Introduction
Developing transplantable humanized endocrine grafts for long-term management of disorders like uncontrolled diabetes mellitus has been one of the most challenging concerns in tissue and organ bioengineering. Hence, we aimed to develop bio/immune compatible and transplantable humanized insulin producing neo-organs through biofabrication of rat spleen which acts as secondary neo-organoid after ectopic transplantation.
Methods
An efficient process was developed using splenic artery perfusion to generate completely cell deficient decellularized splenic matrices (DSM). Microscopic, vascular tree imaging, mechanical strength and other required analysis were performed before and after decellularization. Biofabrication of humanized insulin producing neo-organ was performed through infusion of hyperglycaemic challenged trans-differentiated human hepatic progenitor cells (hHPCs) in DSM. Intra-peritoneal transplantation of biofabricated insulin producing humanized neo-organs in rats was done to evaluate the bio/immune compatibility.
Results
The biofabrication strategy generated highly intact DSM with preserved organ architecture, extracellular matrix and organ vasculature. Repopulation of DSM with glucose responsive cells showed enhanced engraftment efficiency, survival and proliferation. Bioengineered humanized insulin producing neo-organs showed higher amount of insulin secretion than conventional 2D-cultured cells in response to hyperglycaemic stimuli ex vivo. Glucose responsive humanized neo-organs survived in vivo without eliciting immunological or fibrotic responses and proved to be secondary neo-organoids at ectopic site with the development of neo-vasculature and responded to hyperglycaemic challenge.
Conclusion
The present study provides first proof-of-concept for biofabricating bio/immune compatible, humanized insulin producing neo-organoids post-ectopic transplantation which provides more suitable functional biological implants for long-term management of uncontrolled diabetes mellitus.