Regeneration of Autotransplanted Avascular Lymph Nodes in the Rat Is Improved by Platelet-Rich Plasma

Abstract

The aim of this study was to verify that subcutaneous lymph node transplantation inducing lymphatic regeneration is possible in healthy adult rats, in analogy to results obtained in other species. This rat model was used to determine the effects of lymph node fragmentation as well as sheep erythrocytes and platelet-rich plasma injection on the regeneration of the transplanted lymph nodes. The results show for the first time that the rat is an adequate model to study the regeneration of transplanted lymph nodes. Lymph node fragmentation seems to affect transplant regeneration negatively. An immune challenge by injection of sheep erythrocytes in the drainage area of the transplanted lymph nodes does not improve fragment regeneration. However, injection of syngeneic platelet-rich plasma containing several growth factors resulted in an improvement in regeneration. Lymph node fragment regeneration, although still experimental, could be relevant for lymphedema prevention. Acquired lymphedema has a high prevalence in developed countries as a consequence of the removal and/or radiotherapy of tumor-draining lymph nodes in cancer patients. This disease causes lifelong disability due to chronic swelling and increased risk of infections. It currently lacks an effective treatment.

Improved Regeneration of Autologous Transplanted Lymph Node Fragments by VEGF‐C Treatment

“…Thus, the effects of aging on lymph node regeneration will be important aspects for following studies. Hadamitzky et al (2009) documented an improvement in the regeneration of lymph node fragments after transplantation using platelet-rich plasma. Platelets can be seen as a pool of growth factors.…”

“…It had been documented that regeneration of avascular autotransplanted lymph nodes is possible in pig (Blum et al, 2007, rat , and sheep (Tobbia et al, 2009). The effects of a fragmentation of the lymph nodes before transplantation and stimulation of regeneration using platelet-rich plasma were analyzed in recent studies Hadamitzky et al, 2009), which showed that lymph node fragments are able to regenerate to lymph nodes in pig model and rat model. VEGF-C is an important growth factor in lymphangiogenesis (Alitalo et al, 2005;Blum and Pabst, 2006;Tervala et al, 2008).…”

Vascularized Lymph Node Transfer for Treatment of Lymphedema

“…11 PRP is shown to improve survival rate of transplanted lymph nodes while causing B-cell proliferation, which might aid in infection control. 12 The authors recommend a combination of surgical transplantation and synergistic growth factors in the treatment of lymphedema. 11,12 Another study showed that VLNT specimens had lower edema measures and lymphatic function significantly greater (P < 0.0001) with a healthier appearance compared with avascular and control specimens.…”

“…12 The authors recommend a combination of surgical transplantation and synergistic growth factors in the treatment of lymphedema. 11,12 Another study showed that VLNT specimens had lower edema measures and lymphatic function significantly greater (P < 0.0001) with a healthier appearance compared with avascular and control specimens. 13 Fragmented lymph node transfers were studied, and the protective effect against development of dermal backflow was observed.…”

“…14 In addition, a more wholly preserved nodal transplant proved beneficial according to regeneration patterns. 12,14 Timing of VLNT has been shown and affect outcomes, as seen in success rates being higher in immediate versus delayed transplants. 9…”