Poly(ester amide) co-polymers promote blood and tissue compatibility

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Biodegradable poly(ester amide) (PEA) co-polymers are synthesized from alpha-amino acids.
• PEAs are being developed for biomedical applications, including device coatings and drug delivery systems.
• PEA coatings may enhance natural healing responses.

Purpose of the Study:

• To evaluate the blood and cellular compatibility of PEA co-polymers for cardiovascular stent coatings.
• To compare the in vitro responses to PEA with non-degradable and biodegradable polymers.
• To assess the potential of PEAs to promote a natural healing response.

Main Methods:

• In vitro assays were performed using representative elastomeric PEAs containing L-leucine and L-lysine.
• Monocyte inflammatory responses (IL-6, IL-1 beta, IL-1 receptor antagonist) were measured.
• Endothelial cell adhesion, spreading, and proliferation were assessed.
• Hemocompatibility was evaluated by measuring platelet and leukocyte depletion and adenosine triphosphate (ATP) release from platelets.

Main Results:

• PEA co-polymers significantly reduced pro-inflammatory cytokine secretion by monocytes while increasing anti-inflammatory mediator secretion.
• Endothelial cells adhered, spread, and proliferated on PEA, indicating good tissue compatibility.
• PEA demonstrated non-hemolytic properties and did not deplete platelets or leukocytes.
• Platelet activation on PEA was comparable to established compatible polymers like poly(lactic-co-glycolic acid).

Conclusions:

• Biodegradable, alpha-amino-acid-based PEAs exhibit favorable in vitro blood and tissue compatibility.
• These PEAs may support a natural healing response by modulating inflammation and promoting cell growth.
• PEA co-polymers show promise for cardiovascular applications and other biomedical uses requiring enhanced biocompatibility.