Kaposi's sarcoma-associated herpesvirus (KSHV) is the aetiologic agent of Kaposi's sarcoma (KS), a tumour of endothelial cell origin. The study of KS development was aided by the generation of a recombinant GFP (latent)/RFP (lytic)-expressing KSHV (rKSHV.219) by Vieira and O'Hearn (2004). In this study the first data characterising primary endothelial cell infection and transmission with this virus is presented. Infection was predominantly latent and the percentage of GFP-positive cells increased over time. Neither horizontal transmission of infection, nor cellular proliferation, explained this increase. Analysis of latency-associated nuclear antigen (LANA-1) expression revealed that a threshold level of infection was required for GFP expression early post infection. At later time points GFP correlated more closely with LANA-1 expression, likely due to the accumulation of GFP over time. This study provides methodological guidance for the use of rKSHV.21. In addition, it highlights potential problems associated with the use of fluorescent proteins as markers of viral infection.
Bibliographical noteFunding Information:
This work was funded by a University of Birmingham College of Medical and Dental Sciences post-graduate research studentship (HJ), a Cancer Research UK grant ( C7934 ) to LMB, GN and DJB and grants to DJB from the Medical Research Council ( G0400408, G0800154 ). The authors acknowledge Jeff Vieira for the generous provision of rKSHV219-infected Vero cells and BacK50 baculovirus.
- Endothelial cell
- Kaposi's sarcoma-associated herpes virus