Immunology PT2 - immune cells cont. antibodies, adaptive immunity

IgM

IgG

most abundant, crosses the placenta

IgA

dimer, found in breast milk, tears, saliva and mucus membranes

IgE

allergy and parasite response, mast cells and T1 hypersensitivity

IgD

B cell activator, relatively uncommon

IgM

pentamer, first antibody released

What are the main functions of the constant region of an antibody?

activate the classical complement pathway, bind to Fc receptors on macrophages, mast cells, neutrophils and NK cells, bind to molecules that transport antibodies across epithelial surfaces

How are antibody expressions regulated?

Cytokines

Which antibodies are monomers?

IgD, IgE, IgG

Which antibodies are dimers?

IgA

Which antibodies are pentamers?

IgM

What are the functions of antibodies?

opsonization, neutralization of pathogens and toxins, complement activation

Refers to the strength of a single antibody-antigen interaction, high in IgG binding sites

affinity

Refers to the strength of all interactions combined, typically high in IgM

avidity

What is the cellular response to a parasitic infection?

Mast cells attract eosinophils, cause muscle spams to expel parasites. Eosinophils secrete granules to punch holes in worms cuticle. Basophils involved in Th2 response

Large, multi-nucleated cells that digest foreign bodies

macrophages

The macrophages that remove cells and debris, typically without inducing inflammation

resident macrophages

Activated macrophage that is microbicidal and pro-inflammatory

M1

Activated macrophage that is immunomodulatory and poorly microbicidal

M2

What do macrophages have on their surfaces to detect PAMPs and DAMPs?

Toll-like receptors

Which complement proteins form the MAC?

C5B, C6, C7, C8, C9

Which cytokine is made by both plants and animals to help kill pathogens?

Defensin

What is a pathway cancer can exploit to stop T cells from detecting pathogens?

CTLA-4

What percentage of IgG transfers to dogs and cats via the pacenta?

5-10 percent

When compared to adults, innate immunity in newborns have…

weaker opsonic ability and similar phagocytic ability

Why is it so important for ruminants to nurse within 24 hours?

Their gut is unable to absorb antibodies after 24 hours and they do not receive immunoglobulins from placenta

Why is it not advised to vaccinate very young animals

Maternal Antibody interference

What antibody arrives first and activates the classical complement pathway?

IgM

Which antibody is primarily in the respiratory and GI tract? Which IL stimulates it?

IgA, IL-5

What stimulates the production of eosinophils during an infection involving IgE?

Th2 cells along with IL-5

How are antibody/antigen complexes removed when the pathogen has been neutralized?

Complement breaks down and fragments are carrier way on red blood cells where they are transferred via FcR and CR1 on macrophages to be phagocytized

What receptors is upregulated during inflammation and binds to IgE antibodies

FceRI