Patent EA-004246-B1 (EA)
Title: Photodynamic treatment and uv-b radiation of a thrombocyte suspension
Inventor: MOHR HARALD
IPC: A61L2/10
Filed: 2001-07-04
Abstract: 1. A method for treatment of a platelet suspension comprising the following steps: (A) exposure of the suspension to radiation in a wavelength range of 400 to 750 nm in the presence of one or several photoactive substances which have one or several absorption maximal in the wavelength range, and (B) exposure of the suspension to radiation in a wavelength range of 270 to 320 nm, the energy input is 0.1 to 10 J/cm<2>, wherein steps (A) and (B) can be used in arbitrary order and/or overlapping in time, and in step (B) there is no photoactive substance present which has an absorption maximum in the wavelength range of the radiation according to step (B). 2. The method according to claim 1, characterised in that the photoactive substance is a phenothiazine dye. 3. The method according to claim 2, characterised in that thionine, methylene blue, toluidine blue and/or the azure dyes A, B and C are used as phenothiazine dyes. 4. The method according to one of claims 2 or 3, characterised in that the photoactive substance in step (A) is used in a concentration of 0.5 to 10 muM, preferably 0.5 to 5 muM. 5. The method according to one of the preceding claims, characterised in that the intensity of the radiation in step (B) is set such that the proliferation capability of T-lymphocytes contained in the platelet concentrates is reduced by at least 50 %, preferably by more than 75 %. 6. The method according to one of the preceding claims, characterised in that in step (B) the energy input is 0.1 to 10 J/cm<2>, preferably 0.5 to 3 J/cm<2>. 7. The method according to one of the preceding claims, characterised in that in step (B) the suspension is exposed to radiation in a wavelength range of 290 to 320 nm. 8. The method according to one of the preceding claims, characterised in that the platelet suspensions are platelet concentrates. 9. The method according to one of the preceding claims, characterised in that the platelet suspensions or platelet concentrates were obtained from blood donation or by platelet apheresis. 10. The method according to one of the preceding claims, characterised in that the treatment of the suspension in accordance with step (A) and/or step (B) takes place in plastic containers transparent to the appropriate radiation. 11. The method according to one of the preceding claims, characterised in that the treatment of the suspension in accordance with step (A) and/or step (B) takes place in a flow-through apparatus transparent to the appropriate radiation. 12. The method according to one of the preceding claims, characterised in that the virus concentration of the suspension is reduced by at least 5, preferably by at least 6 log10 steps. 13. A method for treatment of a platelet suspension comprising the following steps: (A) exposure of the suspension to radiation in a wavelength range of 400 to 750 nm in the presence of one or several photoactive substances which have one or several absorption maximal in the wavelength range, and (B) exposure of the suspension to radiation in a wavelength range of 270 to 320 nm, the energy input is 0.1 to 10 J/cm<2>, wherein steps (A) and (B) can be used in arbitrary order and/or overlapping in time.