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C A Gleaves

Publications and source records attributed to C A Gleaves.

At least 37 records · Page 2Linked to original sources

Rapid detection of cytomegalovirus in bronchoalveolar lavage specimens from marrow transplant patients: evaluation of a direct fluorescein-conjugated monoclonal antibody reagent.

An FITC-conjugated monoclonal antibody reagent containing three CMV-specific monoclonal antibodies was evaluated for the rapid detection of CMV in bronchoalveolar lavage (BAL) cytospin preparations by direct IF (DFA). Eighty-six BAL samples from 72 marrow transplant patients were inoculated into both centrifugation and standard cell culture. CMV was detected in 49/86 (57%) BAL samples. DFA detected 37/46 (80%) samples which were positive in centrifugation culture. While DFA staining lacked the sensitivity (overall sensitivity 38/49, 78%) to replace either standard or centrifugation culture, the total laboratory time needed to complete the DFA was only 1.5 h and its concurrent use with centrifugation culture can provide rapid specific diagnosis of CMV pneumonia.

Antibodies, Monoclonal↗

Detection of cytomegalovirus from clinical specimens in centrifugation culture by in situ DNA hybridization and monoclonal antibody staining.

An in situ DNA hybridization kit for cytomegalovirus (CMV) was evaluated for the detection of CMV in centrifugation culture. Of 61 clinical specimens, 17 (27.8%) were positive for CMV by monoclonal antibody staining following centrifugation. Of the 17 positive specimens, 15 were detected by DNA hybridization (24.5%). However, the earliest that CMV could be detected by DNA hybridization was 58 h as compared with 16 h with monoclonal antibodies following centrifugation. DNA hybridization remains of great interest for the study and detection of CMV infection. However, current DNA hybridization techniques are not sufficiently rapid to replace the use of monoclonal antibodies in centrifugation culture.

Antibodies, Monoclonal↗

Direct detection of cytomegalovirus from bronchoalveolar lavage samples by using a rapid in situ DNA hybridization assay.

An in situ DNA hybridization assay was compared with centrifugation culture for rapid detection of cytomegalovirus (CMV) from bronchoalveolar lavage (BAL) samples. Eighty BAL samples were inoculated into both centrifugation culture and standard culture. Cytospin preparations of the BAL samples were studied in a 75-min in situ DNA hybridization assay using the PathoGene CMV kit (Enzo Biochem, Inc., New York, N.Y.). Of the 80 samples, 39 (49%) were positive for CMV; 37 of 39 (95%) were positive by centrifugation culture, 34 of 39 (87%) were positive in standard culture, 24 of 39 (62%) were positive by in situ hybridization, and 20 of 39 (56%) were positive by histologic and/or immunofluorescence techniques. The in situ hybridization assay detected 23 of the 37 samples positive in centrifugation culture, for a sensitivity of 62% and a specificity of 98%. We conclude that the in situ hybridization assay is a specific and more rapid test than centrifugation culture and standard culture for diagnosis of CMV pulmonary infection. For the clinical laboratory, however, current hybridization methods are not sufficiently sensitive to replace centrifugation culture for detection of CMV in BAL specimens.

Bronchoalveolar Lavage Fluid↗

Evaluation of a latex particle agglutination assay for the detection of cytomegalovirus antibody in patient serum.

The Virogen CMV Antibody Test is a simple and rapid latex agglutination assay for the detection of cytomegalovirus antibody in human serum and plasma. Evaluation of this assay with respect to enzyme immunoassay yielded a sensitivity of 98% with a specificity of 100%. In comparison to CMVScan, the Virogen CMV Antibody Test had a sensitivity of 98.4% and a specificity of 100%.

Antibodies, Viral↗

Multisite evaluation of a monoclonal antibody reagent (Syva) for rapid diagnosis of cytomegalovirus in the shell vial assay.

