Tumor immunology has been studied extensively. Tumor immunology–based cancer immunotherapy has become one of the most promising approaches for cancer treatment. However, one of the fundamental aspects of tumor immunology—the initiation of antitumor immunity—is not fully understood. Compared to that of CD8+ T cells, the effect of CD4+ T cells on antitumor immunity has not been fully appreciated. Using a gene knockout mouse model, the mice of which are deficient in the TCRα repertoire, specifically lacking invariant NKT and mucosal-associated invariant T cells, we found that the deficiency in TCRα repertoire diversity did not affect the antitumor immunity, at least to B16BL6 melanoma and EO771 breast cancer. However, after acquiring thymocytes or splenocytes from wild-type mice, these knockout mice exhibited greatly enhanced and long-lasting antitumor immunity. This enhanced antitumor immunity depended on CD4+ T cells, especially CD4+ tissue-resident memory T (TRM) cells, but not invariant NKT or CD8+ T cells. We also present evidence that CD4+ TRM cells initiate antitumor immunity through IFN-γ, and the process is dependent on NK cells. The CD4+ TRM/NK axis appears to control tumor formation and development by eliminating tumor cells and modulating the tumor microenvironment. Taken together, our results demonstrated that CD4+ TRM cells play a dominant role in the initiation of antitumor immunity.

The prevalence of diet-induced obesity and type-2 diabetes remains a growing concern in the United States. As best management practices still include improved diet and physical activity, bioactive food components, contained within functional foods, show promise in curbing the cardiometabolic complications associated with excess weight and diabetes. Quinoa is an emerging candidate crop for its versatility in wide-ranging growing conditions as one approach to address food security, but it also contains several components that may serve as a dietary tool for post-industrial countries struggling with the health complications of caloric excess. Preliminary rodent feeding studies demonstrate that components within quinoa, namely, phytosteroids, phenolics, polysaccharides, and peptides, can prevent adiposity, dyslipidemia, and hyperglycemia. Mechanistic activity may involve reduced lipid absorption and adipogenesis, increased energy expenditure and glucose oxidation and corrected gut microbiota. Other intestinal actions may include blocked carbohydrate digestion with enhanced incretin signaling. Evidence in clinical trials is lacking and future research spanning cells to the clinic is needed to further elucidate the interesting preliminary reports reviewed here. Quinoa offers several unique attributes that could be harnessed to improve the dietary management of obesity and diabetes.