Characterization of porcine endogenous retrovirus expression in neonatal and adult pig pancreatic islets

BACKGROUND: Pig islets represent an alternative to the current modes of treatment for patients with diabetes. However, the concerns over pathogen transmission including that of PERV limit their immediate, widespread usage in humans. It has been previously demonstrated that PERV copy number and particularly expression levels can vary considerably between individuals and within different tissues of a single animal. In general, expression levels have been found to be particularly low in the pancreas compared to other porcine tissues suggesting a reduced risk associated with the use of this tissue. Data regarding this crucial aspect, however, remain limited and little is known about PERV status of islets themselves, which represent the final product to be transplanted. In addition, comparative analysis of the PERV status of neonatal piglets with adults is important as they are increasingly considered as potential islet donors for xenotransplantation. METHODS: Tissue samples from 51 neonatal piglets (age between 14 and 21 days) and 29 adult pigs were collected from Belgian landrace pigs used for pancreas procurement and islet isolation. Tissue biopsies were used to extract DNA for PERV copy number quantification by qPCR and RNA for PERV expression by qRT-PCR. RESULTS: As expected, PERV expression demonstrated great variation and was significantly lower in pancreas compared to other tissues. More importantly, PERV RNA expression was found to be specifically enriched in pancreatic islets reaching values similar to those found in other tissues such as liver and kidney. Interestingly, this expression was not coupled with the detection of reverse transcriptase in islet cultures or indeed detection of PERV virus. Lung, spleen, and lymph node consistently showed the highest levels of PERV expression. Comparison of PERV in neonatal and adult pigs showed that copy number did not vary significantly from birth to adulthood. PERV expression on the other hand was significantly lower in neonatal pig islets compared to adult islets and did not increase over the period of culture. CONCLUSION: Our study confirms the low level of PERV expression in whole pancreas in a large population of both neonatal and adult pigs (n=80). The level of PERV expression was however higher in the endocrine tissue than in the exocrine cells. There was no correlation between PERV status in donor PBMCs and islet cells, and no evidence of active replication in in vitro regardless of PERV expression in islet cells. Moreover, neonatal pig islets were found to have significantly lower PERV expression compared to adult islets. Neonatal islets have been suggested as the best choice for xenotransplantation in terms of economic and procurement considerations; the PERV status reported here would also potentially support their use

Molecular epidemiology of serogroup a meningitis in Moscow, 1969 to 1997.

Molecular analysis of 103 serogroup A Neisseria meningitidis strains isolated in Moscow from 1969 to 1997 showed that four independent clonal groupings were responsible for successive waves of meningococcal disease. An epidemic from 1969 to the mid-1970s was caused by genocloud 2 of subgroup III, possibly imported from China. Subsequent endemic disease through the early 1990s was caused by subgroup X and then by subgroup VI, which has also caused endemic disease elsewhere in eastern Europe. A 1996 epidemic was part of the pandemic spread from Asia of genocloud 8 of subgroup III. Recent genocloud 8 epidemic disease in Moscow may represent an early warning for spread of these bacteria to other countries in Europe

SYNTAX score II predicts long-term mortality in patients with one- or two-vessel disease

Objective SYNTAX score II (SSII) is a long-term mortality prediction model to guide the decision making of the heart-team between coronary artery bypass grafting or percutaneous coronary intervention (PCI) in patients with left main or three-vessel coronary artery disease. This study aims to investigate the long-term predictive value of SSII for all-cause mortality in patients with one- or two-vessel disease undergoing PCI. Methods A total of 628 patients (76% men, mean age: 61±10 years) undergoing PCI due to stable angina pectoris (43%) or acute coronary syndrome (57%), included between January 2008 and June 2013, were eligible for the current study. SSII was calculated using the original SYNTAX score website (www.syntaxscore.com). Cox regression analysis was used to assess the association between continuous SSII and long-term all-cause mortality. The area under the receiver-operating characteristic curve was used to assess the performance of SSII. Results SSII ranged from 6.6 to 58.2 (median: 20.4, interquartile range: 16.1–26.8). In multivariable analysis, SSII proved to be an independent significant predictor for 4.5-year mortality (hazard ratio per point increase: 1.10; 95% confidence interval: 1.07–1.13; p<0.001). In terms of discrimination, SSII had a concordance index of 0.77. Conclusion In addition to its established value in patients with left main and three-vessel disease, SSII may also predict long-term mortality in PCI-treated patients with one- or two-vessel disease

Characterizing steroid hormone receptor chromatin binding landscapes in male and female breast cancer

Male breast cancer (MBC) is rare and largely hormonally driven. Here, the authors examine the action of steroid hormone receptors in male and female breast cancers and find gender selective hormone receptor action that associates with the survival of MBC patients