Prestorage and bedside leucofiltration of whole blood modulates storage-time-dependent suppression of in vitro TNF alpha release

Immunosuppression after transfusion may be related to the content of leucoc ytes in the transfused blood. Therefore we studied the effects of prestorag e and bedside leucodepletion by filtration on the suppression by whole bloo d of in vitro stimulated tumour necrosis factor alpha (TNF alpha) release, Nine units of whole blood were leucofiltered prestorage and stored for 35 d , 27 units, 3 x 9, were stored and leucofiltered at the bedside after 7, 21 and 35d, Supernatants were collected from all units during storage and add ed to a whole blood assay of E. coli-LPS-stimulated TNF alpha release. The effects of storage were assessed and compared with supernatants collected i mmediately after donation as reference. TNF alpha release was storage time dependently suppressed to: 81%, 74% and 57% by supernatants from non-filter ed blood stored for 7, 21 and 35d, respectively. Prestorage leucofiltration almost eliminated this effect, but we still observed a storage-time-depend ent suppression by bedside-leucofiltered blood to 88%, 78% and 65%, respect ively Prestorage leucofiltration appeared to reduce storage-time-dependent suppression of in vitro stimulated TNF alpha release induced by plasma from whole blood compared with non-filtered and bedside-leucofiltered whole blo od.