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Results for “Quantitative PCR”

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At least 1,261 records · Page 70Linked to original sources
PubMed2001

[Expression of monocyte chemotacticp protein-1 in the eutopic endometrium of women with endometriosis].

OBJECTIVE: To examine the expression of monocyte chemotactic protein-1 (MCP-1) messenger ribonucleic acid (mRNA) in the endometrium of patients with and without endometriosis. METHODS: A reverse transcription-polymerase chain reaction (RT-PCR) method was utilized to examine and quantitate MCP-1 mRNA expressions and levels in the eutopic endometrium. Thirty patients with endometriosis were included as study group, and 20 patients without endometriosis selected as control group. RESULTS: 26 (87%) of 30 samples of endometrium from patients with endometriosis expressed MCP-1 mRNA, 19 of which were strong expression, while 15 (75%) of 20 samples of endometrium from patients without endometriosis express MCP-1 mRNA (P > 0.05). When endometriosis were grouped by Revised American Fertility Society (RAFS) stages, there was no obvious correlation between stage and MCP-1 mRNA expression level (P > 0.05). Semi-quantitative PCR showed the expression level of MCP-1 in endometrium of patients with endometriosis were higher than those of patients without endometriosis (0.746 +/- 0.345 Vs 0.460 +/- 0.341 respectively, P < 0.05). CONCLUSIONS: The MCP-1 mRNA is over expressed in the eutopic endometrium from patients with endometriosis, which may play some roles on the pathogenesis of endometriosis.

Adult↗
PubMed2003

A chimeric mouse model established by allogenic in utero transplantation.

In utero stem cells transplantation is a promising approach to the prenatal treatment of diseases. In order to investigate the fate of the stem cells after in utero transplantation, we have established a chimeric mouse model with the method of in utero transplantation. Mononuclear cells (including stem cells/progenitor cells) derived from male mouse bone marrow were injected into fetal mouse peritoneal cavity during the pre-immune period. The donor cells in the circulatory blood of female recipients were identified by fluorescence in situ hybridization (FISH), and the Y-chromosome specific DNA was detected by PCR as well as real-time quantitative PCR after the recipient mice were born. The results showed that a total of 4 female recipient mice were chimeric in their peripheral blood. Significantly, the donor cells in three chimeric mice persisted up to six months.

Animals↗
PubMed1999

Persistent alterations in T-cell repertoire, cytokine and chemokine receptor gene expression after 1 year of highly active antiretroviral therapy.

OBJECTIVES: To examine T-cell repertoire modifications, the evolution of T-helper (TH)1/TH2 cytokine imbalance and modifications in chemokine receptor expression when the viral load is decreased by 2-3 log10 copies/ml under highly active antiretroviral therapy (HAART). DESIGN: Sixteen patients previously treated with zidovudine and lamivudine, with CD4 cells below 300 x 10(6)/l and viraemia above 30000 copies/ml were treated by saquinavir and ritonavir together with both reverse transcriptase (RT) inhibitors (ANRS 069 trial). T-cell repertoire, chemokine receptor and lymphokine expression were studied from peripheral blood mononuclear cells sampled at weeks 0, 24 and 48. METHODS: T-cell repertoire study was carried out using the Immunoscope method. Interleukin (IL)-12 receptor beta2, CC-chemokine receptor (CCR)-3, CXC-chemokine receptor-4 and CCR-5 expression in CD4+ cells was measured by kinetic quantitative PCR and IL-2, IL-4, IL-10, IL-13, interferon (IFN)-gamma were measured using a quantitative RT-PCR assay with homologous internal standards. RESULTS: Repertoire alterations were more frequent in CD4- than in CD4+ cells and persisted despite undetectable viraemia. Increased CCR-3 expression and spontaneous IFN-gamma as well as mitogenic induced IL-13 were observed at baseline and decreased slightly under HAART. CONCLUSION: The CD8+ cell repertoire alterations were profound, whereas the CD4+ cell alterations were moderate and both persisted unchanged under HAART. The TH1/TH2 imbalance was more related to TH2 over-expression than to TH1 deficiency and persisted for at least 1 year under HAART.

Adult↗
PubMed2005

An in vitro model for studying vascular injury after laser microdissection.

