Immunology Immunity Is the bodys ability to recognize

Immunology

Immunity � Is the body’s ability to recognize infectious disease causing organisms like bacteria and viruses, and protect the body from these organisms

Immunology � Study of the system that fights infectious diseases

Smallpox � Used to be one of the worldwide scourges � But because of immunization, smallpox no longer exists in the world

Before 1979 � Smallpox killed 80% of the children who contracted the virus, and about half the adults

Smallpox � Since 1900, it is estimated that smallpox was responsible for 500 million deaths � In 1967, the World Health Organization estimated that 15 million people contracted the disease and that two million people died in that year � After successful vaccination campaign, eradication of smallpox was declared in December, 1979.

AIDS/HIV � The hunt is on for a vaccine for HIV and AIDS � Many millions will die from AIDS before then

How do immunizations work? � Lock and key model

Antibodies are made by lymphocytes

� Fab binds to antigen � Fc binds to immune component

� Antibodies � Antigen bind to specific antigen – it can be any part of something, part of a bacteria, part of a virus that stimulates the immune system

Please do not confuse: � Antigen (Ag) – any protein or structure that can stimulate an immune reaction � Antibody (Ab) – Y shaped proteins that bind to antigens to mark them for phagocytosis. B lymphocytes make Antibodies

Antibody binds to antigen picture

� Antibodies can be free in the blood. � Antigen/Antibody complexes can signal digestion by macrophage � Antigen Antibody complex picture

� Antibodies can be attached to lymphocytes Ag/Ab complexes can signal the lymphocyte to reproduce making more of the same antibody � Antigen Antibody complex picture

Immunization � Now the body has a huge increase in the number of “receptors” that can activate the immune system in case of exposure to specific bacteria or viruses � Antibody picture

Immunization � So the next time the body is exposed to the specific bacteria or virus… � There already lots of antibodies to attack it

Immunity � Immunity prevents infection by the increased ability for Ab to signal the destruction of the infectious organism

Serum � SERUM is the liquid base of Blood � It is mostly salt water

SERUM � Contains small proteins called ANTIBODIES and COMPLEMENT � Again antibodies are made by lymphocytes � