Retrospective Evaluation of Progenitor Biological Bandage Use: A Complementary and Safe Therapeutic Management Option for Prevention of Hypertrophic Scarring in Pediatric Burn Care

Abstract

Progenitor Biological Bandages (PBB) have been continuously applied clinically in the Lausanne Burn Center for over two decades. Vast translational experience and hindsight have been gathered, specifically for cutaneous healing promotion of donor-site grafts and second-degree pediatric burns. PBBs constitute combined Advanced Therapy Medicinal Products, containing viable cultured allogeneic fetal dermal progenitor fibroblasts. Such constructs may partly favor repair and regeneration of functional cutaneous tissues by releasing cytokines and growth factors, potentially negating the need for subsequent skin grafting, while reducing the formation of hypertrophic scar tissues. This retrospective case-control study (2010–2018) of pediatric second-degree burn patients comprehensively compared two initial wound treatment options (i.e., PBBs versus Aquacel® Ag, applied during ten to twelve days post-trauma). Results confirmed clinical safety of PBBs with regard to morbidity, mortality, and overall complications. No difference was detected between groups for length of hospitalization or initial relative burn surface decreasing rates. Nevertheless, a trend was observed in younger patients treated with PBBs, requiring fewer corrective interventions or subsequent skin grafting. Importantly, significant improvements were observed in the PBB group regarding hypertrophic scarring (i.e., reduced number of scar complications and related corrective interventions). Such results establish evidence of clinical benefits yielded by the Swiss fetal progenitor cell transplantation program and favor further implementation of specific cell therapies in highly specialized regenerative medicine.

Evolution of Diploid Progenitor Lung Cell Applications: From Optimized Biotechnological Substrates to Potential Active Pharmaceutical Ingredients in Respiratory Tract Regenerative Medicine

“…In particular, based on the large available data on human diploid progenitor cell GMP banking in Switzerland for therapeutic material sourcing, high interest is currently set locally on specific cell types (i.e., FE002-Lu lung diploid progenitor cell types) for candidacy as novel and robust cell source establishment [25]. Indeed, specific requirements for biological material sourcing, cell type establishment, and cell banking have already been met for FE002 diploid cell types for use thereof as active pharmaceutical ingredients, showing strong overlaps with the requirements set forth for vaccine substrates [31][32][33][42][43][44][45][55][56][57]. To illustrate these parallels, a comparative analysis of MRC-5 cells and FE002-Lu cells was performed and summarized (Figure 5).…”

“…Various musculoskeletal and related soft-tissue diploid progenitor cell types have been studied over the past two decades, and dermal cells (i.e., FE002-SK2 cell types) have been successfully implemented in clinical use [25,26,33]. Most of the local experience has been generated around cutaneous tissue reconstruction and/or regeneration, with progenitor cells being specifically applied as an API for the management of pediatric burns (i.e., second-degree thermal wounds and related graft donor-sites) and acute or chronic inflammatory cutaneous wounds (i.e., lacerations and refractory geriatric lower-limb ulcers) [36,39,41,43,44]. To treat these skin conditions and wounds over the past twenty years, viable progenitor cells were formulated in collagen scaffolds to form progenitor biological bandages (PBB).…”

“…The most notable effects of PBB applications have been the reduced tissue scarring following recovery, with excellent structural and functional skin barrier restoration [33,44]. Additionally, reduced pain and inflammation have been observed upon application of PBBs, albeit without standardized and controlled documentation [44].…”

“…The most notable effects of PBB applications have been the reduced tissue scarring following recovery, with excellent structural and functional skin barrier restoration [33,44]. Additionally, reduced pain and inflammation have been observed upon application of PBBs, albeit without standardized and controlled documentation [44]. Therefore, based on translational experience around such biologicals, cell therapy approaches for the management of inflammatory lung diseases or affections and related symptoms (e.g., COVID-19 patients and burn patient severe inhalation syndrome) using local homologous allogeneic cell-based or cell-derived product administrations are considered.…”

“…Most importantly, and in addition to the considerable inherent technical advantages of such cellular materials, a vast therapeutic potential exists for the use of diploid progenitor cells or cell derivatives for application in allogeneic regenerative medicine [27][28][29][30][31][32]. Indeed, skin-derived diploid progenitor cell sources have been extensively studied and clinically applied, in particular for the therapeutic management of pediatric burns and chronic inflammatory cutaneous wounds [33][34][35][36][37][38][39][40][41][42][43][44].…”