Inflammation & repair

Function of immunity 

Identify a threat, mount an attack, eliminate pathogen and develop mechanisms to remember offender 

Innate immune system

• Non-specific

• Fast

• No memory

Adaptive immune system

• Specific

• Slow

• Memory involved

What is inflammation?

A reaction to injurious agents

What would happen if we didn’t have an inflammatory response?

• Infections would go unchecked

• Wounds wouldn't heal

• Tissues would remain in a festering state

Neutrophils

WBC in acute inflammatory response which helps destroy foreign substances through phagocytosis

Eosinophils

Involved in allergic reactions and more associated with chronic inflammation

Basophils

WBC that release histamine to increase vascular permeability and blood flow

Mediators 

Chemicals released which amplify or trigger the inflammatory response 

Example of a mediator

Histamine

Difference between acute and chronic inflammation?

Rubor

Redness

• Caused by dilation of blood vessels in the local area

  • When blood vessels increase, their calibre would dilate and red blood cells move into that area

  • Arterial blood flow to the area due to vasodilation is going to cause redness

Tumor 

Swelling

• Due to increased vessel permeability and a movement of fluid from inside the blood vessels and capillaries into the tissue, we end up with swelling of that tissue

Calor

Heat

• Increased arterial blood flow from increased dilation of blood vessels increases heat of that tissue

Dolor

Pain

• Sensory nerve supply to our bodily structures and the increase in fluid pressure as a result of fluid exiting the blood vessels sitting in that

Describe the structure of an abscess

Central necrotic core, peripheral halo of phagocytes, surrounded by capsule of vessels and fibroblasts