INTERCEPT Blood System for Plasma
Because plasma is frozen under conditions that do not promote preservation of intact cells, TA-GVHD caused by leukocytes is of significantly less concern in frozen plasma than in other blood components. However, T-cells may retain functionality after freezing and TA-GVHD has been reported to result from transfusions of conventional plasma not treated with gamma irradiation. Two assays were used to evaluate inactivation of leukocytes: frequency of adduct formation in leukocyte DNA and limiting dilution assay to detect clonal expansion of viable T-cells. The results of these studies in plasma indicate effective inactivation of T-cells and leukocytes (see Table 4). The adduct frequency demonstrated is sufficient to ensure inactivation of most individual genes.
Table 4: Inactivation Claims - Leukocytes
|Assay||Extent of Inactivation|
|DNA modification||Approximately one amotosalen adduct per 89 base pairs|
|Limiting dilution assay||≥6.1 log10 reduction of viable T-cells|