Biomedical subjects

C A Thomas

Publications and source records attributed to C A Thomas.

At least 37 records · Page 2Linked to original sources

PubMed1998

The human oncoprotein MDM2 arrests the cell cycle: elimination of its cell-cycle-inhibitory function induces tumorigenesis.

The human oncoprotein MDM2 (hMDM2) overexpresses in various human tumors. If amplified, the mdm2 gene can enhance the tumorigenic potential of murine cells. Here, we present evidence to show that the full-length human or mouse MDM2 expressed from their respective cDNA can inhibit the G0/G1-S phase transition of NIH 3T3 and normal human diploid cells. The protein harbors more than one cell-cycle-inhibitory domain that does not overlap with the p53-interaction domain. Deletion mutants of hMDM2 that lack the cell-cycle-inhibitory domains can be stably expressed in NIH 3T3 cells, enhancing their tumorigenic potential. The tumorigenic domain of hMDM2 overlaps with the p53-interaction domain. Some tumor-derived cells, such as Saos-2, H1299 or U-2OS, are relatively insensitive to the growth-inhibitory effects of hMDM2. These observations suggest that hMDM2 overexpression in response to oncogenic stimuli would induce growth arrest in normal cells. Elimination or inactivation of the hMDM2-induced G0/G1 arrest may contribute to one of the steps of tumorigenesis.

3T3 Cells↗

PubMed1998

Short-term effects of early-acting and multilineage hematopoietic growth factors on the repair and proliferation of irradiated pure cord blood (CB) CD34+ hematopoietic progenitor cells.

PURPOSE: Hematopoietic growth factor(s) (GF) may exert positive effects in vitro or in vivo on the survival of hematopoietic stem and progenitor cells after accidental or therapeutic total body irradiation. METHODS AND MATERIALS: We studied the clonogenic survival and DNA repair of irradiated (0.36, 0.73, and 1.46 Gy) CD34+ cord blood (CB) cells after short-term incubation (24 h) with GFs. CD34+ cells were stimulated with basic fibroblast growth factor (bFGF), stem cell factor/c-kit ligand (SCF), interleukin-3 (IL-3), IL-6, leukemia inhibitory factor (LIF), and granulocyte-monocyte colony stimulating factor (GM-CSF) alone or in combination in short-term serum-free liquid suspension cultures (LSC) immediately after irradiation and then assayed for clonogenic progenitors. DNA repair was evaluated by analysis of DNA strand breaks using the comet assay. Survival of CFU-GM, BFU-E, and CFU-Mix was determined and dose-response curves were fitted to the data. RESULTS: The radiobiological parameters (D[0] and n) showed significant GF(s) effects. Combination of IL-3 with IL-6, SCF or GM-CSF resulted in best survival for CFU-GM BFU-E and CFU-Mix, respectively. Combinations of three or more GFs did not increase the survival of clonogenic CD34+ cells compared to optimal two-factor combinations. The D[0] values for CFU-GM, BFU-E, and CFU-Mix ranged between 0.56-1.15, 0.41-2.24, and 0.56-1.29 Gy, respectively. As for controls, the curves remained strictly exponential, i.e., all survival curves were strictly exponential without any shoulder (extrapolation numbers n=1 for all tested GF(s). DNA repair capacity of CD34+ cells determined by comet assay, was measured before, immediately after irradiation, as well as 30 and 120 min after irradiation at 1 Gy. Notably, after irradiation the 2-h repair of cytokine-stimulated and unstimulated CD34+ cells was similar. CONCLUSION: Our data indicate that increased survival of irradiated CB CD34+ cells after short-term GF treatment is mediated through proliferative GF effects on the surviving fraction but not through improved DNA repair capacity.

Cell Survival↗

PubMed1998

Generation of infectious retrovirus aerosol through medical laser irradiation.

