Decellularized lymph node scaffolds accelerate restoration of lymphatic drainage in rat hind limb lymphedema.

Background: There is a lack of effective lymphedema prevention methods. The objective of this study was to investigate the ability of decellularized lymph nodes (dLNs) transplantation to prevent hindlimb lymphedema. Methods: Porcine dLNs were prepared using 1% sodium dodecyl sulfate and 1% Triton X-100, and the effectiveness of decellularization was assessed by histological assessment and DNA quantification. Lymph node (LN) fragments and dLNs were transplanted into mice, and samples were collected for evaluating biocompatibility at the fourth week postsurgery. Thirty-six SD rats were separated into a control group (lymphatic dissection), a dLNs group (lymphatic dissection and dLNs transplant) and a sham group (inguinal skin circumferentially incised). Hindlimb circumference was monitored every 3 days. Indocyanine green lymphography was performed before and every week after surgery. Samples were collected for histological assessment at the second and fourth weeks. Results: The dLNs showed virtually complete absence of cellular material, maintenance of spatial structures, and good biocompatibility and induced immune cell infiltration. Compared with that of the control group, the average hindlimb circumference of the dLN group was significantly reduced on postoperative days (PODs) 8, 12, and 16, and that of the sham group was significantly reduced on PODs 4, 8, 12, 16, and 20. The sham group exhibited intact inguinal LNs and lymphatic drainage. Neonatal lymphatic vessels (LVs) were observed in the dLN group, and obvious dermal backflow was observed in the control group. Transplanted dLNs induced the infiltration of immune cells, which subsequently integrated into the preexisting lymphatic system. Compared with those in the control group or sham group, the number of LYVE-1+ LVs in the affected limb was greater in the dLN group. Conclusion: The dLNs scaffolds induced the infiltration of immune cells and promoted LVs regeneration, which integrated into the preexisting lymphatic system to accelerate the restoration of lymphatic drainage.