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

LE MONSTRE

The entry into language, primary repression, supposes the introduction of the living person into the symbolic order, enabling the genesis of the subject, representability. This movement also throws up a remainder, an unrepresentable, conceptualized by Freud and reformulated by Lacan in his concept of The Real. As structural, this remainder has a necessary presence in the speaker. We place in clinical and artistic presentations the emergence of this rest and the possible treatment of this emergency.La entrada al lenguaje, la represión primaria, supone la introducción del viviente en el orden simbólico, posibilitando la génesis del sujeto y la representabilidad. Este movimiento arroja también un resto, un irrepresentable, conceptualizado por Freud y reformulado por Lacan en su concepto de Lo Real. En tanto estructural, este resto tiene presencia necesaria en el “hablanteser”. Situamos en presentaciones clínicas y artísticas la irrupción de este resto y el tratamiento posible de esta emergencia.L'entrée dans le langage, refoulement primaire, suppose l'introduction du vivant dans l'ordre symbolique, permettant la genèse du sujet, la représentabilité. Ce mouvement rejette aussi un reste, un irreprésentable, conceptualisé par Freud et reformulé par Lacan dans son concept du Réel. Comme structurel, ce reste a une présence nécessaire chez le locuteur. Nous plaçons dans des présentations cliniques et artistiques l'émergence de ce repos et le traitement possible de cette urgence

Effects of polyphenol supplementation to in vitro antioxidant potential of citrus juices

Food preparations containing substances with antioxidant activity have considerably aroused the interest of consumers, which has led to the marketing of a number of dietary supplements such as resveratrol, hesperidin or chlorogenic acid. On the other hand, natural antioxidants present in citrus fruit juices, together with dietary supplements, could contribute to an enhancement of their antioxidant properties and, in turn, alter their physiological impacts. The aim of the study was to evaluate the effect of supplementation of freshly squeezed citrus juices with resveratrol, hesperidin and chlorogenic acid on the in vitro antioxidant potential of the juices. The solutions of juices, selected polyphenols and the mixtures of solutions of juices and solution of polyphenols were analyzed to determine total polyphenol concentration using the Fast Blue method and total antioxidant potential by the ABTS method. As a result three different types of interactions were established: synergistic of chlorogenic acid which additionally increased the antioxidant potential by 35 - 38% over theoretical predictions, additive - after addition of resveratrol, and antagonistic - in the case of hesperidin. While the antioxidant potential was substantially higher in the mixture of mandarin juice with chlorogenic acid, the measured total polyphenol concentration decreased. Also a considerable decrease in the concentration of polyphenols was measured in the mixtures of mandarin and orange juices with resveratrol, all these possibly due to the sensitivity to other substances present in juices of the analytical method applied. A correlation between antioxidant potential of all examined solutions and total polyphenol concentration was found (r2 = 0.8879)

Adipose-Derived Stem Cells undergo differentiation after co-culture with porcine Limbal Epithelial Stem Cells

Mesenchymal stem cells (MSCs) are objects of interest in regenerative medicine. They are used for various therapies such as for the regeneration of bone, chondrocytes and other tissues. Adipose derived stem cells (ADSCs) inter alia are particularly easy to access, they are relatively abundant in fat tissue. ADSCs could be differentiated into many types of cells. To date, it has been proven that ADSCs only differentiate into mesodermal cell lineages. In this study, we present the differentiation of ADSCs into the corneal epithelium. Human ADSCs were placed in a co-culture with porcine limbal epithelial stem cells (LESCs). After 14 days of cultivation, total RNA was extracted for the analysis of the molecular markers (expression of genes of interest). The gene expression was assessed by real-time RT-qPCR. The expression of the surface molecular markers of ADSCs is modulated after co-culturing. We have observed the decrease in CD73, CD90 and CD105 mRNA expression, while the expression of mRNA coding for CK3 and CK12 mRNA was increased in ADSCs co-cultured with porcine limbal epithelial stem cells as compared to the control. We conclude that the coculture of LESCs and ADSCs changed ADSCs’ molecular markers gene expression indicating initiation of differentiation towards limbal cells

Effects of intravitreal ranibizumab on the untreated eye and systemic gene expression profile in age-related macular degeneration

The purpose of this study was to evaluate the systemic effects of intravitreal ranibizumab (Lucentis) treatment in patients with neovascular age-related macular degeneration (AMD). The impact of intravitreal ranibizumab injections on central retinal thickness (CRT) of treated and contralateral untreated eyes, and differences in gene expression patterns in the peripheral blood mononuclear cells were analyzed. The study included 29 patients aged 50 years old and over with diagnosed neovascular AMD. The treatment was defined as 0.5 mg of ranibizumab injected intravitreally in the form of one injection every month during the period of 3 months. CRT was measured by optical coherence tomography. The gene expression profile was assigned using oligonucleotide microarrays of Affymetrix HG-U133A. Studies have shown that there was a change of CRT between treated and untreated eyes, and there were differences in CRT at baseline and after 1, 2, and 3 months of ranibizumab treatment. Three months after intravitreal injection, mean CRT was reduced in the treated eyes from 331.97±123.62 to 254.31±58.75 μm, while mean CRT in the untreated fellow eyes reduced from 251.07±40.29 to 235.45±36.21 μm at the same time. Furthermore, the research has shown that among all transcripts, 3,097 expresses change after the ranibizumab treatment in relation to controls. Among these transcripts, 1,339 were up-regulated, whereas 1,758 were down-regulated. Our results show the potential systemic effects of anti-VEGF therapy for AMD. Moreover, our study indicated different gene expression in peripheral blood mononuclear cells before and after intravitreal ranibizumab treatment

Interleukin 2 as a potential cancer marker in patients after kidney transplantation

Introduction Transplant recipients have a significantly greater incidence of cancer, compared with the general population, who are referred to immunosuppressive therapy as an additional malignancy risk factor. Therefore, there is a need to search for an easy in clinical practice neoplasm predictor, especially for this group of patients. Material and Methods A group of 74 (43M and 31F; aged 46.8 ± 12 years) kidney transplant recipients was investigated in a three-year follow-up study. During the time of observation, 7 patients were diagnosed with neoplasm (7.4 ± 1.5 years after transplantation). A serum level of IL2 (ELISA test) and mRNA level of IL1beta, IL10 and TNFalfa in peripheral mononuclear blood cells – PBMCs (QRT – PCR method) were measured in every year of observation. Analysis of variances and t-Student test were used in groups mean comparison: N – patients developing malignant neoplasm group (24 probes); M – set of probes from patients with malignancies at the moment of diagnosis (11 probes); P – set of probes from patients before developing malignant neoplasm (10 probes); C – control group of healthy transplant recipients (31 probes). Results Among the analyzed agents, only serum IL2 level differed between the analyzed groups, with higher values in the M compared with the P group (p<0.05) and with C group (p<0.01). There were no differences neither between N and C or P and C groups (p = 0.98), nor any correlation between IL2 and IL1b, IL2 and TNFalfa. Conclusions The results may indicate that IL2 serum level might be consider as a useful late unspecific cancer marker, although larger studies should yield verification of this finding