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PubMed1996

Polymerase chain reaction (PCR) detection of Listeria monocytogenes in diluted milk and reversal of PCR inhibition caused by calcium ions.

DNA from Listeria monocytogenes was used as the model system from this investigation, with PCR primers based on the listeriolysin O gene. Under standard polymerase chain reaction (PCR) conditions and with no prior treatment, amplification failed in the presence of more than 5% milk. Since inhibition of the PCR occurred at the same milk concentrations with full fat, half fat and fat-free milk, inhibition was not attributed to the fat content of the milk. Calcium ions were, however, identified as a major source of PCR inhibition. The results demonstrated that the inhibitory effects of calcium ions and milk could be partially reversed by increasing the magnesium concentration in the reaction to well above the standard levels normally required for PCR. This work has important implications for the use of the PCR in the direct detection of food pathogens.

Animals↗

PubMed2006

Enumeration and detection of acetic acid bacteria by real-time PCR and nested PCR.

Acetic acid bacteria play a negative role in wine making because they increase the volatile acidity of wines. They can survive in the various phases of alcoholic fermentation and it is very important to control their presence and ulterior development. The main objective of the present work is to test fast, sensitive and reliable techniques such as real-time PCR (rt-PCR) and nested PCR for enumerating and detecting the presence of this bacterial group without plating. Primers were designed on the basis of the available 16S rRNA gene sequences and tested successfully with reference acetic acid bacteria strains. The usefulness of rt-PCR was demonstrated by comparing the results with traditional techniques (colony and microscope counting). The results were similar with all the techniques. Optimized rt-PCR enabled numbers between 10(7) and 10(1) cells mL(-1) to be enumerated, while nested PCR detected less than 10 cells mL(-1). Although this latter technique cannot be used for enumeration, it has several advantages in routine laboratory analysis.

Acetobacteraceae↗

PubMed1998

Genotypic characterization of Bradyrhizobium strains nodulating endemic woody legumes of the Canary Islands by PCR-restriction fragment length polymorphism analysis of genes encoding 16S rRNA (16S rDNA) and 16S-23S rDNA intergenic spacers, repetitive extragenic palindromic PCR genomic fingerprinting, and partial 16S rDNA sequencing.

We present a phylogenetic analysis of nine strains of symbiotic nitrogen-fixing bacteria isolated from nodules of tagasaste (Chamaecytisus proliferus) and other endemic woody legumes of the Canary Islands, Spain. These and several reference strains were characterized genotypically at different levels of taxonomic resolution by computer-assisted analysis of 16S ribosomal DNA (rDNA) PCR-restriction fragment length polymorphisms (PCR-RFLPs), 16S-23S rDNA intergenic spacer (IGS) RFLPs, and repetitive extragenic palindromic PCR (rep-PCR) genomic fingerprints with BOX, ERIC, and REP primers. Cluster analysis of 16S rDNA restriction patterns with four tetrameric endonucleases grouped the Canarian isolates with the two reference strains, Bradyrhizobium japonicum USDA 110spc4 and Bradyrhizobium sp. strain (Centrosema) CIAT 3101, resolving three genotypes within these bradyrhizobia. In the analysis of IGS RFLPs with three enzymes, six groups were found, whereas rep-PCR fingerprinting revealed an even greater genotypic diversity, with only two of the Canarian strains having similar fingerprints. Furthermore, we show that IGS RFLPs and even very dissimilar rep-PCR fingerprints can be clustered into phylogenetically sound groupings by combining them with 16S rDNA RFLPs in computer-assisted cluster analysis of electrophoretic patterns. The DNA sequence analysis of a highly variable 264-bp segment of the 16S rRNA genes of these strains was found to be consistent with the fingerprint-based classification. Three different DNA sequences were obtained, one of which was not previously described, and all belonged to the B. japonicum/Rhodopseudomonas rDNA cluster. Nodulation assays revealed that none of the Canarian isolates nodulated Glycine max or Leucaena leucocephala, but all nodulated Acacia pendula, C. proliferus, Macroptilium atropurpureum, and Vigna unguiculata.

