The immune system

What are the 5 types of leukocytes?

-Neutrophils

-Lymphocytes

-Monocytes

-Eosinophils

-Basophils

Neutrophils function

Phagocytize, clean-up debris

Usually the first ones on the scene. Die after phagocytosis

Lymphocytes function (B-cells)

Produce antibodies against foreign cells

Lymphocytes (t-cells)

Kill infected or cancerous cells

Natural killer cells are…. (What kind of cells are they)

Lymphocytes / White blood cells

Monocytes

Phagocytize

turn into macrophages (big eater) earn they leave blood and go into tissue

Eosinophils

Allergic reactions

Attach to and kill parasites, worms, Protozoa

Basophils

Histamine: allergic, response

Heparin:prevents clotting

Similar to Mast Cells (fixed in tissues)

Histamine causes

Vasodilation

Macrophages will release

Cytokines, pyrogens and prostaglandins

Prostaglandins bind to

Nocicepters

What 2 cytokines do macrophages secrete?

Interleukin 1 (IL-1)

Tumour Necrotic Factor Alpha (TNF)

Cytokines get into the blood and go to the

Entire system

When cytokines get to the brain the ________( part of the brain), triggers a _______

Hypothalamus; Fever

Which white blood cells react to allergies?

Eosinophils

Basophils

What White blood cells appear Granular?

Netophils, Eosophils, Basophils

Which white blood cells appear Agranular, appear smooth?

Monocytes

lymphocytes

Immune systems first line of defence

skin

Mucous Membranes

Immune system Second line of defence

Phagocytes

Nk cells

Inflammation

Antimicrobial Proteins

Fever

Immune system 3rd line of defence

Humoral Immunity→ B-cellls

Cellular Immunity → Tcells

Innate immunity Time line

Immediate (mins to hours)

Innate Immunity memory

None

3 locations of Mucous Membranes

digestive tract

Urogenital tract

Respiratory tract

Why is mucous Sticky?

To trap particles

The macrophages that operate in the respiratory tract live in the …

Alveoli

How does the respiratory tract propel irritants out?

Coughing and sneezing

Inflammation occurs when:

Tissue is physically or chemically damaged

Pathogens are recognized by WBC

What is involved in Inflammation?

Neutrophils

Monocytes/Macrophages

Mast cells/histamine

Clotting factors

Chemotoxins

The benefits of a moderate fever

Liver and spleen hide iron and zinc

Increase speed of bodily chemical reactions

Decrease pathogen growth

Enhance phagocytosis

High fever leads to

Protein denature

Phagocytosis is don’t by which 2 WBC

Neutrophils and macrophges

Sugar coat finger print

Glycocalyx

Natural Killer cells secrete chemicals called?

Periforins and Granzymes

What to perforis do?

Lyse cell membrane of target through perforation

What do granzymes cause ?

Apoptosis

Job of interferons

Helps cells non-specifically target and prevent replication

Interferons communicate

Paracrinely* via virus blocking enzyme

Complement system is a:

A chain rxn/cascade of molecules that kill infected cells by attacking membrane

Complement system is comprised of ____ plasma proteins

30

Complement system plasma proteins in active form jobs:

Opsonization

Inflamation

Form large hole in cells membrane (MAC)

What is Opsonization

The coating of surface with opsonins to make it easier to phagocytize

Langerhans cells

Recognize pathogens and alert immune system

Bradykinin proteins…(what do they do)

Sensitize nerves

How many hours does it take for Macrophages to peak?

48

2 Branches of adaptive immunity

Antibody-mediated immunity/humoral immunity

Cell mediated immunity

Antibodies make…

B cells

What are antibodies?

Large Y-shaped proteins (immunoglobulins) (Ig)

what do T-cells do?

T cells activate immune responses

Where do B-cells develope

Bone marroe

Where do T cells develope?

Thymus

What is immunocompetence?

The B and T cells will display a unique receptorthat can respond to a distinct antigen

What are antigens?

Substances that provoke adaptive immune response

What do antigens do?

They coat the surface of bacteria, viruses, fungi, pollen, grains, toxins

What does immunogenic mean?

Can stimulate production of certain lymphocytes and anti bodies (ANTIbody GENerating)

What are the 2 antigen characteristics?

Immunogenic

Reactive

What are incomplete antigens called?

Haptens

Anti gens lack the _____to trigger ______ responses on their own

Size (they are too small)

Immune

What is an antigen is determinant?

the immunogenic part of the antigen

Most antigens have

Multiple antigentic determinants.

What are self antigens?

The antigens that are on the surface

The immune cells _______ & _______ self antigens

Recognize; tolerate

Self-antigens are presented by special protein:

Major Histocompatibility Complex

The 2 Major Histocompatibility Complex (MHC) molecules

MHC 1 - present endogenous antigens

MHC 2 - Present exogenous antigens

Major histocompatibility Complex’s are found on ____ ______ cells

All uncleared cells

MHC1 presents:

Normal and abnormal self-antigens

MCH 2 presents

Pathogen antigens

Found on macrophages, b-cells, and dendritic cells

When MHC 2’s are activated they are now called:

Antigen Presenting cells

Antigen Presenting Cells include:

Dendritic cells, macrophages, b-cells

Macrophages will do what in reguards to antigen presenting cells?

Will wait in lymphoid organs

Dendritic cells …

Patrol epidermis and connective tissue, catch pathogens, display antigens, and then travel to lymph nodes to present their “catch”

the activated cloned B-cells differentiate into :

Plamsa Cells

Memory cells

Plasma cells have a reproductive rate of

2000 antibodies per second

Plasma cell life span

4-5 days

What do plasma cells do?

Produce specific antibodies for that pathogen

What do memory cells do?

Stores the memory of antigen to make antibodies later, dormant until next infection

Anti bodies ____ directly destroy pathogens

Can’t

When antibodies physically surround a pathogen to stop it from interacting with other cells, this is called

Neutralization

Agglutination

Clump multiple pathogens and pathogenic molecules together

Precipitation

Agglutination when it occurs in fluids.

Primary Immune Responce lag period

3-6 days

Secondary immune response lag period

Hours

Primary Immune Response anti body level peak time

10 days

Secondary immune response antibody peak time

2-3 days

What is active immunity?

Occurs when B cells encounter antigens and produce anti bodies against them

What are the 2 kinds of active immunity.

Naturally acquired

Artificially required

What is the naturally acquired active immunity

Response to a pathogen

What is the artificially acquired active immunity ?

Response to vaccine

What is passive immunity

B cells that are not activated to challenged by antigens

Naturally Aquired passive immunity happens

From mother to fetus via placenta or IgA in breast milk

Passive immunity is artificially required by

Injection of foreign serum that contain IG’s

What is serum?

Plasma with out clotting factors

What do T-cells do ?

Destroy infected body cells if the pathogen has been able to successfully get into a body cell

T-cells cannot

“See” free antigens

What are the 4 types of T-cells?

Cytotoxic T-cells (CD8), Helper T-cells (CD4), Regulatory T-cells (CD4-25), Memory T-Cells (clones of Th and Tc)

The 2 possibilities of the T-cel and antigens

Pathogen infects body cell

Pathogen is engulfed by Phagocytic cell

What do helper T-cells do?

Release Cytokines→ chemicals that activate other immune cells

Helper T-cells __________ directly

Do not kill

AIDS and HIV targets what cells

Helper T-cells CD4

When B cells differentiate with out Th’s initiation

The response is less efficient

Why are Th cells arguably the most important lymphocyte?

They activate Tc cells

The activate B cells to become plasma cells