Engineering vascularized adipose tissue using microvascular fragments in fibrin hydrogels

Statement of Purpose: Current therapies for soft tissue defects caused by numerous pathologies and trauma include autologous grafting and commercially available fillers. However, these treatment methods present several challenges and limitations, such as donor-site morbidity and volume loss over time. Even though bioactive constructs that can regenerate adipose tissue have been tissue engineered, translatable approaches require that the adipose tissue be vascularized to meet the significant dimension required for clinical tissue defects.¹ Microvascular fragments (MVFs), a collection of arterioles, venules, and capillaries derived from adipose tissue, are known for their ability to form extensive vascular networks², however due to their native multicellular properties we hypothesize MVFs could also serve as a source of adipocytes to support adipose tissue formation. Therefore, the objective of this study was to engineer adipose tissue using a fibrin-based hydrogel with MVFs as a single source of both vascularization and adipocytes. Our objectives were to (1) determine the adipogenic potential of MVFs in fibrin and (2) determine if the angiogenic potential of MVFs can be maintained during adipogenic differentiation.