Atlantic Islands↗

PubMed2003

Development of reverse transcription (RT)-PCR and real-time RT-PCR assays for rapid detection and quantification of viable yeasts and molds contaminating yogurts and pasteurized food products.

Reverse transcriptase PCR (RT-PCR) and real-time RT-PCR assays have been used to detect and quantify actin mRNA from yeasts and molds. Universal primers were designed based on the available fungal actin sequences, and by RT-PCR they amplified a specific 353-bp fragment from fungal species involved in food spoilage. From experiments on heat-treated cells, actin mRNA was a good indicator of cell viability: viable cells and cells in a nonculturable state were detected, while no signal was observed from dead cells. The optimized RT-PCR assay was able to detect 10 CFU of fungi ml(-1) in pure culture and 10(3) and 10(2) CFU ml(-1) in artificially contaminated yogurts and pasteurized fruit-derived products, respectively. Real-time RT-PCR, performed on a range of spoiled commercial food products, validated the suitability of actin mRNA detection for the quantification of naturally contaminating fungi. The specificity and sensitivity of the procedure, combined with its speed, its reliability, and the potential automation of the technique, offer several advantages to routine analysis programs that assess the presence and viability of fungi in food commodities.

Actins↗

PubMed1993

Establishment of a quality assurance program for human immunodeficiency virus type 1 DNA polymerase chain reaction assays by the AIDS Clinical Trials Group. ACTG PCR Working Group, and the ACTG PCR Virology Laboratories.

An independent quality assurance program has been established by the Virology Committee of the AIDS Clinical Trials Group in the Division of AIDS, National Institute of Allergy and Infectious Diseases, for monitoring polymerase chain reaction (PCR) assays for human immunodeficiency virus type 1 (HIV-1) DNA that are performed by 11 laboratories participating in multicenter clinical trials in the United States. To perform HIV-1 DNA PCR for patients in AIDS Clinical Trials Group protocols, each laboratory was initially certified by correctly testing a coded certification panel consisting of eight well-defined clinical whole-blood specimens and 30 cell pellets containing 0, 2, 5, 10, 20, or 50 8E5/LAV cells per 125,000 uninfected peripheral blood mononuclear cells. PCR was performed by one of two standardized commercial assays for amplification and nonisotopic detection of HIV-1 proviral DNA. For continuing certification, each laboratory must correctly test eight coded whole-blood samples per quarter and run three or four coded cell pellets and HIV-1 DNA copy standards with every PCR assay in real time. The PCR results for the coded pellets on each run are entered into an encrypted computer file, which immediately assesses the validity of the run. To date, 10 of 11 laboratories have correctly tested all HIV-1-positive and -negative samples in the initial certification panel on their first or second attempt. Subsequently, 9 of these 11 laboratories have continued to maintain their certified status. The use of commercial HIV-1 DNA PCR assays and an external quality assurance program have ensured that results from different laboratories are comparable and that problems with sensitivity and specificity are quickly identified.

Certification↗

PubMed1995

PCR ribotyping and arbitrarily primed PCR for typing strains of Clostridium difficile from a Polish maternity hospital.

