Angiogenic biomarkers and healing of living cellular constructs

Abstract

The use of intra-oral soft-tissue-engineered devices has demonstrated potential for oral mucosa regeneration. The aim of this study was to investigate the temporal expression of angiogenic biomarkers during wound healing of soft tissue reconstructive procedures comparing living cellular constructs (LCC) with autogenous free gingival grafts. Forty-four human participants bilaterally lacking sufficient zones of attached keratinized gingiva were randomly assigned to soft tissue surgery plus either LCC or autograft. Wound fluid samples were collected at baseline and weeks 1, 2, 3, and 4 post-operatively and analyzed for a panel of angiogenic biomarkers: angiogenin (ANG), angiostatin (ANT), PDGF-BB, VEGF, FGF-2, IL-8, TIMP-1, TIMP-2, GM-CSF, and IP-10. Results demonstrated a significant increase in expression of ANT, PDGF-BB, VEGF, FGF-2, and IL-8 for the LCC group over the autograft group at the early stages of wound repair. Although angiogenic biomarkers were modestly elevated for the LCC group, no clinical correlation with wound healing was found. This human investigation demonstrates that, during early wound-healing events, expression of angiogenic-related biomarkers is up-regulated in sites treated with LCC compared with autogenous free gingival grafts, which may provide a safe and effective alternative for regenerating intra-oral soft tissues (ClinicalTrials.gov number, NCT01134081).

Figures

Figure 1.

Patient distribution, time line, and living cellular construct transplantation. (A) Stratification of the study population was divided into 2 treatment groups at 3 clinical centers. (B) Study timeline. GCF, gingival crevicular fluid; WF, wound fluid; CWHS, clinical wound-healing score. (C) Sealed bioreactor with living cellular construct; (D) living cellular construct placed at the surgical site, 254 x 169 mm (300 x 300 DPI).

Figure 2.

Wound fluid collection at the borders of the wound during the 4 wks post-operatively for both autograft and living cellular construct. 156 x 179 mm (300 x 300 DPI).

Figure 3.

Expression of angiogenic biomarkers of living cellular construct (LCC) and autograft from baseline to week 4. (A) Mean expression of VEGF. Inter-group analysis (*) demonstrated a statistically significant expression of VEGF for living cellular constructs at week 1 (p < 0.05). (B) Mean expression of ANG. (C) Mean expression of IL-8. Inter-group analysis (*) demonstrated a statistically significant expression for living cellular constructs at week 1 (p < 0.05). (D) Mean expression of FGF-2. Inter-group analysis (*) demonstrated a statistically significant expression for living cellular constructs at week 1 (p < 0.05). (E) Mean expression of PDGF-BB. Inter-group analysis (*) demonstrated a statistically significant expression for living cellular constructs at week 1 (p < 0.05). (F) Mean expression of ANT. Inter-group analysis (*) demonstrated a statistically significant difference in the expression for living cellular constructs at week 1 (p < 0.05). (G) Mean expression of TIMP-1. (H) Mean expression of TIMP-2. Bars indicate standard error measurements (SEM). 319 x 374 mm (300 x 300 DPI).