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We used polymerase chain reaction (PCR) to detect cytomegalovirus (CMV) deoxyribonucleic acid (DNA) in the bronchoalveolar lavages (BAL) of 16 CMV-infected patients with active disease. We also tested PCR on a control group of 20 patients including latently infected patients without evidence of active CMV infection. Results were compared with those of CMV culture and of a rapid method of diagnosis which detects CMV in BAL cells by nucleic acid hybridization. PCR allowed the diagnosis in 93% of the actively infected patients compared to 73% for the CMV culture. Among the 20 control patients without evidence of active CMV infection, PCR was negative in all the 24 BAL tested. Hybridization on BAL cells with the CMV probe detected nine out of 10 actively infected patients, but the specificity of the test was only 68.5%. In our experience, PCR appears to be at least as sensitive as CMV culture, it provides results faster and it performs better than the detection of the virus by hybridization on BAL cells. Only active CMV infection was detected with the PCR conditions used in our study. This suggests that the PCR can be applied to bronchoalveolar lavage fluids as a rapid method to detect CMV lung infection.

By cDNA mutagenesis, we have constructed internal and C-terminal deletions (delta 21-51, delta 52-97, delta 97-104, delta 127-174, delta 97-184 and delta 134-184) in human interleukin-6 (hIL-6). All those deletion-carrying hIL-6 (delta hIL-6) proteins were then produced in Xenopus laevis oocytes and examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results show that, at least in frog oocytes, the first potential N-glycosylation site (Asn45) is utilized exclusively. The IL-6 conformation of these deletion-carrying proteins has been studied by immunoprecipitation with two kinds of monoclonal antibodies (mAb's): mAb's that show preference towards denatured hIL-6, or conformation-specific mAb's. The binding pattern of these two series of mAb's indicated that the IL-6 conformation has been largely destroyed for four of our delta-proteins. Proteins delta 21-51 and delta 127-174 have kept a part of the IL-6 tertiary structure since they are still recognized by some conformation-specific mAb's. All of these delta hIL-6 proteins were inactive in the IL-6 hybridoma growth factor (HGF) assay and unable to inhibit the HGF activity of the recombinant human wild-type IL-6 (wt hIL-6). Moreover, the oocyte-synthesized delta hIL-6 (delta 21-51, delta 127-174, delta 97-184, delta 134-184) did not bind to the IL-6 receptor. Finally, we have produced two proteins with aa 29-33 or 97-104 substituted by corresponding murine IL-6 (mIL-6) sequences.(ABSTRACT TRUNCATED AT 250 WORDS), Journal Article, Research Support, Non-U.S. Gov't, info:eu-repo/semantics/published