This is a platelet transfusion study. The purpose of this study is to measure the life span and quality of platelets stored in a refrigerator. Participants will give platelets by apheresis. Platelets will be stored for 3 -20 days. A small portion of the subject's own stored platelets will be tagged with a radioactive isotope and infused back into the participant. This will enable us to track how many transfused platelets survive after storage in the refrigerator.
A single hyperconcentrated apheresis platelet unit will be collected from a healthy adult volunteer subject using the Trima Accel® Automated Blood Collection System. Concurrent plasma will be collected. The platelet unit will be stored, not-agitated, for up to 20 days at 4°C in a suspension of 35% plasma and 65% PAS (Platelet Additive Solution). At the end of the storage period, the subject will return to receive an 111Indium Oxine (Indium 111, In-111) radiolabeled aliquot of their 4°C stored platelets. Follow-up samples from the subject will be collected approximately 2 hours post-infusion and on Days 1 (2X), 2 (2X), and 3 to calculate recovery and survival of the subject's 4°C stored platelets. The Day 1 and Day 2 the sample draws will be 2 - 10 hours apart. In addition to radiolabeled platelet recovery and survival measurements, various in vitro assays will be performed on the day of collection at the end of 4°C storage. One week after the infusion of the radiolabeled aliquot, the subject will return to receive a second radiolabeled aliquot of fresh platelets. To facilitate this, on the morning of the second infusion, the subject will return for collection of a 43 mL blood sample. The blood will be processed to obtain a fresh sample of the subject's platelets to serve as a control comparator. The platelets will be radiolabeled with In-111. The subject will return later in the day for infusion of the radiolabeled fresh 'control' comparator aliquot. Follow-up blood samples will be drawn at \~2 hours after the infusion on Day 0 and then on Days 1, 2, 3, 4 or 5, and 6 or 7 day post infusion to calculate recovery and survival of the subject's fresh vs. stored platelets.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
BASIC_SCIENCE
Masking
NONE
Enrollment
80
A single apheresis platelet unit will be collected from a healthy adult volunteer subject using the Trima Accel® Automated Blood Collection System. Concurrent plasma will be collected.
The apheresis platelet unit will be stored, without agitation, at 4°C, for up to 20 days.
Fresh and stored aliquots will be labeled with Indium-111. We are administering ≤30 microcuries in both infusions for a total dose of 0.8 mSv.
Bloodworks Northwest (formerly Puget Sound Blood Center)
Seattle, Washington, United States
RECRUITINGMaximal storage time with acceptable recovery and survival (as defined below)
Tables of recovery and survival summary statistics will display values by group from fresh and stored platelets. Recovery and survival of stored platelets as percentage of corresponding fresh platelets will be plotted against days stored. Regression methods will be used to determine if there is evidence of any trend in the mean storage or recovery of 4°C stored platelets with respect to storage time as a percentage of each subject's fresh platelet results. Histograms of recovery and survival as percentage of 4°C stored platelet measurements will be plotted, and corresponding confidence intervals will be calculated.
Time frame: up to 20 days storage at 4°C
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Tests to evaluate platelet function will be performed on the platelet unit on day of collection and end of storage