Plain English Summary
Background and study aims
When people donate their blood platelets, they lose about 50% of them. Although this is perfectly safe, it is not clear how quickly their platelet count returns to normal and what causes this to happen: its possible that new platelets come from a reserve pool in the spleen and/or they are made by bone marrow. It is also not known what chemicals (growth factors) in the blood stream are important in making sure the number of platelets return to normal after donation. Knowing what these platelet growth factors are would be extremely useful for the treatment of patients with low platelet counts or in making platelets in the laboratory for transfusion. This study will compare how quickly the number of platelets return to normal and what growth factors are present in regular donors verses people who are about to donate for the first time.
Who can participate?
Adult male platelet donors who regularly donate at the Cambridge Blood Centre and those that are due to donate for the first time.
What does the study involve?
A blood sample is taken from each participant 30 minutes before the platelet donation begins, in the opposite arm to which the donation is taken from. Another sample is taken 10 minutes after the donation is complete, one 4-8 hours after donation and then a number of additional samples on days 1,3,7 and 14 after the donation are taken. Donors are given the choice whether they would like the bloods to be done at home, place of work or at the Blood Centre.
What are the possible benefits and risks of participating?
There are no significant benefits or risks to taking part in this study. Donations will take around 40 minutes longer than a normal platelet donation. The blood sampling may cause some mild discomfort and sometimes a small bruise.
When is the study starting and how long is it expected to run for?
September 2014 to September 2015.
Who is funding the study?
NHS Blood and Transplant Trust Fund (UK)
Who is the main contact?
Cedric Ghevaert
cg348@cam.ac.uk
Trial website
Contact information
Type
Scientific
Primary contact
Dr Cedric Ghevaert
ORCID ID
Contact details
NHS Blood and Transplant
Cambridge Blood Centre
Long Road
Cambridge
CB2 0PT
United Kingdom
+44 (0) 1223 588904
cg348@cam.ac.uk
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
V2.0
Study information
Scientific title
Reticulated platelet release and mass spectrometry analysis of plasma proteins after apheresis platelet donation by established and new donors
Acronym
Study hypothesis
Platelet donors donate their platelets through a process called apheresis. The donors have a cannula inserted into a vein and this blood line goes into a machine that spins the blood from the donor so as to separate it into different constituents (plasma, red cells, platelets). The red cells and plasma are given back to the donors, whilst the platelets are collected into a bag that can be transfused to a patient. The donation process takes about 1.5 hours. Platelet donors lose about 50% of their platelets, which gradually recover over 2 weeks with the formation of new platelets in the donors bone marrow. We hypothesize that this is driven by growth factors (in addition to thrombopoietin). We seek to identify the exact dynamics of platelet recovery following platelet donation and correlate it to the presence of plasma-bound growth factors through mass spectrometry
Ethics approval
NRES Committee East of England Cambridge South, 22/05/2014, ref: 14/EE/0194
Study design
1-year laboratory study
Primary study design
Observational
Secondary study design
Other
Trial setting
Other
Trial type
Other
Patient information sheet
The donors will be sent out a donor information leaflet, there will also be posters up in the blood centre advertising for donors
Condition
Platelet recovery following donation
Intervention
The donors will have bloods taken pre and post donation and at another four timepoints over the next 2 weeks
Intervention type
Other
Phase
Not Applicable
Drug names
Primary outcome measures
The primary objective of this study will be the accurate measurement of the platelet count, the platelet volume and the quantity of newly formed platelets in platelet apheresis donors at the time of donation and at early (4-8 hours) and late (day 1, 3, 7 and 14) time points after donation. From the same blood sample used to look at the platelet count, we will isolate the plasma and analyse it by mass spectrometry to identify which proteins contained in the blood promote new platelets release from the bone marrow.
Secondary outcome measures
Platelet donors give a donation every 4 weeks. Samples will be taken from established platelet donors and from newly recruited donors to establish whether the platelet count recovery and plasma proteins are different when platelet donations are done frequently.
Overall trial start date
08/09/2014
Overall trial end date
08/09/2015
Reason abandoned
Eligibility
Participant inclusion criteria
Male platelet donors aged over 18 who are able to donate on Monday or Tuesday morning
Participant type
Patient
Age group
Adult
Gender
Male
Target number of participants
30
Participant exclusion criteria
1. Female donors
2. HPA-1a-5b negative donors who are used to maintain the supply of platelets for treatment of neonatal alloimmune thrombocytopenia
Recruitment start date
08/09/2014
Recruitment end date
08/09/2015
Locations
Countries of recruitment
United Kingdom
Trial participating centre
NHS Blood and Transplant
Cambridge
CB2 0PT
United Kingdom
Sponsor information
Organisation
NHS Blood and Transplant Trust Fund (UK)
Sponsor details
Oak House
Reeds Crescent
Watford
WD24 4QN
United Kingdom
+44 (0) 1923 366800
research.office@nhsbt.nhs.uk
Sponsor type
Hospital/treatment centre
Website
Funders
Funder type
Hospital/treatment centre
Funder name
NHS Blood and Transplant Trust Fund (UK)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Results - basic reporting
Publication summary