PSL 301 Term test 1 (blood and Immunity)

plasma

fluid portion of blood 46-63% of total blood volume

hematocrit

% of total blood volume occupied by packed (centrifuged) red blood cells. normal range (37-54%)

plasma proteins

made in the liver; albumin, globulins, fibrinogen, transferrin.

Generate colloid osmotic pressure and buffer pH.

albumin

Contributes to colloid osmotic pressure; carrier of various substances. Makes up 60% of plasma proteins.

globulins

Clotting factors and enzymes(alpha and ß); antibodies (immunoglobulin (gamma); secreted by specialized blood cells); carriers of various substances. Makes up 35% of plasma proteins.

fibrinogen

cleaved to form fibrin threads essential for clotting. Makes up 4% of plasma proteins.

transferrin

iron transport. Makes up 1% of plasma proteins.

colloid osmotic pressure

The presence of proteins in the plasma creates a pressure gradient across capillaries. This allows for the flow of water into the capillaries from the interstitial fluid.

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Pcap > Pif

Formed elements

Cellular components of blood. 3 main types


1. Erythrocytes
2. Leukocytes
3. Thrombocytes

Erythrocytes

Red blood cells; make up 99.9% of formed elements.

Leukocytes

White blood cells; make up 0.1% of formed elements. 5 types can differentiate.

Thrombocytes

platelets; critical for blood clotting

Differential white count

gives the relative percentage of white blood cell types in blood.

Lymphocyte

White blood cell; required for acquired immune response. Makes up 20-40% of D.W.C.

Monocyte

white blood cell; parent cell of tissue macrophages. Makes up 2-8% of DWC.

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Phagocyte

Neutrophil

White blood cells that ingest pathogens and release cytokines. Makes up 50-70% of DWC.

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First sign of infection

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Phagocyte and Granulocyte

Eosinophils

white blood cells; associated with parasitic infections and allergic reactions. Makes up 1-4% of DWC.

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Granulocyte

Basophils

white blood cells that secrete histamine. Makes up

phagocytes

immune cells that engulf anything foreign

granulocytes

general appearance of cell

Red blood cells

Biconcave disk shape; bags of hemoglobin and enzymes

\~5million per micro-litre of blood

Hemoglobin

two chains:

* alpha x2
* beta x2

4 heme groups = 4 iron atoms = capacity to bind to 4 oxygen atoms.

120

the lifespan of RBC’s is about _____ days.

Pluripotent stem cells

Cells that have the ability to develop into many different cell types.

bone marrow

Where are blood cells derived from? - in adults

* pelvis
* spine
* ribs
* cranium
* proximal end long bones

Erythropoiesis

production of red blood cells

Erythropoietin

hormone made in kidney that leads to the production of RBC’s.

erythrocytes; leukocytes

in bone marrow: 25% _______; 75%__ _______

megakaryocyte

platelet precursor

cytokines

_______ regulate hematopoiesis

colony stimulating factors

_______ are from endothelial cells and white blood cells

interleukins

_______ are from white blood cells

site of hemopoiesis

yolk sac, liver, spleen, and bone marrow - in embryo

jaundice

Hyperbilirubinaemia

* high turnover of RBC
* Liver disease
* Bile duct obstruction

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anemia

low production of RBC’s; low hematocrit

aplastic anemia

destruction of stem cells via drugs and radiation

nutritional/ pernicious anemia

Inadequate iron, folic acid, vitamin B12

renal anemia

low erythropoietin (potential result of kidney failure)

Hemorrhagic anemia

excessive blood loss (high removal)

hemolytic anemia

high removal of RBC’s

* genetic (defects in RBC’s)
* parasitic infections
* Drugs (antibiotics and anti seizure drugs)
* autoimmune reactions

polycythemia

hematocrit too high (>\~54%)

* high blood viscostity

high production; low removal

primary

abnormal erythrocyte precursors (polycythemia)

secondary

low oxygen delivery to tissues (kidney = increased erythropoiesis) (polycythemia)

pathogens

what do parasitic worms, fungi, protozoa, bacteria, and viruses have in common.

Meningitis

The following symptoms are a sign of what condition?

