Electrospun fibers in veterinary applications

Electrospun fibers have been investigated for clinical applications over the last decade and medical devices based on it are now available for clinical usage. Beyond human clinical applications, some investigators are looking at it for veterinary applications. Many in vivo studies on electrospun scaffold are already carried out in domestic animals such as pig, dogs and even horses for the eventual translation into human clinical trial. Such in vivo studies have already provided evidence that electrospun fibers may be used in treatment for animals [Wu et al 2015, Holderegger et al 2015].

One of the main uses for electrospun fibers is for carrying drugs or other active compounds. Souza et al (2014) investigated the use of a biodegradable electrospun fiber made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) for encapsulation and release of diclofenac sodium, a drug recommended for human and animal use in cases of pain, fever, and inflammation. PHBV fibers were loaded with up to 20% of the drug without any beads formation. Karuppannan et al (2017) investigated the use of electrospun zein fibers as a progesterone delivery vehicle for estrus synchronization of bovines. Progesterone was dissolved in the solution zein prior to electrospinning. In vitro release of progesterone in PBS showed a gradual release rate in the seven days of study. Vero cells cultured on the progesterone loaded zein fibers were also found to remain mostly viable after 24 hours.

Scaffold made from electrospun fibers have a thickness that creates a 3D environment similar to native tissue. This allows researchers to explore the use of electrospun fibers for modeling tissue function in vitro. MacKintosh et al (2015) used electrospun polyglycolide (PGA) fiber scaffold to construct a functional reconstitution of bovine endometrium with seeded epithelial and stromal cells. The stromal cells were first seeded into the scaffold followed by the epithelial cells either 1 day or 7 days later. In their study, epithelial cells seeded 1 day after stromal cells were seeded was more representative of native endometrial tissue on day 10 compared epithelial cells seeded on day 7. This could be due to biochemical cue from the epithelial cells influencing the behavior and proliferation of the stromal cells. The co-cultured epithelial and stromal cells on the scaffold showed appropriate expression of cytokeratin and vimentin of native endometrium and ZO-1 by epithelial cells. Functionality of the construct was also demonstrated by prostaglandin E₂ (PGE) and F_2α (PGF) responsiveness of endometrial cells to oxytocin plus arachidonic acid and lipopolysaccharide.