Seeding cell approach for tissue-engineered urethral reconstruction in animal study: A systematic review and meta-analysis

Abstract

We systematically reviewed published preclinical studies to evaluate the effectiveness of cell-seeded tissue engineering approach for urethral reconstruction in an animal model. The outcomes were summarized by success factors in the animal experiments, which evaluate the possibility and feasibility of a clinical application in the future. Preclinical studies of tissue engineering approaches for urethral reconstruction were identified through a systematic search in PubMed, Embase, and Biosis Previews (web of science SP) databases for studies published from 1 January 1980 to 23 November 2014. Primary studies were included if urethral reconstruction was performed using a tissue-engineered biomaterial in any animal species (with the experiment group being a cell-seeded scaffold and the control group being a cell-free scaffold) with histology and urethrography as the outcome measure. A total of 15 preclinical studies were included in our meta-analysis. The histology and urethrography outcome between the experimental and control groups were considered to be the most clinically relevant. Through this systematic approach, our outcomes suggested that applying the cell-seeded biomaterial in creating a neo-urethra was stable and effective. And multi-type cells including epithelial cells as well as smooth muscle cells or fibroblasts seemed to be a better strategy. Stem cells, especially after epithelial differentiation, could be a promising choice for future researches.

Keywords: Tissue engineering; animal model; cell-seeded/unseeded biomaterial; meta-analysis; urethral defect; urethral reconstruction.

Figure 1

Flow chart of the study selection process. (A color version of this figure is available in the online journal.)

Figure 2

Forest plot of RRs with 95% CIs for cell-seeded biomaterials and their effect on urethral reconstruction. The center of each square represents the RRs, the area of the square is the number of samples and thus the weight used in the meta-analysis and the horizontal line indicates the 95%CI

Figure 3

Forest plot of RRs with 95% CIs for the effect of two cell types and one cell type. (A color version of this figure is available in the online journal.)

Figure 4

Funnel plots (a: Begg's test; b: Egger’s test) Log (OR)/the standard error of log (OR) and MD/the standard error of MD were adopted to yield funnel plots