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Marion Nagy

Publications and source records attributed to Marion Nagy.

6 recordsLinked to original sources
PubMed2006

Evaluation of whole-genome amplification of low-copy-number DNA in chimerism analysis after allogeneic stem cell transplantation using STR marker typing.

Whole-genome DNA amplification (WGA) is a promising method that generates large amounts of DNA from samples of limited quantity. We investigated the accuracy of a multiplex PCR approach to WGA over STR loci. The amplification bias within a locus and over all analyzed loci was investigated in relation to the amount of template in the WGA reaction, the specific STR locus, and allele length. We observed reproducible error-free STR profiles with 10 ng down to 1 ng of DNA template. The amplification deviation at a locus and between loci was within the intra-method reproducibility. WGA is the method of choice for amplifying nanogram amounts of genomic DNA for different applications. We detected unbalanced STR amplifications at one locus and between loci, allelic drop-outs, and additional alleles after WGA of low-copy-number DNA. We found that the high number of drop-outs and drop-ins could be eradicated using pooled DNA from separate WGA reactions even with as little as 100 pg of starting template. Nevertheless, the quality of the results was still not sufficient for use in routine chimerism analysis of limited specific cell populations after allogeneic stem cell transplantation.

Chimerism↗
PubMed2005

Sarcoidosis is associated with a truncating splice site mutation in BTNL2.

Sarcoidosis is a polygenic immune disorder with predominant manifestation in the lung. Genome-wide linkage analysis previously indicated that the extended major histocompatibility locus on chromosome 6p was linked to susceptibility to sarcoidosis. Here, we carried out a systematic three-stage SNP scan of 16.4 Mb on chromosome 6p21 in as many as 947 independent cases of familial and sporadic sarcoidosis and found that a 15-kb segment of the gene butyrophilin-like 2 (BTNL2) was associated with the disease. The primary disease-associated variant (rs2076530; P(TDT) = 3 x 10(-6), P(case-control) = 1.1 x 10(-8); replication P(TDT) = 0.0018, P(case-control) = 1.8 x 10(-6)) represents a risk factor that is independent of variation in HLA-DRB1. BTNL2 is a member of the immunoglobulin superfamily and has been implicated as a costimulatory molecule involved in T-cell activation on the basis of its homology to B7-1. The G --> A transition constituting rs2076530 leads to the use of a cryptic splice site located 4 bp upstream of the affected wild-type donor site. Transcripts of the risk-associated allele have a premature stop in the spliced mRNA. The resulting protein lacks the C-terminal IgC domain and transmembrane helix, thereby disrupting the membrane localization of the protein, as shown in experiments using green fluorescent protein and V5 fusion proteins.

Bronchoalveolar Lavage↗
PubMed2004

Nonmyeloablative stem cell transplantation in patients with ALL and AML results in low nonrelapse mortality despite high rate of infections and GVHD.

28 patients with high-risk acute lymphoblastic (ALL) or acute myelogenous leukemia (AML) underwent nonmyeloablative stem cell transplantation (NST) from HLA-identical donors because of one or several contraindications against myeloablative conditioning. Out of 28 patients, nine (32%) had pulmonary or hepatosplenic infiltrates due to invasive fungal infections (IFI) before NST. Out of a total of 28 patients, 17 (61%) had uncontrolled leukemia before NST. Conditioning was performed with fludarabine 180 mg/m(2), busulfan 8 mg/kg and antithymocyte globulin 40 mg/kg. After NST, fever of unknown origin, sepsis or pneumonia developed in 18/28 patients (64%) overall. IFI reactivated in 3/9 patients after NST. Out of, 28 patients, 13 (46%) had late onset of acute graft-versus-host disease (GvHD), which developed at a median of 83 days after NST. GvHD frequently developed after donor lymphocyte infusions. After a median follow-up of 8 months (2-46 months), 14/28 patients (50%) have died from relapse and 1/28 patients (4%) has died from sepsis. Among 28 patients, 13 (46%) are alive in complete remission (CR). Six of 17 patients (35%) with uncontrolled disease and 7/11 patients (63%) with CR before NST are alive in CR. Probability of overall survival at 2 years is 38%. In summary, NST offers a therapeutic alternative to patients with high-risk ALL or AML, who have contraindications against conventional high-dose conditioning. Low NRM was encountered despite high morbidity, but relapse rate was high. Therefore, controlled studies are necessary to elucidate the place of NST in the therapy of high-risk acute leukemias.

Acute Disease↗
PubMed2001

Investigation of HLA-DPA1 genotypes as predictors of inflammatory bowel disease in the German, South African, and South Korean populations.

BACKGROUND AND AIMS: Inflammatory bowel disease (IBD) is a polygenic disorder, as demonstrated by epidemiological evidence, genetic linkage, and the identification of the first susceptibility gene, NOD2. Genetic linkage analysis has identified and replicated several genomic regions as locations for susceptibility genes, including chromosome 6p (termed IBD3). The HLA-DP genes play an important role in antigen presentation and are located within the chromosome 6p linkage region. PATIENTS AND METHODS: We investigated HLA-DPA1 as a positional and functional candidate gene for IBD using 249 German multiplex IBD families, 174 unrelated German controls, 48 monoplex families from a mixed South African population, 87 IBD patients, and 71 controls from a South Korean sample. Polymorphisms in exon 2 at amino acid positions 31, 37-38 and 50 were genotyped using direct sequencing. Analyses were performed using chi(2) statistics, multipoint transmission disequilibrium test and nonparametric linkage analysis. RESULTS: A marginally significant association for Crohn's disease was detected in the German family cohort for DPA1*02021. This finding was not replicated in ulcerative colitis or any of the other populations. CONCLUSION: HLA-DPA1 is not a major determinant of IBD risk in any of the three populations. The transmission distortion observed in the German cohort may indicate an extended haplotype, suggesting another disease relevant gene in the vicinity of HLA-DPA.

Case-Control Studies↗
PubMedDate not supplied

Investigation of the HLA-DRB1 locus in alopecia areata.

To further evaluate the nature of the HLA association with alopecia areata (AA), we investigated the HLA-DRB1 locus in 161 AA patients and 165 matched controls from Belgium and Germany. HLA-DRB1 typing was performed using a recently established method that employs a combination of PCR-SSP (sequence specific priming) and Pyrosequencing(TM) technology. No significant differences were observed for HLA allele groups DRB1 *01, *07, *08, *09, *10, *11, *13, *14, *15, and *16. HLA-DRB1*03 was found to confer a protective effect (7.5% versus 13.6%, p = 0.011). Additional genotyping at the allelic level revealed a significant difference in HLA-DRB1*0301 between patients and controls (6.8% versus 11.2%, p = 0.048). The DRB1*04 allele group was confirmed as a risk factor for the development of AA (20.8% versus 13.3%, p = 0.012), with the allele DRB1*0401 accounting for the greatest proportion of the effect (13.4% versus 7.3%, p = 0.014). Results obtained after subgrouping of the patients according to age at onset, severity and family history of the disease suggests that the genetic effects of the HLA system are strongest in familial cases of the disease.

Adolescent↗