Immuno exam

what makes up innate immunity

PAMPs, DAMPs, PRRs, cytokines, TLRs

what makes up Adaptive immunity

lymphocytes, humoral and cell mediated responses

what is innate immunity

nonspecific, rely on IgG, acts within minuets

what is adaptive immunity

builds memory, rely on IgM, antigenic specific reponse

Layers of defense

physical barrier (skin, mucous), secretory barrier (lysozymes, normal flora), physiological barrier (fever, gastric acid)

PAMPs

Pathogen associated molecular patters

part of the innate immune system

includes viral DNA, flagella etc

DAMPs

AKA alarmins, released from stress cells (necrotic)

part of innate immunity

PRRs

pattern recognition factor that recognizes PAMPs and DAMPs which triggers the innate defense

inflammatory cytokines

IL-1

IL-6

TNF- alpha

IL-8

senteniel cells

macrophages, neutrophils, mast cells, dendritic cells

2 arms of adaptive immunity

humoral

cell mediates

humoral adaptive immunity

EXTRAcellular (bacteria, parasites)

use antibodies to neutralize, opsonize etc

cell mediated adaptive immunity

INTRAcellular, recognize viruses

use CD8 cells to directly kill infected cells

lymphocytes to know

B cells- differentiate into plasma cells which produce memory cells

T cells- CD4, CD8, Th 17, Treg

Th 17 lymphocyte

a t helper cell that helps with inflammation in mucosal surfaces

bacteria and fungal defense

Treg lymphocyte

stops inflammation when infection is cleared and prevents autoimmunity

Primary v secondary response

primary- innate acts faster than adaptive, longer lag, memory B and T cells are generated, IgM predominant

secondary- adaptive acts faster, shorter lag, IgG predominant

what causes a cytokine storm

LPS, TLR4

often in septic neonates or post surgical complications

multiorgan failure

primary lymphoid organ role

lymphocyte maturation and generation

do not need an antigen at this stage

primary lymphoid organ example

thymus, bursa (birds), bone marrow, peyer patches (ruminants)

if removed can cause lifelong issues

secondary lymphoid organ role

where the antigen encounters the lymphoid, site of immune response

secondary lymphoid organ example

lymph nodes, spleen, MALT

require an antigen

if removed patient will be ok

what is thymic education

positive- cells with affinity for self-MHC survive (T cells only)

negative-self reactive cells are deleted (T and B cells cells)

what is thymic involution

when the thymus begins to shrink- during puberty

Illeal Peyers patches

primary lymphoid organ

2 “species”

Group 1- in ruminants

Group 2- acts as secondary lymphoid in primates, rabbits and rodents

what is MALT

mucosa-associated lymphoid tissue

activate B cells to produce IgA

what happens if you remove the spleen

secondary lymphoid organ

loose blood filtering capability

compliment system

part of the innate immune system, can be activated in 2 ways

classical- when an antigen attaches to an antibody (bridges adaptive and innate)

alternative- when a pathogen invades

what is significant about C3

C3a- triggers inflammation

C3b- triggers opsonization

C3b complex- triggers MAC attack and lyses cells

what are polymorphonuclear granulocytes

eosinophils, neutrophils, basophils

what are mononuclear granulocytes

monocytes, lymphocytes

how does phagocytosis work

pathogen is engulfed with a phagosome, lysozome binds to digest pathogen, pathogen is digested to antigen, antigen is presented on MHC

professional phagocyte

macrophage, neutrophil

what is opsinization

when an antibody completely coats a pathogen to allow it to stick to a cell surface receptor

neutrophil surface receptors

integrins, compliment receptors CRs, antibody receptors FcR, PRRs

2 ways neutrophils work

NETS (if too big for phagocytosis)

phagocytosis (use reactive oxygen species)

macrophage of the skion

langerhan cells

macrophage of the liver

kupfffer cellsm

M1 macrophage

macrophage that use phagocytosis, secrete inflammation cytokines

M2 macrophages

trigger wound healing and regeneration, secrete anti-inflammatory cytokines

professional APC

dendritic cells, B cells, Macrophages

what are granulomas

type of wall to block foreign object from being continuously attacked by the immune system if it cannot be removed (ex tattoo ink)

what is pus?

