Scaffold Seeding Conditions and Meniscal Repair in an Experimental Model

INTRODUCTION: The meniscus is vascularized only in the outer third and lesions occurring in the inner two-thirds heal poorly or not at all. Treatment for these types of lesions commonly involves partial meniscectomy, which can lead to long-term joint degeneration. A cellbased tissue-engineered construct can be employed for treating lesions occurring in the avascular inner zone of the knee meniscus [1-3]. In a pilot study, we have demonstrated healing of a meniscal lesion in a heterotopic in vivo mouse model using articular chondrocytes-seeded devitalized meniscus [1]. Woven Vicryl mesh (PLGA, Ethicon) is a biocompatible and biodegradable synthetic polymer used for abdominal wall defect closure or pelvic floor repair. This FDA approved material can be employed as a scaffold for meniscal repair because it is thin and flexible enough to interpose into the tear lesions. Recently, we developed a dynamic cellseeding technique and a meniscus novel in vivo mouse model using a three-layered construct (chondrocyte-seeded PLGA mesh between discs) to assess the meniscal repair capacity of the scaffolds [2, 3]. The aims of this study were: 1) to assess the seeding and culture conditions (static and dynamic) for the scaffolds; 2) to assess the healing capacity of the cell-seeded scaffolds in a meniscal repair model; and 3) to assess in vivo cell labeling for tracking cells during the reparative process.