Detection of the source of Clostridium difficile strains is of importance for the control of the nosocomial spread of this microorganism. For this purpose, vaginal and rectal swabs from 183 mothers, duplicate fecal samples (taken on days 1 and 4 after birth) from 183 neonates, and 94 environmental samples were cultured for C. difficile. The microorganism was never detected in the meconium obtained on day 1 after birth. On the other hand, an incidence of 17% C. difficile positivity was noted in the fecal samples obtained on day 4 after birth. Forty-two percent of the 31 colonized neonates had been delivered with complications. The bacteria were never encountered in the rectal swabs of the mothers, and C. difficile was identified in only one vaginal swab. In contrast, 13% of the environmental samples were positive for C. difficile. No major difference was encountered between patient and environmental isolates with respect to toxigenicity (58 to 65% toxigenic isolates). All strains were subsequently typed by PCR amplification of the 16S-23S ribosomal intergenic spacer regions and by arbitrarily primed PCR (AP-PCR) with different primers and combinations thereof. All environmental isolates and 11 of 31 neonatal strains were of a single type. The vaginal strain was unique, and among the maternity ward- and neonate-related isolates, only two additional AP-PCR types were identified. When a collection of C. difficile strains from patients hospitalized in other institutions and suffering from antibiotic-associated diarrhea or pseudomembranous colitis was analyzed in a similar manner, it appeared that the strain from the maternity ward was unique. The other strain commonly encountered among the neonates was also identified frequently among the isolates from patients with antibiotic-associated diarrhea or pseudomembranous colitis, indicating its general occurrence. On the basis of both epidemiological studies and PCR-mediated genotyping, it was shown that the environment and not the birth canal is the major source of C. difficile acquisition by neonates in this maternity hospital setting. Furthermore, AP-PCR appears to be a fast and useful method for epidemiologically relevant typing of C. difficile isolates.

Bacterial Typing Techniques↗

PubMed1996

Monitoring of cytomegalovirus infection and disease in bone marrow recipients by reverse transcription-PCR and comparison with PCR and blood and urine cultures.

Preemptive therapy is a promising strategy for the prevention of serious cytomegalovirus (CMV) disease after bone marrow (BM) transplantation but requires relevant diagnostic tests. We compared the clinical value of a reverse transcription (RT)-PCR method, which detected a late viral mRNA in peripheral blood leukocytes (PBL), with a PCR method that detected the viral DNA in PBL and with viral culture from leukocytes and urine for the diagnosis of symptomatic CMV infection after BM transplantation. Forty-five consecutive BM recipients were prospectively tested at weekly intervals by the four methods. CMV infection, demonstrated either by the culture of CMV or by repeated detection of viral DNA, was observed in 28 patients, but only 14 developed CMV-related clinical symptoms. The clinical sensitivity and specificity of each technique for detection of symptomatic infection were, respectively, 36 and 74% for urine culture, 43 and 84% for leukocyte culture, 100 and 65% for PCR, and 71 and 94% for RT-PCR. Although PCR detection of DNA in PBL was the earliest and most sensitive technique for the diagnosis of CMV infection, RT-PCR was more predictive of the onset of CMV-related clinical symptoms. These data suggest that both molecular methods should be used for identifying BM recipients at highest risk of CMV disease.

Adolescent↗

PubMed2002

Comparison of quantitative competitive PCR with LightCycler-based PCR for measuring Epstein-Barr virus DNA load in clinical specimens.

The aim of this study was to develop a LightCycler-based real-time PCR assay for monitoring the Epstein-Barr virus (EBV) DNA load in unfractionated whole blood. This assay was compared with quantitative competitive PCR (Q-PCR) for EBV. The LightCycler-based assay was highly sensitive and reproducible when quantifying plasmid DNA in either the presence or absence of healthy donor blood DNA. Amplifying plasmid DNA in DNA backgrounds from different donors slightly increased the variation of quantification, indicating that clinical specimen DNA has an influence on quantification. In most transplant recipients, a good correlation was observed between EBV DNA load dynamics determined by LightCycler and Q-PCR in follow-up samples, although the correlation between absolute values of EBV DNA loads was weak and occasional samples were false negative in the LightCycler assay. In 253 cross-sectional blood samples from patients with Burkitt's lymphoma, infectious mononucleosis, or human immunodeficiency virus infection, a weak but significant correlation between the two methods was found (r(2) = 0.37, P < 0.001). Our results indicate that the clinical specimen DNA background may influence the absolute values of EBV DNA load in LightCycler analyses but that this effect is rare. LightCycler PCR is very well suited for monitoring of EBV DNA load dynamics, and its diagnostic value is comparable to that of Q-PCR. To avoid false negativity or underestimation of viral load, future internal calibration of the LightCycler is recommended. This would also enhance EBV load assay standardization and interinstitute comparisons.

