Microcytotoxicity assay for platelet antibodies using fresh and frozen fluorescein-labeled target platelets.

We describe our results with a microtoxicity assay that uses fluorescein-labeled platelets for the detection of auto-, iso-, and allo-immune platelet antibodies. The system has a number of advantages in that it is not only rapid but can accommodate multiple test specimens, requires minimal reagents, and can utilize both fresh or frozen donor platelets as the target cells. The latter attribute may allow for the development of a platelet blood banking system with more efficient platelet cross-matching capabilities.