In vitro and in vivo evaluation of leukoreduced platelets stored for 7 days in CLX containers

Abstract

Extension of platelet (PLT) storage and concomitant use of a bacterial detection system would provide logistical advantages by reducing outdating and improving patient care through promotion of the use of sensitive detection systems. This study evaluated the in vitro characteristics and in vivo viability of leukoreduced PLT units derived from PLT-rich plasma stored for 5 days (control) versus 7 days (test) in CLX plastic containers. Two whole-blood units were collected from each subject into a leuko-reduction filtration system (Leukotrap RC-PL system, Pall Medical) in a paired design, the second 2 days after the first. These were leukoreduced (Leukotrap PL) and stored for 7 and 5 days. Poststorage samples from test and control units were randomly labeled with (51)Cr or (111)In and simultaneously infused autologously to determine recovery and survival. Small but significant (p < 0.05, paired t test) differences between 5 and 7 days of storage were seen in in vitro variables such as extent of shape change, hypotonic shock response, morphology, and P-selectin expression. In vivo recovery declined on average 11 percent with the two additional days of storage from 54.4 +/- 13.6 to 48.7 +/- 15.0 percent (p < 0.002); survival decreased on average 19 percent from 6.7 +/- 1.0 to 5.4 +/- 1.7 days (p < 0.002). Storage for 7 days was associated with reduced recovery and survival and in vitro variables, suggestive of extension of the storage lesion. These differences, however, were small in magnitude and unlikely to have significant clinical effects. Current collection and storage systems provide PLTs that are as functional at 7 days as those licensed for 7-day storage two decades ago.