PHYL142 Lymphatic & Immune Systems

filtration

movement of fluid INTO tissues due to blood (HYDROSTATIC PRESSURE) NFP>0 +

Reabsorption

movement of fluid BACK INTO VESSELS due to oncotic and osmotic pressure NFP< 0 -

lymphatic system

Slightly more fluid leaves blood vessels than is reabsorbed and leftover fluid is brought back via the ____

lymph

Very similar to plasma + Does not have plasma proteins (large proteins like ALBUMIN stay in blood) but water, sugar, salts & small molecules ca flow through small pores or clefts

endothelial cell flaps

lymphatics are a one way street, large particles & immune cells can move through overlapping _____ ___ ___

Smooth muscles

Lymphatics allows fluids & cells in but not back out (~1 mm Hg at rest) ____ ___ contracts to move fluids and lymphatics return fluids back into the CV system

right subclavian vein

The right lymphatic duct drains into the

left subclavian vein

The Thoracic ducts drains into the ____

lymphedema

sweling caused by lymphatic blockage

T cells (80%), B cells (10-15%), NK cells (5-10%)

What are the subdivided classes of lymphocytes?

Cytotoxic, Helper, Suppressor, Memory T cells

What do T cells differeentiate into?

Cytoxic

____ T cells attack foreign cells or body cells infected by viruses

Helper

__ T cells stimulate the activation and function of both T and B cells

Suppressor

_____ T cells inhibit the activation and function of both T cells and B cells

Memory

______ T cells are a subset of T cells that respond to a previously encountered antigen

Plasma cells

When stimulated B cells can differentiate into ____ ___ which produce and secrete antibodies

NK cells

___ ____ make up the remaining 5-10% of circulating lymphocytes

capsule (collagen fibers), Cortex (outer B, deep T), Medulla (B cells)

The structure of a lymph node consists of

Filtering and protection against pathogens and helps immune systems

Function of the lymph node:

Lymphadenopathy

Abnormal swelling of lymph nodes

Bubo

Swollen lymph node

The immune system

System of molecules, cells, tissues, and organs that protect the body from foreign and pathogenic substances, cells, and organisms

pathogen

something that causes disease

Innate immunity

Nonspecific protection against pathogens but particularly defenses you’re born with

Adaptive immunity

defenses against NEW pathogens you encounter

physical barriers, phagocytes, complement, inflammation, fever, immune surveillance, interferons

what are some innate defenses

skin, mucosae, secretions —mucus, tears, sweat,

What are some physical barriers used to protect you from pathogens

defensins

mucus secretions have ___ which are antimicrobial proteins

Lysozyme

Tear secretions have ___ which is a antibacterial enzyme and surfactants

Traps & impedes pathogen entry and neutralizes pathogens

What does mucus do

Glycoproteins,Thickened extracellular fluid , Retain water, Slow & impede pathogen movement

Important features of mucins

Acidic pH, High [salt]; hypertonic to microbes, defensins – antimicrobial proteins dermicidin – antimicrobial protease enzyme

Features of sweat against microbes

Hydrochloric acid (HCl), denatures proteins, dissolves microbes pr inhibits growht

Gastric acid defenses against microbes

human microbiota

The ______ _______ makes it difficult for pathogens to develop, as it secretes or produces chemicals that impede pathogenic bacteria— Crowd out other bacteria meaning competition

phagocytes

broad category of cells that engulfs and “eats” things (debris, pathogens, dead cells) neutrophils, macrophages, monocytes, esinophils….

Monocytes

Type of leukocyte that can become macrophages, a phagocyte and is highly mobile throughout bloodstream & tissues

Macrophages

Mature monocytes, is phagocytic, recruits neutrophils and causes inflammation

stationary

Fixed macrophages

mobile

free macrophages

Chemotaxis

movement of cell toward (or away from) a chemical

e.g. bacteria & damaged cells release chemicals & proteins, immune cells detect chemotactic chemicals, esp. phagocytes

diapedesis

Passage of blood cells through capillary walls

Complement

Class of proteins found in your blood that help with immunity

liver

Complement is mostly produced by the ____, always circulating;remaining inactive if not needed, and is activated pathogens

recruits macrophages + activates mast cell degranulation

How does Complement help immune cells

pathogenic cells

Complement can also attack _______ ___ by itself

adaptive immune

Antibodies are part of the _____ ___ response

Interferon alpha

This interferon is produced by cells infected with viruses. It attracts and stimulates NK cells and enhances resistance to viral infection

