Faculty

David T. Rowe, PhD Associate Professor E-mail: rowe1@pitt.edu Phone: 412-624-1529 Fax: 412-383-7490 Address: 435 Parran Hall 130 DeSoto Street Pittsburgh, PA 15261

Education

BSc; University of Guelph; 1975
MSc; University of Guelph; 1977
PhD; McMaster University; 1983

Research Interests

Epstein-Barr Virus Latent Gene Expression

Research Summary

Immunosuppressive therapies used in organ transplantation are associated with the development of Epstein-Barr virus driven lymphoproliferative disease (PT-LPD). Dr. Rowe is conducting a virologic, genetic, and immunologic analysis of the natural history of EBV infection in the immunocompromised host. While much has been learned about the pathologic features of PT-LPDs from laboratory studies of tissue biopsies, the mechanisms governing the evolution of EBV infection into a monomorphic lymphoma and the nature of virus infection either before or following disease remission has not been well characterized. His recent studies show that immunocompromised patients undergo an atypical primary virus-host interaction that leads to the establishment of a chronic high viral load carrier state. Beyond the existence of this high viral load carrier state, little additional information is currently available. He is using newly developed molecular techniques to quantitate the EB viral DNA load in the peripheral blood lymphocytes that are being collected prospectively. The viral load is characterized in terms of the B cell compartment involved, the number of infected cells, the number of viral genomes per infected cell, the patterns of viral gene expression, and the clonality of the infected cell population. When collected prospectively, these data will ultimately provide a clear picture of the course of virus infection that leads to the high load carrier state. The evidence so far suggests that the chronic carrier state is similar to normal latency in that the viral load is carried in the memory B cell pool but unlike normal latency in the pattern of viral genes being expressed. Dr. Rowe is also using a new genotyping technique to detect polymorphisms in the TGFß, TNFa, and IL10 genes that are known to cause variations in the production of these cytokines during the course of immune responses. He suspects there is an impact of these genetic variations on the course and outcome of virus infection. The preliminary analysis suggests a correlation may emerge between low TNFa expression and a risk for developing a chronic high EBV carrier state. Immunologic analyses aimed at directly determining cytotoxic T cell precursor frequencies and lymphocyte subset-specific cytokine secretion profiles are being used to measure actual immune responses. These will eventually be interpreted in relation to the predisposing factors and the course of virus infection. These multi-disciplinary studies on prospectively collected specimens from EBV negative transplant recipients will produce the first clear understanding of the course of EBV infection in the immunocompromised host.

The laboratory also investigates the basic nature of EBV latency in memory B cells. These studies are directed towards determining the role of the LMP2 gene products in the establishment and maintenance of the latent state and characterizing the activity levels of key viral promoters that regulate LMP2 gene expression and the patterns of splicing of transcripts for latency, immortalization, and lytic productive gene products. The functional studies of LMP2 gene products are directed towards determining the role of serine phosphorylation of the LMP2a gene product using point mutants that alter the phosphorylated residues and studying the effects of mutation on protein-protein interactions and the ability of LMP2a to affect cellular signaling processes. Viral gene expression studies are focused on the methylation patterns of viral promoters in infected cells in situ and on the contribution of recently identified promoter sequences and novel splicing arrangements to the regulation of latency.

Recent Publications

• Qu, L., Green, M., Webber, S., Reyes, J., Ellis, D. and Rowe, D. (2000). EBV gene expression in the peripheral blood of transplant recipients with chronic circulating viral loads. J Infect Dis. 39:1013-1021.
• Green, M., Bueno, J., Rowe, D., Mazariegos, G., Qu, L., Abu-Almagd, K., and Reyes J. (2000) Predictive negative value of persistent low Epstein-Barr virus viral load after intestinal transplantation in children. Transplantation 70:593-596.
• Rose, C., Green, M., Webber, S., Ellis, D., Reyes, J., and Rowe D. (2001) Pediatric solid-organ transplant recipients carry chronic loads of epstein-barr virus exclusively in the immunoglobulin d-negative b-cell compartment.  J Clin Microbiol. 39:1407-1415.
• Lynch, D.T., Zimmerman, J., and Rowe, D.T.  (2002).  Epstein-Barr virus latent membrane protein 2B (LMP2B) co-localizes with LMP2A in the perinuclear regions of transfected cells.  J Gen Virol.  83:1025-1035.
• Rose, C., Green, M., Webber, S., Kingsley, L., Day, R., Watkins, S., Reyes, J., and Rowe, D. (2002)  Detection of Epstein-Barr virus genomes in the peripheral blood of solid organ transplant recipients by fluorescent in situ hybridization.  J Clin Micro. 40:2533-2544.
• Jenkins, F.J., Rowe, D.T., and Rinaldo, C.R., Jr. (2003) Herpesvirus infections in organ transplant recipients. Clin Diagn Lab Immunol.  10:1-7.
• Popescu, I., Macedo, C., Zeevi, A., Nellis, J., Patterson, K.R., Logar, A., Rowe, D., Reyes, J., Rao, A.S., Storkus, W.J., Fung, J.J., and Metes, D. (2003) Ex vivo priming of naive T cells into EBV-specific Th1/Tc1 effector cells by mature autologous DC loaded with apoptotic/necrotic LCL. Am J Transplant. 3:1369-1377.
• Wadowsky, R.M., Laus, S., Green, M., Webber, S.A., and Rowe, D. (2003) Measurement of Epstein-Barr virus DNA loads in whole blood and plasma by TaqMan PCR and in peripheral blood lymphocytes by competitive PCR. J Clin Microbiol. 41:5245-5249.
  
• Schauer, E., Webber, S., Green, M., and Rowe, D. (2004) Surface immunoglobulin-deficient Epstein-Barr virus-infected B cells in the peripheral blood of pediatric solid-organ transplant recipients. J Clin Microbiol. 42:5802-5810.
  
• Qu, L., Xu, S., Rowe, D., and Triulzi, D. (2005) Efficacy of Epstein-Barr virus removal by leukoreduction of red blood cells. Transfusion. 45:591-595.
  

Dr. Rowe's Lab