We have developed an in vitro model for studying vascular injury. After 7-10 days in a three-dimensional collagen gel culture, capillary-like tubes were formed in the collagen gels. We injured these capillary-like tubes with a laser microdissection system or a scrape method with razors and then examined the collagen gel culture by phase contrast and electron microscopy. After laser injury, profuse necrotic cells were observed around the injured capillary-like tubes and within the tubular lumen compared to the razor injury. We then isolated total RNA from these cultures and prepared cDNA for investigations by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). Quantitative real time RT-PCR revealed the up-regulation of transcription factor early growth response-1 (Egr-1) after both laser and razor injury, accompanied by the up-regulation of fibroblast growth factor-2 (FGF-2), a proangiogenic factor downstream of Egr-1. The effective laser energy is concentrated on the minute focal spot only. These methods provide a useful in vitro model for studying vascular injury.

Animals↗
PubMed2006

Application of real-time PCR to quantify hepatitis B virus DNA in chronic carriers in The Gambia.

BACKGROUND/AIM: The study aimed at developing a real-time quantitative PCR assay to monitor HBV serum virus load of chronic carriers enrolled in therapeutic trials. METHOD: Quantitative real-time PCR assay was carried out using SYBR-Green signal detection and primers specific to the S gene. Thermal cycling was performed in an ABi 5700 sequence detection system. The assay was calibrated against an international HBV DNA standard and inter- and intra-assay reproducibility determined. Levels of viral load were monitored for 1-year in lamivudine treated carriers. Correlation between HBV DNA levels and HBeAg sero-status was determined in untreated carriers. RESULTS: The qPCR assay showed good intra- and inter-assay reproducibility over a wide dynamic range (1.5 x 103 to 1.5 x 108 copies/mL) and correlated well with those from a commercial assay (r = 0.91, (p < 0.001). Viral load levels dropped dramatically but temporarily during and after a short course of lamivudine therapy. HBV DNA was a more reliable indicator of the presence of virus than HBe antigen and was detected in 77.0% (161/209) of HBeAg negative and in all HBeAg positive carriers. CONCLUSION: This method is reliable, accurate, and reproducible. HBV DNA Quantification by qPCR can be used to monitor the efficacy of HBV therapy and useful in understanding the natural history of HBV in an endemic area.

Adolescent↗
PubMed2003

Quantitative real time polymerase chain reaction for measurement of human interleukin-5 receptor alpha spliced isoforms mRNA.

BACKGROUND: Expression of human Interleukin-5 receptor alpha (hIL-5Ralpha) is controlled by alternative splicing, which generates two different transcripts encoding a membrane-anchored and a soluble form of the receptor, respectively. Although the study of the expression and regulation of hIL-5Ralpha is of crucial importance in the field of immunological processing, methods and techniques until now described lack sufficient sensitivity for detection of small differences in the expression of these isoforms. The aim of this study was to develop a reliable and sensitive real-time quantitative PCR assay to analyse the expression level of each isoform. METHODS: For the quantitative real-time PCR assay, two standard curves specific for each splice variant were constructed. PCR amplifications were performed on CDNA from peripheral blood, eosinophilic chronic rhinosinusitis and normal nasal tissue using a common forward and two specific reverse primers, in combination with SYBR Green I as the detection format. RESULTS AND CONCLUSION: We have developed an accurate and reliable assay for quantification of interleukin-5 receptor alpha mRNA isoforms over a broad dynamic range of input molecules. Importantly, excess of one isoform did not influence accurate quantification of the other isoform. Quantification of hIL-5Ralpha variants in human samples demonstrated an overexpression of both membrane-anchored and soluble encoding variants in eosinophilic chronic rhinosinusitis tissue and peripheral blood in patients with eosinophilic chronic rhinosinusitis compared to healthy subjects. The implementation of this assay will allow a better understanding of the regulatory mechanisms of the hIL-5Ralpha gene and hence its role in the pathogenesis of chronic inflammatory diseases.

Alternative Splicing↗
PubMed2001

Expression profiles of voltage-gated Na(+) channel alpha-subunit genes in rat and human prostate cancer cell lines.