A novel model system was used to investigate the spread of infectious particles and live cells through the application of lasers commonly used in clinical medicine. Supernatants from a cell line producing recombinant retroviruses carrying a marker gene (neoR) were exposed to Er:YAG-laser beams. Aerosols were collected from various sites and distances from the point of laser impact and were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) for neoR. In addition, a susceptible indicator cell line was used to investigate the presence of infectious virions in collected aerosols. To test the possibility of dissemination of viable cells, a cell line was laser irradiated, and the generated aerosols were analyzed for the presence of viable cells. The viral marker gene neoR could be detected in 16% (distance: 5.0-6.3 cm) to 59% (0.5-1.6 cm) of wells adjacent to the point of laser impact. The presence of infectious viruses in laser vapors conferring G418 resistance could be detected in 3% (distance 5.0-6.3 cm) to 20% (distance: 0.5-1.6 cm) of wells containing susceptible cells, and subsequent PCR analysis of isolated resistant clones revealed the presence of neoR-RNA and -DNA. Viable cells were detected in 40% (distance 0.7-3.6 cm) to 3% (distance 10.7-11.8 cm) of wells adjacent to the point of laser impact. These results demonstrate that laser vapors can contain infectious viruses, viral genes, or viable cells and may promote the spread of infections or tumor cell dissemination.

3T3 Cells↗

PubMed1998

Effect of cryopreservation of bovine sperm organelle function and viability as determined by flow cytometry.

Flow cytometry was used to compare the functional status of fluorescently stained sperm organelles from 12 Holstein bulls after storage for 24 h at 5 degrees C and after cryopreservation. The organelle-specific stains, SYBR-14 and LysoTracker Green DND-26, identified spermatozoa with intact plasmalemma and those with intact acrosomes, respectively. The mitochondria-specific stain, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyan ine iodide (JC-1), identified two populations of spermatozoa. One population stained red-orange because the JC-1 accumulated in the mitochondria as aggregates (characteristic of cells exhibiting a high membrane potential); a second population stained green because of JC-1 monomers within the mitochondria (characteristic of cells exhibiting a lower membrane potential). Analysis of variance revealed that within bulls, the properties of sperm viability, intact acrosomes, and mitochondrial status differed in spermatozoa stored for 24 h (p < 0.001) but not in cryopreserved spermatozoa (p > 0.11). Linear regression analyses resulted in significant models in which the proportions of stained spermatozoa stored for 24 h were indicative of those proportions observed in the cryopreserved fractions. These findings suggest that the plasmalemma, the acrosome, and the mitochondria of unfrozen spermatozoa varied as to their functional status. The cryopreservation process, however, resulted in a more uniform status of sperm organelles.

Animals↗

PubMed1998

Immunofluorescence microscopy and flow cytometry characterization of chemical induction of latent Epstein-Barr virus.

The effects of chemical induction of latent Epstein-Barr virus (EBV) with 12-O-tetradecanoyl phorbol-13-acetate (TPA) and n-butyrate on cell viability and induction of latent EBV in Raji and X50-7 B lymphocytes, indicated by expression of the diffuse component of the EBV early antigen (EA-D), were measured by visual immunofluorescence microscopy (of both viable and nonviable cells) and fluorescence-activated cell sorter (FACS) flow cytometry (of viable cells only). Cell viability at 4 days decreased moderately for treated Raji cells (9 to 37%, compared to 55 to 69% for untreated cells) and markedly for X50-7 cells (1-32% compared to 35-44% in untreated cells). The highest EA-D levels in viable cells occurred in Raji cells treated with both TPA and n-butyrate and untreated X50-7 cells. TPA and n-butyrate acted synergistically to induce latent EBV, resulting in increased levels of EA-D production in Raji cells and cell death in X50-7 cells. Methodological differences including the ability to detect antigen in only viable cells by FACS flow cytometry accounted for the higher levels of EA-D observed by FACS analysis compared to the levels observed by immunofluorescence microscopy. FACS analysis may be more objective and reproducible than immunofluorescence microscopy for the detection of EBV induction and also permits viral protein expression to be distinguished in the subpopulation of viable cells.

Antigens, Viral↗

PubMed1997

Human immunodeficiency virus-1 env impairs Fc receptor-mediated phagocytosis via a cyclic adenosine monophosphate-dependent mechanism.