Interferon Beta

This interferon is secreted by fibroblasts and slows inflammation in a damaged area—can be ether anti-inflammatory or pro-inflammatory depending on multiple factors

Interferon gamma

This interferon is secreted by T cells adn NK cells and stimulates macrophage activity

Interferons

Increases: anti-viral defenses, DNA repair, MHC-I & MHC-II presentation, NK cell activity, destruction of infected cells

Inflammation

Macrophages, neutrophils & other immune cells release chemicals that cause ____

repair

Inflammation is a bodily response to injury or disease in which heat, redness, and swelling occur, to eliminate harmful substances and ____ damaged tissue

heat

calor

suffering, pain

dolor

Redness

rubor

tumor

swelling

Mast cells

these cells release histamine

vasodilation

Histamine causes ___

Histamine (IgE)

______ increases vessel permeability making sure immune cells can move out of the vessels easier, increased fluids also leak which could lead to heat, redness, & swelling

Fever

simpler term for pyrexia or febrile response

pyrogens

For a fever, bacteria and immune cells can release ____

pyrogens

chemicals that cause the body to produce more heat

metabolism

Fevers add energy & speed up _____ in immune cells

bacteria

Fevers make the body inhospitable for foreign ____

37.0C (98.6 F)

“Normal“ or average adult body temp

< 35 C (95F)

Temperature for hypothermia

> 38 C (100.4F)

temperature for a fever

> 40 C (104 F)

Temperature for hyperpyrexia

Antipyretics

Non-steroidal anti-inflammatory drugs (NSAIDS)

aspirin, ibuprofen, naxprofen

Examples of some NSAIDs

Age (high in children), Sex (higher in females), Time of day (increases during the day)

What are things that can affect your normal temp

36 to 37.5 C (96.8-99.5F)

what is the normal range for body temp?

neutrophils

This phagocyte promotes inflammation & recruits other immune cells, forming web-like fibrous NETs (neutrophil extracellular traps), and degranulation

Degranulation

The release of toxic chemicals from cellular vesicles (granules) like defensins, enzymes that produce free radicals, enzymes that degrade extracellular matrices and these chemicals are also toxic to regular cells

Pus

Thick, opaque fluid resulting from inflammation or infection

Protein, Pathogen remnants, Cell & tissue debris, Dead WBCs

What does pus contain

Leukocyte extravasation

The movement of WBCs from the bloodstream → tissues

Diapedesis

The passage of blood cells through capillary walls

Granulocytes

_____ release inflammatory molecules that include mast cells & basophils w/ granules that contain histamine & heparin to cause inflammation

Heparin

An anticoagulant

Histamine

Increases vasodilation & vessel permeability

INCREASED Vessel diameter & permeability

During anaphylaxis, histamine release does what?

increased blood flow

With increased vessel diameter, blood flow is

increased immune cell movement and increased vessel to tissue fluid exchange

With increased permability there will be

Increased head, redness & swelling will happen

With increased fluid movement….

inflammatory cytokinesis

Endogenous example for pyrogens

bacterial cell wall components

Exogenous example of pyrogens

Defensins, enzymes that enhance lysozyme & phagocytosis, free radical enzymes (peroxidases), and collagenases

What do granule contents include

Defensins

______ are antimicrobial proteins

Natural Killer Cells (NK)

These cells are innate immune cells that recognize abnormal cells causing apoptosis in those abnormal/infected cells

Major Histocompatibility Complex Class I (MHC-I) receptors

All Cells with a nucleus have ____ _____ ___ ___ _ receptors. All cells display their own proteins on these receptors.

MHC-I

______ receptors help your cells recognize each other

inspect

NK cells ____ MHC-I receptors, if everything is normal nothing happens

Infected

______ cells lack MHC-I receptors— NK cells will cause infected cell to die

Tumor cells

____ may have MHC-I receptors but NK cells can also detect abnromal surface molecules, NK cells will kill any “unusual” cell in your body

MHC-1 & MHC-II receptors

_____- &_____ ID your cells to your immune system

Human Leukocyte Antigens (HLAs)

____ typing tries to match organ & tissue donors & recipients with genetically similar MHC-I & MHC-II

Innate Immune Response

Immune responses already “pre-installed” in your body

Pathogen

Your innate immune response recognize common ____ properties (e.g. bacterial, viral, fungale molecules, things that don’t belong in your body) Its Fast, but less accurate and Cant recognize EVERY pathogen

Adaptive immune response

Your genes do not have defenses against all pathogens, How your body learns to attack new foreign molecules & pathogens.