title: Effects of two viral inactivation methods on platelets: laser-UV radiation and merocyanine 540-mediated photoinactivation.
abstract: Two viral inactivation methods suggested for use with cellular blood products have been evaluated as to their effects on platelets. In the first study, it was proposed that pulsed laser-ultraviolet radiation (UVB) at 308 nm could favor photodamage to UVB-sensitive viral nucleic acid with minimal effects on blood platelets. A "window of efficacy" was observed with UVB doses of 10.5-21.5 J/cm2 at which 4-6 log10 poliovirus were inactivated while platelets were relatively tolerant. However, this "window" occurred only with low-intensity UVB radiation (less than or equal to 0.25 MW/cm2). Damage to platelet proteins, evident at high laser intensities, was probably due to multiple photon excitation of amino acids. In the second study, platelets and viruses were treated with the photosensitizer, merocyanine 540 (MC 540) (less than or equal to 24 micrograms/ml), and visible light (450-600 nm) (less than or equal to J/cm2). Activation of washed platelets by dye/light treatment resulted in a spontaneous release of serotonin, spontaneous aggregation, and marked morphological changes. Increasing concentrations of albumin in the suspension medium protected against dye-mediated photodamage to platelets, but also significantly reduced the antiviral activity of MC 540 and light. These results illustrate the relative sensitivities of platelets and viruses to two inactivation methods and the difficulty in optimizing inactivation of viruses and preservation of platelet function in a protein-rich medium.
authors.affiliation: Center for Biologics Evaluation & Research, FDA, Bethesda, Maryland 20892.
authors.forename: K N
authors.initials: KN
authors.lastname: Prodouz
authors.forename: C D
authors.initials: CD
authors.lastname: Lytle
authors.forename: R F
authors.initials: RF
authors.lastname: Bonner
authors.forename: J C
authors.initials: JC
authors.lastname: Fratantoni
mesh_terms: D001769:Blood / Q000382:microbiology; D001792:Blood Platelets / Q000187:drug effects / Q000382:microbiology* / Q000528:radiation effects; D001798:Blood Proteins / Q000187:drug effects / Q000528:radiation effects; D004249:DNA Damage; D006801:Humans; D007834:Lasers; D010777:Photochemistry; D015539:Platelet Activation / Q000187:drug effects / Q000528:radiation effects; D011744:Pyrimidinones / Q000494:pharmacology* / Q000528:radiation effects; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology* / Q000528:radiation effects; D014466:Ultraviolet Rays / Q000009:adverse effects; D014777:Virus Diseases / Q000517:prevention & control / Q000635:transmission; D018406:Virus Physiological Phenomena; D014779:Virus Replication / Q000187:drug effects / Q000528:radiation effects; D014780:Viruses / Q000187:drug effects* / Q000528:radiation effects
chemical_list: D001798:Blood Proteins; D011744:Pyrimidinones; D011838:Radiation-Sensitizing Agents; C003954:merocyanine dye