Inactivation of cytomegalovirus in platelet concentrates using Helinx technology

Cytomegalovirus (CMV) infection in immunocompromised patients may result in severe morbidity and mortality. The standard of care for these patients is the use of CMV-seronegative blood components. Alternatively, filtered, leukocyte-reduced blood components have been used. However, neither approach completely prevented transfusion-associated CMV infection in the recipients. The Helinx technology (Cerus Corp, Concord, CA) utilizing amotosalen hydrochloride (HCl) (S-59) and long-wavelength ultraviolet A (UVA) light, was developed to enhance the safety of platelet transfusion. The combination of 150 micromol/L of S-59 and a 3 J/cm2 UVA treatment inactivated greater than 10(5.9 +/- 0.3) plaque-forming units (pfus) per milliliter of CMV in full-sized therapeutic platelet concentrates. The efficacy margin of this treatment is greater than 100-fold. In an immunocompromised in vivo murine transfusion model, mice transfused with platelets contaminated with murine CMV (MCMV)-infected splenocytes became MCMV-positive, exhibited histologic evidence of CMV disease, and died. Mice transfused with Helinx-treated platelets contaminated with MCMV-infected splenocytes prior to treatment remained MCMV-negative with no histologic evidence of CMV disease and remained healthy. These results demonstrated that Helinx treatment of MCMV-contaminated platelet concentrates prevented MCMV infection by platelet transfusion in immunodeficient animals. In conclusion, Helinx technology offers a potential alternative to selection of CMV-seronegative units and to leukocyte-reduction filtration as a means to decrease the risk of transfusion-acquired CMV infection.