Use of a latex biomembrane for bladder augmentation in a rabbit model: biocompatibility, clinical and histological outcomes

Abstract

Purpose: To investigate histological features and biocompatibility of a latex biomembrane for bladder augmentation using a rabbit model. Material and Methods: After a partial cystectomy, a patch of a non-vulcanized latex biomembrane (2x4 cm) was sewn at 15, 45 and 90 days after surgery and the bladder was removed. The 5-μm preparations obtained from grafted area and normal bladder were stained with hematoxylin-eosin. Immunohistochemical staining was performed with a primary antibody against alpha-actin to assess muscle regeneration. Results: No death, urinary leakage or graft extrusion occurred in any group. All bladders showed a spherical shape. Macbladder. A bladder stone was found in one animal (6.6%). On the 90th day, histology revealed continuity of transitional epithelium of host bladder tissue on the patch area. At this time, the muscle layers were well organized in a similar fashion days -p < 0.0001, 45 days -p < 0.001, and 90 days -p < 0.01. The anti alpha-actin immunoexpression peaked at 45 days, when the graft was observed covered by muscle cells. Conclusion:The latex biomembrane is biocompatible and can be used in models for bladder augmentation in rabbits. It promotes epithelium and muscle regeneration without urinary leakage.

Expression of VEGF and collagen using a latex biomembrane as bladder replacement in rabbits

“…On this basis, we confirmed the angiogenic potential of the membrane and demonstrated that the process is temporary, accompanying the reduction of the inflammatory process, important events for the lack of perpetuation of inadequate tissue response to the graft used. An explanation for this phenomenon could be the intense macrophage activity during the early phases of scarring (9), supporting the statement that these cells play a controlling role in fibroblast proliferation and migration, in matrix formation, and in angiogenesis (21,22).…”

“…Previous experimental studies with the latex biomembrane have shown that it allows the ingrowth of muscle cells and induces a temporary inflammatory response, mainly a TH2 lymphocyte immune response (9). The ideal material for bladder replacement or enlargement should allow the progressive growth of all components of the normal bladder wall preserving their mechanical and functional properties (7,10).…”

“…Matrix preparation followed a previously published technique (8,9). The animals were anesthetized with an intramuscular injection of ketamine (35 mg/kg) and xylazine (5 mg/kg).…”

“…A partial cystectomy (4.0 cm2 -2.0 x 2.0 cm) was performed through a median laparotomy. A latex biomembrane patch of the same area was grafted to the remaining host bladder with continuous 5/0 monofilament absorbable polydioxanone sulfate suture as described in our previous study (9). After surgery, enrofloxacyn (9 mg/kg) was administered subcutaneously to all animals daily for 2 days.…”

“…Previous experimental studies with the natural latex biomembrane have proved that it is a biodegradable material of easy preparation and handling, encouraging tissue neoformation (8,9). On this basis, we were interested in investigating collagen development and angiogenesis using this latex graft.…”