DNA, Viral↗

PubMed2004

Evaluation of a bedside immunochromatographic test for detection of adenovirus in respiratory samples, by comparison to virus isolation, PCR, and real-time PCR.

An immunochromatography (IC) kit for human adenovirus (HAdV) was evaluated with 138 patient nasopharyngeal samples. The samples were collected at a sentinel clinic in Japan from January through June 2003. Patients were diagnosed by clinical manifestation of pharyngoconjunctival fever (n = 38) or exudative tonsillitis (n = 100). The IC kit was positive for 84% (116 of 138) of patients diagnosed at bedside. The remaining extract solution of the IC kit test was transferred into maintenance medium and tested via laboratory diagnoses. The IC kit had 95% sensitivity (116 of 122 patients) with HAdV isolation (isolation) as the standard and 91% sensitivity (116 of 128 patients) with PCR as the standard. All of the IC kit-positive samples were isolation and PCR positive. Similarly, all the isolation-positive samples were PCR positive. Twenty-two IC kit-negative samples were evaluated by real-time PCR. Six samples were IC kit negative and isolation positive and contained 3.8 x 10(7) to 2.5 x 10(9) copies of the HAdV genome/ml. Five samples that were only PCR positive contained 3.0 x 10(4) to 3.8 x 10(5) copies of the HAdV genome/ml, but one sample was real-time PCR negative. We conclude that the IC kit is a useful bedside diagnostic tool for HAdV infections because it has 95% sensitivity (compared to isolation), but a negative result does not always rule out HAdV infection.

Adenovirus Infections, Human↗

PubMed2006

Detection of DeltaF508del using quantitative real-time PCR, comparison of the results obtained by fluorescent PCR.

OBJECTIVE: Cystic fibrosis (CF) is the most common autosomal recessive genetic disorder in the Caucasian population. The molecular diagnosis is difficult since there are about 1,000 mutations in the CF transmembrane regulator gene. The DeltaF508del is the cause of the CF in 64% of the cases in Hungary. Our aim was to compare two polymerase chain reaction (PCR)-based method for the detection of DeltaF508del. METHODS: One hundred and sixteen DNA samples isolated from different tissues (84 blood samples, 18 chorionic villus samples and 14 amniotic fluid samples) were involved in the study. Fluorescent PCR with DNA fragment analysis and quantitative real-time PCR with melting curve analysis were performed on the DNA samples for the detection of DeltaF508del. RESULTS: Sixty-five healthy normal samples, 43 heterozygous samples, 6 DeltaF508del homozygous samples and 2 DeltaF508C homozygous samples were detected by using quantitative real-time PCR combined with melting curve analysis. The fluorescent PCR method did not detect the DeltaF508C mutation and these two samples were diagnosed as normal healthy ones. CONCLUSIONS: The quantitative real-time PCR with melting curve analysis is a reliable and fast method for the detection of DeltaF508del. The results are ready in 1 h following the DNA isolation. The applied primer-probe set with melting curve analysis gives additional information for the presence of other mutations in the DeltaF508del region.

Cystic Fibrosis↗

PubMed1998

Restriction digest PCR (RD-PCR) for the analysis of gene mutations. Application to Ki-ras.

