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In this cross-sectional and longitudinal analysis of mapping the T-cell repertoire in kidney transplant recipients, we have investigated and validated T-cell clonality, immune repertoire chronology at rejection, and contemporaneous allograft biopsy quantitative tissue injury, to better understand the pathobiology of acute T-cell fraction, T-cell repertoire and antibody-mediated kidney transplant rejection. To follow the dynamic evolution of T-cell repertoire changes before and after engraftment and during biopsy-confirmed acute rejection, we sequenced 323 peripheral blood samples from 200 unique kidney transplant recipients, with (n=100) and without (n=100) biopsy-confirmed acute rejection. We report that patients who develop acute allograft rejection, have lower (p=0.01) T-cell fraction even before transplantation, followed by its rise after transplantation and at the time of acute rejection accompanied by high TCR repertoire turnover (p=0.004). Acute rejection episodes occurring after the first 6 months posttransplantation, and those with a component of antibody-mediated rejection, had the highest turnover; p=0.0016) of their T-cell repertoire. In conclusion, we validated that detecting repertoire changes in kidney transplantation correlates with post-transplant rejection episodes suggesting that T-cell receptor sequencing may provide recipient pre-transplant and posttransplant predictors of rejection risk. [ABSTRACT FROM AUTHOR]

ABSTRACT: Variants of spatial interpolation and data‐driven methods to fill gaps in daily precipitation records are developed and evaluated in this study. The evaluated methods include variations of inverse distance and correlation weighting procedures, linear weight optimization and artificial neural networks. An already existing method, support vector logistic regression‐based copula, is also assessed. Optimal weights are estimated using inverse distance and correlation‐based weighting methods, post‐corrections of spatially interpolated estimates for rain or no rain classifications using support vector machine (SVM), and variations of a single best classifier (SBC) are used. The optimal number of gauges for use in spatial interpolation methods and for artificial neural network‐based method are selected. Three benchmark methods provide a basis against which all the methods are compared: single best estimator (SBE), and spatial and climatological mean estimators (SME and CME). All of the methods are tested for estimating varying amounts of missing precipitation data at 53 rain gauges located in South Florida, USA. Results show that the linear weight optimization method with an SBE provides the best estimates of daily precipitation values based on several performance metrics. Results from evaluation of different methods and their variants indicate use of optimized exponents in distance and correlation‐based weighting methods, classifiers for rain or no rain conditions, and an optimal number of neighbours in spatial interpolation improve estimates of missing data. Corrections to missing data estimates using nearest neighbours can help in improving the accuracy of rain and no rain state determinations with a possibility of introducing bias in estimates. [ABSTRACT FROM AUTHOR]

Abstract: The mda-7 gene (approved gene symbol IL24) is a novel tumor suppressor gene with tumor-apoptotic and immune-activating properties. We completed a Phase I dose-escalation clinical trial, in which a nonreplicating adenoviral construct expressing the mda-7 transgene (INGN 241; Ad-mda7) was administered intratumorally to 22 patients with advanced cancer. Excised tumors were evaluated for vector-specific DNA and RNA, transgenic MDA-7 expression, and biological effects. Successful gene transfer as assessed by DNA- and RT-PCR was demonstrated in 100% of patients evaluated. DNA analyses demonstrated a dose-dependent penetration of INGN 241 (up to 4 × 108 copies/μg DNA at the 2 × 1012 vp dose). A parallel distribution of vector DNA, vector RNA, MDA-7 protein expression, and apoptosis induction was observed in all tumors, with signals decreasing with distance away from the injection site. Additional evidence for bioactivity of INGN 241 was illustrated via regulation of the MDA-7 target genes β-catenin, iNOS, and CD31. Transient increases (up to 20-fold) of serum IL-6, IL-10, and TNF-α were observed. Significantly higher elevations of IL-6 and TNF-α were observed in patients who responded clinically to INGN 241. Patients also showed marked increases of CD3+CD8+ T cells posttreatment, suggesting that INGN 241 increased systemic TH1 cytokine production and mobilized CD8+ T cells. Intratumoral delivery of INGN 241 induced apoptosis in a large volume of tumor and elicited tumor-regulatory and immune-activating events that are consistent with the preclinical features of MDA-7/IL-24. [Copyright &y& Elsevier]

Abstract: The melanoma differentiation-associated gene-7 (mda-7; approved gene symbol IL24) is a tumor suppressor gene whose expression induces selective apoptosis in tumor cells. To characterize the safety and biologic activity of mda-7 gene transfer, we conducted a phase I trial using intratumoral injections of an adenovirus containing the mda-7 construct (Ad-mda7; INGN 241; 2 × 1010 to 2 × 1012 vp) in 28 patients with resectable solid tumors. One hundred percent of injected lesions demonstrated INGN 241 vector transduction, transgenic mRNA, elevated MDA-7 protein, and apoptosis induction, with the highest levels near the injection site. Apoptosis of cells in injected tumors was consistently observed even in heavily pretreated patients. INGN 241 vector DNA and mRNA were detected more than 1 cm from the injection site, whereas MDA-7 protein and bioactivity were more widely distributed. Toxicity attributable to the injections was self-limiting and generally mild; however, one patient experienced a grade 3 SAE possibly related to the study drug. Evidence of clinical activity was found in 44% of lesions with the repeat injection schedule, including complete and partial responses in two melanoma patients. Thus intratumoral administration of INGN 241 is well tolerated, induces apoptosis in a large percentage of tumor cells, and demonstrates evidence of clinically significant activity. [Copyright &y& Elsevier]