Storage of apheresis platelets in lipaemic plasma affects aspects of platelet function and surface receptor expressionDianne E. van der Wal, Claire Linnane, Htet Htet Aung, Rachel Webb, Denese C. Marks. Research and Development, Australian Red Cross Lifeblood, Sydney, Australia

Lipaemia in blood donations is usually due to consumption of a high fat meal prior to donating, a metabolic disorder or side-effects of medication. Whilst the effect of lipaemic plasma on red cell storage has been investigated, there is little data regarding the quality of platelets stored in lipaemic plasma. The visual

appearance of lipaemic platelet concentrates prevents the detection of swirl, and often raises questions concerning the safety and quality of those products; hence they are often discarded. Given the paucity of data, we investigated the effect of storing apheresis platelets in lipaemic plasma.

BACKGROUND

CONCLUSION

Storage of platelets in lipaemic plasma does not affect platelet metabolism, but differentially affects platelet receptor expression and their ability to respond to agonists. This may reduce

their efficacy upon transfusion, warranting further investigation.

Australian governments fund Australian Red Cross Lifeblood to provide blood, blood products and services to the Australian community.

RESULTSMETHODS

Figure 2. Storage in lipaemic plasma does not affect platelet metabolism. On day 1 post-collection, either normal, moderately (MOD) or severely (SEV)

lipaemic plasma was added to apheresis platelets (40% plasma/60% SSP+). Platelets were tested on the indicated days and A. platelet count, B. pH, C. glucose

and D. lactate were measured. Data were analysed using a two-way repeated measures ANOVA;* indicates p< 0.05. Data represent mean ± SD (MOD group n

= 5; SEV group n = 6).

Figure 4. Storage in lipaemic plasma reduces TRAP-induced P-selectin expression and mitochondrial polarisation. On day 1 post-collection, either

normal, moderately (MOD) or severely (SEV) lipaemic plasma was added to apheresis platelets (40% plasma/60% SSP+). Platelets were tested on the indicated

days and A. CD62P (P-selectin), B. CD62P following stimulation with 1 µM TRAP-6; C. Annexin-V (phosphatidylserine exposure) and D. TMRE fluorescence

(mitochondrial polarisation) were measured by flow cytometry. Data were analysed using a two-way repeated measures ANOVA;* indicates p< 0.05. Data

represent mean ± SD (MOD group n = 5; SEV group n = 6).

Figure 3. Storage In lipaemic plasma reduces platelet adhesion receptors.

On day 1 post-collection, either normal, moderately (MOD) or severely (SEV)

lipaemic plasma was added to apheresis platelets (at 40% plasma/60% SSP+).

On the indicated days A. GPIbα, B. GPVI and C. CD61 were measured using flow

cytometry. Data were analysed using a two-way repeated measures ANOVA;*

indicates p< 0.05. Data represent mean ± SD (MOD group n = 5; SEV group n =

6).

Figure 5. Storage in lipaemic plasma does not affect clot forming ability. On day 1 post-collection, either normal, moderately (MOD) or severely (SEV)

lipaemic plasma was added to apheresis platelets (40% plasma/60% SSP+). Platelets were tested on the indicated days. Platelets were diluted in Tyrode’s

buffer (200x109/L); kaolin and calcium were added prior to performing thromoboelastography. A. R time, B. Angle and C. MA. Data were analysed using a two-

way repeated measures ANOVA;* indicates p< 0.05. Data represent mean ± SD (MOD group n = 5; SEV group n = 6).

Figure 1. Methods. On day 1 post-collection, a double apheresis platelet donation was centrifuged (1350 x g, 10 min, no break), plasma was removed by manual

press and platelets were resuspended in a solution of either whole blood derived non-lipaemic (normal), moderately (MOD) or severely (SEV) lipaemic plasma

(40% plasma/60% SSP+). The platelet were stored in normal (control) vs. moderate or severely lipaemic plasma, and sampled on day 1, 5 and 7 post-collection.

Examples of normal, moderately and severely lipaemic plasma are shown.