Food for thought - ILC metabolism in the context of helminth infections

There's no place like home: How local tissue microenvironments shape the function of innate lymphoid cells

Innate lymphoid cells (ILC) have emerged as critical immune effectors with key roles in orchestrating the wider immune response. While ILC are relatively rare cells they are found enriched within discrete microenvironments, predominantly within barrier tissues. An emerging body of evidence implicates complex and multi-layered interactions between cell types, tissue structure and the external environment as key determinants of ILC function within these niches. In this review we will discuss the specific components that constitute ILC-associated microenvironments and consider how they act to determine health and disease. The development of holistic, integrated models of ILC function within complex tissue environments will inform new understanding of the contextual cues and mechanisms that determine the protective versus disease-causing roles of this immune cell family.

Adult Hymenolepis nana and its excretory-secretory products elicit mouse immune responses via tuft/IL-13 and FOXM1 signaling pathways

BACKGROUND

Hosts typically elicit diverse immune responses to the infection of various parasitic worms, with intestinal epithelial cells playing pivotal roles in detecting parasite invasion. Hymenolepis nana (H. nana) is a zoonotic parasitic worm that resides in the host's intestine. The contribution and underlying mechanisms of tuft cell-mediated immune reactions against H. nana remain unexplored.

METHODS

This study endeavors to examine the immune responses in the mouse intestine elicited by the adult H. nana and its excretory-secretory products (ESP). Ileal tissue alteration was detected using hematoxylin and eosin (H&E) staining, changes in the number of intestinal stem cells, goblet cells, tuft cells, and Paneth cells were detected by immunohistochemistry (IHC), immunofluorescence (IF), etc., and changes in the expression of type 2 cytokines and FOXM1 were detected by Western blotting (WB) or real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

The presence of adult H. nana and its ESP enhanced the number of tuft cells and goblet cells while fostering the production of type 2 cytokines. Furthermore, the surge in Paneth cells and FOXM1 triggered by H. nana aids in maintaining intestinal stem cells homeostasis and proliferation. Notably, the FOXM1 inhibitor RCM-1 dampened intestinal stem cells differentiation and type 2 cytokines secretion, potentially impeding the host's capacity to eliminate H. nana.

CONCLUSIONS

The adult H. nana and its ESP stimulate the immune responses in mice through tuft/interleukin (IL)-13 and FOXM1 signaling pathways and promote the elimination of H. nana from the host through the differentiation of intestinal stem cells into tuft cells, goblet cells, and Paneth cells, as well as the activation of type 2 immune responses. Meanwhile, RCM-1 inhibits the immune responses to H. nana in mice, thus affecting the excretion of H. nana by host.

Immunometabolic reprogramming, another cancer hallmark

Molecular carcinogenesis is a multistep process that involves acquired abnormalities in key biological processes. The complexity of cancer pathogenesis is best illustrated in the six hallmarks of the cancer: (1) the development of self-sufficient growth signals, (2) the emergence of clones that are resistant to apoptosis, (3) resistance to the antigrowth signals, (4) neo-angiogenesis, (5) the invasion of normal tissue or spread to the distant organs, and (6) limitless replicative potential. It also appears that non-resolving inflammation leads to the dysregulation of immune cell metabolism and subsequent cancer progression. The present article delineates immunometabolic reprogramming as a critical hallmark of cancer by linking chronic inflammation and immunosuppression to cancer growth and metastasis. We propose that targeting tumor immunometabolic reprogramming will lead to the design of novel immunotherapeutic approaches to cancer.