Chronic Inflammation: Introduction

Chronic inflammation is a prolonged, persistent immune response that can last for weeks, months, or even years.

Chronic inflammation involves a distinct set of immune cells.

There is typically less swelling and fluid buildup, but more cellular infiltration by lymphocytes, macrophages, fibroblasts, and connective tissue cells involved in repair and scarring.

Ongoing immune activity leads to progressive tissue destruction.

Macrophages and other immune cells release enzymes and reactive molecules that not only target the affected area but also damage surrounding healthy tissue.

To contain this damage, fibroblasts increase collagen production, resulting in fibrosis, the buildup of scar tissue.

In some chronic conditions, the immune system forms a granuloma, a compact and organized structure of activated macrophages that helps contain pathogens and foreign material. It is often surrounded by lymphocytes and connective tissue.