Accelerated Wound Healing in Minipigs by On-Site Production and Delivery of CXCL12 by Transformed Lactic Acid Bacteria

Abstract

Non-healing wounds are a growing medical problem and result in considerable suffering. The lack of pharmaceutical treatment options reflects the multistep wound healing process, and the complexity of both translation and assessment of treatment efficacy. We previously demonstrated accelerated healing of full-thickness wounds in mice following topical application of the probiotic bacteria Limosilactobacillus reuteri R2LC transformed to express CXCL12. In this study, safety and biological effects of a freeze-dried formulation of CXCL12-producing L. reuteri (ILP100) were investigated in induced full-thickness wounds in minipigs, and different wound healing evaluation methods (macroscopic, planimetry, 2D-photographs, 3D-scanning, ultrasound) were compared. We found that treatment with ILP100 was safe and accelerated healing, as granulation tissue filled wound cavities 1 day faster in treated compared to untreated/placebo-treated wounds. Furthermore, evaluation using planimetry resulted in 1.5 days faster healing than using 2D photographs of the same wounds, whereas the areas measured using 2D photographs were smaller compared to those obtained from 3D scans accounting for surface curvatures, whereas ultrasound imaging enabled detailed detection of thin epithelial layers. In conclusion, topical administration of the drug candidate ILP100 warrants further clinical development as it was proven to be safe and to accelerate healing using different evaluation methods in minipigs.

The chemokines CXCL8 and CXCL12: molecular and functional properties, role in disease and efforts towards pharmacological intervention

“…These bacteria have the additional and essential advantage that in the acidic environment CXCL12 is protected from CD26 proteolytic inactivation [ 287 ]. Recently, this method was found to be safe and accelerated healing using different evaluation methods in minipigs [ 288 ]. Over the last years, different research groups started investigating the use of hydrogels or scaffolds loaded with CXCL12 for local delivery of this chemokine to promote injury repair, wound healing, bone repair, and for cancer treatment.…”

Live Biotherapeutics : importance of formulation and lyophilization parametersand an example of a clinical application

“…Tolerability, clinical and biologic effects were assessed at each visit (SAD: Day 1, 2, 3, 7, 14, and at 6 weeks, 3 months and 12 months from start of treatment at Day 1; MAD: Day 1,2,3,5,8,10,12,15,17,19,21,32, and at 6 weeks, 3 months and 12 months after last dose at Day 19). All assessments were blinded and occurred by on-site visual inspections of the wounds by the Principal Investigator (or co-investigator), as well as off-site by traceable evaluation and detailed wound area measurements from 2D photographs of all wounds by 3 Independent Evaluators (IEs) with expertise in wound healing.…”

“…11 Accelerated healing after topical delivery has been well-documented in multiple non-clinical studies, depends on increased numbers of wound macrophages of a restorative phenotype expressing TGF-β, and a favourable safety profile was demonstrated. 5,12 Here, we present results from the randomised, blinded, and placebo-controlled first-in-human study designed to primarily assess safety and tolerability of ILP100-Topical, whereas the secondary and exploratory objectives aimed to evaluate clinical and biologic effects on wound healing. To complement and validate the conventional assessments performed by Investigators during visits, blinded and highresolution wound imaging techniques were used, which provided objective analyses of healing in fully traceable and reproducible data sets.…”

Biofilm therapy for chronic wounds

“…97 In addition to its ability to inhibit biofilm formation, the probiotic Lactobacillus rhamnosus lysate also promoted wound epithelialization by enhancing proliferation and migration of keratin-forming cells. Using Lactobacillus as a carrier for the local delivery of chemokine CXCL12 to mouse, minipig and human skin wound models, 98,99 lactic acid produced by the bacteria lowered the pH of the wounds and enhanced the action and bioavailability of CXCL12, which in turn enhanced the proliferation of the host cells. The potential mechanism may be related to the increased expression of chemokine CXCL2 and its receptor.…”