Human immunodeficiency virus (HIV)-1 expression in mononuclear phagocytes is associated with multiple functional defects, including phagocytosis. To assess Fcgamma receptor (FcgammaR) function in cells expressing HIV-1, human promonocytic cells (U937) acutely or chronically infected with HIV-1, or stably transfected with a noninfectious reverse transcriptase (RT) defective HIV-1 provirus (Deltapol), were treated with phorbol 12-myristate 13-acetate for 48 hours and tested for their ability to ingest sheep erythrocytes coated with IgG (E-IgG). HIV-1-infected or transfected U937 cells ingested 50% to 65% fewer E-IgG than controls despite normal surface expression of FcgammaRs. HIV-1 specifically impaired FcgammaR-mediated phagocytosis, as ingestion of complement-coated erythrocytes was unaffected. U937 cells transfected with an env deficient mutant of HIV-1 ingested E-IgG normally, suggesting that the expression of HIV-1 env was required for HIV-1 to inhibit FcgammaR-mediated phagocytosis. Expression of HIV-1 in U937 cells was associated with an increased accumulation of intracellular cyclic adenosine monophosphate (cAMP); addition of the adenylate cyclase inhibitor 2',5'-dideoxyadenosine to these cells decreased intracellular cAMP levels to that of controls and restored FcgammaR-mediated phagocytosis. Addition of either interferon (IFN)-gamma or an inhibitor of cAMP-dependent protein kinase A (KT 5720) to HIV-1-transfected U937 cells also restored FcgammaR-mediated phagocytosis. Expression of HIV-1 induces a specific defect of FcgammaR function in mononuclear phagocytes that correlates with increased levels of cAMP, and can be corrected by pharmacologic manipulation.

Cyclic AMP↗

PubMed1997

Fluorometric assessments of acrosomal integrity and viability in cryopreserved bovine spermatozoa.

The combination of specific fluorometric staining and flow cytometry provides a rapid and precise means of assessing the functional status of cells. We sought to utilize this approach to quantify two important seminal characteristics, acrosomal integrity and sperm viability, and to compare these with classical microscopic measurements of acrosomal integrity and sperm motility. Samples of thawed, cryopreserved sperm packaged in 0.5-ml French straws were obtained from 12 Holstein bulls. Classical acrosomal assessments and sperm motility estimates were made using differential interference contrast microscopy. Fluorescent acrosomal probes included LysoTracker Green DND-26 (LYSO-G), fluorescein-labeled peanut agglutinin, the biotinylated isocoumarin serine protease inhibitor Bi-Aca-Aca-OMe-IC that was secondarily labeled with fluorescein-avidin, and rabbit antibodies to bovine acrosin that were secondarily labeled with fluoresceinated anti-rabbit immunoglobulin. The fluorescent probes for sperm viability were a combination of SYBR-14 and propidium iodide (PI) or of SYTO-17 and PI. Significant differences were found among methods and among bulls, but not among straws (n = 3). All four fluorescent measures of acrosomal integrity showed highly significant correlations with both classical measurements. These data indicated that the quality of cryopreserved bovine sperm samples could be readily quantified using a variety of organelle-specific fluorescent staining techniques.

Acrosin↗

PubMed1997

Fluorometric assessments of mitochondrial function and viability in cryopreserved bovine spermatozoa.

Mitochondrial function and sperm viability were quantified in samples of cryopreserved bovine spermatozoa from 12 bulls using fluorometric techniques. The active mitochondria of the spermatozoa were fluorescently stained using three different fluorophores: rhodamine 123 (R123), 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyan ine iodide (JC-1) or MitoTracker Green FM (MITO). The stained spermatozoa, and companion aliquots that had been stained with SYBR-14 (a living-cell nucleic acid stain) and propidium iodide to assess viability, were quantified using flow cytometry. The resulting fluorescent measurements of mitochondrial function were compared with microscopic assessments of progressive sperm motility immediately after thawing, with motility after 3-h incubation at 37 degrees C, and with the fluorescent assessment of sperm viability. Staining with either R123 or MITO resulted in a single green population. In contrast, the JC-1 staining of mitochondria produced both green and red-orange populations of spermatozoa and sometimes a progressive gradient between the two populations. The ability of JC-1 to discriminate between mitochondria exhibiting high membrane potential from those having low to medium membrane potential provided a more rigorous estimate of metabolic function than the other two fluorescent stains. Overall, the three fluorometric measurements of mitochondrial function were highly correlated with each other, with the SYBR-14 assessment of viability, and with the microscopic estimates of motility.

Animals↗

PubMed1997

Adoptive transfer of murine cytomegalovirus-immune lymph node cells prevents retinitis in T-cell-depleted mice.