The Kirsten-ras (onco)gene codes for a GTP-binding membrane protein that is involved in signal transduction. Activated ras triggers a cascade of protein-phosphorylations that ultimately lead to cell proliferation. Ras-mutations are the main cause for adenocarcinomas of the pancreas besides some mutations in the tumor suppressor gene p53 and the c-erbB-2 oncogene. The site of ras mutations in pancreatic cancer is restricted to codon 12 that normally encodes a glycine. For analysis of codon-12 mutations, DNA is extracted from cells in pancreatic fluid and amplified by PCR. Because most of these cells originate from normal tissue with only a few tumor cells in the fluid, "enrichment PCR" must be utilized: In a first round of the PCR, ras sequences from all cells are amplified. By utilizing an appropriate restriction enzyme, wild-type sequences can be digested and the remaining fragments containing mutated sequences be amplified again. An artificial restriction site must be introduced by the 5'primer (...GGA CCT GGT...) for an enzyme (BstNI) (5'CC!WGG 3') to differentiate between wild-type sequence (...GGA GCT GGT...) (during amplification, the G is replaced by a C) and mutated sequences (_...GGA GCT (GTT), (CGT), (CCT), etc.). The necessary manipulations pose a considerable risk for contamination for the second round of the PCR procedure. Therefore, we considered whether it would be feasible to perform the restriction digest simultaneously with the first PCR reaction, and avoiding the second round altogether. The results of our experiments demonstrate that one tumor cell in 1000 normal cells can be determined readily, paralleling the results with the original two step-assay. The restriction enzyme used to enrich mutated sequences is stable long enough to be included into the PCR procedure. By this, wild-type sequence amplicons are digested while they are formed and mutated sequences can be enriched selectively.

Base Sequence↗

PubMed2001

Enterobacterial repetitive intergenic consensus sequence-based PCR (ERIC-PCR); its ability to differentiate Streptococcus pyogenes strains and applicability to the study of outbreaks of streptococcal infection.

We evaluated the ability of enterobacterial repetitive intergenic consensus sequence-based PCR (ERIC-PCR) to differentiate 95 Streptococcus pyogenes strains with M or T serotypes isolated from sporadic streptococcal infections as compared with M or T serotypings and pulsed-field gel electrophoresis (PFGE). Although the ERIC-PCR had less discriminatory power, defined as the ability to divide the strains with the same serotypes into the different sub-types, than PFGE, it consistently classified the strains into 16 patterns with a high correlation with M or T serotyping. The PCR method further discriminated 4 M or T serotypes into sub-types. The application of ERIC-PCR to 5 outbreaks of streptococcal infection produced the results that agreed closely with those of T serotyping and PFGE. ERIC-PCR has sufficient discriminatory power and is a quick and relatively easy technique, making it useful for routine epidemiological investigations.

Bacterial Typing Techniques↗

PubMed1996

Multiple fluorescence-based PCR-SSCP analysis using internal fluorescent labeling of PCR products.

The method to internally label PCR products with multiple colored fluorescent dyes was developed and applied to multiple fluorescence-based PCR single-stranded conformational polymorphism (MF-PCR-SSCP) analysis. PCR-amplified fluorescent DNA fragments, which were internally labeled by adding fluorescent dUTPs ([F]dUTPs) to the PCR mixture, were heat-denatured and applied to a nondenaturing polyacrylamide gel (SSCP gel) set on an automated DNA sequencer with a gel temperature-controlling system. The image data were analyzed by GENESCAN 672 software. In spite of differences in species and amount of integrated [F]dUTPs, the SSCP profiles were not significantly affected, even by the different labeling methods used-internal labeling or post-labeling at the 3' ends-in regard to the three different [F]dUTPs examined. However, the salt concentration of the solution containing the DNA samples affected the SSCP profiles. The internally labeled [F]dUTP-containing DNA fragments beyond 1000 bp in length were successfully digested with restriction endonucleases and subjected to SSCP analysis. MF-PCR-SSCP analysis with internal fluorescence labeling affords a simple and sensitive method to detect alterations in DNA sequences.

DNA Mutational Analysis↗

PubMed1998

PCR bias toward the wild-type k-ras and p53 sequences: implications for PCR detection of mutations and cancer diagnosis.

