Distinct global DNA methylation and NF-κB expression profile of preimplantation biopsies from ideal and non-ideal kidneys.

BACKGROUND: Epigenetic mechanisms may affect the ideal and non-ideal kidneys selected for transplantation and their inflammatory gene expression profile differently and may contribute to poor clinical outcomes. OBJECTIVE: Study the Global DNA methylation and the expression profiles of the DNA methyltransferases (DNMTs) and nuclear factor kappa B (NF-κB) in preimplantation kidney biopsies from ideal and non-ideal kidneys (expanded criteria donor (ECD) and with KDPI > 85%). METHODS: In a sample consisting of 45 consecutive pre-implantation biopsies, global DNA methylation levels were detected by LINE-1 repeated elements using bisulfite pyrosequencing. DNMT gene expression was assessed by real-time quantitative polymerase chain reaction, and NF-κB protein expression by immunofluorescence. RESULTS: ECD kidneys displayed increased methylation levels in LINE-1, and DNMT1 and DNMT3B expression was upregulated when comparing ECD to standard criteria donor kidneys. Similarly, kidneys with KDPI > 85% exhibited increased LINE-1 methylation and DNMT1 upregulation when compared to a KDPI ≤ 85%. NF-κB protein expression levels were greatly increased in both types of non-ideal kidneys compared to ideal kidneys. Moreover, hypermethylation of LINE-1 was associated with cold ischemia time > 20 h and ECD kidney classification. CONCLUSIONS: This study shows that global DNA hypermethylation and high expression of NF-κB occurred in both types of non-ideal kidneys and were associated with prolonged cold ischemia time. Global DNA methylation can be a useful tool to assess non-ideal kidneys and hence, could be used to expand the pool of kidneys donors.

Variables associated to fetal microchimerism in systemic lupus erythematosus patients.

In the present study, we sought to identify the factors during the pregnancy of systemic lupus erythematosus (SLE) patients that could be linked to the presence and proliferation of male fetal cells (MFC) and the possible relation between these factors and development of lupus nephritis (LN). We evaluated 18 healthy women (control group) and 28 women affected by SLE. Genomic DNA was extracted from peripheral blood and quantified using the technique of quantitative real-time polymerase chain reaction (qPCR) for specific Y chromosome sequences. The amount of MFC was significantly higher in the SLE group compared with the controls (SLE 252 ± 654 vs control 2.13 ± 3.7; P = 0.029). A higher amount of MFC was detected among multiparous SLE patients when compared with the control group (SLE 382 ± 924 vs control 0.073 ± 0.045; P = 0.019). LN was associated with reduced amount of MFC (LN 95.5 ± 338 vs control 388 ± 827; P = 0.019) especially when they have delivered their child before age 18 (LN 0.23 ± 0.22 vs control 355 ± 623; P = 0.028). SLE patients present a higher amount of MFC, which may increase with the time since birth of the first male child. LN patients showed an inverse correlation with MFC, suggesting that the role of the cells may be ambiguous during the various stages of development of the disease.