PURPOSE: The purpose of this study was to determine whether adoptive transfer of murine cytomegalovirus (MCMV)-immune lymph node cells prevents retinitis in immunosuppressed mice. METHODS: Adult BALB/c mice were thymectomized and T-cell depleted using rat monoclonal antibodies specific for mouse CD4+ and CD8+ T-cells. The level of rat immunoglobulin G in the treated mice was monitored by enzyme-linked immunosorbent assay. Immune cells were labeled with PKH26-GH immediately before adoptive transfer, and flow cytometry was used to determine the percentage of adoptively transferred T-cells (PKH+, fluorescein isothiocyanate [FITC+]) in the spleens of the recipient mice 3 days after transfer. The ability of adoptively transferred cells to protect from retinitis was studied in T-cell-depleted mice injected with MCMV through the supraciliary route. Mice received 4 x 10(7) in vitro-restimulated MCMV-immune cells, 4 x 10(7) freshly isolated MCMV-immune cells, 4 x 10(7) freshly isolated ovalbumin-immune cells, or no cells (control group). RESULTS: The best time to balance depletion of endogenous T-cells with persistence of transferred cells was 3 weeks after T-cell depletion. Both restimulated and freshly isolated MCMV-immune cells conferred protection from retinitis. Freshly isolated ovalbumin-immune lymph node cells did not prevent retinitis, indicating that protection was virus-specific and merely was not because of transfer of antigen-activated lymph node cells. CONCLUSIONS: Adoptive immunotherapy has been used to prevent cytomegalovirus (CMV) infection in patients who have undergone transplantation, and, by extrapolation, the results of these studies suggest that adoptive immunotherapy with human CMV-specific immune cells might be used to prevent or ameliorate CMV retinitis in immunocompromised patients.

Animals↗

PubMed1996

Scavenger receptor-mediated adhesion of microglia to beta-amyloid fibrils.

A pathological hallmark of Alzheimer's disease is the senile plaque, containing beta-amyloid fibrils, microglia and astrocytes. Beta-amyloid fibrils exert a cytotoxic effect on neurons, and stimulate microglia to produce neurotoxins, such as reactive oxygen species. Mononuclear phagocytes, including microglia, express scavenger receptors that mediate endocytosis of oxidized low-density lipoproteins, and adhesion to glucose-modified extra-cellular matrix proteins. Here we report that class A scavenger receptors mediate adhesion of rodent microglia and human monocytes to beta-amyloid fibril-coated surfaces leading to secretion of reactive oxygen species and cell immobilization. Thus, class A scavenger receptors are potential therapeutic targets in Alzheimer's disease.

Alzheimer Disease↗

PubMed1996

Effects of two antiprogestins on early pregnancy in the long-tailed macaque (Macaca fascicularis).

The abortifacient effects of mifepristone and HRP 2000 were compared in gravid long-tailed macaques. Thirty-six animals were studied with treatment administered either by the oral (0.5 or 5.0 mg/kg; N = 5 per antiprogestin per dose) or intramuscular (i.m.) routes (0.5 mg/kg; N = 5 per antiprogestin) on gestational days (GD) 23-26; six vehicle controls were included. Blood samples were collected for assay of progesterone (P4) and each of the antiprogestins (pre-treatment, daily GD 23-28, every other day GD 30-40), and animals were monitored sonographically throughout gestation. Results of these studies indicated high rates of abortion with i.m. administration (3/5 mifepristone, 4/5 HRP 2000) and 5.0 mg/kg oral route (4/5, 2/5, respectively), with less effects noted at oral doses of 0.5 mg/kg (2/5, 0/5, respectively). No early abortions were observed in the control groups. Following daily i.m. treatment, peak levels of 8-16 ng/ml mifepristone were detected whereas 6-10 ng/ ml of HRP 2000 were noted (GD 26-27). No serum levels of mifepristone were detected following either of the oral doses whereas serum levels of 2-6 ng/ml HRP 2000 were noted with high dose oral administratation. Results of these studies suggest: (1) both antiprogestins are roughly comparable in terminating early pregnancy although HRP 2000 may be more efficacious when administered i.m. whereas mifepristone may be more effective when administered orally; (2) similar levels of biological activity are seen with the i.m. and high dose oral dosing regimens, with little or no activity with the oral low dose; and (3) infants resulting from surviving pregnancies were not affected by early gestation exposure.

Abortifacient Agents, Steroidal↗

PubMed1995

Interplay between mycoplasmas and host target cells.

