Vascularized tissue engineering mouse chamber model supports thymopoiesis of ectopic thymus tissue grafts.

We have previously established a chamber model of tissue engineering that promotes de novo angiogenesis and vascularization of engrafted cells and tissues when combined with an extracellular matrix. Here we demonstrate that the mouse chamber (MC) model can sustain ectopic grafts of murine fetal thymus lobes and, to a limited degree, human pediatric thymus tissue, resulting in de novo T-cell production. Silicone chambers containing Matrigel® and thymus tissues were placed around exposed epigastric vessels and the ends sealed with bone wax, before implantation into the inguinal fat pad of athymic Balb/cnu/nu (nude) mice. Murine, embryonic day 15 (E15) thymus grafts were found to be well vascularized and viable within the MC upon harvest at week 11. In contrast, engraftment of both adult murine and pediatric human thymus tissue was limited, with only one out of the seven human thymus grafts sustaining mature, murine-derived T-cell development. Increased CD4+ and CD8+ T-cell numbers were observed in the perip...