Post on 17-Jan-2018
description
(White Blood Cells)(White Blood Cells)
LeucocytesLeucocytes
Specific – 3rd line
Non- specific – 2nd line
Blood films – Romanowsky stainBlood films – Romanowsky stain
Red Blood Cells Eosinophil
LymphocyteBasophil
Neutrophil
Macrophage
Lymphocytes - TypesLymphocytes - Types
B cellsB cells
MemoryMemory Plasma PlasmaBBMM BBPP
T cellsT cells
HelperHelper Cytotoxic CytotoxicTTHH TTCC
Immunity WordsImmunity Words AntigenAntigen – causes an – causes an
immune response immune response (usually a pathogen)(usually a pathogen)
AntibodyAntibody – protein – protein produced by B cells to produced by B cells to destroy specific destroy specific antigensantigens
B cellsB cellsResponsible for Responsible for Humoral Immunity Humoral Immunity
Produces Produces antibodiesantibodies which circulate in the which circulate in the blood and destroy specific antigensblood and destroy specific antigens
Usually effective against pathogens that do Usually effective against pathogens that do not invade cells (eg, bacteria)not invade cells (eg, bacteria)
B cellsB cellsMemory cells Memory cells
Survive for many years (decades)Survive for many years (decades) ‘‘Remember’ how to make antibodies to a Remember’ how to make antibodies to a
specific disease so that if re-infection occurs, specific disease so that if re-infection occurs, immune reaction is quickerimmune reaction is quicker
Plasma cellsPlasma cellsAntibody factoriesAntibody factoriesProduce a specific type of antibodyProduce a specific type of antibodyHave a shorter life span than memory cellsHave a shorter life span than memory cells
T cellsT cellsResponsible for Responsible for Cell-mediated immunityCell-mediated immunity
Destroys cells of the body that have been Destroys cells of the body that have been invaded by specific pathogensinvaded by specific pathogens
Destroy cells mainly by Destroy cells mainly by phagocytosisphagocytosis or or ‘eating’ them and also by activating other ‘eating’ them and also by activating other immune cellsimmune cells
T cellsT cellsCytotoxic T cells (TCytotoxic T cells (TCC or T or TKK) )
Kill cells that contain an antigenKill cells that contain an antigenGenerally kill intracellular pathogens such as Generally kill intracellular pathogens such as
virusesviruses
Helper T Cells (THelper T Cells (THH))Activate other T cells and B cells by releasing Activate other T cells and B cells by releasing
chemical messengers called lymphokineschemical messengers called lymphokinesTriggers white cell replication by releasing Triggers white cell replication by releasing
cytokinescytokines
The Immune ResponseThe Immune Response
B
Y
Y
Y
Y B
I
I
I
I B
I
I
I
IThere are many different types of B cells in our blood which have receptors on their surface that can recognise many different types of antigens
Pathogens produce specific antigens
B
I
II
I
The antigen will bind to the appropriate B cell, triggering an immune response
Monoclonal SelectionMonoclonal Selection
B
I
I
I
I
B
I
I
I
IB
I
II
I
B
I
I
I
I
B
I
I
I
I B
I
I
I
I
B
I
I
I
IB
I
I
I
I
II
I
III
I
I
I
I
I
I
I
I
I
I
I
B
I
I
I
I
Plasma Cells
Memory Cells
B
I
I
I
IAntibody
production
Proliferation
AntibodiesAntibodies
Antibodies bind to antigens and destroy them by puncturing them and attracting phagocytes and T cells to them
Lymphocyte interactionLymphocyte interaction
Antigen
B TH TC
TH TH
BM BP I
ITC TC
Chemical Activation
Chemical Activation
Directly attack infected cells
Other T cellsOther T cells Two other types of T cells exist:Two other types of T cells exist:
T suppressor cellsT suppressor cells De-activate immune response when the antigen is gone De-activate immune response when the antigen is gone
(opposite of helper cells)(opposite of helper cells)
Natural Killer CellsNatural Killer Cells Specifically kill tumour cells in a similar way to cytotoxic cells Specifically kill tumour cells in a similar way to cytotoxic cells
killing infected cellskilling infected cells
Both cell types are not well understoodBoth cell types are not well understood