Interaction between human cytomegalovirus UL136 protein and ATP1B1 protein

Interplay between the host and human cytomegalovirus (HCMV) has a pivotal role in the outcome of infection. A region (referred to as UL/b’) present in the Toledo strain of HCMV and low passage clinical isolates contains 19 additional genes, which are absent in the highly passaged laboratory strain AD169. Products of the UL/b’ genes may determine the manifestations of HCMV infection in vivo. However, little is known about the host factors, which interact with UL/b’ proteins. This study was conducted to investigate the function of the HCMV UL136 protein. By yeast two-hybrid screening, the β1 subunit of the host Na+/K+-ATPase (ATP1B1) was identified to be a candidate protein, which interacts with the HCMV UL136 protein. The interaction was further evaluated both in vitro by pull-down assay and in vivo by immunofluorescent co-localization. The results showed that the UL136 protein can interact with ATP1B1 in vitro. Co-localization of UL136-EGFP and ATP1B1-DsRed in cell membranes suggests that ATP1B1 was a partner of the UL136 protein. It can be proposed that the HCMV UL136 protein may have important roles in processes such as cell-to-cell spread, and in maintaining cell osmotic pressure and intracellular ion homeostasis during HCMV infection.

role of clinical, therapeutic and laboratory findings in monitoring of HCMV infection in bone marrow transplant recipients

Human cytomegalovirus [HCMV] has been an enormous threat for bone marrow transplant [BMT] recipients. For active and/or latent HCMV infection, diagnosis of the risk factors which increase the risk of posttransplant morbidity and mortality seems necessary. In this research, some of the HCMV risk factors were monitored and compared with HCMV molecular diagnostic methods for better detection of HCMV infection in BMT patients. HCMV risk factors including clinical, biological, biochemical, haematological indexes, and also anti-HCMV and transplant prophylactic and therapeutic conditioning regimens were monitored from March 2002 to March 2006, in 104 BMT patients referred to BMT Unit of Nemazee Hospital in Shiraz University of Medical Sciences and was compared with HCMV molecular methods for BMT donors and recipients' pre- and posttransplantation. Anti-HCMV-lgM was detected in 9.6% and 6.7% of BMT recipients and donors, respectively. Anti-HCMV-lgG was also detected in 8.7% and 9.1% of recipients and donors, pre-transplant, respectively. HCMVPCR results were positive in 20% of recipients and 33.3% of donors. Significant correlations were observed between HCMV positive results and the use of a therapeutic dose, but not the prophylactic dose of glucocorticoids and cyclosporine, pre and post-transplantation. Fasting blood sugar, creatinine, globulin, and liver enzymes levels such as alkaline phosphates and asparagine transpherase significantly correlated with detection of HCMVDNA in transplant patients. Also, negative results of HCMV-PCR significantly correlated with the use of prophylactic dose of acyclovir in BMT patients. Significant correlations of positive and negative HCMV-PCR results with HCMV disease risk factors suggest the possible role of these factors on prognosis and monitoring of HCMV disease in BMT recipients preand post-transplantation

Use of nested polymerase chain reaction for the detection of cytomegalovirus in clinical specimens.

BACKGROUND & OBJECTIVES: Since fluorescent antibody test (FAT) has low sensitivity in the rapid detection of cytomegalovirus (CMV) in clinical specimens, a nested polymerase chain reaction (nPCR) to detect the CMV-DNA was evaluated. METHODS: nPCR and FAT were carried out to detect CMV in single specimens from 104 patients and dual specimens from 32 patients with suspected active CMV infection. Of the 136 patients, 3 were HIV positive. RESULTS: CMV was detected by FAT alone in 3 (1.8%) and FAT and nPCR in 16 (9.5%) specimens and by nPCR alone in 84 (50.0%) specimens from 74 (54.4%) patients. nPCR increased the clinical sensitivity by 50.0 per cent in the specimens and 54.4 per cent in the patients (McNemar test, P < 0.001). Urine was found to be the ideal specimen for the detection of CMV as the detection rate in the urine was statistically higher (McNemar test, P < 0.05) than in the blood. Buffy coat and plasma samples from 35 normal blood donors were subjected to nPCR and ELISA respectively. CMV-DNA was not detected in any of the samples while anti-CMV antibodies were detected in all of them. INTERPRETATION & CONCLUSION: The results showed that presence of CMV-DNA in the specimen indicates active infection and nPCR is a rapid, sensitive, specific and a more reliable diagnostic tool than FAT.