Effective anti-tumor immune responses are orchestrated by immune cell partnership network that functions through tissue homeostatic pathways, not direct cytotoxicity.

The liver hosts a diverse array of immune cells that play pivotal roles in both maintaining tissue homeostasis and responding to disease. However, the precise contributions of these immune cells in the progression of nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) remain unclear. Utilizing a systems immunology approach, we reveal that liver immune responses are governed by a dominant-subdominant hierarchy of ligand-receptor-mediated homeostatic pathways.

From Reductionistic Approach to Systems Immunology Approach for the Understanding of Tumor Microenvironment.

The tumor microenvironment (TME) is a complex and dynamic ecosystem that includes a variety of immune cells mutually interacting with tumor cells, structural/stromal cells, and each other. The immune cells in the TME can have dual functions as pro-tumorigenic and anti-tumorigenic. To understand such paradoxical functions, the reductionistic approach classifies the immune cells into pro- and anti-tumor cells and suggests the therapeutic blockade of the pro-tumor and induction of the anti-tumor immune cells.

The crosstalking immune cells network creates a collective function beyond the function of each cellular constituent during the progression of hepatocellular carcinoma.

Abundance of data on the role of inflammatory immune responses in the progression or inhibition of hepatocellular carcinoma (HCC) has failed to offer a curative immunotherapy for HCC. This is largely because of focusing on detailed specific cell types and missing the collective function of the hepatic immune system. To discover the collective immune function, we take systems immunology approach by performing high-throughput analysis of snRNAseq data collected from the liver of DIAMOND mice during the progression of nonalcoholic fatty liver disease (NAFLD) to HCC.

Restoration of CD4 T Cells during NAFLD without Modulation of the Hepatic Immunological Pattern Is Not Sufficient to Prevent HCC.

Predominant inflammatory immunological patterns as well as the depletion of CD4 T cells during nonalcoholic fatty liver disease (NAFLD) are reported to be associated with the progression of hepatocellular carcinoma (HCC). Here, we report that an LRP-1 agonistic peptide, SP16, when administered during advanced NAFLD progression, restored the depleted CD4 T cell population but did not significantly affect the inflammatory immunological pattern. This data suggests that restoration of CD4 T cells without modulation of the hepatic immunological pattern is not sufficient to prevent HCC.