The Host Immune Response to Tissue-Engineered Organs: Current Problems and Future Directions

Abstract

As the global health burden of chronic disease increases, end-stage organ failure has become a costly and intractable problem. De novo organ creation is one of the long-term goals of the medical community. One of the promising avenues is that of tissue engineering: the use of biomaterials to create cells, structures, or even whole organs. Tissue engineering has emerged from its nascent stage, with several proof-of-principle trials performed across various tissue types. As tissue engineering moves from the realm of case trials to broader clinical study, three major questions have emerged: (1) Can the production of biological scaffolds be scaled up accordingly to meet current and future demands without generating an unfavorable immune response? (2) Are biological scaffolds plus or minus the inclusion of cells replaced by scar tissue or native functional tissue? (3) Can tissue-engineered organs be grown in children and adolescents given the different immune profiles of children? In this review, we highlight current research in the immunological response to tissue-engineered biomaterials, cells, and whole organs and address the answers to these questions.

Current perspectives on biological approaches for osteoarthritis

“…Several promising synthetic options also exist, such as glass–ceramic, hydroxyapatite, fibronectin, alginate, and biphasic calcium phosphate, which reduce the risk of an immunological response but may lack material properties and factors native to human bone, which would reduce their efficacy as scaffolds. There is continued effort to design an implantable natural or synthetic scaffold with stem cells or bioactive factors that modulates a subsequent immunological response that consists of native‐like biological materials to regenerate bony defects …”

“…There is continued effort to design an implantable natural or synthetic scaffold with stem cells or bioactive factors that modulates a subsequent immunological response that consists of native-like biological materials to regenerate bony defects. 205,206 Nanotechnology, 3D bioprinting, and rapid prototyping A material with a grain size of less than 100 nm is defined as a nanomaterial. Most biological molecules (e.g., proteins, enzymes, and nucleic acids) have similar dimensions and properties to nanomolecules, and therefore their biological behavior is closely related.…”

Whole-Organ Tissue Engineering: No Longer Just a Dream

“…The host immune response can profoundly impact the functionality and durability of the allograft [88].…”

The sustained release of basic fibroblast growth factor accelerates angiogenesis and the survival of the inactivated dermis by high hydrostatic pressure

“…Recently, a number of different decellularization methods, including chemical, biological and physical and miscellaneous agents, have been suggested to be useful for generating superior bioengineering tissue [13]. Decellularized tissue retains its native structure or mechanical properties and has been reported to show low or no immunogenicity [14, 15], making it an ideal substitute or scaffold for tissue engineering and regenerative medicine. High hydrostatic pressure (HHP), another potential new decellularization method, is a physical technique that can inactivate cells or tissues in a short time without using any chemical reagents [16–20].…”