dead neutrophils

acute inflammation

a response to harmful stimuli to eliminate pathogens

triggers of acute inflammation

PAMPs, DAMPs etc

cardinal signs of inflammation

redness, heat, swelling, pain

what are CAMs

proteins on the cell surface that bind APC to lymphocytes

they get lymphocytes out of the blood and into infected tissue

local effects of inflammation

increased blood flow, vascular permiability, increased expression of CAMs, inflammatory cytokine production

systemic effetcs of inflammation

fever, anorexia, lethargy, shock

how is inflammation terminated

anti-inflammatory cytokines (IL-10, TGF-beta), apoptosis of inflammation cells, short life of inflammatory mediators

chronic inflammation

due to infectious and noninfectious causes (cancer, autoimmune, obesity)

how to differentiate between lymphocyte populations

use flow cytometry to detect fluorescent labled antibodies bound to the surface receptors

what do B cells make

plasma cells which can make memory B cells and antibodies

what do T cells make

CD4, CD8, treg, memory cells

what do BCR and TCR recognize

antigens

what do MHC receptors do

present antigen to Th cells

2 T cell subpopulations

alpha/beta

gamma/delta

alpha/beta T cells

recognize antigen on MHC and express CD4 (MHC 2) or CD8 (MHC 1)

gamma/delta T cells

recognize free floating antigen and use perforins/granzymes to kill cells

example of CAMs

integrins, selectins

positive cytokine receptor

turns on gene expression in the nucleus

negative cytokine receptor

turns off cytokine action

How is a cytokine different from hormone

hormone signals to specific endocrine cells via endocrine signaling, cytokines signal to many kinds of cells via autocrine, paracrine and endocrine signaling

pleitropic cytokine

one cytokine can adhere to many cell types and cause different responses in those cells

redundant cytokine

multiple cytokines adhere to different cells but cause the same response

what is an interleukin

Type of cytokine

lymph to leukocyte interaction (IL)

what is an interferon

Type of cytokine

antiviral cytokine produced in reponse to a viral infection (INF)

what is a tumor necrosis factor

Type of cytokine

anti-tumor cytokine (TNF)

what is a growth factor

Type of cytokine

regulate stem cells and hematapoiesis

what is a chemokine

Type of cytokine

chemotaxis of immune cells

how are cytokines regulated

1- change receptor proteins on target cells to block cytokine binding

2- bind other proteins to block cytokines from acting

3- use negative cytokines to turn off function in cell

what are some specific cytokine effects

mediate innate immunity

regulate lymphocyte growth

activate inflammatory cells

what is EPO

a cytokine that specifically produces RBC

what is G-CSF

a cytokine that specifically produces neutrophils

what is IL-2

a cytokine that specifically stimulates lymphocyte production

what is dangerous about IL-6

IL-6 acts on both innate and adaptive immunity. Its soluble receptor allows IL-6 to signal in cells that do not express the membrane-bound IL-6 receptor, giving it a broader range of targets.

can lead to cancer/covid

what is an MHC haplotype

a specific combination of MHC 1,2,3 genes that are all carried on one chromosome and influence disease resistance etc

What is polygeny

multiple MHC genes within a cells DNA that can produce multiple types of MHC due to the different types in DNA

what is polymorphism

diversity of MHC genes between cells

what is codominance

express both parent MHC genes to expand immune coverage. Heterozygous advantage

what is promiscuous binding

one MHC can present many antigens and peptides

where is MHC1 found

on most nucleated cells, made up of 2 chains (alpha, beta-2-microglobin)

what is MHC1 recognized by

CD8 cells, lack of MHC 1 means the NK cells will kill it

where is MHC2 found

on APC cells, presents proteins from outside of the cell, made up of 2 chains (alpha, beta)

what is MHC2 recognized by

CD 4 cells

What is MHC 3

not an ag receptor, rather codes for compliment proteins, cytokines, stress hormones

Antigen vs Immunogen

an ag CAN induce an immune response, but an immunogen WILL induce an immune response

what is an epitope

region of an ag recognized by an ab. can be linear or conformational

linear- linear sequence of amino acids preserved after denaturation (recognized by TCR and MHC)
conformational- folded sequence lost after denaturation (recognized by BCR and antibodies)

isotype

differences between antibody classes (IgG vs IgM)

Allotype

same ab class but seperate ab

idiotype

unique features associated with an antibodies ag binding region

antibody structure

made up of 2 chains -light and heavy

both the light and the heavy chain have a variable (Fab) and a constant (Fc) region

ex Fc VH- the constant region on the heavy chain

where do the antigens bind to on the antibody

on the ag binding site which is made up of heavy and light variable regions

IgM

main

innate immunity, is a pentameter, helps with agglutination

IgG

secondary

adaptive immunity, is a monomer, helps with opsonization

IgA

mucousal anitbody, is a monomer/dimer

has SIgA (secretory) to protect it from digestion

IgE

allergies, a monomer, on mast cells and basophils bc it deals with histamine

IgD

developing, in naive B cells, monomer

what is an immunoglobin superfamily

a group of proteins that share a similar structural feature (not all ab)

what is affinity

the strength of an individual bond