BACKGROUND: Voltage-gated Na(+) channel (VGSC) activity has been implicated in prostate cancer (PC) metastasis. Although VGSCs can occur as multiple-subunit assemblies, the alpha-subunits (VGSCalphas) alone can encode functional channels. The VGSCalpha gene(s) responsible for the functional VGSCalpha expression in strongly metastatic PC cell lines is not known. METHODS: Two reverse transcription-PCR (RT-PCR) methods, degenerate primer screening and a novel semi quantitative PCR (SQT-PCR) technique, were used. These methods enabled a detailed qualitative and quantitative investigation of VGSCalpha mRNA expression in rat (MAT-LyLu/AT-2) and human (PC-3/LNCaP) PC cells of markedly different metastatic potential. RESULTS: Expression of eight different VGSCalpha genes (SCN1A-4A, SCN7A-9A, and SCN11A) was determined in the PC cell lines. Most were expressed as multiple splice variants. SQT-PCR results were consistent with a basal level of VGSCalpha mRNA expression occurring in weakly metastatic (AT-2/LNCaP) cells, and this being greatly elevated in cells of stronger metastatic potential (MAT-LyLu/PC-3), primarily due to the elevated expression of the SCN9A gene (also termed PN1/hNe-Na). CONCLUSIONS: (1) Several VGSCalpha genes and their splice variants are expressed similarly in both rat and human PC cell lines. (2) Expression levels are much higher in the strongly metastatic (MAT-LyLu/PC-3) cells. (3) Levels of SCN9A mRNA specifically are predominant in MAT-LyLu and PC-3 cells; thus, SCN9A is highly likely to be the main source of the functional VGSC detected.

Animals↗
PubMed2002

[Real-time quantitative RT-PCR for the detection of bcl-2 mRNA expression].

OBJECTIVE: To establish a real-time quantitative RT-PCR method for the detection of expression of bcl-2 mRNA. METHODS: The vector containing bcl-2 gene as standard template was constructed with T-A cloning technique. The fluorogenic probe (i.e.,Taq man probe) was used to establish a real-time RT-PCR. bcl-2 mRNA expression level in Burkitt's lymphoma pre-and post-treated with bcl-2 antisense phosphothioate oligodeoxynucleotides (AS-PS-ODN) was determined with real-time quantitative RT-PCR, also with semi-quantitative RT-PCR. RESULTS: The expression of bcl-2 mRNA in Burkitt's lymphoma treated with bcl-2 AS- PS-ODN decreased significantly and no changes of bcl-2-mRNA expression in group treated with nonsense ODN were noticed. The semi-quantitative RT-PCR results also demonstrated that bcl-2 level varied as detected with real-time fluorogenic quantitative RT-PCR, but less sensitive and accurate. CONCLUSION: Detection of bcl-2 mRNA expression with the fluorogenic real-time quantitative RT-PCR is more accurate and sensitive than semi-quantitive RT-PCR.

Electrophoresis, Agar Gel↗
PubMed2003

Neurokinin 1 receptor and relative abundance of the short and long isoforms in the human brain.

Substance P exerts its various biochemical effects mainly via interactions through neurokinin-1 receptors (NK1). Recently, the NK1 receptor has attracted considerable interest for its possible role in a variety of psychiatric disorders including depression and anxiety. However, little is known regarding the anatomical distribution of NK1 in the human central nervous system (CNS). Riboprobe in situ hybridization, quantitative PCR and in vitro autoradiography were performed. Highest NK1 mRNA levels were localized in the locus coeruleus and ventral striatum, while moderate hybridization signals were observed in the cerebral cortex (most abundant in the visual cortex), hippocampus and different amygdaloid nuclei. Very low levels of the NK1 mRNA were detected in the cerebellum and thalamus. In view of the existence of a long and short isoform of the NK1 receptor, it was of interest to assess whether there was a differential distribution of the two splice variants in the human CNS and peripheral tissues. A quantitative TaqMan PCR analysis showed that the long NK1 isoform was the most prevalent throughout the human brain, while in peripheral tissues the truncated form was the most represented. 3H-Substance P autoradiography revealed a good correlation between receptor binding sites and NK1 mRNA expression throughout the brain, with the highest levels of binding in the locus coeruleus. These results provide the anatomical evidence that the NK1 receptors have a strong association with neuronal systems relevant to mood regulation and stress in the human brain, but do not suggest a region-specific role of the two isoforms in the CNS.

Adult↗
PubMed2006

Large fragment Bst DNA polymerase for whole genome amplification of DNA from formalin-fixed paraffin-embedded tissues.

