SHELF-LIFE OF PHOTODYNAMICALLY STERILIZED RED-CELL CONCENTRATES WITH VARIOUS NUMBERS OF WHITE CELLS

BACKGROUND: Phthalocyanines are useful sensitizers for the photodynami c sterilization of red cell concentrates. The use of the phthalocyanin e Pc4 (HOSiPcOSi-(CH3)(2)(CH2)(3)N(CH3)(2)) and red light is very effi cient in killing various viruses. The addition of scavengers of Type I photodynamic reactions and the use of cremophor to deliver Pc4 give p rotection to the red cells. STUDY DESIGN AND METHODS: Various red cell components, either white cell-enriched, buffy coat-removed, or white cell-reduced, have been used to study the effect of photodynamic treat ment with Pc4 on hemoglobin and potassium leakage and on ATP and gluco se levels after prolonged storage. RESULTS: After treatment, storage i nterval-dependent damage to the red cells could be observed. In compon ents with 26 x 10(9) white cells per L, virus inactivation was less ef ficient than that in components with no or 2 x 10(9) white cells per L . Similarly, red cells were less affected by the treatment in componen ts with a large number of white cells. Pretreatment storage and use wi thin 1 week after photodynamic treatment induce less damage to the red cells at the moment of transfusion. CONCLUSION: Various improvements in the treatment protocol may ultimately lead to the implementation of photodynamic treatment in transfusion practice. In this respect, the white cell content of the red cell concentrates should be taken into a ccount.