Cellular Innate Immunity: Inflammation and Sickness

What is inflammation? Is it beneficial or not?

Complex biological response of body tissues to harmful stimuli between many cells, organs, and microenvironment

Beneficial: eliminate pathogens and control injury

What is purpose of inflammation?

Eliminate pathogen, trigger acquired immunity and systemic responses, minimize/ control injury

What types of events trigger inflammation?

Infections, trauma, physical/chemical injury, tissue necrosis, immune reactions

List the main pro-inflammatory cytokines that trigger acute inflammation?

IL1, IL6, TNF

What are the roles of histamine, leukotrienes, and prostaglandins in inflammation?

Lipid mediators (prostaglandins)-fever

Modified amino acid (histamine)- hypersensitivity response

Lekotrienes - lipid mediators

What are chemokines and their roles in inflammation

Proteins released by immune and non-immune cells to attract immune cells to the inflammatory sites

What are the steps involved in accumulation of neutrophils at the site of injury?

Neutrophils extravasion (rolling → adherence → emigration → blood flow → chemotaxis (attracted)

List the cardinal signs of inflammation. What is the mechanism leading to each of those cardinal signs?

Redness: increased blood flow

Heat: increased blood flow

Swelling: increased vascular permeability + neutrophil emigration

Pain: nerve damage + vasoactive molecules

Loss of function: pain and neurological reflex

What are the local effects of inflammation?

• increased blood flow

• Vascular permeability

• Increased expression of cell adhesion cells

• Inflammatory cytokine production

What is the role of the complement system in inflammation?

Releases anaphaelaxins (C5a and C3a)

What are acute phase proteins and what do they do?

Produced by liver and activates other processes to eliminate pathogen

Increased inflammatory response

How are acute and chronic inflammation different?