Immunity from NK Cell Subsets Is Important for Vaccine-Mediated Protection in HPV+ Cancers.

High-risk human papillomaviruses (HPVs) are associated with genital and oral cancers, and the incidence of HPV+ head and neck squamous cell cancers is fast increasing in the USA and worldwide. Survival rates for patients with locally advanced disease are poor after standard-of-care chemoradiation treatment. Identifying the antitumor host immune mediators important for treatment response and designing strategies to promote them are essential. We reported earlier that in a syngeneic immunocompetent preclinical HPV tumor mouse model, intranasal immunization with an HPV peptide therapeutic vaccine containing the combination of aGalCer and CpG-ODN adjuvants (TVAC) promoted clearance of HPV vaginal tumors via induction of a strong cytotoxic T cell response. However, TVAC was insufficient in the clearance of HPV oral tumors. To overcome this deficiency, we tested substituting aGalCer with a clinically relevant adjuvant QS21 (TVQC) and observed sustained, complete regression of over 70% of oral and 80% of vaginal HPV tumors. The TVQC-mediated protection in the oral tumor model correlated with not only strong total and HPV-antigen-specific CD8 T cells, but also natural killer dendritic cells (NKDCs), a novel subset of NK cells expressing the DC marker CD11c. Notably, we observed induction of significantly higher overall innate NK effector responses by TVQC relative to TVAC. Furthermore, in mice treated with TVQC, the frequencies of total and functional CD11c+ NK cell populations were significantly higher than the CD11c- subset, highlighting the importance of the contributions of NKDCs to the vaccine response. These results emphasize the importance of NK-mediated innate immune effector responses in total antitumor immunity to treat HPV+ cancers.

Circulating neutrophils and tumor-associated myeloid cells function as a powerful biomarker for response to chemoradiation in locally advanced cervical cancer.

Purpose: The immune system's role in mediating the cytotoxic effects of chemoradiotherapy remains not completely understood. The integration of immunotherapies into treatment will require insight into features and timing of the immune microenvironment associated with treatment response. Here, we investigated the role of circulating neutrophils and tumor-associated myeloid cells (TSAMs) as potential agents and biomarkers for disease-related outcomes in locally advanced cervical cancer (LACC). Material and Methods: Hematologic parameters for two LACC patient cohorts, a retrospective clinical and a prospective translational cohort, were obtained at baseline, weekly during chemoradiotherapy for the retrospective cohort, biweekly during chemoradiotherapy for the prospective cohort, and at the first follow-up visit for both cohorts (mean 14.7 weeks, range 8.1-25.1 weeks for the prospective cohort and 5.3 weeks with a range of 2.7-9.0 weeks for the retrospective cohort). In both cohorts, baseline as well as mean and lowest on-treatment values for platelets, hemoglobin, absolute neutrophil count (ANC), and absolute lymphocyte count (ALC) were analyzed for correlations with disease-related outcomes. In the prospective cohort, circulating myeloid cells were isolated from peripheral blood mononuclear cells (PBMCs), and TSAMs were isolated from tumor tissue via a novel serial cytobrush sampling assay. The samples were analyzed by flow cytometry. Results: In both cohorts, the only hematologic parameter significantly associated with survival was elevated on-treatment mean ANC (mANC), which was associated with lower local failure-free and overall survival rates in the retrospective and prospective cohorts, respectively. mANC was not associated with a difference in distant metastases. CD11b+CD11c- TSAMs, which act as a surrogate marker for intratumoral neutrophils, steadily decreased during the course of chemoRT and nadier'd at week 5 of treatment. Conversely, circulating myeloid cells identified from PBMCs steadily increased through week 5 of treatment. Regression analysis confirmed an inverse relationship between circulating myeloid cells and TSAMs at this time point. Conclusions: These findings identify on-treatment mean neutrophil count as a predictor of disease-related outcomes, suggest that neutrophils contribute to chemoradiation treatment resistance, and demonstrate the importance of techniques to measure intratumoral immune activity.

Mucosal Vaccination With Recombinant Tm-WAP49 Protein Induces Protective Humoral and Cellular Immunity Against Experimental Trichuriasis in AKR Mice.

Trichuriasis is one of the most common neglected tropical diseases of the world's poorest people. A recombinant vaccine composed of Tm-WAP49, an immunodominant antigen secreted by adult Trichuris stichocytes into the mucosa of the cecum to which the parasite attaches, is under development. The prototype is being evaluated in a mouse model of Trichuris muris infection, with the ultimate goal of producing a mucosal vaccine through intranasal delivery. Intranasal immunization of mice with Tm-WAP49 formulated with the adjuvant OCH, a truncated analog of alpha-GalCer with adjuvanticity to stimulate natural killer T cells (NKT) and mucosal immunity, induced significantly high levels of IgG and its subclasses (IgG1 and IgG2a) in immunized mice. This also resulted in a significant reduction of worm burden after challenge with T. muris-infective eggs. The addition of QS-21 adjuvant to this vaccine formulation further reduced worm counts. The improved protection from the dual-adjuvanted vaccine correlated with higher serum antibody responses (IgG, IgG1, IgG2a, IgA) as well as with the induction of antigen-specific IgA in the nasal mucosa. It was also associated with the robust cellular responses including functional subsets of CD4 T cells producing IL-4, and cytotoxic CD8 T cells expressing granzyme B. The worm reduction achieved by mucosal immunization was higher than that induced by subcutaneous immunization. Intranasal immunization also induced a significantly higher nasal mucosa-secreted antigen-specific IgA response, as well as higher functional cellular responses including CD4+IL4+ (Th1) and CD8+GnzB+ (Th2) T cells, and antigen-specific INFγ-producing T cells in both spleen and MLNs and antibody-producing B cells (CD19+B220+/B220+GL7+). Mucosal immunization further induced long-term T lymphocyte memory with increased central (CD62L+CD44+) and effector (CD62L-CD44+) memory subsets of both CD4 and CD8 T cells at 60 days after the last immunization. In summary, intranasal immunization with recombinant Tm-WAP49 protein induced strong protection versus murine trichuriasis. It represents a promising vaccination approach against intestinal nematodes.