Articles by Valérie Duret in JoVE
High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment Aymric Kisserli1,2, Thierry Tabary1,2, Jacques Henri Max Cohen1,2, Valérie Duret1,2, Rachid Mahmoudi3,4 1Department of Immunology, Reims University Hospitals, Robert Debré Hospital, 2Faculty of Medicine, LRN EA 4682, University of Reims Champagne-Ardenne, 3Department of Internal Medicine and Geriatrics, Reims University Hospitals, Maison Blanche Hospital, 4Faculty of Medicine, EA 3797, University of Reims Champagne-Ardenne Here, we describe an innovative method to determine complement receptor 1 (CR1) length polymorphisms for use in several applications, particularly the assessment of susceptibility to diseases such as Alzheimer's disease (AD). This method could be useful to better understand the role of CR1 isoforms in the pathogenesis of AD.
Other articles by Valérie Duret on PubMed
Analysis of Complement Receptor Type 1 Expression on Red Blood Cells in Negative Phenotypes of the Knops Blood Group System, According to CR1 Gene Allotype Polymorphisms Transfusion. Jul, 2010 | Pubmed ID: 20210926 The KN blood group system, which consists of nine antigen specificities, is located on complement receptor Type 1 (CR1/CD35). CR1, a complement regulatory protein, acts as a vehicle for immune complex clearance. CR1 exhibits a red blood cell (RBC) density polymorphism. CR1 sites on RBCs in normal individuals range from 150 to 1200 molecules per cell. CR1 density polymorphism is regulated by HindIII restriction fragment length polymorphism and Q981H and P1786R polymorphisms in Caucasians. Yet, the role of the different polymorphisms in determining the CR1 density on RBCs remains unknown. The "null" serologic KN phenotype, known as Helgeson phenotype, was reported to be related with a very low CR1 density, less than 150 molecules per cell.
Alzheimer's Disease is Associated with Low Density of the Long CR1 Isoform Neurobiology of Aging. Apr, 2015 | Pubmed ID: 25666996 The long complement receptor type 1 (CR1) isoform, CR1*2 (S), has been identified as being associated with Alzheimer's disease (AD) risk. We aimed to analyze the phenotypic structural and expression aspects (length and density) of CR1 in erythrocytes of 135 Caucasian subjects (100 AD and 35 controls). CR1 length polymorphism was assessed at protein and gene levels using Western blot and high-resolution melting, respectively. CR1 sites on erythrocytes were enumerated by flow cytometry. CR1 gene analysis, spotting the rs6656401 and rs3818361 polymorphisms, was performed by pyrosequencing. The CR1 density was significantly lower in AD patients expressing the CR1*2 isoform compared with the controls (p = 0.001), demonstrating lower expression of CR1 in CR1*2 carriers. Our data suggested the existence of silent CR1 alleles. Finally, rs6656401 and rs3818361 were strongly associated with CR1 length polymorphism (p < 0.0001). These observations indicate that AD susceptibility is associated with the long CR1 isoform (CR1*2), albeit at a lower density, suggesting that AD results from insufficient clearance of plaque deposits rather than increased inflammation.