A pre-cytopathic effect (CPE) monoclonal antibody reagent (Syva Co., Palo Alto, Calif.) was evaluated in four laboratories for the rapid detection of cytomegalovirus (CMV) in shell vial cell cultures at 16 to 24 h and 40 to 48 h postinoculation. Results were compared with those obtained by inoculation of the specimen into conventional tube cell cultures that were examined for the presence of typical CMV CPE and subsequently tested by reaction with the monoclonal antibody reagent in an indirect immunofluorescence test. Of 937 specimens, CMV was positive in 184 (20%). CMV was detected twice as frequently in shell vials only (n = 29) as in conventional tube cell cultures (n = 14). Pre-CPE shell vial assay was 91% sensitive (range, 84 to 98%) and 96% specific (range, 93 to 98%) compared with the detection of CPE in conventional tube cell cultures. Overall, 137 of 166 (83%) and 143 of 166 (86%) of the CMV strains were detected at 16 to 24 h and 40 to 48 h postinoculation, respectively. The Syva reagent produced sensitive and specific results for the rapid detection of CMV infection in shell vial cell cultures and reliably confirmed the presence of the virus as detected by CPE in conventional tube cell cultures.

Antibodies, Monoclonal↗

Detection of herpes simplex virus by using A549 cells in centrifugation culture with a rapid membrane enzyme immunoassay.

The RAMP herpes simplex virus (HSV) culture confirmation test was compared with immunofluorescence (IF) staining with a specific HSV monoclonal antibody reagent for the detection of HSV in centrifugation culture. The RAMP test detected 47 of 57 IF-positive specimens (sensitivity, 88.6%) and agreed with 217 of 220 IF-negative specimens (specificity, 98.6%). The RAMP test can be performed in less than 15 min and gives an immediate visual result. However, the sensitivity and the false-positive and false-negative results need further investigation.

Cell Line↗

Respiratory virus infection in immunocompromised patients.

Seventy-eight immunocompromised patients were prospectively evaluated for infection with respiratory viruses including parainfluenza viruses, respiratory syncytial virus, influenza viruses and adenoviruses beginning before marrow transplant and continuing to 60 days after transplant or discharge from hospital. Patients were studied both on a fixed surveillance schedule and at any time upper or lower respiratory symptoms developed. Fifteen (19%) patients had a respiratory virus detected including parainfluenza 1 in six patients, adenovirus in five, parainfluenza 3 in two, and influenza A and respiratory syncytial virus in one each. Twelve patients had infection before transplant and 11 of these had upper respiratory symptoms. Three patients had virus isolated only after transplant. Both patients with parainfluenza 3 infection developed pneumonia. One patient died with disseminated adenovirus infection. These data suggest that infections with respiratory viruses are frequent and often symptomatic in immunocompromised patients. Since antiviral therapy is available for some of these infections, early specific viral diagnosis is of potential clinical importance in immunocompromised patients with respiratory symptoms.

Adolescent↗

Determination of patient herpes simplex virus immune status by latex agglutination.

A rapid latex agglutination (LA) test was compared with complement fixation and enzyme immunoassay for the determination of herpes simplex virus immune status in sera of patients. Of 173 samples, 88% gave concordant results in all three assays (115 positive and 37 negative). The LA and complement fixation tests agreed 92% of the time, and the LA agreed with the enzyme immunoassay 94% of the time. LA is a simple and rapid test which can be used for determining the herpes simplex virus immune status in sera of patients.

Antibodies, Viral↗

Use of murine monoclonal antibodies for laboratory diagnosis of varicella-zoster virus infection.

The laboratory diagnosis of varicella-zoster virus (VZV) infection was reevaluated by direct immunofluorescent-antibody staining (DFA) and centrifugation culture with newly available murine monoclonal antibodies. Specimen smears were examined by DFA using monoclonal antibodies to VZV and to herpes simplex virus types 1 and 2. Specimens were also inoculated into shell vials for centrifugation culture and into standard tube cell culture. Of 68 specimens tested from 60 patients, 39 (57%) were positive for VZV by at least one method. DFA was positive in 36 of 39 (92%); centrifugation culture was positive at 24 h in 23 of 39 (59%) and at 48 h in 31 of 39 (79%); and standard culture was positive in 25 of 39 (64%). Twenty-three of the 39 positive specimens (59%) were positive by all three techniques. Forty-three of the 60 patients were considered to have VZV by clinical criteria, and 35 of these 43 (81%) had laboratory confirmation of the diagnosis. These data confirm that DFA is the method of choice for the rapid laboratory confirmation of VZV infection. The centrifugation culture assay can provide an alternative method to DFA for the laboratory diagnosis of VZV infection.

Animals↗

Rapid detection of cytomegalovirus pulmonary infection by bronchoalveolar lavage and centrifugation culture.

