30: Intro to Inflammation

Branch of immunity that is related to inflammation

Innate immunity → non-specific!

Requirements for inflammation

Living and vascularized tissue

How is inflammation beneficial

It brings in cells and defense molecules

T/F: inflammation is bad

False, inflammation is a protective response!

Holding layer of tissues

Submucosa!!

How to tell if a lesion found on necropsy happened post/antemortem

Look for signs that there was redness and hemorrhage. Both are signs of inflammation, and would indicate that the lesion is antemortem

Definition of acute inflammation

Less than 1 week

Definition of chronic inflammation

3ish weeks or more

T/F: inflammation is always set off by an initiating event

True

What do we mean when we say that inflammation is a double edged sword

It causes collateral tissue damage

Cirrhosis

Scarring

Atherosclerosis

Thickened vessels due to M1 and cholesterol

Proud flesh

Tissue wound repair that won’t stop

Plasma components that are part of the inflammatory process

Clotting factors, acute phase proteins, lots of stuff from the liver

Cellular components that are part of the inflammatory process

NEUTROPHILS, also macrophages and other cells

How are blood vessels part of the inflammatory process

They are dynamic, bringing things to the tissues

How is CT part of the inflammatory process

The cellular and extracellular components outside the vascular space participate

How does inflammation do most of its communicating

Through cell surface communication

Key cellular player in acute inflammation

Neutrophils

Key cellular player in chronic inflammation

Macrophages

Which type of inflammation can be characterized by fibrosis

Chronic → fibrosis takes time!

Generalized causes of inflammation

• Infectious agents

• Tissue necrosis

• Foreign bodies

• Immune reactions

Type of infectious agent that commonly causes chronic inflammation

Fungi and fungus-like organisms

Why does necrosis cause inflammation

Inflammation helps clear away the dead tissue

Systemic signs of inflammation

• Leukocytosis

• Fever

• Sepsis and shock

Type of leukocytosis characteristic of acute or bacterial inflammation

Neutrophils

Type of leukocytosis characteristic of chronic viral inflammation

Lymphocytes

Why is a fever commonly seen with inflammation

• Though to aid in leukocyte killing

• May impair pathogen replication

Septic shock is specific to what type of inflammatory cause

Bacterial infection that causes endotoxemia

Three ways for acute inflammation to end

• Resolution: minimal tissue damage

• Repair: resolution, but there is scarring

• Persists to become chronic inflammation