ABSTRACT
Intratumor and gut mycobiome is linked to pancreatic ductal adenocarcinoma (PDAC) tumorigenesis; however, an optimal approach to culture and transplant fungus into mouse for in vivo studies is missing. This protocol describes culture steps of Alternaria alternata and Malassezia globosa and their subsequent transplantation into a PDAC mouse model via oral gavage. The utilization of the fungal culture method will allow for consistent growth and expansion of specific fungal species for downstream processing. For complete details on the use and execution of this protocol, please refer to Alam et al. (2022).
Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Animals , Carcinogenesis/pathology , Carcinoma, Pancreatic Ductal/surgery , Mice , Pancreatic Ducts/pathology , Pancreatic Neoplasms/surgery , Pancreatic NeoplasmsABSTRACT
Innate lymphoid cells 2 (ILC2) play a significant role in the tumorigenesis of pancreatic ductal adenocarcinoma (PDAC). An important aspect of ILC2-mediated tumorigenesis is the expansion of the resident ILC2 and simultaneous recruitment of the peripheral ILC2. Here, we describe a protocol for isolation, enrichment, and DiD labeling of ILC2 for in vivo tracking of ILC2s in the mouse. Further, we describe steps for the adoptive transfer of ILC2 to a recipient mouse model of PDAC. For complete details on the use and execution of this protocol, please refer to Alam et al. (2022).
Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Adoptive Transfer , Animals , Carcinogenesis , Carcinoma, Pancreatic Ductal/therapy , Disease Models, Animal , Immunity, Innate , Lymphocytes , MiceABSTRACT
TH2 cells and innate lymphoid cells 2 (ILC2) can stimulate tumor growth by secreting pro-tumorigenic cytokines such as interleukin-4 (IL-4), IL-5, and IL-13. However, the mechanisms by which type 2 immune cells traffic to the tumor microenvironment are unknown. Here, we show that oncogenic KrasG12D increases IL-33 expression in pancreatic ductal adenocarcinoma (PDAC) cells, which recruits and activates TH2 and ILC2 cells. Correspondingly, cancer-cell-specific deletion of IL-33 reduces TH2 and ILC2 recruitment and promotes tumor regression. Unexpectedly, IL-33 secretion is dependent on the intratumoral fungal mycobiome. Genetic deletion of IL-33 or anti-fungal treatment decreases TH2 and ILC2 infiltration and increases survival. Consistently, high IL-33 expression is observed in approximately 20% of human PDAC, and expression is mainly restricted to cancer cells. These data expand our knowledge of the mechanisms driving PDAC tumor progression and identify therapeutically targetable pathways involving intratumoral mycobiome-driven secretion of IL-33.