The infectious pattern of mycoplasmas (Mycoplasma penetrans, Mycoplasma pneumoniae and Mycoplasma genitalium) in mammalian cells was examined using confocal microscopy and flow cytometry combined with cell fractionation and mycoplasma viability determinations. Within 2 h postinfection mycoplasmas parasitize cell surfaces, enter the intracellular spaces and locate throughout the cytoplasmic and perinuclear regions. These mycoplasmas can be cultivated from cytoplasmic and nuclear fractions 96 h later and continue to persist intracellularly for at least 7 days, suggesting a much more active intracellular role for mycoplasmas than had been considered previously.

Animals↗

PubMed1995

Role of the eosinophil in chronic vascular rejection of renal allografts.

Obiliterative arteriopathy in chronic renal allograft rejection is caused by intimal smooth muscle proliferation accompanied by infiltration of lymphocytes, monocytes, and eosinophils. We investigated the role of the eosinophil in chronic rejection. Twenty-four allograft nephrectomies were examined for the presence of eosinophils on hematoxylin-eosin-stained sections and using epifluorescence on Fisher-Giemsa-stained sections. Among 15 cases with chronic rejection, eosinophils were detected in 14 cases (93%) with epifluorescence compared with only six cases (40%) with hematoxylin-eosin staining (P = 0.005). With epifluorescence, eosinophils were identified in the intimal, adventitial, and tubulointerstitial compartments in 73%, 80%, and 87% of cases, respectively. To examine the pathogenic relevance of the eosinophils in the vessel wall, we investigated the effect of eosinophil-conditioned medium on DNA synthesis in cultured vascular smooth muscle cells. Autofluorescent eosinophils were isolated from atopic human donors using a fluorescence-activated cell sorter. Supernatant was collected from eosinophils (1 x 10(6)/mL) cultured overnight in medium with 0.5% fetal bovine serum. Incorporation of 3H-thymidine into DNA was measured in rat and human vascular smooth muscle cells treated for 24 hours with eosinophil-conditioned medium at 1:20, 1:10, 1:5, and 1:2 dilutions. Eosinophil-conditioned medium had a significant dose-dependent stimulatory effect on DNA synthesis in both cell lines. Our results indicate that eosinophil involvement in chronic renal allograft rejection is more common than previously recognized. The stimulatory effect of eosinophil-conditioned medium on vascular smooth muscle cell DNA synthesis suggests that eosinophils may be involved in the pathogenesis of the obliterative arteriopathy characteristically seen in chronic vascular rejection of renal allografts.

Animals↗

PubMed1995

Green fluorescent protein as a marker for gene expression and cell biology of mycobacterial interactions with macrophages.

The green fluorescent protein (GFP) of the jellyfish Aequorea victoria offers certain advantages over other bioluminescence systems because no exogenously added substrate or co-factors are necessary, and fluorescence can be elicited by irradiation with blue light without exposing the cells producing GFP to invasive treatments. A mycobacterial shuttle-plasmid vector carrying gfp cDNA was constructed and used to generate transcriptional fusions with promoters of interest and to examine their expression in Mycobacterium smegmatis and Mycobacterium bovis BCG grown in macrophages or on laboratory media. The promoters studied were: (i) ahpC from Mycoosis and Mycobacterium leprae, a gene encoding alkyl hydroperoxide reductase which, along with the divergently transcribed regulator oxyR, are homologues of corresponding stress-response systems in enteric bacteria and play a role in isoniazid sensitivity; (ii) mtrA, an M. tuberculosis response regulator belonging to the superfamily of bacterial two-component signal-transduction systems; (iii) hsp60, a previously characterized heat-shock gene from M. bovis; and (iv) tbprc3, a newly isolated promoter from M. tuberculosis. Expression of these promoters in mycobacteria was analysed using epifluorescence microscopy, laser scanning confocal microscopy, fluorescence spectroscopy, and flow cytometry. These approaches permitted assessment of fluorescence prior to and after macrophage infection, and analyses of promoter expression in individual mycobacteria and its distribution within populations of bacterial cells. Bacteria expressing GFP from a strong promoter could be separated by fluorescence-activated cell sorting from cells harbouring the vector used to construct the fusion. In addition, the stable expression of mtrA-gfp fusion in M. bovis BCG facilitated localization and isolation of phagocytic vesicles containing mycobacteria. The experiments presented here suggest that GFP will be a useful tool for analysis of mycobacterial gene expression and a convenient cell biology marker to study mycobacterial interactions with macrophages.

Animals↗

PubMed1995

Difficulties encountered in identification of a nutritionally deficient streptococcus on the basis of its failure to revert to streptococcal morphology.