Cytomegalovirus infection remains a major cause of morbidity and mortality in marrow transplant recipients. Results of a rapid centrifugation viral culture of bronchoalveolar lavage specimens from 33 marrow transplant recipients with pneumonia were compared with those for conventional viral culture of concurrently or subsequently obtained lung tissue. The centrifugation culture results were also compared to results of cytologic and immunochemical examination of these specimens. Centrifugation culture was positive within 16 hours of inoculation in 22 of 23 (96%) specimens from patients with positive conventional culture of lung tissue. Detection of cells positive for cytomegalovirus by immunofluorescent antibody staining or cytologic identification was less sensitive (59% and 29%, respectively). There was no evidence of cytomegalovirus in specimens from patients without evidence of cytomegalovirus pulmonary infection by any technique. The sensitivity (96%) and specificity (100%) of centrifugation culture of specimens from marrow transplant recipients approach that of viral culture of lung tissue.

Adolescent↗

Comparison of MRC-5 and HFF cells for the identification of cytomegalovirus in centrifugation culture.

Detection of cytomegalovirus (CMV) by centrifugation culture was compared in MRC-5 and HFF cells. At 24 hr 47 of 130 specimens (36%) were positive for CMV, 45 in MRC-5, and 35 in HFF cells. At 48 hr 45 specimens were positive in both MRC-5 and HFF cells. MRC-5 cells appear to be superior for the detection of CMV at 24 hr in centrifugation culture; however, both lines are comparable at 48 hr.

Cell Line↗

Rapid diagnosis of invasive cytomegalovirus infection by examination of tissue specimens in centrifugation culture.

Two hundred eight tissue specimens from 81 patients were examined by centrifugation culture for the rapid diagnosis of invasive cytomegalovirus (CMV) infection. Results were compared with those obtained by both conventional viral cultures and histologic examination. CMV was identified by centrifugation culture in 52 (25%) specimens at 16 hours after inoculation, including 39 lung specimens and 12 gastrointestinal specimens. One additional esophageal specimen was positive (53 of 208 specimens; 25.5%) at 36 hours. In contrast, CMV was recovered from only 50 of these 53 specimens by conventional cell culture at a mean of 11 days after inoculation. Forty-three of the 208 specimens (20.5%) were positive for CMV when examined by histologic methods, including light microscopy and tissue immunofluorescence. All 43 were positive by centrifugation culture. Specimens that were positive by centrifugation culture but negative by histologic methods included three lung specimens and seven gastrointestinal specimens. The technic of centrifugation culture is more sensitive for diagnosis of invasive CMV infection by the examination of affected tissue than either conventional viral culture or histologic technics, including tissue immunofluorescence, and more rapid than conventional culture or routine histologic examination.

Antibodies, Monoclonal↗

Improved DNA hybridization method for detection of acyclovir-resistant herpes simplex virus.

A simplified DNA hybridization method was developed to detect acyclovir-resistant isolates of herpes simplex virus. Herpes simplex virus-infected cell cultures in microtiter plates were treated with concentrations of acyclovir ranging from 8 to 0.015 micrograms/ml. At 48 h postinfection, infected cells were lysed by a one-step procedure and lysates were absorbed to membranes. Without further treatment, membranes were hybridized by using a herpes simplex virus-specific radioiodinated probe. The membranes were then washed and counted in a gamma counter. The elapsed time for assay performance was 4 h. Parallel plaque reduction assays were performed for comparison. The mean 50% inhibitory dose of in vivo- and in vitro-derived acyclovir-resistant, thymidine kinase-negative isolates was greater than 2 micrograms/ml by DNA hybridization. The 50% inhibitory dose of acyclovir-susceptible, thymidine kinase-positive isolates ranged from 0.01 to 1.1 micrograms/ml. This assay is simple and objective and should facilitate antiviral susceptibility testing in diagnostic laboratories.

Acyclovir↗

Evaluation of a direct fluorescein-conjugated monoclonal antibody for detection of cytomegalovirus in centrifugation culture.

A fluorescein-conjugated murine monoclonal antibody (MAb) reactive with cytomegalovirus (CMV) was evaluated for the detection of CMV in centrifugation culture. Of 188 specimens, 90 were positive for CMV in centrifugation culture. The fluorescein-conjugated MAb detected CMV in 86 of 90 (95%) specimens at 16 h postinoculation, and 88 of 90 (98%) were positive at 36 h. The fluorescein-conjugated MAb can be used in a direct immunofluorescence assay that can be completed in 15 min following cover slip fixation. Use of this antibody in centrifugation culture provides a convenient and rapid assay for the identification of CMV.

