Development of models and detection methods for different forms of cytomegalovirus for the evaluation of viral inactivation agents.

BACKGROUND: Cytomegalovirus (CMV) is transmitted by transfusion of infected blood products and can cause serious diseases in specific risk groups. CMV can be present in infected blood as cell-free virus (CFV), cell-associated actively replicating virus (CAV), and cell-associated latent virus (LV). STUDY DESIGN AND METHODS: In vitro models for all three infectious forms of CMV and virus detection assays based on both tissue culture and polymerase chain reaction (PCR) were developed. The utility of the CMV model systems and assays were tested by validation studies of a novel pathogen inactivation agent, PEN110, for red blood cells. RESULTS: Reproducible high titers of CFV and CAV were obtained by optimized tissue culture techniques for CMV-infected MRC-5 cells. An LV model was obtained with CMV-infected THP-1 cells and reactivation of virus replication by phorbol ester treatment. The model systems showed that PEN110 treatment is effective against all three forms of CMV as measured by tissue culture-based infectivity assays and a long-range PCR method specific for detection of damage to CMV viral DNA. CONCLUSION: This study describes model systems to the relevant forms of CMV in blood and detection assays that can be used to evaluate the efficacy of viral inactivation agents.

Inactivation of HIV in blood.

BACKGROUND: The residual risk of HIV infection after HIV screening tests in combination with the risk of new emerging pathogens entering the blood supply has sparked research on the development of a technology for reduction of pathogens in RBCs. STUDY DESIGN AND METHODS: HIV-1 was treated with PEN110 (INACTINE) and analyzed for the kinetics of virus reduction in RBC, the effect of PEN110 on nucleic acids, the integrity of the virus morphology and viral proteins, and the ability of the virus to bind HIV cell receptors and enter susceptible cells. RESULTS: PEN110 effectively reduced HIV-1 to the limit of detection for a reduction factor of at least 5.57 log 50 percent tissue culture infectious dose per bulk test. The PEN110-treated virions maintained their morphology, protein integrity, and functionality. However, the PEN110-treated HIV-1 RNA genome was neither functional to serve as a template for RT-PCR amplification of about 1 kb nor able to support viral DNA synthesis in cell culture. CONCLUSION: These results suggest that PEN110 inactivates HIV-1 by targeting the viral nucleic acid.