IS lesson 3

Innate immunity

Consists of defenses against infection that are ready for immediate action when a host is attacked by a pathogen.

External

anatomical barriers designed to keep microorganisms from entering the body

Internal

cellular responses that recognize specific molecular components of pathogens

External

Internal

2 types of Innate immunity?

Phagocytosis

engulfment and destruction of foreign cells or particles by leukocytes, macrophages, and other cells.

Phagocytosis + Inflammation = bring cells to injured area = healing process

______+ ______= bring cells to injured area = ___________

unbroken skin,

mucosal membrane surfaces,

secretions.

The first line of defense against infection

Pathogen-associated molecular patterns

Natural immunity focuses more on a few large groups of microorganisms called?

Pattern recognition receptors (PRRs)

The receptor of the innate immunity that recognizes these PAMPs are called?

External Defense System

Physical, chemical, and biological barriers that function together to prevent most infectious agents from entering the body.

Normal flora

Microbiota is formerly knows as?

Microbiota

Mix of bacteria that are normally foun at specific body sites and do not typically cause disease

Cellular

1. Mast cell

2. Neutrophils

3. Macrophages

Humoral

1. Complement

2. Lysozyme

3. Interferon

The second line of defense

Epidermis

Keratin

It is coated with a protein called "_____"

Makes skin impermeable to most infectious agents

Renewed every few days to keep it intact

Epidermis

Dermis

Psoriasin

3 parts of the skin

Psoriasin

E.coli

Small protein that has antibacterial effects (esp. against Gr Neg organisms: ?)

Sweat

Produces lactic acid?

Sebaceous gland

5.6 pH

What gland that has _._ pH- acidic pH that keeps most microorganisms from growing

Surfactants

produced by epithelial cells and bind to microorganisms to help move pathogen out

Respiratory Tract

Mucous secretions: block the adherence of bacteria to epithelial cells

Cilia

motion in nasopharyngeal passages clears 90% of deposited material.

Cough and Sneeze

It helps to move pathogens out of the respiratory tract

Urine

Flushing out and acidity helps to remove many potential pathogens from the genitourinary tract

Vagina

Lactic acid: keeps pH of about 5, which prevents invasion of pathogens.

Digestive tract

HCI - has a pH of 1, serves to halt microbial growth

Tears and Saliva

Lysozyme: attacks the cell walls of microorganisms, esp. those that are gram-positive

Internal Defense System

Composed of both cells and soluble factors that have specific and essential functions.

Most important function: PHAGOCYTOSIS

Acute Phase Reactants

Pattern recognition receptor

• determine which molecules are immunogenic.

• Encoded by the host's genomic DNA and act as sensors for extracellular infection

• Able to distinguish self from non-self by recognizing substances

Pathogen-associated Molecular Patterns

molecules associated with groups of pathogens that are recognized by cells of the innate immune system.

Peptidoglycan

Gram positive bacteria

Lipopolysaccharide

Gran Negative Bacteria

Zymosan

Yeast

Flagellin

Bacteria with flagellae

Charles Janeway

Who discovered the TLR?

Toll-Like Receptor (TLR)

• a set of transmembrane receptors that recognize different types of PAMPs.

• Highest concentration on monocytes, macrophages, dendritic cells

End result: production of cytokines and chemokines to eliminate microbes

TL 1, 2, 4, 5, 6

cell surfaces

TL 3, 7, 8, 9

Endosomal compartment of cell

TL2

Recognize teichoic acid and recognize peptidoglycan of gram positive bacteria

TL4

Recognize the lipopolysaccharide

TL5

Recognize the bacterial flagellin

TL10

Anti-inflammatory

Crohn’s Disease

Painful inflammatory disease of the bowel caused by mutations in NLRs (NOD-like receptors), NOD:
Nucleotide-binding oligomerization domain

Systemic Lupus Erythematosus

Higher concentration of antibodies to self-nucleic acids which activate dendritic cells through TLR9

Acute Phase reactants or Acute Phase proteins

Normal serum constituents that rapidly increase or decrease in concentration because of infection, injury, or trauma to the tissues.

Increase in ESR

Main biological sign of inflammation

Serum Amyloid A

C-Reactive Protein

Complement Component

Ceruloplasmin

Haptoglobin

Alpha 1 - antitrypsin

Fibrinogen

Positive APR - those that increase

Albumin

Transferrin

Negative APR - those that decrease

Hepatocytes (liver parenchymal cells) within 12 to 24 Hours

Positive APR is produced by? How many hours in response to an increase of cytokines

Pentraxins

Member of family of C-reactive protein

Tillet and Francis in 1930

C-reactive protein is discovered by?

Phosphocholine

The main substrate of C-reactive protein

C-Reactive Protein

• Most widely used as: indicator of acute inflammation

• Acts similar to antibody because it is capable opsonization (coating of foreign particles), agglutination, precipitation, and activation of complement by the classical pathway.

4-6Hours react

Within 48Hours peak value

How many hours does C-Reactive protein reacts? And the hours peak value of it

Bacterial Infection

Rheumatic fever

Viral infections

Malignant diseases

Tuberculosis

After a heart attack

Elevated levels of C-reactive proteins

<1mg/L -Low risk

1-3mg/L -Average risk

>3mg/L -High risk

0.47-1.34mg/L Normal Average

CRP low risk, average and high risk value and the normal average of CRP

56•C

30min.

CRP will easily be destroyed by heating serum to what •C and how many minutes?