Washed Equine Platelet Extract as an Anti-Inflammatory Biologic Pharmaceutical.

This research study revolves around the development of a new platelet extract, the washed equine platelet extract (WEPLEX), produced from equine blood platelets. The researchers propose WEPLEX as an improved therapy for tissue regeneration and healing, exhibiting better anti-inflammatory qualities and fewer risks when compared to existing treatments.

Understanding Mammalian Platelets

• Mammalian platelets play a crucial role in responding to immediate tissue injury. They not only initiate coagulation – the clotting of blood – but also enable tissue repair and damage mitigation.
• Platelets achieve this by releasing presynthetized morphogens, cytokines, growth and chemotactic factors. These initiate the tissue regenerative, angiogenic (new blood vessel formation), and anti-inflammatory processes.

Concerns with Existing Biologic Products

• Blood-derived biologic products, such as Platelet-Rich Plasma (PRP) and Platelet Lysate (PL), are commonly used to support wound healing and tissue regeneration.
• However, these products have limitations. Not every desirable growth factor is released from the platelets, and additionally, the presence of plasma proteins like albumin, fibrinogen, complement, and immunoglobulins may pose increased risks of serum sickness or allergies.

Development of WEPLEX

• To tackle these issues, the researchers developed WEPLEX, a new platelet extract derived from equine blood platelets.
• This involves a process of concentrating and washing the platelets, followed by lysis using Triton X-114, a detergent.
• Unlike PRP, this product lacks albumin, fibrinogen, and immunoglobulins, which may provoke allergic responses.
• Interestingly, the platelet-derived growth factor content in WEPLEX is markedly higher than in PRP, enriching it by a factor of 266.

WEPLEX’s Advantages

• WEPLEX has the advantage of being able to undergo lyophilization i.e., freeze-drying, without losing its biological activity.
• Furthermore, WEPLEX was found to significantly inhibit both human and equine T cell proliferative responses to a plant-derived protein called phytohemagglutinin. This quality implies that it may have an immunosuppressive effect, which can be beneficial in managing inflammatory conditions.
• Also, WEPLEX seemed to divert murine (mouse) macrophages towards an IL-10 M2-like phenotype that exerts anti-inflammatory properties.
• Additionally, WEPLEX was shown to improve the outcome of a mouse model of colitis, an inflammatory bowel disease, suggesting its potential therapeutic application.

Conclusion

• The researchers put forth that WEPLEX, being sourced from equines, which are zoonosis-free (not transmitting diseases to humans), could serve as an effective and safe anti-inflammatory biological therapy for mammals across species.