Curative-intent lymphoablation is the standard of care for advanced HNSCC patients, creating a central paradox as novel immunotherapies become less effective after partial loss of function of the lymphatic tissue; as such, patients lack the immune strength and response mechanisms needed for the full functionality of cancer immunotherapy treatment after lymphatic resection.

Design Choice: Tissue Engineered Lymph Node Scaffold from Decellularized Lymph Node

Decellularization of organs yields acellular extracellular matrices that can act as scaffolds for tissue engineering. The technique allows us to bypass the challenge of recreating complex lymph node architecture de novo, while also providing the physical structures that allow for proper dendritic cell seeding that we believe will re-establish lymphatic functions.

Alternative I: Tissue-Engineered Lymph Node Organoid

Instead of decellularization, stromal cells can be seeded into a collagen-based scaffold to mimic the fundamental structural characteristics of lymph nodes, allowing greater control to recreate the microenvironment for proper immune cell clustering. Using a collagen-based scaffold allows for independence from animal sources for scaffolds and avoids variability in size and behavior of organs harvested for decellularization.

Alternative II: Tissue Engineered Injectable Scaffold for the Extended Release of Chemokines

A minimally invasive alternative design solution involves the creation of an injectable hydrogel that contains extracellular matrix, growth factors, and chemokines to recreate the immune environment of a lymph node. The immunostimulatory biochemical cues provided by these biological components will dictate and guide cell interactions within the body to rescue the immune response to anti-CTLA-4 based immunotherapies.

Alternative III: Application of Cytokine Cocktail to Alleviate the Inhibitory Environment Towards Immunotherapies Created by the Tumor

Interleukins and other cytokines have been injected and studied in patients with different cancers, many of which have shown a significant increase in neutrophil count and lymphoid tissue activation in both the short-term and long-term prognosis of cancer patients. Application of the cytokines’ ability to negate the inhibitory microenvironment of the lymph node to head and neck cancer patients can be an alternative design solution, in which the patient’s response to anti-CTLA4 immunotherapy following this prior treatment would be evaluated for efficacy.

Based on the matrix above, Design 1 (decellularized lymph node) is most likely to successfully meet the enumerated goals. Although it may be less successful at mimicking the immune microenvironment of a native lymph node than other designs, the decellularized lymph node is the most likely of these designs to be safe for implantation and to be able to most effectively rescue the immune response and lymphatic drainage within a post-surgery mouse. In addition, given constraints of time and budget, the decellularized scaffold will be the easiest model to create and characterize in vitro within the given timeframe.