Difficulties were encountered in the recognition of a nutritionally deficient streptococcus which continued to display aberrant morphologic forms (especially bulbous swellings and filament formation) despite provision of growth factors. With isolates displaying diverse morphologic entities not characteristic of a given species, e.g., Streptobacillus moniliformis or Erysipelothrix rhusiopathiae, nutritionally deficient streptococci should be considered.

Bacteremia↗

PubMed1994

TAT-mediated transcellular activation of HIV-1 long terminal repeat directed gene expression by HIV-1-infected peripheral blood mononuclear cells.

We have previously shown evidence of Tat-mediated transcellular activation of the HIV-1 long terminal repeat (LTR) in vitro by using a laboratory-adapted strain of HIV-1. To examine the biologic significance of this observation, we asked whether primary PBMCs from HIV-1-infected individuals will transactivate the HIV-1 LTR transcellularly in suitable indicator cells. In cultures of PBMCs isolated from HIV-1-infected patients at various clinical stages, with either HIV-1 LTR-transfected Jurkat T cells or nonfusigenic HIV-1 LTR-transfected murine fibroblasts, transcellular activation was readily detected. Transactivation of the LTR in cocultured cells with HIV-1-infected PBMCs is detectable 1 to 2 wk before the onset of significant virus production and at ratios as low as 1 infected cell to 10(6) surrounding cells. Addition of the Tat inhibitor RO5-3335 substantially decreases transcellular activation, even at low concentrations (0.01 microM) that do not affect virus levels. In contrast, addition of the antiretroviral agent zidovudine has no effect on transcellular activation. These data suggest that Tat-mediated transcellular activation of the HIV-1 LTR occurs independently of cellular infection, and provides a mechanism that can promote the spread of HIV-1 in susceptible cell populations.

Cells, Cultured↗

PubMed1994

Macrophages adhere to glucose-modified basement membrane collagen IV via their scavenger receptors.

Scavenger receptors have been reported to mediate macrophage adhesion to serum-coated plastic surfaces. We report here that scavenger receptors promote the divalent cation independent adhesion of human monocytes and macrophages to surfaces coated with non-enzymatically glycated collagen IV but not to surfaces coated with native collagen IV. Ligands for scavenger receptor types I and II blocked adhesion of monocytes and macrophages to non-enzymatically glycated collagen IV but had no effect on adhesion of these cells to albumin-coated surfaces. U937 human promonocyte-like cells transfected with cDNA encoding bovine scavenger receptor I or II adhered to surfaces coated with glycated-collagen IV but not to surfaces coated with native collagen IV. A synthetic peptide homologous to the domain of bovine scavenger receptor that binds modified low density lipoproteins (residues 327-343) inhibited the adhesion of U937 cells transfected with cDNA encoding bovine scavenger receptor II to glycated collagen IV, whereas a control peptide from the alpha helical domain of scavenger receptor II (residues 121-137) had no effect on adhesion of these cells. Macrophages plated on surfaces coated with glycated collagen IV were unable to endocytose acetylated low density lipoproteins from the medium, suggesting that their scavenger receptors were occupied in binding these cells to the substrate. These findings suggest new roles for scavenger receptors in the accelerated development of vascular lesions observed in diabetics.

Amino Acid Sequence↗

PubMed1994

Clinical application of polymerase chain reaction amplification to diagnosis of herpes virus infection.

Amplification of viral DNA offers a potentially sensitive and specific method for identifying herpes viruses in pathologic specimens. The purpose of this study is to assess the value of polymerase chain reaction amplification of DNA as a diagnostic test for herpes virus in pathologic specimens. The purpose of this study is to assess for herpes virus infections. We examined 79 paraffin-embedded tissue samples from 43 patients and 55 viral culture samples from 45 patients. Herpes virus DNA in the specimens was amplified by polymerase chain reaction. Using paraffin-embedded tissue on which a diagnosis of herpes virus was made by morphologic criteria, 11 of 19 patients had herpes virus DNA identified by PCR; herpes virus DNA was not identified in any of 35 negative control specimens. Herpes virus DNA was also identified by polymerase chain reaction in all of the positive herpes virus culture specimens. Of 29 culture negative specimens, herpes virus DNA was identified in six. We conclude that polymerase chain reaction is useful to establish or confirm the presence of a herpes virus infection in paraffin-embedded tissue samples and that it is more sensitive than viral culture.

DNA, Viral↗