MicroBio 8/16/2022

Interferon alpha and beta are produced by

lymphocytes, epithelial cells, fibroblasts

Interferon alpha and inhibit

viral replication, activate NK cells

TNF-alpha

promotes inflammation via activated macrophages, also activates t-cells

TNF-alpha can be harmful by inducing

septic shock

Besides promoting inflammation, TNF-alpha also induces

fever

IL-1 is related to TNF-alpha because of its ability to

induce fever

Secreted antibody is mainly found in

plasma/serum

How is the light chain attached to the heavy chain?

disulfide bond

T/F there are two identical light chains and two identical heavy chains in the Ig structure

true

What gives the Ig its flexibility?

Hinge region

The antigen-binding site of the antibody is...

variable region

what does the constant region of the Ig does

mediate effector functions(compliment activation and binding IgG Fc receptors)

___ digestion cleaves ___ at the ___ region

Papain, IgG, hinge

___ digestion cleaves ___ below the ___ region

Pepsin, IgG, hinge

T/F B cells have genetic recombination to produce antibodies

true

Each antibody molecule has either

kappa or lamba chains

How many classes of light chains can a cell make?

1

IgM in the circulation exists as a

pentameric molecule

IgM has a high __ capacity

agglutinating

IgG works by

opsonization of antigens (higher affinity)

IgA serum circulates as

monomers

Secretory IgA

is in fluids, important against mucosal infections

Secretory IgA also contains a ______ which increases resistant to proteolytic cleavage

secretory chain

IgE is found...

on the surface of mast cells and basophils

IgE is important in fighting

parasites and allergies

isotopic variation

Ig classes and subclasses

allotypiic variation

variation of an isotope within a species (IgG vs IgG)

Idiotypic variation

antigenic diversity and specificity of the antigen binding site

5 effectors functions of antibodies are

1. neutralization2. complement fixation3. agglutination4. opsonization5.antibody-dependent cell-mediated cytotoxicity

TCR recognizes

membrane-associated antigens and linear determinants

For a T-cell to work, the antigen would need the ___ complex

MHC

T/F t-cell and b-cells recognize protein antigens only

false, b cell also does Nucleic acids, chemicals, etc

What cells express MHC class I?

all nucleated cells

What cells express MHC II?

T cells, B cells, dendritic cells, macrophages, epithelial cells of the thymus.