PSIO Block 3 Lecture FCs

lymphatic/immune system functions

• extracellar fluid balance by returning proteins and ECF through capially exchange

• transport dietary fats w/ lympth vessles

• helps with immune response

infection immune phase (what happenes)

inflmmation, pathagen detection, immune cells activated

Resoltion Immune Phase

return back to homeostasis, anti-inflammotory

Immune Memory Immune Phase

long-lived cells created to prevent future infection

Innate Immune Response

• quick and first line of defense(physcial barrier)

• inflammtory and broad

• rising temp set point of body (fever)

adaptive immune response

• slower and trainable

• cell-mediated and antibody-mediate response

• memory, tolerance

Cells that have innate immunity

basophil, eosinophl, NK, mast

Adapative Immunity Cells

B and T Lymphocytes

basics and importance of inflammation

• triggered anytime body tissues are injured or infected

• prevents spread of damaging agents

• disposes cell debris & pathogens

• set stage for repair

cardinal signs of acute inflammation and reasons why

• heat and redness bc of increased blood flow

• swelling bc of increased peremiabiliy of capillares

• pain letting you know of that infection

structure and function of lymphatic capillaries and vessels

• lymphatic vessels filter excuss IF (protiens, cells, etc) back into the blood

• supports the different circuits and the fluid needs to be celared

how the lymph capillaries drain excess ISF and return it to the systemic
circulation

as fluid builds up, that pulls the filaments on lympth capillaries, opening them up more so substances can enter

Ly Collectors

contain values to promote unidirectional flow and are autorhymic

ly node

build up of fluid to allow immune system to filter and scan the fluid

antigen

cause antibody generation (ex: proteins, certain lipids, etc.)

immunogenicity

ability of an antigen to stimulate proliferation of specfic lymphocyte and lead to antibody production

DAMP

• released from damaged or dying cells and bind to pattern recoginzation receptors (PRR)

• ex) extracelluar ATP, Miochondrail DNA

• trigger immune responses

PAMPs

• unique to pathogens and signal the presence of infection

• ex) viral DNA or FUNA, fungal cells

• Bind to PRR leads to release of cytokines

• trigger immune responses

function of cytokines and examples

• small proteins that act as chemical messengers

• help the immune system communicate, regulate inflammation, etc.

• interleukin

• interferons

how cytokines and immune cells mediate the process of inflammation

damage = DAMPS = PRR on innate immune cells = cytokines relaseed = immune cell activation = cardianal signs

importance of interferons in disease prevention (4)

• type of cytokine

• proteins produced by NK cells, macrophges, etc

• to warn adjacent cells and alter their cellar activities(make anti-viral proteins) to prepare for the virus

• enhance innate system’s response (warning system)

functions of the complement system

• proteins produced by liver and WBCs

• helps stimulate phagocytosics, , forming membrane attack complexs (MAC) both to kill the virus

• also opsonization, which is a coating so the you eat a certain cell more (salsa)

how do natural killer (NK) cells recognize and kill virus-infected cells

• secrete perforates cell membane to allow granzymes to enter and trigger apoptosis to kill

• patrol and inspect the supace of cells throughout the body, if it doesn’t reconzie the body protein or see the cancer protein then it kills

List the body’s innate, non-specific defenses and describe the components

• physcial barries like skin, hair, etc.

• inflammatory response which prevents the spread of the damage and preps for repair

• fever, increases body set point, which increases metablolism for faster repair

• antimicorbial substances

Compare features of cell-mediated and antibody-
mediated immunity

• cell involues t-cells and focuses on intracelluar pathogens and cancer

• antibody using b-cells and focuses on extracelluar pathogens like bacteria

• helper t cells connect them both

MHC 1

found on all nucleate cells and presents intracelluar antigens. Very variable between person and person (closest with family)

