Nasal submucosal administration of antigen-presenting cells induces effective immunological responses in cancer immunotherapy.

Human NKT cells are known to have strong antitumor activities and to be activated by specific ligand, α-galactosylceramide (αGelCer). We examined the migration pattern of αGalCer-pulsed DCs and the immune responses after administration by different routes. DCs injected into nasal submucosa quickly migrated to the lateral neck lymph rather than the lateral lymph nodes. The absolute number of NKT cells and the IFN-γ-producing cells increased in peripheral blood after injection of the DCs into nasal submucosa. We conducted a phase I study with αGalCer-pulsed DCs administered in nasal submucosa of patients with head and neck cancer, and evaluated safety and feasibility. The results showed that nasal submucosal administration of α-GalCer-pulsed DCs was safe and a smaller number of these DCs could exhibit significant immune responses and some positive clinical effects. In additional study, the use of the intra-arterial infusion of activated NKT cells and the submucosal injection of α-GalCer-pulsed DCs has been shown to induce significant antitumor immunity and had beneficial clinical effects in the management of advanced head and neck squamous cell carcinoma. The NKT cell-based cancer immunotherapy may be helpful in management of head and neck cancer and needs to be explored in further detail.

Migration and immunological reaction after the administration of αGalCer-pulsed antigen-presenting cells into the submucosa of patients with head and neck cancer.

BACKGROUND: Antigen-presenting cells (APCs) play a crucial role in the induction of immune responses. However, the optimal administration route of tumor-specific APCs for inducing effective immunological responses via cancer immunotherapy remains to be elucidated. Human NKT cells are known to have strong anti-tumor activities and are activated by the specific ligand, namely, α-galactosylceramide (αGalCer). METHODS: Seventeen patients with head and neck squamous cell carcinoma (HNSCC) were enrolled in this study. Patients received an injection of αGalCer-pulsed APCs into the nasal, or the oral floor submucosa. Then total body image and single photon emission computed tomography (SPECT) images were examined. The immunological responses including the number of peripheral blood NKT cells, anti-tumor activities and the CD4(+) CD25(high) Foxp3(+) T cells (Tregs) induced following APCs were also compared. RESULTS: APCs injected into the nasal submucosa quickly migrated to the lateral lymph nodes and those injected into the oral floor submucosa dominantly migrated to the submandibular nodes rather than the lateral lymph nodes. An increase in the absolute number of NKT cells and the IFN-γ producing cells was observed in peripheral blood after injection of the APCs into the nasal submucosa, however, these anti-tumor activities were not detected and the increased frequency of Treg cells were observed after administration into oral floor. CONCLUSIONS: These results indicate that a different administration route of APCs has the potential to bring a different immunological reaction. The submucosal administration of αGalCer into the oral submucosa tends to induce immunological suppression.

Induction of NKT cell-specific immune responses in cancer tissues after NKT cell-targeted adoptive immunotherapy.

Vα24 natural killer T (NKT) cells have potent anti-tumor activity. We performed a phase II clinical study in patients with head and neck squamous cell carcinoma (HNSCC) using ex vivo expanded Vα24 NKT cells and α-galactosylceramide (αGalCer; KRN7000)-pulsed antigen-presenting cells (APCs) to investigate the efficacy and induction of NKT cell-specific immune responses. The subjects were 10 patients with locally recurrent and operable HNSCC. One course of nasal submucosal administration of αGalCer-pulsed APCs and intra-arterial infusion of activated NKT cells via tumor-feeding arteries was given before salvage surgery. Anti-tumor effects, NKT cell-specific immune responses in extirpated cancer tissue and peripheral blood, safety, and pathological effects were evaluated. Five cases achieved objective tumor regression. The number of NKT cells increased in cancer tissues in 7 cases and was associated with tumor regression. The combination therapy induced NKT cell-specific immune responses in cancer tissues that were associated with beneficial clinical effects.