BACKGROUND: Formalin-fixed paraffin-embedded (FFPE) tissues represent the largest source of archival biological material available for genomic studies of human cancer. Therefore, it is desirable to develop methods that enable whole genome amplification (WGA) using DNA extracted from FFPE tissues. Multiple-strand Displacement Amplification (MDA) is an isothermal method for WGA that uses the large fragment of Bst DNA polymerase. To date, MDA has been feasible only for genomic DNA isolated from fresh or snap-frozen tissue, and yields a representational distortion of less than threefold. RESULTS: We amplified genomic DNA of five FFPE samples of normal human lung tissue with the large fragment of Bst DNA polymerase. Using quantitative PCR, the copy number of 7 genes was evaluated in both amplified and original DNA samples. Four neuroblastoma xenograft samples derived from cell lines with known N-myc gene copy number were also evaluated, as were 7 samples of non-small cell lung cancer (NSCLC) tumors with known Skp2 gene amplification. In addition, we compared the array comparative genomic hybridization (CGH)-based genome profiles of two NSCLC samples before and after Bst MDA. A median 990-fold amplification of DNA was achieved. The DNA amplification products had a very high molecular weight (> 23 Kb). When the gene content of the amplified samples was compared to that of the original samples, the representational distortion was limited to threefold. Array CGH genome profiles of amplified and non-amplified FFPE DNA were similar. CONCLUSION: Large fragment Bst DNA polymerase is suitable for WGA of DNA extracted from FFPE tissues, with an expected maximal representational distortion of threefold. Amplified DNA may be used for the detection of gene copy number changes by quantitative realtime PCR and genome profiling by array CGH.

Carcinoma, Non-Small-Cell Lung↗
PubMed2006

PCR-based detection is unable to consistently distinguish HIV 1LTR circles.

Quantitative PCR methods are routinely used to measure multiple HIV cDNA forms, including linear cDNA, early and late reverse transcripts, 2LTR circles, and integrated provirus. PCR-based methods for the detection of 1LTR circles have been proposed, but are complicated by the inherent homology of the LTR sequence present in all cDNA forms. Amplicons with variable lengths of homology showed that it is difficult to discriminate 1LTR circles faithfully from other cDNA forms. Addition of formamide, DMSO, or glycerol did not eliminate amplification of spurious products. Thus, detection of 1LTR circles by PCR is not reliable.

DNA, Circular↗
PubMed2005

Sequence diversity in the glycoprotein B gene complicates real-time PCR assays for detection and quantification of cytomegalovirus.

Real-time quantitative PCR systems (Q-PCR) for the rapid detection and quantification of microorganisms in clinical specimens employ oligodeoxyribonucleotide primers and probes for specificity, which makes them vulnerable to false negatives caused by sequence diversity in the template. Schaade et al. (J. Clin. Microbiol. 39:3809, 2001) reported a sequence variant (C630T) in the cytomegalovirus (CMV) glycoprotein B (gB) gene that, although detectable in their Q-PCR assay, could not be accurately quantified. In an effort to evaluate the impact of CMV sequence variants in our patient population by use of a similar Q-PCR assay, we surveyed 54 isolates of CMV, each from a different patient. We detected evidence for the C630T variant in 4 of 54 (7.4%) patients. Furthermore, isolates from two additional patients were completely negative in the test. Sequencing of these false-negative isolates revealed multiple mutations within the probe hybridization sites. A Q-PCR that targeted the CMV polymerase gene instead of gB detected all 54 isolates. We suggest that Q-PCR assays for viral load be rigorously tested on large panels of viral isolates to assess the impact of sequence diversity on detection as well as quantification.

Base Sequence↗
PubMed2001

Detection of small sequence differences using competitive PCR: molecular monitoring of genetically improved, mercury-reducing bacteria.

A quantitative PCR approach is presented to detect small genomic sequence differences for molecular quantification of recombinant DNA. The only unique genetic feature of the mercury-reducing, genetically improved Pseudomonas putida KT2442::mer73 available to distinguish it from its native mercury-resistant relatives is the DNA sequence crossing the border of the insertion site of the introduced DNA fragment. The quantification assay is a combination of specific PCR amplification and temperature gradient gel electrophoresis (TGGE). Gene quantification is provided by a competitively co-amplified DNA standard constructed by point mutation PCR. After computing the denaturation behavior of the target DNA stretch, a single base difference was introduced to achieve maximum migration difference in TGGE between the original target DNA and the modified standard without altering the PCR amplification efficiency. This competitive PCR strategy is a highly specific and sensitive way to detect small sequence differences and to monitor recombinant DNA in effluxes of biotechnological plants.