PCR-based cancer diagnosis requires detection of rare mutations in k-ras, p53 or other genes. The assumption has been that mutant and wild-type sequences amplify with near equal efficiency, so that they are eventually present in proportions representative of the starting material. Work on factor IX suggests that this assumption is invalid for one case of near-sequence identity. To test the generality of this phenomenon and its relevance to cancer diagnosis, primers distant from point mutations in p53 and k-ras were used to amplify wild-type and mutant sequences from these genes. A substantial bias against PCR amplification of mutants was observed for two regions of the p53 gene and one region of k-ras. For k-ras and p53, bias was observed when the wild-type and mutant sequences were amplified separately or when mixed in equal proportions before PCR. Bias was present with proofreading and non-proofreading polymerases. Mutant and wild-type segments of the factor V, cystic fibrosis transmembrane conductance regulator and prothrombin genes were amplified and did not exhibit PCR bias. Therefore, the assumption of equal PCR efficiency for point mutant and wild-type sequences is invalid in several systems. Quantitative or diagnostic PCR will require validation for each locus, and enrichment strategies may be needed to optimize detection of mutants.

Base Sequence↗

PubMed2004

Development and comparison of the real-time amplification based methods--NASBA-Beacon, RT-PCR taqman and RT-PCR hybridization probe assays--for the qualitative detection of sars coronavirus.

The aim of this study was to develop a rapid, sensitive and robust procedure for the qualitative detection of SARS coronavirus RNA. Three unique detection formats were developed for real-time RNA amplification assays: a post amplification detection step with a virus-specific internal capture probe based on Taqman (RT-PCR TaqMan assay), hybridization probe (RT-PCR hybridization probe assay) and a real-time assay with virus-specific molecular beacon probes (NASBA-Beacon assay). The analytical sensitivity or reproducibility of the test results among those three assays was compared. All assays yielded results by detecting SARS coronavirus targeting the BNI-1 region in less than 2 hours. RNA detection by all the formats was unaffected by the presence of human sputum. The limits of detection were at least 10 copies of input RNA for both RT-PCR formats (RT-PCR TaqMan and RT-PCR hybridization probe assays), while the NASBA-Beacon assay could detect as little as 1 copy per reaction, with high reproducibility of the coefficient of variation (CV) of <10. These results demonstrate that real-time NASBA provides a rapid and sensitive alternative to RT-PCR for the routine qualitative assay of sputum for SARS corona viral RNA detection.

Computer Systems↗

PubMed2005

[Analysis of polymorphism on exon 2 of SLA-DRB in Wuzhishan, Erhualian and Pietrain pigs with PCR-RFLP and PCR-SSCP].

Exon 2 of SLA-DRB gene in three strains of pigs was genotyped by PCR-RFLP and PCR-SSCP methods. The strains involved were Wuzhishan, Erhualian and Pietrain, and the numbers of them were 17, 28 and 28, respectively. After genotyping by PCR-RFLP with Msp I, all pigs showed the same band pattern (143 bp/102 bp) named M. However, four kinds of band patterns were created by Rsa I, that were A:141 bp/93 bp/11 bp, B:111 bp/69 bp/54 bp/11 bp, C:180 bp/54 bp/11 bp and D:93 bp/48 bp/39 bp/54 bp/11 bp. There were different pattern types in various pigs, AA and BB in Wuzhishan pigs, AA, BB and AB in Erhualian pigs, AA, CC and BD in Pietrain pigs. In each strain, A was the dominant band pattern, its frequency in Wuzhishan, Erhualian and Pietrain pigs were 0.69, 0.73 and 0.82, respectively. There were no significant differences in the frequency of A band pattern among these three strains. After genotyping by PCR-SSCP, seven pattern types (alphaalpha, alphadelta, betabeta, gammagamma, alphagamma, deltadelta and betaepsilon) were observed in these three populations. There were alphaalpha, alphadelta and betabeta in Wuzhishan pigs, alphaalpha, gammagamma and alphagamma in Erhualian pigs, and alphaalpha, deltadelta, alphadelta, betaepsilon and betabeta in Pietrain pigs. In each breed, the frequency of a band pattern was the highest in all defined bands. The frequency of delta band pattern followed to alpha band pattern in the populations of Wuzhishan and Pietrain pigs, corresponding to that, the frequencies of alphadelta pattern type were maximal in these two populations. The frequencies of all pattern types analyzed by PCR-RFLP and PCR-SSCP were Hardy-Weinberg Equilibrium in Erhualian populations; however, the same results did not appear in the other two populations.

