Background : Febrile, nonhemolytic transfusion reactions are the most frequent adverse
reactions to platelet transfusion with the incidence of 5 to 30%. The mechanism of
reactions to transfused platelets is not well understood. It is generally assumed that
they are caused by the interaction of antileukocyte alloantibodies. But, febrile reactions
can occur in the patients who have never received any transfusion and are more likely
with platelets that have been stored than with relatively fresh platelets. These
observations suggest that bioreactive substances like interleukin-lβ(IL-lβ) and
interleukin-6(IL-6) produced in platelet concentrates during storage, could mediate febrile
nonhemolytic reactions caused by platelet transfusion. So, we compaired the effect of
leukocyte depleting filter and γ-radiation to suppress the elevation of IL- lβ and IL-6
in platelet concentrates during storage.
Method: Ten units of platelet concentrate were used. Each unit was divided into 3
groups. Group 1 was unprocessed group. Group 2 was irradiated group with γ-ray(3.5
Gy). Group 3 was filtered group with Sepacell PL-5ATM. The concentrates were then
stored at 22℃ with horizontal agitation for 7 days. Samples for cytokine measurement
and bacterial culture were taken from each concentrate on days 1, 3, 5 in Group 1 and
day 1, 3, 5, 7 in group 2 and 3. IL-lβ and IL-6 were measured with an enzyme-linked
immunoassay(T cell diagnostics Inc, UK). For the evaluation of Sepacell filter effect, the
platelet count was done manually with Neubauer chamber and the hemoglobin and white
blood cell levels were automatically measured.
Results :
1) IL-lf(pg/mL): At day 1, mean IL-lβ level was equally 0.1 in group 1, 2, and 3. At
day 3, mean IL-lβ level of group 1, 2 and 3 were 7, 4.6 and 1.3, respectively. At day 5,
mean IL-lβ level of group 1, 2 and 3 were 59, 41 and 4.5, respectively. At day 7, IL-l
β level of group 2 and 3 were 120.5 and 13, respectively. At day 3, difference of group
1 and 2 was not statistically significant (P=0.07) but differences of Group 1 and 2 &
group 1 and 3 were statically different(P<0.05). At day 5 and 7, the differences of each
group were statistically significant(P<0.05).
2) IL-6(pg/mL): At day 1, mean IL-6 level was equally 25.5 in group 1, 2, and 3. At
day 3, mean IL-6 level of group 1, 2 and 3 were 78.5, 57.5 and 42.5, respectively. At
day 5, mean IL-6 level of group 1, 2 and 3 were 9,900, 303.5 and 56.5, respectively. At
day 7, IL-6 level of group 2 and 3 were 795 and 63, respectively At day 3, 5 and 7, the
differences of each group were statistically significant(P<0.05).
3) Sepacell filter effect: The mean WBC count at prefiltration was 410/μL and that of
prostfiltration was 15/μL. And so, the effect of filtration was 99.6%. Prefiltration levels
of hemoglobin and platelet were 0.27g/dL and 1,185×10³/μL, respectively. Postfiltration
levels of hemoglobin and platelet were 0.21g/dL and 1,162×10³/μL.
4) Bacterial culture: No growth of bacteria was found in group 1, 2 and 3.
Conclusion: We could observe the increased IL-lβ and U-6 with the prolongation of
platelet concentrates storage time. And the use of leukocyte depleting filter was more
effective than γ-radiation to suppress the elevation of IL- lβ and IL-6 in platelet
concentrates during storage.

Keywords: Platelet, Cytosine, Sepacell filter, γ-Radiation