Polypropylene mesh for hernia repair with controllable cell adhesion/de-adhesion properties

Abstract

Herein, a versatile bilayer system, composed by a polypropylene (PP) mesh and a covalently bonded poly(N-isopropylacrylamide) (PNIPAAm) hydrogel, is reported. The cell adhesion mechanism was successfully modulated by controlling the architecture of the hydrogel in terms of duration of PNIPAAm grafting time, crosslinker content, and temperature of material exposure in PBS solutions (below and above the LCST of PNIPAAm). The best in vitro results with fibroblast (COS-1) and epithelial (MCF-7) cells was obtained with a mesh modified with a porous iPP-g-PNIPAAm bilayer system, prepared via PNIPAAm grafting for 2 h at the lowest N,N 0 -methylene bis(acrylamide) (MBA) concentration (1 mM). Under these conditions, the detachment of the fibroblast-like cells was 50% lower than that of the control, after 7 days of cell incubation, which represents a high de-adhesion of cells in a short period. Moreover, the whole system showed excellent stability in dry or wet media, proving that the thermosensitive hydrogel was well adhered to the polymer surface, after PP fibre activation by cold plasma. This study provides new insights on the development of anti-adherent meshes for abdominal hernia repair.

Toward the New Generation of Surgical Meshes with 4D Response: Soft, Dynamic, and Adaptable

“…The preparation of the bilayer PP‐ g ‐PNIPAAm mesh was already explained in our previous works. [ 27,28 ] However, in the case of the monolayer design, that was not reported before, the grafting reaction is preceded by a curl up of the untreated mesh around a glass bar support, allowing to obtain the desired shape (rolled) and avoiding the deposition of the gel on the inner side of the mesh (Figure 1b1–b2). The sample preparation was detailed in the Section 4.2.…”

“…Up to now, there are no other studies on PNIPAAm‐based textiles fabricated, upon plasma activation, than those reported by our group. [ 27,28 ] Frequently, investigations are related to PNIPAAm derivatives for soft robotics [ 23,28,30,31,38 ] and microactuator devices, [ 30,39,40 ] the latter ones being composed of combinations of various soft hydrogels. Moreover, there have been few attempts towards in situ detection of the effect of temperature and humidity in the 4D response of thermosensitive materials.…”

“…Such platform is supposed to be unsuitable for mesh implants because it cannot ensure the growth of cells across the mesh that would reduce the graft integration in the tissue. [ 28 ] The unfolding experiments for this system are reported in Figure S4, (Supporting Information).…”

“…In this context, the best in vitro results with fibroblast (COS‐1) and epithelial (MCF‐7) cells were obtained with a lightweight mesh substrate modified with a porous iPP‐ g ‐PNIPAAm bilayer system, prepared via PNIPAAm grafting for 2 h and with the lowest crosslinker content. [ 28 ] The cell attachment is desirable to prove the biocompatibility of the new device, whereas the phenomena of deadhesion is very appealing for the final application of the mesh, in order to obtain a material able to avoid adherence to viscera.…”

In vivo soft tissue reinforcement with bacterial nanocellulose

“…glueing). 7,8 Besides, multi-component grafts have been advocated as a well-suited strategy to isolate the PP mesh from the viscera by adding an additional layer of a synthetic 9,10 or natural biomaterial 11,12 that acts as an anti-adherent barrier. Despite recent advances, clinicians and manufacturers are still pursuing an optimal mesh to improve the clinical outcome and the costeffectiveness ratio of hernioplasty procedures by leveraging the selection of materials, porous structure, mechanical resistance, anti-adhesive properties, biocompatibility, long term mechanical stability, tissue integration and conformability.…”