MHC 2

found on all antigen presenting cells, present extracellularf antigens. little proteins outside cells that present

examples of APCs and function

• macrophage, dendtrintic cells and activated b-cells. Have both MHC proteins

• spefic cells that process and present antigens to T cells

first step of cell-mediate immunity

• antigen presentation

• MHC 2

• present either intra or extra celluar proteins

2nd step of cell-mediate immunity

• antigen reconization

• Recognize whats displayed on MHC

• don’t want it reacting to everything and CD4 and CD8 helps with specifically

• help t-cells only bind to MHC 2, and cytotoxic cells only bind to MHC 1

3rd step of cell-mediate immunity

• Antigen Activation

• naive t cell —> activated t cell

• key tasks:

  • MHC w/peptide binds to TCR

  • costimulison (if all boxes are checked then perfrom if not inactivated)

  • cytokines provide info about location and identity of pathogen

types of T cells

• cytotoxic t cells ( contain CD8) - directly kill infected cells (similar to NK cells)

• helper t cells (contian CD4 ) - regulatory function, stimulated profliferation (clonal expansion). Simlitaed by IL2

types of B cells

CD

act as a co-receptor, help with t cells

4th step of cell-mediate immunity

• PROLIFERATION: IL2 is relased from t-cells which leads to more t-cells (postive feedback loop or clonal expanstion)

• DIFFERENTATION: becomes either helper or cytotoxic t cell. If helper then it is either TH 1, 2, 17 TFH.

Last step of cell-mediate immunity

• destruction

• cytotoxic t cells search cells, that display the antigen it was told about

• to kill the cells it relases perforin to make holes that allows the granzymes to enter for apoptosis

difference between NK and cytotoxic t cells

CTL’s require that their targets are presenting antigen with MHC 1. While NK cells don’t requrie antigen presenation

specificty of lympocycte

• recombination, makes tons of variations

generation of immunocompetent

• B cells in bone marrow and T cell in thymus.

• needs to be able to interact with the body’s own cells and with MHC

lymphocyte selection

• postive selection can it bind to the MHC protein (if not you die)

• negative selection if the t-cell is “too good” at binding (if yes then die)

• if pass all tests then it goes to lymph node to wait for viruses

first 3 Steps in antibody-mediate immunity

• Presention: B-cells bind to free or floating antigens. Endocytosis & process then places on B-cell receptor

• Recoginition: antigen presented on MHC2 , helper t-cell reconization

• Acivitvation: helper t-cell dependent (peptide antigens) or independent (non peptide) not relaying on t-cells like a backup

Last 2 steps in antibody-mediate immunity

• proliferation: when activated t-cells make clones with IL2 cytokines

• diffreation: B-cells to either plasma cell (makes antibody) or memory b-cell (into bone-marrow and all long-lasting)

• IGM made by short lived and IGG made by long lived plasma cells

• destruction: NICE APE

NICE AP Meaning

• Neutralization: inactivation antigen

• Immobilization: stops antigen from being able to move

• Complement Activation: constant region helps to activate complement tract: inflmmantion

• Exchange of Phagocytois: optizamtion - antiboy makes pathogens easier to find (tag)

• Agglutination: antibodies bind to cells

• Precipitation: big block of antibodies and antigens

• Enhance inflmmation: filters

basis for “immunological memory”

5% of lympocytes wouldn’t die and stay in your system to allow for faster response the next exposure

compare cell-mediated and antibody-mediated immune
responses (4 each)

• Cell

  • intracellular responses

  • T cells (cytotoxic and helper)

  • need APC and MHC 1 or 2

  • direct kill

• Antibody

  • extracellular

  • B cells (memory and plasma)

  • use MHC 2 and helper t cell

  • indirect by releasing antibodies to fight pathogen

cells and processes that contribute to the resolution phase

• helper t cells will produce anti-inflammotry cytokines

• Resolvins: stop neutrophil requirtment and reduce inflammation and M1 to M2 which are pro repaire

general structure of an antibody

• Variable region (top): where antigen binds

• Constant region: determines class (IGG)

Compare different types of acquired immunity

• Natural

  • active: expose of pathogen

  • passive: antibodies from mom

• Artificially

  • active: vaccine

  • passive: injection with immune serum