 high and IL-10 low was associated with increased estimated risk of late rejection (P=0.0004) and only marginally with repeat rejection (P=0.051). In a multivariate analysis, adjusting for age and race, VEGF high/IL-6 high and IL-10 low still remained an independent risk factor for late acute rejection (RR=1.91, P

Inosine 5'-monophosphate dehydrogenase 2 is required for purine synthesis in activated lymphocytes. Variants in the IMPDH2 gene may account for the large inter-individual variability in baseline enzyme activity, immunosuppressive efficacy and side effects in transplant recipients receiving mycophenolic acid. Therefore, the objective of this study was to identify and functionally characterize IMPDH2 variants.DNA samples from 152 solid organ transplant patients were screened at exons and exon/intron junctions of the IMPDH2 genes by PCR amplification followed by bidirectional direct DNA sequencing. Genetic variant was constructed by site-directed mutagenesis and transformed to an inosine 5'-monophosphate dehydrogenase-deficient strain of Escherichia coli h712. Proteins were purified to homogeneity and the enzymatic activity was measured by reduced nicotinamide adenine dinucleotide production.Nine genetic variants were identified in the IMPDH2 gene, with frequencies of the rarer alleles ranging from 0.5 to 10.2%. A novel nonsynonymous variant L263F was identified, and the kinetic assay demonstrated that the inosine 5'-monophosphate dehydrogenase activity of L263F variant was decreased to 10% of the wild-type. The Ki for mycophenolic acid inhibition of the L263F variant was comparable with the wild-type, and the variant Km for inosine 5'-monophosphate and nicotinamide adenine dinucleotide did not change significantly.IMPDH2 has low genetic diversity, but the nonsynonymous variant L263F has a significant impact on inosine 5'-monophosphate dehydrogenase activity. This novel functional variant may be one of the factors contributing to the inter-individual difference of baseline inosine 5'-monophosphate dehydrogenase activity as well as drug efficacy and adverse events in transplant patients.

OBJECTIVES Earlier studies have indicated that the pharmacokinetics of mycophenolic acid (MPA) is influenced by polymorphisms of ABCC2, which encodes for the membrane transporter MRP2. The ABCC2 rs717620 A allele has been associated with enterohepatic recirculation of MPA, and our previous work had correlated the discontinuance of MPA with this allele in pediatric heart transplant patients. Therefore, we hypothesized that the ABCC2 rs717620 A allele would be associated with poorer outcomes including rejection with hemodynamic compromise (RHC), graft failure, and death in the pediatric heart transplant (PHTx) population receiving MPA. METHODS PHTx recipients from 6 institutions in the Pediatric Heart Transplantation Study (PHTS) from the period of 1993–2009, receiving MPA therapy, were genotyped for ABCC2 rs717620. Genotyping was accomplished by direct sequencing. Demographic and outcome data were limited to the data routinely collected as part of the PHTS and included RHC and mortality. RESULTS Two hundred ninety patients were identified who received MPA at some point post transplantation, of which 200 carried the GG genotype, 81 carried the AG genotype, and 9 carried the AA genotype. Follow-up time after transplantation was 6 years. RHC occurred in 76 patients and 18 patients died. In the 281 patients followed up more than 1 year, late RHC (>1 year post transplantation) occurred in 42 patients. While both RHC and late RHC were associated with the ABCC2 rs717620 GG genotype (hazard ratios: 1.80 and 4.57, respectively, p CONCLUSIONS ABCC2 rs717620 polymorphisms varied within racial groups. As a candidate gene assessment, the ABCC2 rs717620 AG and AA genotypes may be associated with improved, rather than poorer, RHC in PHTx patients receiving MPA therapy. ABCC2 rs717620 polymorphisms should be included in any expanded pharmacogenomic analysis of outcomes after pediatric heart transplantation.

