Lect 30 - intro to immunology and immune system

Flashcards covering introduction to immunology, the immune system, lymphoid organs, layers of defense, physical and chemical barriers, and innate vs. adaptive immunity.

Immunology

The study of an organism's defense system (immune system) in health and disease.

Immune System

An organized system of organs, cells, and molecules that interact to defend the body against disease.

Name some diseases that the immune system defends against.

• HIV/AIDS,

• Tuberculosis,

• Influenza,

• Malaria,

• SARS-CoV-2,

• Arthritis/rheumatism,

• Allergy/asthma,

• Lupus,

• Diabetes,

• Crohn’s disease/inflammatory bowel disease,

• Multiple sclerosis.

List Microbes from Smallest to Largest

Viruses, Bacteria, Fungi, Protozoa

What are the primary lymphoid organs?

Thymus and Bone Marrow

What are primary lymphoid organs responsible for?

Production of white blood cells (lymphocytes).

What is the role of the Thymus?

A 'school' for white blood cells called T cells, where developing T cells learn not to react to self.

What is the role of the Bone Marrow?

Source of stem cells that develop into cells of the ‘innate’ and ‘adaptive’ immune responses

What are the secondary lymphoid organs?

Spleen and Lymph Nodes

What is the role of the Spleen?

Site of initiation for immune responses against blood-borne pathogens.

What are lymph nodes?

Located along lymphatic vessels and Filter lymph fluid from blood and tissue.

What are the 3 layers of defense?

1. Chemical and physical barriers,

2. Innate immune arm,

3. Adaptive immune arm

What are the physical barriers of the skin?

Epidermis and Dermis

What are the chemical defenses of the skin?

Antimicrobial peptides, Lysozyme, Sebum, Salt

What are the physical barriers for protection?

Skin and Mucosal surfaces

What are the Mucous membranes?

Epithelium

What's Mucociliary elevator?

Moves mucus up from our respiratory system up into the pharynx to cough up or swallow

• 200-300 cilia on columnar cells push up the mucus to the pharynx

• Gets rid of the microbe before it causes harm

What are the chemical defenses of mucosal surfaces?

Low pH, Bile, Digestive enzymes, Mucus, Defensins, Lysozyme

What are the characteristics of Innate Immunity?

Already in place, Rapid, Fixed, Limited specificities, No specific memory

What are the characteristics of Adaptive Immunity?

Improves during the response, Slow, Variable, Highly specific, Has long-term specific memory

epidermis features

dead cells, keratin, phagocytic immune cells (dendritic cells)

dermis

thick layer of connective tissue

collagen and blood vessels and phagocytic immune cells

antimicrobial peptides

Form pores in microbial cell membranes

Lysozyme (found in sweat)

Breaks down bacterial cell walls

sebum (produced by sebaceous glands)

low pH, acidic nature of sebum prevent microbial growth

salt (sweat glands)

hypertonic, draws water out of pathogen and dehydrates the pathogen

what is epithelium?

tightly packed live cells, constantly renewed, mucus producing goblet cells

What are mucus producing goblet cells

produce mucus and provide mucus layer

• keeps moits

• functions as a physical trap for microbes