Engineered multilayer ovarian tissue that secretes sex steroids and peptide hormones in response to gonadotropins

Abstract

Although hormone replacement therapy is an option for the loss of ovarian function, hormone delivery through pharmacological means results in various clinical complications. The present study was designed to deliver sex steroids by a functional construct fabricated using encapsulation techniques. Theca and granulosa cells isolated from ovaries of 21-day old rats were encapsulated in multilayer alginate microcapsules to recapitulate the native follicular structure. Cells encapsulated in two other schemes were used as controls to assess the importance of the multilayer structure. The endocrine functions of the encapsulated cells were assessed in vitro for a period of 30 days. Encapsulated cells showed sustained viability during long-term in vitro culture with those encapsulated in multilayer capsules secreting significantly higher and sustained concentrations of 17 β-estradiol (E2) than the two other encapsulation schemes (p<0.05, n=6) in response to follicle-stimulating hormone (FSH) and luteinizing hormone (LH). In addition, cells in the multilayer microcapsules also secreted activin and inhibin in vitro. In contrast, when granulosa and theca cells were cultured in 2-D culture, progesterone (P4) secretion increased while E2 secretion decreased over a 30-day period. In summary, we have designed a multilayer engineered ovarian tissue that secretes sex steroids and peptide hormones and responds to gonadotropins, thus demonstrating the ability to recapitulate native ovarian structure ex vivo.

Bioengineering the Ovarian Follicle Microenvironment

“…Several approaches to develop modular ovarian components are under way. Theca and granulosa cells encapsulated in multilayer alginate capsules respond to gonadotropins and secrete sex hormones, which is similar to what occurs in an intact follicle (106). This multilayered engineered ovarian tissue could be applied to treat the loss of ovarian function by providing physiological serum levels of hormones in response to gonadotropins.…”

Plasticity of granulosa cells: on the crossroad of stemness and transdifferentiation potential

“…This limitation could be overcome with isolating and transplanting less differentiated subpopulation of GCs which has not yet undergone luteinization. On the other side, Sittadjody et al [69] constructed multilayered microcapsule with encapsulated theca cells and GCs from rats to recapitulate the follicular structure. They assessed microcapsules in vitro and demonstrated high viability of encapsulated cells which secreted sex steroids and peptide hormones.…”

The Pharmacology of Regenerative Medicine

“…Recently, we demonstrated the importance of the architecture in a tissue engineered ovary through more native-like cell-cell interactions. Through the proper orientation of granulosa and theca cells in an alginate material, more physiologically relevant levels of estrogen and progesterone were produced (Sittadjody et al, 2013).…”