BACKGROUND AND OBJECTIVES

The INTERCEPT Blood System for Platelets utilizes amotosalen-HCl (S-59) in combination with ultraviolet A (UVA) light to inactivate viruses, bacteria, protozoa and leucocytes that may contaminate platelet concentrates (PCs). To facilitate implementation of this technique into routine blood bank manufacturing procedures, this study evaluated the impact of different time settings of photochemical treatment on in vitro platelet function.

MATERIALS AND METHODS

Platelets derived from apheresis (6.5-7.0 x 10(11) platelets) were resuspended in 240 ml of autologous plasma and 360 ml of platelet additive solution (PAS III) and split into two equal-sized PC units. Whereas one unit was not treated, the other was treated with 150 microm amotosalen and 3 J/cm2 UVA light followed by a compound adsorption device (CAD) step for reduction of residual amotosalen and photoproducts. In a first series of experiments (arm A, n = 7), PC units were photochemically treated after an overnight storage period of 16-23 h followed by a CAD step of 4 h. In a second series (arm B, n = 8), photochemical treatment occurred after a short storage time of 4 h with a subsequent CAD step of 16 h. Platelet function was evaluated by assaying blood gas analysis, glucose and lactate concentration, lactate dehydrogenase (LDH), hypotonic shock response (HSR) and the expression of CD62p, over a period of 7 days.

RESULTS

Neither of the photochemical treatment procedures showed differences for pH, pCO2, pO2, HCO3, glucose consumption or platelet activation until the end of day 7. Increased lactate values detected for the treated units of arm A at the end of the storage period were independent from the PCT time setting.

CONCLUSIONS

Photochemical pathogen inactivation with different initial resting periods between 4 and 23 h, and different CAD steps of 4 and 16 h, had no influence on the platelet in vitro function during 7 days of storage.