Six filters for the removal of white cells from red cell concentrates, evaluated at 4 degrees C and/or at room temperature

BACKGROUND: Six filters were tested for their ability to remove white cells from buffy coat-depleted reef cell concentrates at various temperatures. STUDY DESIGN AND METHODS: Cellselect FR, BPF4, and Sepacell filters were te sted at both room temperature (RT) and 4 degrees C. The Leucoflex filter wa s tested only at 4 degrees C, while the Cellselect Optima Plus and Imugard filters were tested only at RT. Donor-dependent differences were excluded b y pooling and subsequently dividing 9 red cell concentrates; 12 sets of exp eriments were performed. RESULTS: With all filters, red cell concentrates containing <5 x 10(6) whit e cells per unit were obtained. The lowest numbers of residual white cells were achieved with the Leucoflex (at 4 degrees C, 0.15 +/- 0.11 x 10(6)), t he Sepacell (at 4 degrees C, 0.23 +/- 0.14 x 10(6)), the Imugard (at RT, 0. 24 +/- 0.14 x 10(6)), and the BPF4 (at 4 degrees, 0.25 +/- 0.24 x 10(6); di fferences not significant). With the Cellselect FR, filtration at 4 degrees C resulted in 0.86 +/- 0.37 x 10(6) white cells per unit, a level not sign ificantly different from that obtained with the BPF4 and Sepacell filters a t RT (1.16 +/- 0.43 x 10(6) and 0.80 +/- 0.36 x 10(6) white cells, respecti vely). Filtration at RT with the Cellselect FR and Cellselect Optima Plus r esulted in red cell concentrates with 1.79 +/- 0.69 x 10(6) and 2.29 +/- 0. 69 x 10(6) white cells, respectively (p<0.01). CONCLUSION: All filters conformed to the current standards for white cell r eduction; the process was less efficient at RT than at 4 degrees C. For rou tine application, the composition of the red cell concentrate, the temperat ure, and logistic preferences should be taken into account in the final cho ice of filter; before implementation, the chosen filter must be validated u nder routine conditions.