Measurement of the activation of equine platelets by use of fluorescent-labeled annexin V, anti-human fibrinogen antibody, and anti-human thrombospondin antibody.

The research investigates the use of fluorescent-labeled annexin V and anti-human fibrinogen antibody to detect the activation of equine platelets through flow cytometry, with potential applications in identifying horses at risk of thrombotic disorders. Anti-human thrombospondin antibody was found ineffective for this purpose.

Research Methodology

• The research involves platelets obtained from six Thoroughbreds. The study uses flow cytometry, a technique that measures the properties of cells, to assess platelet activation.
• Platelet activation is observed by detecting the binding of fluorescent-labeled annexin V, anti-human fibrinogen antibody, and anti-human thrombospondin antibody to both unactivated and activated equine platelets. The platelets in this study get activated using ADP, collagen, platelet activating factor (PAF), and A23187.
• Human platelets are also used in the study for comparison purposes. The 14C-serotonin uptake and release are measured to determine the extent of platelet secretion. This step helps in understanding the level of activation in the platelets.

Research Findings

• The study found that the anti-human thrombospondin antibody did not bind to equine platelets. It means it’s ineffective in detecting the activation of equine platelets.
• Meanwhile, the Annexin V showed binding to equine platelets when they were activated with PAF or A23187 and had undergone secretion. Similarly, the anti-human fibrinogen antibody bound to ADP-, PAF-, and A23817-activated platelets. This binding process wasn’t dependent on platelet secretion.
• However, the study also observed that the extent of binding of the anti-human fibrinogen antibody was lesser in equine platelets than human platelets, even in the case of maximal stimulation.

Conclusions and Future Scope

• The study concludes that the activation of equine platelets can be detected using fluorescent-labeled annexin V and anti-human fibrinogen antibody. However, anti-human thrombospondin antibody is not feasible for detection purposes.
• These flow cytometric techniques have potential applications in detecting in vivo platelet activation in horses at risk of developing thrombotic disorders, which are diseases related to blood clot formation.