The influence of HLA A-B-DR matching on cytomegalovirus disease after renal transplantation. Evidence that HLA-DR7-matched recipients are more susceptible to cytomegalovirus disease.

We examined the prevalence of cytomegalovirus infectious episodes, as defined by clinical, virological, and serological criteria (i.e., CMV disease), in 660 kidney graft recipients; 109 patients (16.5%) developed the disease, and 551 did not. No significant statistical link between CMV disease prevalence and a given HLA-A, -B, or -DR allele was observed. However, patients with HLA-DR7 matched grafts were statistically more frequently found (P < 0.01) in the group of recipients who developed CMV disease as compared with the group who did not develop CMV disease. Furthermore, among patients who developed CMV disease, a significant increase of HLA-DR7 matched over DR7 mismatched patients was noted, whereas no difference between matched and mismatched recipients for the other HLA-DR alleles was found. No difference in the severity of graft failure, often observed during, or immediately after, the CMV episode, was noted between patients matched or mismatched for HLA-DR7. Our data suggest that donor/recipient matching for HLA-DR7 is associated with increased CMV disease.     

Combined use of RFLP and PCR-ASO typing for HLA-DR-Dw and DQw typing.

Due to some limitations of restriction fragment length polymorphism (RFLP) analysis in HLA-DR-DQ typing, we present a combined use of RFLP and polymerase chain reaction (PCR)-allele-specific oligonucleotide (ASO) typing. This scheme consists in selectively amplifying the few RFLP ill-defined genes (DR1/DR'Br' and DR4-Dw subsets) using PCR with allele specific primers to avoid cross-hybridization.     

Nonfibrous mineral particles in bronchoalveolar lavage fluid and lung parenchyma from the general population.

It is recognized that bronchoalveolar lavage (BAL) gives access to particulate matter present at the surface of the peripheral airspace. The objective of the present study was to evaluate the ability of BAL fluid analysis to predict the lung parenchymal particulate content. A BAL fluid sample, the parenchyma sample having undergone BAL, and an adjacent parenchyma sample that had not undergone BAL were obtained at autopsy on 10 individuals without any known recent occupational exposure to mineral particles. The particles (larger than 0.1 micron) were analyzed using a transmission electron microscope equipped with a microanalysis system. Nineteen types of particles were distinguished. The distribution of particle types in the three samples was compared. No significant difference between the relative concentrations was found, except for two particle types: fly ash (excess in BAL fluid compared with lavaged lung) and kaolinite (excess in lavaged lung compared with adjacent area). Such differences may be due to limitations in methodology. Although no correlation could be found between the absolute concentrations of particles in BAL fluid and in lung tissue, analysis of particles in BAL fluid may provide information on the types of particles present in the lung parenchyma.     

Molecular biology diagnosis in oncology

The applications of molecular biology diagnosis in oncology are presented and discussed. These are: improved nosologic definition; diagnosis of clonality; definition of new prognosis subgroups in some cancers; as an aid in bone marrow transplantation follow-up; diagnosis of the residual disease; early diagnosis of cancer; evaluation of individual cancer risk.     

Mutations in the cationic trypsinogen gene and evidence for genetic heterogeneity in hereditary pancreatitis

Hereditary pancreatitis (HP) is a rare inherited disorder, characterised by recurrent episodes of pancreatitis often beginning in early childhood. The mode of inheritance suggests an autosomal dominant trait with incomplete penetrance. The gene, or at least one of the genes, responsible for hereditary pancreatitis has been mapped to the long arm of chromosome 7 and a missense mutation, an arginine to histidine substitution at residue 117 in the trypsinogen cationic gene (try4) has been shown to segregate with the HP phenotype. The aim of this work was to investigate the molecular basis of hereditary pancreatitis. This study was performed on 14 HP families. The five exons of the trypsinogen cationic gene were studied using a specific gene amplification assay combined with denaturing gradient gel electrophoresis (DGGE). The present paper describes three novel mutations, namely K23R and N29I and a deletion -28delTCC in the promoter region. We also found a polymorphism in exon 4, D162D. In eight of these families we found a mutation which segregates with the disease. A segregation analysis using microsatellite markers carried out on the other families suggests genetic heterogeneity in at least one of them. Our findings confirm the implication of the cationic trypsinogen gene in HP and highlight allelic diversity associated with this phenotype. We also show that the pattern of inheritance of HP is probably complex and that other genes may be involved in this genetic disease.     

Human malignant mesothelial cells: Variability of ultrastructural features in established and nude mice transplanted cell lines

The aim of this study was to determine, by transmission electron microscopy, the differentiation features of 21 human malignant mesothelioma cell lines (HMCLs) established from 13 specimens of 12 confirmed human malignant mesotheliomas, and of tumours induced in nude mice injected with 16 HMCLs. Fifty per cent of HMCLs showed typical mesothelial differentiation (long and slender microvilli, desmosomes, perinuclear intermediate filaments); 29 per cent did not show differentiation; and the remainder were poorly differentiated. Three human tumour specimens gave several different HMCLs; the cell lines obtained from a given tumour exhibited variable mesothelial differentiation. Eleven HMCLs were compared with the native tumour. Four were similar to the tumour and seven were less well differentiated, in most cases in relation to their microvilli. With six HMCLs, tumours induced in nude mice were less well differentiated than the corresponding cell lines, whereas with four HMCLs, tumours were equally or better differentiated. However, in most nude mice tumours, typical mesothelial microvilli were present. These results show that cell lines established from malignant mesothelioma may exhibit dedifferentiated features. However, while the variability in ultrastructural differentiation may result from the culture microenvironment, it could also be related to the state of differentiation, of the native tumour sample and to tumour cell heterogeneity.     

Evaluation of the automated fluorescent analysis of the H-ras minisatellite after optimized PCR amplification in comparison with a standardized Southern blot technique

Determination of allele sizes? loss of heterozygosity or genetic instability at minisatellite VNTR loci, are routinely performed by the conventional Southern technique. We have investigated the potential use of automated DNA sequencer for the analysis of the H-ras minisatellite. We report the modifications of amplification parameters and electrophoresis conditions on the sequencer. Seventy-one colorectal carcinomas and the corresponding normal tissues were amplified with fluorescent-labeled primers, analyzed on sequencer, and concurrently controlled by Southern blotting. The results on sequencer showed that a Hydrolink matrix used in non-denaturing conditions and a specific analysis software facilitate a more accurate fragment size calculation.