Plastic Surgery Research Council
Members Only  |  Contact  |  PSRC on Facebook
PSRC 60th Annual Meeting
Program and Abstracts

Back to 2015 Annual Meeting Program


Lymph Node Transfer Restores Immune Responses in a Mouse Model of Lymphedema
Walter J. Joseph, III, BS, Seth Z. Aschen, BS, Daniel A. Cuzzone, MD, Jason C. Gardenier, MD, Swapna Ghanta, MD, Nicholas J. Albano, BS, Ira L. Savetsky, MD, Jeremy S. Torrisi, BA, Babak J. Mehrara, MD.
MSKCC, New York, NY, USA.

PURPOSE: Lymphedema is a common condition affecting as many as 1 in 3 women who undergo lymphadenectomy for breast cancer treatment. One of the most significant morbidities for these patients is recurrent infection secondary to impaired immunity in the lymphedematous limb, often necessitating aggressive preventative precautions such as prophylactic antibiotics. While microsurgical lymph node transfers (LNT) have been shown to improve lymphatic drainage, previous studies have not determined how these procedures impact immune responses. Therefore, the purpose of these experiments was to analyze the potential for LNT to restore immunologic responses in a novel mouse model.
METHODS: We developed a mouse model in which lymphatic vessels can be ablated using diphtheria toxin (DT), enabling us to create localized lymphedema by injecting the limb with a small dose of DT. All animals were injected with DT in the right forepaw to ablate lymphatics and 1 week later underwent axillary lymph node dissection (ALND; n=12). Experimental animals were transplanted with a normal lymph node (LN) and perilymphatic fat from a healthy donor (n=6); control animals had ALND alone (n=6). Normal responses were analyzed in the contralateral limbs, which were sham-operated with no DT injection. We then analyzed the potential for restoration of B cell (antibody) responses by immunizing the animals 3 weeks post-op with ovalbumin (OVA) injection in the right forepaw. T cell memory was also assessed through IFN-gamma production in vitro. In addition, we analyzed the ability of dendritic cells (DCs) to migrate out of the skin/subcutaneous tissues and the ability of these cells to transport peripherally injected Alexa594-conjugated Staphylococcus aureus to transferred LNs. Finally, we measured LN uptake and lymphangiogenesis using Technetium-99m and near-infrared imaging (NIR) with indocyanine green (ICG).
RESULTS: Ablation of lymphatics with DT and ALND resulted in significant (2-fold) increase in forepaw diameter at all time points (weeks 1-3) examined (P<0.01). Animals treated with LNT had significant reduction in forepaw diameter, and more importantly, had greater serum anti-OVA antibody levels than controls (P<0.01). However, the potential to mount antibody responses was still lower than sham-operated controls. This finding was corroborated by increased migration of DCs in LNT treated animals as well as the presence of fluorescent bacteria in the transferred LNs, although the total number of both DCs and bacteria were lower than in sham-operated controls. LNT increased LN drainage (P<0.01) and newly formed lymphatic vessels could easily be seen using ICG and NIR. Interestingly, LNT appeared to increase lymphangiogenesis significantly as compared with controls as analyzed by ICG.
CONCLUSION: Our mouse model of non-invasive lymphatic ablation enables us to create a new model of lymphedema. Using this model we have shown that LNT significantly increases lymphangiogenesis, promotes drainage of interstitial fluid, improves antibody responses, and allows for both migration of DCs from the periphery and bacterial presentation in transferred LNs. However, LNT does not completely restore immune responses (at least in the early post-operative period), suggesting that patients who are treated with this approach should continue infectious precautions.


Back to 2015 Annual Meeting Program