* fever/vomiting
* severe headache
* stiff neck
* dislike of bright light
* very sleepy/vacant/difficult to wake
* confused/delirious
* rash
* seizures

bacterial meningitis

Neisseria menigitidis (meningococcus)

innate immunity

rapid and non-specific defence against pathogens.

acquired immunity

slower and specific defence against pathogens

tonsils

_______ are a diffuse lymphoid tissue.

lymph nodes/ spleen

Encapsulated lymphoid tissue

thymus

produces T lymphocytes

GALT

Diffuse lymphoid tissue of the gut

lymphatic system

3 key functions:


1. return excess tissue fluid to the blood
2. Transport pathogens/ dendritic cells to lymph nodes
3. Transport fat from digestive system to the blood

lymph nodes

________ monitors lymph fluid. Contains mature immune cells that interact with pathogens and initiate an immune response.

Spleen

________ monitors blood. Contains mature immune cells that interact with pathogens and initiate an immune response.

B lymphocytes

make antibodies; found in blood, lymph and tissues

T lymphocytes

Acquired immune cells; found in blood, lymph and tissues

Natural killer cells

innate immune cells; found in blood, lymph, and tissues

macrophages

phagocytose pathogens

dendritic cells

take up pathogens; part of innate immune response

Mast cells

develop first from bone marrow

physical barrier

Part of the innate immune system; skin and mucous membranes.

* epithelium
* glandular secretions
* stomach acidity
* mechanical removal

epithelium

the protective barrier of skin and mucous membranes is the body’s first line of defence.

glandular secretions

used to trap and disable pathogens

ex. mucus, antibodies, and enzymes

stomach

the low pH of the _______ helps destroy swallowed pathogens

mechanical removal

* mucociliary escalator
* tears
* coughing, sneezing
* Gi mobility

Phagocytes

part of the body’s innate immune response

3 types:


1. neutrophils
2. macrophages
3. monocytes

diapedesis (extravasation)

when the cell moves into tissue with the infection

chemotaxins

bacterial toxins, products of tissue injury, cytokines

toll-like receptors

binds to a series of different structures on pathogens to identify foreign species.

anti-body receptors

binds to bacteria that have been opsonized

opsonin

an antibody or other substance which binds to foreign microorganisms or cells making them more susceptible to phagocytosis

antigen fragments

macrophages and dendritic cells display _______ on class II MHC.

natural killer cells

kill cells when they are infected by a virus or are cancerous. part of innate immune response.

2; MHC class I

normal cells have a total of ____ transmembrane proteins to be read by the natural killer cells. One is an activator ligand, and the other is a *-*_-_-_-_

reduced

the natural killer cells can recognize a virally infected cell or cancerous cell by the _____ expression of the MHC class I protein.

interferon

a protein released by animal cells, usually in response to the entry of a virus. (innate immune response)

cytokines

when a natural killer cell senses the reduced MHC class I on the target cell this results in the release of ______.

alpha and beta

interferons that prevent viral replication in cells

gamma

Interferons that activate macrophages and other immune cells. (Stimulate innate immune response)

complement

antimicrobial proteins that:

* destroy target cell membranes
* stimulate inflammation
* attract phagocytes
* enhance phagocytosis

classical pathway

One of three ways to activate complement.

* antigen- antibody complex

lectin pathway

One of three ways to activate complement.

* Microorganisms cell wall polysaccharide

Alternative pathway

no inhibitors on microbe surface

C3b

product of C3 being cleaved that leads to opsonization

C3a

product of C3 being cleaved that causes inflammation

membrane attack complex

complement process:

what do the following factors all lead to?

C5b, C6, C7, C8, C9

inflammation

Localized tissue response to injury producing swelling, redness, heat and pain

function of inflammation

* slowing the spread of pathogens
* mobilization of local, regional, and systemic defences
* sets the stage for repair

dilation

the _____ of blood vessels allow antibodies, complement, kinin, clotting factors to move into interstitial tissue.

bradykinin

vasodilator and stimulates pain receptors. Formed by the kinin cascade.

fever

the function of a ______ is to speed up metabolic activity of host; inhibit some pathogens.

37\.2

body temp >____ degrees is considered a fever

pyrogens

bacterial components, interleukin-1 released from activated macrophages. _______ change the thermoregulatory set point in the hypothalamus.

specificity

Features of acquired immune system:

* activated by and responds to a specific antigen

versatility

features of acquired immune system:

* ready to confront any antigen at anytime

memory

features of acquired immune system:

* “remembers” any antigen at anytime

tolerance

features of acquired immune system:

* responds to foreign substances but ignores normal (self) tissues

antigen

small part of pathogen

antibody

binds to antigen