Background Single-nucleotide polymorphisms (SNPs) associated with active cytomegalovirus (CMV) infections after lung transplantation have not been identified. Methods SNPs associated with varying levels of interferon (IFN)-γ (+874T/A), tumor necrosis factor-α (−308G/A), interleukin-10 (−1082G/A, −819C/T, −592C/A) and interleukin-6 (−174G/C) were characterized for 170 Caucasian lung transplant recipients who received alemtuzumab induction and valganciclovir prophylaxis against CMV. Results Patients were followed for a median of 34 months post-transplant, and 66% (113 of 170), 24% (40 of 170) and 10% (17 of 170) had no CMV infection, CMV viremia and CMV disease, respectively. Median times to CMV viremia and disease were 7 and 10 months, respectively. For each gene, there was no significant deviation from Hardy–Weinberg equilibrium. Independent risk factors for the development of CMV disease were IFN-γ +874 T/T genotype (associated with high levels of IFN-γ production), CMV donor-positive/recipient-negative (D + /R − ) serostatus and acute cellular rejection requiring augmented immunosuppression ( p = 0.001, 0.003 and 0.049, respectively). The association between IFN-γ +874 T/T genotype and CMV disease was most striking among R + patients ( p = 0.02). D + /R − serostatus was also a significant risk factor for CMV viremia ( p = 0.0005). IFN-γ +874 T/T genotype was associated with significantly lower peak CMV viral loads ( p = 0.03). There were no associations between tumor necrosis factor-α, interleukin-10 or interleukin-6 SNPs and CMV infections. Conclusion A genetic predisposition to elevated IFN-γ levels may play a dual role in controlling active CMV infection among lung transplant recipients receiving alemtuzumab induction and valganciclovir prophylaxis, limiting the extent of viral replication in serum but increasing the risk of CMV disease.

Late infections are common causes of morbidity and mortality after pediatric heart transplantation. In this multicenter study from 6 centers, we investigated the association between genetic polymorphisms (GPs) in immune response genes and late post-transplantation infections in 524 patients.Late infection was defined as a clinical infectious process occurring60 days after transplantation and requiring hospitalization, intravenous antimicrobial therapy, or a life-threatening infection requiring oral therapy. All patients provided a blood sample for GP analyses of 18 GPs in cytokine, growth factor, and effector molecule genes by single specific primer-polymerase chain reaction and/or sequencing. Significant associations in univariable analyses were tested in multivariable Cox regression models.Late infection was common, with 48.7% of patients experiencing ≥ 1 late infection, 25.2% had ≥ 1 late bacterial infection, and 30.5% had ≥ 1 late viral infection. Older age at transplantation was a protective factor for late infection, both bacterial and viral (hazard ratio [HR] 0.89-0.92 per 1-year age increase, p0.001). Adjusting for age, race, and transplant etiology, late bacterial infection was associated with HMOX1 A+326G AG and GG genotypes (HR, 2.41, 95% confidence interval [CI] 1.35-4.30; p = 0.003) and GZMB A-295G AA genotype (HR, 1.47; 95% CI; 1.03-2.1; p = 0.036). Late viral infection was associated with FAS A-670G GG genotype (HR, 1.42; 95% CI, 1.00-2.00; p = 0.050) in the adjusted model and with CTLA4 A+49G AA and AG genotypes (HR, 1.49; 95% CI, 1.02-2.19; p = 0.041) in univariable analysis.We found an association between late bacterial infection and GP of HMOX1, which may control macrophage activation. A weaker association was also found between late viral infection and GP of CTLA4, a regulator of T-cell activation. This represents progress toward understanding the clinical and genetic risk factors of outcomes after transplantation.

Background Mycophenolate mofetil (MMF) is an effective and commonly used immunosuppressant but has frequent adverse events. Genetic polymorphisms may contribute to variability in MMF efficacy and related complications. In this study we explore the distribution frequencies of common single nucleotide polymorphisms (SNPs) of IMPDH1, IMPDH2 and ABCC2 and investigate whether these SNPs influence MMF adverse events in 59 pediatric heart recipients. Methods Genotypes were assessed by TaqMan analysis of: ABCC2 rs717620; IMPDH2 rs11706052; and IMPDH1 rs2288553, rs2288549, rs2278293, rs2278294 and rs2228075. Gastrointestinal (GI) intolerance was defined as diarrhea, vomiting, nausea or abdominal pain requiring dose-holding for >48 hours or MMF discontinuation. Bone marrow toxicity was evaluated using Common Terminology Criteria for Adverse Events Version 3 (CTCAE). Results GI intolerance occurred in 21 patients, and 21 had bone marrow toxicity. The ABCC2 rs717620 A variant was significantly associated with GI intolerance leading to drug discontinuation ( p IMPDH1 rs2278294 A variant and rs2228075 A variant were also associated with greater GI intolerance ( p = 0.029 and p = 0.002, respectively). The IMPDH2 rs11706052 G variant was associated with more frequent neutropenia requiring dose-holding ( p = 0.046). Conclusions In this small sample of pediatric heart transplant patients receiving MMF, ABCC2 , IMPDH1 and IMPDH2 SNPs were associated with MMF GI intolerance and bone marrow toxicity. Thus, genetic polymorphisms may directly influence MMF adverse events.

