Gene expression profiling of brains from bovine spongiform encephalopathy (BSE)-infected cynomolgus macaques
BMC GENOMICS
Authors: Barbisin, Maura; Vanni, Silvia; Schmaedicke, Ann-Christin; Montag, Judith; Motzkus, Dirk; Opitz, Lennart; Salinas-Riester, Gabriela; Legname, Giuseppe
Abstract
Background: Prion diseases are fatal neurodegenerative disorders whose pathogenesis mechanisms are not fully understood. In this context, the analysis of gene expression alterations occurring in prion-infected animals represents a powerful tool that may contribute to unravel the molecular basis of prion diseases and therefore discover novel potential targets for diagnosis and therapeutics. Here we present the first large-scale transcriptional profiling of brains from BSE-infected cynomolgus macaques, which are an excellent model for human prion disorders. Results: The study was conducted using the GeneChip (R) Rhesus Macaque Genome Array and revealed 300 transcripts with expression changes greater than twofold. Among these, the bioinformatics analysis identified 86 genes with known functions, most of which are involved in cellular development, cell death and survival, lipid homeostasis, and acute phase response signaling. RT-qPCR was performed on selected gene transcripts in order to validate the differential expression in infected animals versus controls. The results obtained with the microarray technology were confirmed and a gene signature was identified. In brief, HBB and HBA2 were down-regulated in infected macaques, whereas TTR, APOC1 and SERPINA3 were up-regulated. Conclusions: Some genes involved in oxygen or lipid transport and in innate immunity were found to be dysregulated in prion infected macaques. These genes are known to be involved in other neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Our results may facilitate the identification of potential disease biomarkers for many neurodegenerative diseases.
A Simple Whole-Blood Polymerase Chain Reaction without DNA Extraction for Thalassemia Diagnosis
HEMOGLOBIN
Authors: Srisuwan, Wibhasiri; Tatu, Thanusak
Abstract
Polymerase chain reaction (PCR) diagnosis of thalassemia usually relies on using genomic DNA. Preparing the genomic DNA can lead to sample-to-sample contamination. This report was aimed to establish the PCR protocol using whole-blood for detecting mutations of - and -globin genes causing the thalassemia syndrome. First, the PCR facilitators, betaine and bovine serum albumin (BSA), were tested, simultaneously with an adjustment of PCR thermal cycler and of whole-blood volume. Thereafter, the established whole-blood PCR was applied for detecting, in both known and unknown samples, the HBA1 Southeast Asian (--(SEA)) (NG_000006.1: g.26264_45564del19301) deletion, Hb Constant Spring (Hb CS, HBA2: c.427T>C, (CS)), codon 17 (A>T) (HBB: c.52A>T), codons 41/42 (-TTCT) (HBB: c.126_129delCTTT) deletion, -28 (A>G) (HBB: c.-78A>G) and codon 26 (G>A) (Hb E or HBB: c.79G>A). It was shown that the whole-blood PCR worked successfully in 9.0% (w/v) betaine, with 1L of EDTA whole blood and with addition of 10 heat-cool steps (3min. at 94 degrees C, followed by 3min. at 55 degrees C) prior to the typical thermal cycles for the mutations. The capability of the new whole-blood PCR was similar to that of the typical DNA-based PCR. Therefore, the newly established whole-blood PCR could be performed for PCR diagnosis of thalassemia. Using this platform, sample-to-sample contamination should be eliminated.