Base Sequence↗
PubMed2025

Comprehensive analysis of diagnostic biomarkers related to histone acetylation in acute myocardial infarction.

BACKGROUND: Acute myocardial infarction (AMI) has become a serious disease that endangers human health, with high morbidity and mortality. Numerous studies have reported histone acetylation can result in the occurrence of cardiovascular diseases. This article aims to explore the potential biomarkers of histone acetylation regulatory genes (ARGs) in AMI patients. METHODS: Five AMI datasets were downloaded from the Gene Expression Omnibus (GEO) database. Next, ARG-related genes were gathered by gene set variation analysis (GSVA) and Spearman's correlation analysis. Subsequently, weighted gene co-expression network analysis (WGCNA) was performed to identify the module genes related to histone acetylation regulation. In the GSE60993 and GSE48060 datasets, the common differentially expressed genes (DEGs) between AMI and control samples were screened. Importantly, the intersecting genes were obtained by overlapping ARGs-related genes, common DEGs, and module genes. Then, the biomarkers in AMI were determined by machine learning, receiver operating characteristic (ROC) curves, and quantitative PCR (qPCR). In addition, immune analysis, drug prediction, molecular docking, and the lncRNA-miRNA-mRNA regulatory network targeting the biomarkers were analyzed, respectively. RESULTS: Here, a total of 18 intersecting genes were identified by overlapping 7,349 ARGs-related genes, 5,565 module genes, and 25 common DEGs. Further, five biomarkers (AQP9, HLA-DQA1, MCEMP1, NKG7, and S100A12) were obtained, and a nomogram was constructed and verified based on these biomarkers. Notably, the biomarkers were significantly associated with CD8 T cells and neutrophils. In addition, the drugs related to biomarkers were predicted, and ATOGEPANT with the molecular target (S100A12) had a high binding affinity (docking score = -10&#xa0;kcal/mol). CONCLUSION: AQP9, HLA-DQA1, MCEMP1, NKG7, and S100A12 were identified as biomarkers related to ARGs in AMI, which provides a new perspective to study the relationship between ARGs and AMI.

Humans↗
PubMed2002

Molecular methods for detection and quantification of myeloma cells after bone marrow transplantation: comparison between real-time quantitative and nested PCR.

Multiple myeloma is characterized by malignant plasma cell-infiltration of bone marrow. Treatment with high-dose therapy results in a high rate of clinical remissions, but almost all patients ultimately relapse. Clinical staging and detection of relapse are limited in sensitivity. Therefore, we established molecular methods based on the highly clone-specific CDR regions of the immunoglobulin VH locus for sensitive and specific detection of residual myeloma cells after bone marrow transplantation. VDJ rearrangements were identified using a set of VH primers and a JH primer. Clone-specific rearrangements were detected by comparison with germ-line sequences. With the nested PCR approach, first-round amplification with the consensus primers was done followed by second amplification with myeloma-specific primers. The real-time quantitative PCR was performed using a myeloma-specific forward primer in combination with a JH consensus TaqMan probe and reverse primer. Sensitivity was tested using dilutions of myeloma cell lines into mononuclear cells. Nested PCR had a sensitivity of 10(-6) and TaqMan PCR of 10(-4) to 10(-5). Specificity was determined by testing different cell lines and patients' probes. These results were confirmed by follow up of 2 patients after allogeneic transplantation with dose-reduced conditioning. Molecular methods are very sensitive and specific tools for follow up of myeloma patients after allogeneic transplantation. By using the quantitative approach, it is possible to see kinetics of bone marrow tumor load, which can be used to guide therapeutic decisions like donor leukocyte infusions (DLI).

Bone Marrow Transplantation↗
PubMed2026

Improvement the accuracy and reproducibility of telomere length measurement utilizing qPCR.

Telomere length serves as a well-established molecular biomarker for evaluating aging and age-associated diseases. Among various methods, quantitative PCR for telomere length detection is convenient, rapid, cost-effective, and capable of high-throughput analysis in large epidemiological cohorts. However, numerous studies have indicated that issues related to differences in DNA quality caused by DNA extraction process significantly affect the accuracy and reproducibility of qPCR-based telomere length quantification. Initially, we established a model of DNA integrity variation, by utilizing nucleic acid endonucleases of serial activity units to cleave genomic DNA, generating DNA with varying degrees of degradation. The integrity of DNA templates decreases, the reduction of long fragments and the increase of short fragments in the mixed telomere products are the causes of the disruption in Ct values. Moreover, compared with longer reference gene amplicons, the short-segment internal gene reference can reduce the impact of genomic integrity on its amplification. Subsequently, we utilized additional gel excision purification to reduce degradation products. It was found that gel excision processing provides the best stability for telomere length detection with the lowest coefficient of variation. Additionally, the introduce of another calibrator sample, which is used for to adjust the T/S value of the test sample, narrows the deviation between qPCR-derived telomere length and gold-standard Terminal Restriction Fragment (TRF) measurements. Collectively, these results reveal that gel excision purification supports stable telomere detection. Calculating the correction coefficient incorporating the short internal reference and calibrator minimizes measurement deviations relative to sample TRF values.