Background. Granzyme B has been associated with allograft rejection in solid organ transplantation. Single nucleotide polymorphisms (SNPs) in the granzyme B gene might impact its expression. The aims of this study were (1) to establish the frequency of two granzyme B SNPs (A-295G; Q-55R) in pediatric heart transplant (PHTx) recipients and (2) to determine their phenotypic expression in healthy individuals. Methods. Three hundred ninety-six PHTx patients (245 white non-Hispanic, 49 black non-Hispanic, 82 Hispanics, and 20 others) and 52 healthy controls were screened for Q-55R and A-295G. For the control samples, we assessed the frequency of granzyme B positive cells by ELISPOT assay after mitogen stimulation. Results. Among the PHTx recipients, 57% percent of the population carried the Q/Q genotype, whereas 6% were R/R homozygotes. Seven of 49 (14%) black non-Hispanics were R/R homozygotes, whereas 13 of 245 (5%) of white non-Hispanics and 5 of 82 (6%) Hispanics carried the R/R genotype (P=0.02). The A allele frequency of granzyme B A-295G (49.6%) was similar to that of the G allele (50.4%). However, 80% of Black non-Hispanics were A allele carriers compared with 68% of White non-Hispanics (P

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.

Inosine 5'-monophosphate dehydrogenase 1 (IMPDH1) catalyzes the rate-limiting step of the de novo pathway for purine synthesis and is a major target of the immunosuppressive drug mycophenolic acid (MPA). Few variants of the IMPDH1 gene have been reported. The objective of this study was to identify and characterize IMPDH1 variants to determine whether genetic variation contributes to differences in MPA response and toxicity in transplant patients. Seventeen genetic variants were identified in the IMPDH1 gene with allele frequencies ranging from 0.2 to 42.7%. In this study, 191 kidney transplant patients who received mycophenolate mofetil were genotyped for IMPDH1. Two single-nucleotide polymorphisms, rs2278293 and rs2278294, were significantly associated with the incidence of biopsy-proven acute rejection in the first year post-transplantation. Future studies of the multifactorial nature of acute rejection must consider IMPDH1 polymorphisms in MPA-treated patients.

Aim Immune thrombocytopenia (ITP) is defined by persistent low platelet count less than 105/mm3 in the absence of other causes. The pathogeny includes anti-platelet antibodies. Platelet transfusion is rare in ITP, however may be helpful to treat life-threatening hemorrhages. Methods Platelet and HLA-specific antibodies were detected by ELISA. Anti- HLA class I antibodies were identified by Luminex single antigen beads. HLA typing for patient and spouse were done by rSSO. Results 72 year old female was admitted in the emergency room with confusion, extensive petechiae, purpura, echymosses, intracranial and pulmonary hemorrhages and severe thrombocytopenia (2000/mm3). Eight units of platelets were transfused, however the platelet count remained the same. Refractoriness to transfusion was assessed. Patient exhibited both platelet-specific (1a, 1b, 3a, 3b, 4a, 5a, 5b) and anti-HLA antibodies (PRA 80%), explained by only 2 specificities – HLA -A3 and w4 epitope (Fig. 1a). The HLA typing revealed HLA-A3 and B57(w4) as mismatched antigens in husband (patient had 3 pregnancies), while patient HLA was w6. The IgG subtype analysis demonstrated IgG1, which is a strong complement binder and it explained the massive and rapid platelets destruction after receiving the transfusion (Fig. 1b). Download : Download full-size image Conclusions The lack of post-transfusion platelet increment was caused by anti-HLA and platelet specific antibodies, as a result of pregnancy sensitization. In this dramatic case, diagnosis through alloantibody identification and HLA typing supported adequate therapy, with Rituximab and splenectomy, and patient survived a life threatening condition.

TGF1 staining was observed in myocardium. TGF1 expression was significantly correlated with left ventricular ejection fraction (LVEF), but inversely correlated with the left ventricular end-diastolic dimension (LVEDD) and growing ages. Conclusions: Increased TGF1 expression in both myocardium and coronary arterial wall is the hallmark of CAV, that may play an important pathogenesis role in the neointima formation, but may be benefitial in the improvement of cardiac function in heart failure with these two different causes.