Antibodies, Monoclonal↗

Comparison of culture, cytotoxicity assays, and enzyme-linked immunosorbent assay for toxin A and toxin B in the diagnosis of Clostridium difficile-related enteric disease.

Clostridium difficile culture, test tube, and microtiter cytotoxicity assays, and enzyme-linked immunosorbent assays (ELISAs) for toxin A and toxin B, were simultaneously performed on 113 fresh diarrheal stool specimens randomly selected from those submitted to our clinical laboratory for routine C. difficile testing. The performance of these tests in diagnosing C. difficile-related enteric disease (CDRED) was based on a clinical assessment of the likelihood of CDRED as determined by a systematic review of case histories blinded from the test results. Among 61 antibiotic recipients, both the microtiter cytotoxicity assay and the toxin A ELISA were highly specific for CDRED (95% and 100%, respectively). Specificities for the other procedures were much lower (tube cytotoxicity assay, 79%; culture, 74%; and toxin B ELISA, 56%). The high sensitivities of the culture (89%) and toxin B ELISA (83%) were somewhat negated by their low specificities. The only test that was both specific and had acceptable sensitivity (78%) was the microtiter cytotoxicity assay. This study indicates that ELISAs for detection of C. difficile toxins are not as reliable as the cytotoxicity assay in the laboratory diagnosis of CDRED, and that clinical correlation is essential in the evaluation of any new test for CDRED.

Adult↗

Monoclonal antibody for rapid laboratory detection of cytomegalovirus infections: characterization and diagnostic application.

Monoclonal antibodies to early (2H2.4, molecular weight 72,000 daltons) and late (2F3.0, molecular weight 68,000 daltons) antigens of the AD-169 strain of cytomegalovirus (CMV) were prepared by fusing mouse spleen cells with NS-1 mouse myeloma cells. The 2H2.4 monoclonal antibody produced a dense immunofluorescence with prominent lobular staining within the nucleus of CMV-infected substrate cells, whereas the reaction of 2F3.0 was more diffuse and generally involved the entire nucleus of the cells. Both monoclonal antibodies had little or no neutralizing activity against CMV in plaque-reduction assays. No cross-reactions were observed between these monoclonal antibodies and other members of the herpesvirus group. The 2H2.4 monoclonal antibody to early CMV antigen was used in a shell vial assay with a low-speed centrifugation step for the rapid (within 16 hours after inoculation) diagnosis of CMV infections. Optimal conditions for the test included centrifugation of shell vials at 700 X g for 45 minutes at 36 degrees C. An inoculum volume of 0.2 ml provided a reasonable balance between the optimal sensitivity for detecting specific viral fluorescence and the easy discrimination of the specific immunofluorescence from the background debris. Because of the commercial availability of the monoclonal antibody and the simplicity of the procedures used in the shell vial assay and subsequent fluorescence techniques, this rapid assay can be done in any laboratory that is familiar with cell culture manipulations.

Animals↗

Detection of viral and chlamydial antigens in open-lung biopsy specimens.

The recovery of viruses and Chlamydia trachomatis from cell cultures and the detection of their antigens in impression smears prepared from open-lung biopsy (OLB) specimens from immunocompromised adults were compared. Touch impression smears were prepared on three slides, each containing eight wells. OLB tissue was homogenized (Stomacher) and inoculated into MRC-5, primary monkey kidney, and McCoy cell cultures. The direct and indirect immunofluorescence (IF) tests were used to detect antigens to the following organisms: herpes simplex virus, adenovirus, parainfluenza types 1 and 3, respiratory syncytial virus, cytomegalovirus (CMV), Chlamydia trachomatis, influenza types A and B, and varicella-zoster virus. Of 105 OLB specimens, 21 viral isolates (20%) were recovered in cell culture; 20 were CMV and one was an influenza virus type A (H3N2). Both culture and IF results were positive with 12 specimens, but in nine instances a virus was isolated and IF was negative or eight times culture results did not yield the organism but IF test results were positive. Chlamydia trachomatis was never isolated or detected by IF. The authors recommend that for optimal detection of CMV from OLB specimens a new rapid centrifugation-enhanced cell culture system be used in preference, or in conjunction with a preliminary IF screen of impression smears for CMV detection.

Adult↗