Telomere↗
PubMed2026

The COVID-19 pandemic influenced the temporal dynamics of antimicrobial resistance markers and bacterial community across urban wastewater treatment plants.

Urban wastewater systems represent important interfaces between human activity and the environmental occurrence of antimicrobial resistance (AMR) markers. We assessed the temporal dynamics of intI1, ermB, and the 16&#xa0;S rRNA gene by quantitative PCR across three wastewater systems (EPC, CJC, and JW) in Fortaleza, Brazil, from November 2021 to November 2023. Bacterial communities were additionally characterized by 16&#xa0;S rRNA gene metabarcoding in 18 samples collected in December 2021 and January 2022. A synchronized decline in 16&#xa0;S rRNA gene and intI1 concentrations beginning in late 2022 was observed across all three wastewater systems, suggesting a shift toward lower microbial abundance. The ermB gene showed higher and more variable concentrations during part of the pandemic period, followed by convergence toward lower levels; however, the absence of antimicrobial-consumption data precluded attribution of this pattern to changes in macrolide selective pressure. Normalized antimicrobial resistance marker abundances were comparatively stable at EPC and JW but more variable at CJC. EPC exhibited the highest ASV richness, whereas CJC and JW showed greater diversity according to Shannon and inverse Simpson indices. Beta-diversity analyses identified wastewater system as the principal factor associated with bacterial community structure, while the effect of sampling period was smaller and metric-dependent. Neither ermB nor intI1 was individually associated with community composition, although intI1 showed a limited effect after adjustment for wastewater system in one model. Physicochemical parameters were not significantly associated with normalized marker abundances in the exploratory paired analysis. Arcobacter, Acinetobacter, and other potentially relevant genera were detected, but no direct associations between these taxa and the monitored AMR markers could be established. These findings highlight the value of integrating longitudinal qPCR, microbiome profiling, and environmental characterization to improve the interpretation of targeted AMR markers in One Health wastewater surveillance.

Wastewater↗
PubMed2003

Tissue HHV6 and 7 determination in pediatric solid organ recipients--a pilot study.

Herpes virus infections remain a major challenge in solid organ transplantation. HHV6 and 7 blood viral load was associated with pathology after renal transplantation. Little is known about the significance of tissue HHV6 and 7 infections. A total of 18 tissue biopsies (13 kidney, three GI and two BAL) from nine pediatric transplant patients (five kidney, two liver, one combined liver and kidney and one bone marrow transplant) were subjected to blood HHV6 IgG and IgM testing. In addition, tissue HHV6 and 7 semi-quantitative PCR analysis with subsequent detection by ELISA and quantitative methods were applied to the same samples. We also studied four native kidney biopsies of children with other kidney disease. The results of the biopsies were correlated with clinical data. Of the transplant patients, 78% were HHV6 IgG positive. Six of nine had a positive IgM on at least one occasion, however, only two of nine transplant patients were symptomatic with a mixed CMV/EBV septic picture of multi-organ failure. Only these two patients had a significant tissue viral load for HHV6. Additionally, a very significant tissue viral load for HHV6 was detected in an immunocompromised patient 3 wk after a roseola-like febrile illness. The HHV6 copies were 31, 88 and 206 per 10 microL of DNA, respectively. In the patient who also had the fourth positive ELISA for HHV6 PCR product, the Multiplex PCR and restriction enzyme assay on its PCR product revealed a significant contribution by HHV7, while the HHV6-B signal was rather weak. Significant tissue HHV6 loads can be found in tissue biopsies from organ recipients with significant illness and also in native kidneys after primary infection. This may explain the high prevalence of HHV6 in transplanted kidneys. Further studies on HHV6 and 7 using molecular techniques should be supported.

Adolescent↗