Active Immunity This occurs when the body creates the antibodies for itself and creates a new population of T cells and B memory cells Immunity can last a lifetime – B memory cells and T memory cells are created Two types – Natural and Induced/Artificial

Natural Active Immunity The body makes the antibodies Occurs when the person comes into contact with the pathogen cold, flu, chicken pox Immunity can last a life- time B memory cells produced

Induced/Artificial Active immunity The body make the antibodies Occurs when a person is vaccinated eg polio, meningococcal Immunity can last a lifetime B memory cells produced

Injections – Vaccination Dead organism Small dose of live organism (eg. Polio) Attenuated organism – remove disease causing capacity Toxin – treated venom Designer protein vaccinations (eg. Hep B and meningococcal)

Why do we still get sick? Bacteria have a capsule that can hide antigens from the immune system Viruses can mutate from year to year changing their protein coat so the B memory cells do not recognise the virus

Active Immunity Number of antibodies Time Primary response Secondary response

Passive Immunity The body does not make the antibodies Lasts only a short amount of time as no B memory cells are created Immediate protection Two types natural and induced/artificial

Induced/Artificial Passive Immunity Antivenom given after a snake bite (rabbits antibody factories) Injections of Immunoglobins (antibodies) No B or T memory cells created Last 2-3 weeks

Natural Passive Immunity Antibodies can move across the placenta to a baby Colostrum thick milk produced by a mother for a few days after giving birth

Passive Immunity Time Level of antibody

Problems with the immune system Things that can go wrong

Rhesus Factor Markers found on red blood cell People are either positive (have proteins on their surface) or negative( have no proteins on their surface Rhesus negativeRhesus Positive

Mum Rh -ve

Blood types Blood type A Blood type B Blood type AB Blood type O

Blood transfusions Blood type A has Antibodies to – Blood type B has Antibodies to – Blood type AB has Antibodies to – Blood type O has Antibodies to -

Blood transfusions Blood type A can Donate to Blood type B can Donate to Blood type AB can Donate to Blood type O can Donate to

Blood type transfusions Blood type A can accept from – Blood type B can accept from – Blood type AB can accept from – Blood type O can accept from -

Transplants Rejection of tissue Only identical twins have the same markers T helper cell identifies tissue Cyclosporin suppresses T cell highly toxic to kidneys Need to match markers closely

Auto immune diseases Arthritis – joint cartilage Multiple sclerosis – myelin layers around axon degenerates

Allergies Mast cells and Basophil cells Mast cells located around blood vessels, connective tissue, lining of gut and lungs Both contain large numbers of histamine – contraction of smooth muscle