Regenerative Engineering: Current Applications and Future Perspectives

Many pathologies, congenital defects, and traumatic injuries are untreatable by conventional pharmacologic or surgical interventions. Regenerative engineering represents an ever-growing interdisciplinary field aimed at creating biological replacements for injured tissues and dysfunctional organs. The need for bioengineered replacement parts is ubiquitous among all surgical disciplines. However, to date, clinical translation has been limited to thin, small, and/or acellular structures. Development of thicker tissues continues to be limited by vascularization and other impediments. Nevertheless, currently available materials, methods, and technologies serve as robust platforms for more complex tissue fabrication in the future. This review article highlights the current methodologies, clinical achievements, tenacious barriers, and future perspectives of regenerative engineering.

Employing Extracellular Matrix-Based Tissue Engineering Strategies for Age-Dependent Tissue Degenerations

Tissues and organs are not composed of solely cellular components; instead, they converge with an extracellular matrix (ECM). The composition and function of the ECM differ depending on tissue types. The ECM provides a microenvironment that is essential for cellular functionality and regulation. However, during aging, the ECM undergoes significant changes along with the cellular components. The ECM constituents are over- or down-expressed, degraded, and deformed in senescence cells. ECM aging contributes to tissue dysfunction and failure of stem cell maintenance. Aging is the primary risk factor for prevalent diseases, and ECM aging is directly or indirectly correlated to it. Hence, rejuvenation strategies are necessitated to treat various age-associated symptoms. Recent rejuvenation strategies focus on the ECM as the basic biomaterial for regenerative therapies, such as tissue engineering. Modified and decellularized ECMs can be used to substitute aged ECMs and cell niches for culturing engineered tissues. Various tissue engineering approaches, including three-dimensional bioprinting, enable cell delivery and the fabrication of transplantable engineered tissues by employing ECM-based biomaterials.

The molecular profile of the inflammatory process differs among various neurodevelopmental disorders with or without cognitive component: A hypothesis of persistent systemic dysfunction and hyper-resolution

Introduction

Challenges of diverse origin in childhood can alter the growth and development of the central nervous system, affecting structures and functions. As a consequence of the damage suffered during the perinatal period, long periods of dysfunctionality may occur, such as regulatory disorders, which may result in remaining in a process of low-grade inflammation. We previously found that perinatal risks and neurological signs are associated with long-term changes in circulating concentrations of molecules of the inflammatory process, findings that are consistent with the postulate that long periods of dysfunction may condition long-lasting low-grade inflammation or parainflammation. The aim of this study was to assess whether different expressions of neurological disorders show variations in their inflammatory molecule profiles or whether there is a common pattern.

Methods

We included screening for (a) caregiver-perceived risk detection of regulatory disturbances, using the DeGangi instrument; (b) dysautonomia or asymmetries, through neurodevelopmental assessments; (c) cognitive developmental disturbances (using the Bailey instrument). We assessed protein molecules on a multiplex system, and lipid molecules by ELISA.

Results

We found a similar, although not identical, pattern of cytokine profiles with the presence of risk of regulatory disturbances, dysautonomia and asymmetries; but an opposite inflammatory profile was associated with cognitive impairment.

Discussion

Our results suggest that there are diverse, probably limited, molecular footprints associated with impaired function, and that these footprints may depend on the response requirements necessary to adjust to the altered internal environment. Here we propose a theoretical model that suggests possible scenarios for inflammatory outcomes associated with chronic challenges.