What is the Origin of Immune Cell Infiltration?

This term is fundamental to immunology and pathology, combining "immune cell" with "infiltration," referring to the passive or active movement into a substance or area. In the context of metabolic health, the concept gained prominence with the recognition of obesity as a state of chronic, low-grade inflammation. The degree of infiltration is a critical clinical marker of tissue pathology and dysfunction.

What is the Mechanism of Immune Cell Infiltration?

In dysfunctional adipose tissue, for example, enlarged, stressed adipocytes release pro-inflammatory signaling molecules called chemokines. These signals recruit circulating immune cells, particularly macrophages, to the site of stress. Once infiltrated, these immune cells release inflammatory cytokines, which further impair local insulin signaling and contribute to systemic insulin resistance. This chronic inflammatory state links hormonal dysfunction to metabolic decline.

Immune Cell Infiltration ∞ Area

Immune Cell Infiltration

Meaning

Immune Cell Infiltration describes the process where various immune cells, such as macrophages, lymphocytes, and neutrophils, migrate from the bloodstream into a specific tissue or organ. While a necessary response during acute infection or injury, chronic, low-grade infiltration into metabolically active tissues like adipose tissue or the liver is a hallmark of chronic inflammation and metabolic disease. This persistent presence of immune cells significantly alters local tissue function.