HES 311. Lecture 8: Immunity

Organs and tissues of the immune system

Bone marrow, spleen, thymus gland, tonsils, lymph nodes

Leukocytes

Cells of the immune system

Cytokines, complement system, histamine, bradykinin, prostaglandin, leukotrienes, antigens, antibodies

Molecules of the immune system

Physical and chemical barriers, inflammation, fever

Innate Immune Response: defense mechanism

Kill the compromised cells

Adaptive immune response: defense mechanism

Cells are non-specific
immediate response to a threat
No memory

Components of innate immune response

Cells are specific for each invader
Initial response takes a few weeks
Immunologic memory

Components of adaptive immune response

Recognize specific antigens that have invaded the body before

B lymphocytes

Recognize the specific antigen that is presented

T lymphocytes

Helper T cells
Cytotoxic T cells

2 types of T cells

Secrete cytokines to help coordinate the immune response

Helper T cells

Kill target cells that present a specific antigen

Cytotoxic T cells

1. Live attenuated
2. Inactivated
3. Subunit
4. Toxoid

4 types of vaccination

Pathogen weakened
Still able to replicate
Large immune response

Live attenuated vaccine

Pathogen killed
No cellular immunity
Small immune response

Inactivated vaccine

Contain a portion of the pathogen
B cells only

Subunit vaccine

Developed against specific toxins (inactivated)

Toxoid vaccine

Immune system overreacts to cause damage instead of protection

Hypersensitivity Reactions

immune system cannot distinguish between certain self- and non-self antigens

Autoimmune disorders

The consequence of a defect in one or more components of the immune system

Immunodeficiency

any condition that leaves your body vulnerable to infection because of an issue with the normal functioning of the immune system

immunocompromised condition