Medical Immunology Antigens and Antigen Recognition

What are characteristics of the innate immune response?

Functional at birth, nonspecific, immediate response, no memory cells

Which immune response is functional at birth?

Innate

Which immune response is nonspecific?

Innate

Which immune response is immediate?

Innate

Which immune response is not improved with repeated exposure?

Innate

Which immune response develops six months after birth?

Adaptive

Which immune response requires exposure to pathogen?

Adaptive

Which immune response increases in strength after each re-infection?

Adaptive

Which immune response produces memory cells?

Adaptive

Which immune response produces antibodies?

Adaptive

Which immune response contains B-cells, CD4 T-cells, and CD8 T-cells?

Adaptive

What are CD4 cells?

Helper T-cells

What are CD8 cells?

Cytotoxic T-cells

What characteristics are specific to the adaptive immune response?

Develops six months after birth, increases strength after each re-infection, requires exposure to work

Cells of the adaptive immune response

B cells, CD4+ (Helper) T lymphocytes, CD8+ (Killer/cytotoxic) T-lymphocytes

Innate Immune response cells

Macrophages, mast cells, granulocytes, natural killer cells

Which immune response are macrophages part of?

Innate

Which immune response are mast cells part of?

Innate

Which immune response are granulocytes part of?

Innate

Which immune response are NK cells part of?

Innate

Barriers and reflexes of the innate immune response

fever, cough reflex, pH, skin, cilia, mucosa and mucous

Proteins of the innate immune response

Complement, cytokines, lysozyme, defensins

Chemicals of the innate immune response

histamine, prostaglandins, leukotrienes, cytokines

What is an antigen?

Anything that elicits an immune response

What are PAMPs?

Pathogen associated molecular patterns; molecules that are unique or foreign to the host organism, making it easier to detect antigens

What are epitopes?

Functional groups on antigens that are specifically recognized by receptors on immune cells

What are haptens?

Small molecules which do not generate an immune response by themselves but can lead to a reaction when bound to a target cell

What cells possess antigen/microbial sensors?

Phagocytes

What is another name for microbial sensors?

Pattern recognition receptors

What are the three major groups of microbial sensors?

Toll-like receptors, NOD-like receptors, and RIG-1-like helicases and melanoma differentiation gene 5

What are Toll-like receptors?

Evolutionary conserved PRRs, surface and endosomal proteins

Where are TLRs found?

On phagocytes, dendrites, and B-cells

What does TLR2 recognize?

Bacterial peptidoglycan

What does TLR4 recognize?

LPS

What does TLR5 recognize?

Bacterial flagellin

What do endosomal TLRs recognize?

RNA and DNA

What do endosomal TLRs protect against?

Intracellular pathogens such as viruses, worms, and some bacteria

What does TLR3 recognize?

dsRNA

What does TLR7 and TLR8 recognize?

ssRNA

What does TLR9 recognize?

CpG DNA

What happens when TLRs bind to an antigen?

They activate genes for anti-bacterial or anti-viral proteins.

How do TLRs activate antiviral/bacterial genes?

By activating a series of proteins that converge to activate the NFkB transcription factor which activates the genes

What are NOD-like receptors?

Cytosolic receptors that detect pathogens and stress signals

What do NOD 1 and 2 recognize?

Bacteria and bacterial toxins

What happens when bacteria bind to NOD receptors?

RIP2 kinase is activated which activates NFkB