Animals↗

PubMed2006

Detection of human adenoviruses and enteroviruses in Korean oysters using cell culture, integrated cell culture-PCR, and direct PCR.

Oysters are known to be carriers of food-born diseases, but research on viruses in Korean oysters is scarce despite its importance for public health. We therefore tested oysters cultivated in Goheung, Seosan, Chungmu, and Tongyeong, for viral contamination using cell culture and integrated cell culture PCR (ICC-PCR) with Buffalo green monkey kidney (BGMK) and human lung epithelial (A549) cells. Additional screens via PCR, amplifying viral nucleic acids extracted from oysters supplemented our analysis. Our methods found 23.6%, 50.9%, and 89.1% of all oysters to be positive for adenoviruses when cell culture, ICC-PCR, and direct PCR, respectively, was used to conduct the screen. The same methodology identified enteroviruses in 5.45%, 30.9%, and 10.9% of all cases. Most of the detected enteroviruses (81.3%) were similar to poliovirus type 1; the remainder resembled coxsackievirus type A1. A homology search with the adenoviral sequences revealed similarities to adenovirus subgenera C (type 2, 5, and 6), D (type 44), and F (enteric type 40 and 41). Adenovirus-positive samples were more abundant in A549 cells (47.3%) than in BGMK cells (18.2%), while the reverse was true for enteroviruses (21.8% vs. 14.5%). Our data demonstrate that Korean oysters are heavily contaminated with enteric viruses, which is readily detectable via ICC-PCR using a combination of A549 and BGMK cells.

Adenoviridae↗

PubMed1995

Analysis of rearranged T-cell receptor beta-chain genes by polymerase chain reaction (PCR) DNA sequencing and automated high resolution PCR fragment analysis.

Polymerase chain reaction (PCR)-directed amplification and sequencing of rearranged immune genes for identification of clone-specific markers are increasingly being used in acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL) patients instead of the time consuming and labor intensive Southern analysis. In previous reports, no single common V beta and J beta sequence had been identified that allowed reliable amplification of the majority of rearranged T-cell antigen receptor (TCR)-beta V-D-J junctions at the DNA level because of the relatively large number of possible TCR-beta variable (V beta) and joining (J beta) gene segments involved in the rearrangement processes. In the present study we designed highly degenerate PCR primers directed against conserved sequences of the J beta genes. IN combination with a previously published consensus V beta primer, these J beta primers specifically amplify TCR- beta V-N(D)N-J junctions from genomic DNA. Using this approach we studied DNA extracted from biopsy material of nine patients with T-cell lymphoproliferative disorders, one c-ALL patient, and five patients with nonmalignant diseases. T-cell lines Molt 3, Jurkat, and HM 2 served as monoclonal controls. Individual PCR products were sequenced after cloning. The nucleotide sequences of 96 randomly chosen recombinant vectors were determined. In the polyclonal controls all analyzed clones differed in their TCR-beta V-N(D)N-J junctions. In the T-cell lines, in all of the T-cell malignancies, and in the c-ALL, monoclonal PCR products could be identified by demonstration of clonally restricted V-N(D)N-J junctions. The PCR results were confirmed by automated fluorescence quantification and size determination of PCR products after separation in a high-resolution polyacrylamide gel. The procedure allows rapid and specific characterization of clonal TCR-beta rearrangements from genomic DNA and will significantly simplify current experimental approaches to identify and to quantitate malignant T cells during initial staging and follow-up of T-lineage NHL and ALL patients.

Automation↗