Cytomegalovirus DNA level on biopsy specimens during treatment of cytomegalovirus gastrointestinal disease

BACKGROUND & AIMS

There is no clear and point for the response to treatment of gastrointestinal human cytomegalovirus (HCMV) disease. HCMV-DNA quantitation on gastrointestinal biopsy specimens has proven its value for the diagnosis of gastrointestinal HCMV disease in patients with acquired immunodeficiency syndrome (AIDS). The aim was to study HCMV-DNA levels on gastrointestinal biopsy specimens during the treatment of gastrointestinal HCMV disease.

METHODS

HCMV-DATA quantitation was performed using two different polymerase chain reaction assays on 90 biopsy specimens obtained before anti-HCMV therapy, during the induction phase, or during maintenance therapy for gastrointestinal HCMV disease in 21 patients with AIDS.

RESULTS

HCMV-DNA was detected on all the biopsy specimens ranging from 9 to > or = 80,000 Eq/0.1 microgram DNA. Pretherapeutic mean level was 69,000 +/- 27,000 Eq/0.1 microgram DNA. Induction therapy was followed by a mean decrease of 1.7 +/- 1.3 log10 Eq/0.1 microgram DNA. HCMV-DNA levels decreased during induction therapy to < 1000 Eq/0.1 microgram DNA in 60% of patients but remained > 80,000 Eq/0.1 microgram DNA in 20% of patients. Relapse occurred in all the patients in a mean time of 100 days. HCMV-DNA level at the end of the induction phase seems to influence the time to relapse.

CONCLUSIONS

Quantitation of HCMV-DNA on gastrointestinal biopsy specimens seems to be useful for monitoring gastrointestinal HCMV disease in patients with AIDS.

Monitoring levels of human cytomegalovirus DNA in blood after liver transplantation

We evaluated a semiquantitative PCR assay prospectively in 40 liver transplant recipients as an aid in making a prompt diagnosis of cytomegalovirus (CMV) infection. For 2 months after transplantation, clinical specimens from patients were tested weekly by PCR, virus isolation from peripheral blood and urine, and CMV serology. The incidence of active CMV infection was 70%. The levels of CMV DNA determined by hybridization of PCR samples and densitometric scanning of blots were assigned a score of 1 to 4 by comparison with four external standards amplified in parallel and corresponding to a range of 80 to 80,000 genomes. The first detection of CMV in blood by PCR occurred at a mean of 15 days, and high-level PCR scores of 3 or 4 were obtained 21 days after transplantation, whereas viremia occurred 33 days after transplantation. Significantly higher levels of CMV DNA were seen in patients with CMV disease (P < 0.05) than in asymptomatic patients. The prevalence of symptomatic CMV infection was 30%. The positive predictive value of PCR was 48%, while the negative predictive value was 100%. After treatment, the clearance of CMV DNA was always observed and the disappearance of symptoms occurred concomitantly with undetectable PCR signals.

Polymerase chain reaction detection of human cytomegalovirus in over 2000 blood specimens correlated with virus isolation and related to urinary virus excretion

The polymerase chain reaction (PCR) as applied to human cytomegalovirus (HCMV) detection should provide a valuable tool for rapid, reliable diagnosis of infection, thereby allowing prompt treatment. However, to date the high sensitivity of this technique and the lack of semi-quantitative interpretation have hindered establishing its validity for diagnosing systemic infection. We describe a rapid, simple, semi-quantitative PCR technique for HCMV detection. The validity of the technique was tested objectively by analyzing over 2000 leukocytes specimens by PCR and comparing the results with virus isolation from urine and blood in concomitant samples in the absence of any clinical data. It could thus be established that this technique had a sensitivity and specificity of 97%. When the PCR signal corresponded to > or = 8000 genome equivalents for 10(4) leukocytes, the predictive value for viremia was 86%. This semi-quantitative PCR technique should allow rapid diagnosis of systemic infection and provide a reliable means of monitoring clearance of CMV from blood during drug therapy.

Demonstration of Epstein-Barr virus replication in Reed-Sternberg cells of Hodgkin's disease

Epstein-Barr virus (EBV) is detectable in approximately 40% of cases of Hodgkin's disease (HD). The viral genomes remain latent but positive staining with anti-ZEBRA antibody in a small fraction of Reed-Sternberg (RS) cells of some cases of HD would suggest possible activation of EBV replication within these cells. We report the investigation of 40 cases of EBV-associated HD (including 5 human immunodeficiency virus [HIV]-positive cases) using anti-ZEBRA antibodies. Positive staining was found in only three (HIV-negative) cases. One of these three cases showed approximately 1% of ZEBRA-positive tumor cells, whereas the other two cases showed rare positive cells. In the case with 1% ZEBRA-positive cells, a strong signal was obtained with anti-EA-R antibody and BHLF1 oligoprobes, which indicated early gene expression. EBV replication could be shown in this case by nonisotopic in situ DNA-DNA hybridization, which showed markedly increased numbers of EBV genomes in a few RS cells. Viral replication was confirmed using reverse transcriptase and polymerase chain reaction that detected transcripts from the BLLF1 gene encoding for the membrane antigen gp350/220. EBV replication in RS cells seems to be an exceptional event but may provide clues to mechanisms of control of viral latency and assume clinical implications in the future.

