merocyanine-dye and Herpes-Simplex

Membranotropic amphiphilic chromophore merocyanine 540 sensitized photodynamic inhibition of drug-resistant and sensitive variants of type I herpes simplex virus in cultured Vero cell. Optimal conditions of photodamage to virus particles and infected cells were determined (merocyanine 540 concentration 1 microM, illumination dose 32.5-65.0 kJ/m(2), exposure at early stages of infection). Infected cells actively bind the photosensitizer, which explains their selective photodamage.

Topics: Animals; Antiviral Agents; Chlorocebus aethiops; Drug Resistance, Viral; Herpes Simplex; Herpesvirus 1, Human; Humans; Photosensitizing Agents; Pyrimidinones; Vero Cells; Virus Replication

Action spectra of the antileukemic and antiviral activities of merocyanine 540 (MC540) were determined using L1210 leukemia cells and human Herpes simplex virus type 1. The major peak of both action spectra aligned closely with the absorption spectrum of membrane-bound dye monomer, and by implication, the action spectrum of 1O2 generation. These results are compatible with the notion that the antileukemic and antiviral activities of MC540 are primarily attributable to membrane-bound monomer and at least in part mediated by 1O2.

Topics: Animals; Fluorescent Dyes; Herpes Simplex; Humans; Leukemia; Membranes; Mice; Pyrimidinones; Simplexvirus; Spectrophotometry; Tumor Cells, Cultured

Atherosclerotic lesions have been reported to contain herpes simplex virus 1 (HSV-1) genomic material. This, and other previous evidence, suggests that latent viral infection may be an atherogenic trigger. Moreover, active HSV-1 lesions manifest marked fibrin deposition in microvessels. In this report we show that very early infection of human endothelial cells with HSV-1 appears to alter surface conformation as detected by merocyanine 540 staining. Concomitantly, the efficiency of prothrombinase complex assembly increases, resulting in a 2- to 3-fold accelerated rate of thrombin generation on the cell surface. Increased thrombin generation is probably doubly procoagulant, since we also demonstrate that thrombin-induced platelet accumulation on HSV-infected endothelium (50.7 +/- 9.3%) is increased compared to uninfected endothelium (9.5 +/- 2.1%; P less than 0.002). Associated with HSV infection, prostacyclin secretion in response to thrombin is diminished by a factor of 20, probably explaining the enhanced platelet attachment. We conclude that HSV infection shifts endothelial cell properties from anticoagulant to procoagulant, both by promoting prothrombinase complex formation and function and by increasing platelet binding, well before cell disruption takes place. Virus-induced changes in the endothelial plasma membrane and diminished prostacyclin secretion are suggested as the pathways for this pathophysiologic mechanism, which may be germane to atherosclerotic thrombosis as well as HSV-mediated tissue necrosis.

Topics: Arteriosclerosis; Blood Platelets; Cell Adhesion; Cell Aggregation; Endothelium; Herpes Simplex; Humans; Indomethacin; Pyrimidinones; Simplexvirus; Thrombin; Thromboplastin