I would like to know if I can induce platelet aggregation on PRP using only fibrinogen. If yes, what is the concentration of fibrinogen I should use?
Dear Augusto,
maybe I am a bit confused - but why do you want to induce platelet aggregation in platelet poor plasma? Do you want to use it as negative control? There won´t be much platelet aggregation there. Do you want to measure platelet aggregation?
Fibrinogen is not a potent activator of platelet aggregation (that would not be a good thing in our circulation...). Why do you want to use fibrinogen? I´d rather use ADP or Epinephrine...for example.
Platelet poor plasma may even contain high fibrinogen levels by itself...
Maybe I just do not understand the point of your question?
Hi Augusto,
I am not aware of such studies - do you try to establish thrombocyte function tests in thrombopenic patients?
This would be very interesting, as many tests for thrombocytic function require normal thrombocyte counts - and as you can imagine, often patients who bleed do not provide such cell counts...
I am sorry that I could not help you!
Dear Augusto, do you perhaps mean that you are working with isolated platelets in buffer (washed platelet suspensions)? As was said by Julian earlier, platelets fortunately do not spontaneously activate when they meet fibrinogen. At least not in my experience ;) There is evidence for integrin-mediated outside-in signaling, but this is secondary to platelet (pre)activation. Could there be a risk that platelet isolation leads to preactivation? Do you include prostacyclin in your isolation procedure?
@ Julian, there are FACS-based platelet function tests in development to assess platelet function in thrombocytopenia. Some former colleagues have been working on this. A kit is supposed to come out soon
Application of an optimized flow cytometry-based quantification of Platelet Activation (PACT): Monitoring platelet activation in platelet concentrates.
Kicken CH, Roest M, Henskens YM, de Laat B, Huskens D.
PLoS One. 2017 Feb 16;12(2):e0172265. doi: 10.1371/journal.pone.0172265. eCollection 2017.
No, you can not induce aggregation if you use PPP and fibrinogen but you must do it with PRP and minimal concentration of fibrinogen 0,6 g/l.
Hi,
Fibrinogen can not induce platelet aggregation response using PPP.
Best regards.
I would repeat all experiments in the presence of apyrase in order to make sure that the activities measured are not simply a function of ADP released from platelets or erythrocytes during storage and centrifugation. Anyhow,, PPP is probably not a very suitable specimen.