Partial nephrectomy for renal cell carcinoma in an allograft kidney with limited functional reserve

Abstract The increased risk of malignancies is a well-recognized complication of organ transplantation. When renal cell carcinoma (RCC) occurs in kidney transplant recipients, less than 10% of it affects the allograft. Recent experience suggests that partial allograft nephrectomy for tumours less than 4 cm may be considered the treatment of choice. We report a case of a 3.3 cm RCC discovered in a renal allograft. Limited allograft function was due to segmental infarction after transplant surgery and chronic allograft nephropathy. She underwent successful partial allograft nephrectomy. At 36 months post-surgery, there is no evidence of RCC recurrence and she remains free of renal replacement therapy

2′-O Methylation of Internal Adenosine by Flavivirus NS5 Methyltransferase

RNA modification plays an important role in modulating host-pathogen interaction. Flavivirus NS5 protein encodes N-7 and 2′-O methyltransferase activities that are required for the formation of 5′ type I cap (m7GpppAm) of viral RNA genome. Here we reported, for the first time, that flavivirus NS5 has a novel internal RNA methylation activity. Recombinant NS5 proteins of West Nile virus and Dengue virus (serotype 4; DENV-4) specifically methylates polyA, but not polyG, polyC, or polyU, indicating that the methylation occurs at adenosine residue. RNAs with internal adenosines substituted with 2′-O-methyladenosines are not active substrates for internal methylation, whereas RNAs with adenosines substituted with N6-methyladenosines can be efficiently methylated, suggesting that the internal methylation occurs at the 2′-OH position of adenosine. Mass spectroscopic analysis further demonstrated that the internal methylation product is 2′-O-methyladenosine. Importantly, genomic RNA purified from DENV virion contains 2′-O-methyladenosine. The 2′-O methylation of internal adenosine does not require specific RNA sequence since recombinant methyltransferase of DENV-4 can efficiently methylate RNAs spanning different regions of viral genome, host ribosomal RNAs, and polyA. Structure-based mutagenesis results indicate that K61-D146-K181-E217 tetrad of DENV-4 methyltransferase forms the active site of internal methylation activity; in addition, distinct residues within the methyl donor (S-adenosyl-L-methionine) pocket, GTP pocket, and RNA-binding site are critical for the internal methylation activity. Functional analysis using flavivirus replicon and genome-length RNAs showed that internal methylation attenuated viral RNA translation and replication. Polymerase assay revealed that internal 2′-O-methyladenosine reduces the efficiency of RNA elongation. Collectively, our results demonstrate that flavivirus NS5 performs 2′-O methylation of internal adenosine of viral RNA in vivo and host ribosomal RNAs in vitro

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Late-onset and atypical presentation of Pneumocystis carinii pneumonia in a renal transplant recipient

The original publication can be found at www.springerlink.comPneumocystis jivorecii (formerly known as carinii) pneumonia (PCP) is potentially a life-threatening opportunistic infection after organ transplantation, occurring most frequently in the first 12 months, where the incidence rate is several-fold higher than in later years. PCP typically presents with fever, cough, dyspnoea and hypoxia. In organ transplant recipients, the onset of symptoms is generally more fulminant compared to patients infected with the human immunodeficiency virus. We present a patient who developed PCP five years after a renal transplantation. His presentation was characterised by atypical symptoms and an indolent onset. Previous acute vascular rejection, ongoing maintenance prednisolone usage, cytomegalovirus seropositivity and past tuberculous infection may have predisposed this patient to PCP.Jordan Y. Z. Li, Tuck Y. Yong, David I. Grove and P. Toby H. Coate

The selection of acute medical admissions for a short-stay unit

Objective of this study is to evaluate the selection of patients to be admitted to a hospital medical short-stay unit (SSU) where acute medical admissions with a predicted length of stay of between 24 and 72 h are managed. This is a retrospective observational study evaluating outcomes of all admissions to the medical SSU between January 2005 and December 2008. Factors that influence inappropriate allocation of patients to the SSU or alternative longer stay medical units were evaluated. Length of stay (LOS), mortality, Charlson score, admission to intensive care unit (ICU) (from the SSU), discharge diagnosis, and 7-day readmission rate were analysed. Over 4 years, 45% of the general medical inpatient take, 9,125 admission episodes, were managed by the medical SSU. On an average, 72% of these admissions to the SSU stayed fewer than 72 h. After excluding in-hospital deaths, there were 8,381 admissions to the general medical unit discharged within 72 h, and 77% of these were managed by the SSU during the study period. Inappropriate admissions to the SSU (LOS more than 72 h) tended to be older patients with more complex medical comorbidities. Other factors contributing to prolonged stay in the SSU included weekend admissions, and transfers to the ICU. The 7-day readmission rate was low at 3%; the all-cause hospital mortality for patients admitted to the medical SSU was 2% despite a 32% increase in workload in the medical SSU over these 4 years. In the context of fixed resources and a steeply increasing patient workload, a large proportion of general medical patients can be managed in a medical SSU with the majority being discharged home within 72 h while keeping all-cause in-hospital mortality and readmission rates low. More accurate identification of appropriate patients on admission by using a physiological clinical score and addressing operational issues particularly on weekends could lead to a more efficient SSU.Tuck Y. Yong, Jordan Y. Z. Li, Susan Roberts, Paul Hakendorf, David I. Ben-Tovim and Campbell H. Thompso