Polymerase chain reaction detection of cytomegalovirus DNA in peripheral blood leukocytes as a predictor of cytomegalovirus disease in HIV-infected patients

OBJECTIVE

To describe and evaluate a polymerase chain reaction (PCR) method for early diagnosis and prompt management of cytomegalovirus (CMV) retinitis in HIV-infected patients.

METHODS

A total of 110 HIV-infected patients (Centers for Disease Control and Prevention stages II to IV) were sampled sequentially for isolation of CMV from peripheral blood leukocytes (PBL; n = 560) and for amplification of CMV DNA in PBL. Semiquantitative analysis of the PCR product was performed and each PCR-positive specimen was assigned a score between 1+ and 4+ (corresponding to four points on a standard curve of dilutions: 80, 800, 8000 and 80,000 CMV genome copies).

RESULTS

Levels of CMV DNA in blood increased with HIV infection stage. We focused on eight patients who developed one or more episodes of retinitis during longitudinal follow-up, in whom we found a strong correlation between viraemia, high PCR signal (3+ or 4+) (P < 0.0001) and clinical symptoms. Relapse was preceded by an increase in CMV DNA and resolution correlated with clearance of CMV DNA from blood.

CONCLUSIONS

Persistent high PCR levels always preceded virus isolation and may be the first indication of organ involvement and thus early treatment. PCR scores were consistently useful as indicators of drug efficacy and for monitoring of treatment.

The DNA-binding domain of two bZIP transcription factors, the Epstein-Barr virus switch gene product EB1 and Jun, is a bipartite nuclear targeting sequence

The Epstein-Barr virus BZLF1 gene product EB1 (also called ZEBRA and Zta), is a transcription factor belonging to the bZIP (basic domain leucine zipper) family of nuclear proteins. Translocation to the nucleus of EB1 (J. Becker, U. Leser, M. Marschall, A. Langford, W. Jilg, H. Gelderblom, P. Reichart, and H. Wolf, Proc. Natl. Acad. Sci. USA 88:8332-8336, 1991) and of two other bZIP proteins, c-Jun and c-Fos (P. Roux, J.-M. Blanchard, A. Fernandez, N. Lamb, P. Jeanteur, and M. Piechaczyk, Cell 63:341-351, 1990), has been shown to be subject to regulation. We show here that for both EB1 and Jun the nuclear targeting signals (NTS) in the proteins' primary sequences are two clusters of positively charged amino acids. These clusters, called BRA and BRB, are necessary and sufficient to direct beta-galactosidase to the nuclear compartment and act as a bipartite NTS. They are conserved among all the bZIP proteins, and although they are not identical, they probably share the same function. Site-directed mutagenesis studies made on these basic clusters suggest that they also act as a bipartite NTS in the EB1 protein. Our results also demonstrate that in EB1 and Jun, these bipartite NTS are superimposed with bipartite DNA-binding domains, since BRA and BRB are required in vitro for direct and specific contact between these proteins and their DNA-binding sites.

Specific detection of monocytic lysozyme within normal and leukemic cells

A murine monoclonal antibody against human lysozyme (AHL MoAb) was produced and tested on normal and leukemic monocytes using flow cytometry. The antibody gave a positive reactivity on normal monocytes permeabilized by saponin (82% to 98% of positive cells) and a negative reactivity on normal permeabilized neutrophils. This monocyte-specific reactivity had not been observed using a polyclonal antibody. Nevertheless, immunoblotting detected lysozyme in both monocyte and polymorphonuclear leukocyte (PMNL) lysates. The AHL MoAb, in the presence of lysozyme substrate (Micrococcus lysodeikticus cell walls), strongly inhibited the enzymatic activity. Flow cytometric analysis of leukemic cells isolated from patients suffering from different subtypes of acute myeloid leukemia (French-American-British [FAB] classification FAB M1-5) showed a highly significant positivity of FAB M5 for lysozyme compared with the other subtypes. The present results were consistent with the detection of a lysozyme epitope by AHL MoAb located near the catalytic site in monocytes. The same epitope was probably masked in PMNL granules.

Freeze-dried erythrocytes for an indirect hemagglutination test for detection of cytomegalovirus antibodies

An indirect hemagglutination test with lyophilized, fixed, tanned, and cytomegalovirus (CMV)-sensitized sheep erythrocytes for the detection of CMV antibodies is reported. To avoid nonspecific hemagglutination, cells were fixed with glutaraldehyde or Formalin directly in whole blood. The lyophilized, CMV-sensitized erythrocytes obtained by this technique were stable up to 9 months at 37 degrees C and retained the same reactivity at fresh, CMV-sensitized cells. Indirect hemagglutination performed with lyophilized, sensitized cells was highly efficient in detecting CMV-antibodies as compared with complement fixation and enzyme immunoassay.