#1 Intro to immune function (innate)

What constitutes disease (“dis-ease”)?

Any harmful, abnormal condition that disrupts normal structure or function of an organism

What does DAMNN-IITT stand for?

A framework describing major causes of disease

DAMNN-IITT

Degenerative / Developmental

Autoimmune

Metabolic

Neoplastic

Nutritional

Infectious (+ parasitic)

Iatrogenic

Toxicological

Traumatic

What are degenerative or developmental diseases?

Diseases that occur due to problems during fetal development or that worsen with age

What is an example of a degenerative disease?

Multiple sclerosis (MS)

Autoimmune disease

A disease where the immune system attacks the body’s own cells

Genetic disease

A disease caused by inherited genetic abnormalities

What is an example of a genetic disease?

Sickle cell anemia

Metabolic Disease

A disease caused by disruptions in normal metabolism, including hormone imbalances

What is an example of a metabolic disease?

Diabetes

Neoplastic Disease

Diseases involving abnormal cell growth, such as cancers

Are neoplastic diseases usually population-limiting?

No, they generally are not population-limiting

What causes nutritional diseases?

Deficiencies or toxicities of nutrients such as selenium or copper

Why do we supplement animals with vitamins and minerals?

To prevent deficiencies

What happens if supplementation is excessive?

It can become toxic

What causes infectious and parasitic diseases?

Pathogens such as bacteria, viruses, fungi, and parasites

Why do we focus heavily on infectious disease in this course?

Because it is one category of DAMNN-IITT, but a major driver of disease dynamics and transmission

Iatrogenic Disease

Disease caused by human activity, such as medical treatment, capture, or management practices

What is an example of iatrogenic disease?

Capture myopathy

How can translocation contribute to disease? (on the individual level)

Capture and stress can alter the vascular system and immune response, making animals sick

Does capture myopathy usually cause sudden death?

No, not typically sudden.

Toxicological Disease

Diseases caused by exposure to toxins, poisons, or chemicals

What are some examples of toxicological disease?

• Avian botulism

• Pesticide poisoning

• Rodenticide exposure

• Fertilizer exposure

What causes traumatic disease?

Physical injury

What are some examples of traumatic disease sources?

• Cars

• Towers

• Window strikes

• Wind turbines

How do traumatic diseases affect animals?

They cause changes in anatomy and physiology that impair daily function

Why is the immune system essential for life?

Hosts are constantly exposed to parasites, and immune defenses are required to survive

What does homeostasis mean in the immune system?

Removal of worn-out or abnormal cells to maintain internal balance

What are the three major ways animals defend themselves from microorganisms?

• Physical barriers

• Innate (non-specific) immunity

• Acquired (specific) immunity

What role do physical barriers play in immunity?

They act as the first line of defense and are always present

What are some examples of physical barriers?

• Skin and mucous membranes

• High body temperature (birds & mammals)

• Normal gut flora

• Acidic stomach pH

• Cilia in respiratory and urogenital tracts

Which cells are involved in innate immunity?

• Monocytes

• Macrophages

• Neutrophils

• Natural killer (NK) T-cells

Degranulation

Release of enzymes that damage pathogen membranes and recruit other immune cells

Phagocytosis

Engulfing and digesting pathogens by immune cells

Which cells are key phagocytes?

• Monocytes

• Macrophages

• Neutrophils

Inflammation

An immune response that increases blood flow and white blood cell recruitment

What are the four cardinal signs of inflammation?

• Pain

• Heat

• Redness

• Swelling

What is a common consequence of inflammation?

Local loss of function

Cytokines

Proteins that allow immune cells to communicate and regulate responses

Interleukins

Cytokines that promote differentiation of B and T lymphocytes

Interferons

Cytokines involved in antiviral and anticancer defense

What is the complement (C’) system?

A cascade of proteins in blood and on membranes that amplify immune responses

Opsonin

A molecule that coats pathogens to promote phagocytosis

Which molecules act as opsonins?

• Complement proteins

• Antibodies

What produces antibodies?

B lymphocytes (B-cells) as part of the acquired immune response.

Which immune defenses are always present?

Physical barriers

Which immune response acts fastest?

Innate immunity

Which immune response takes time to develop?

Acquired (adaptive) immunity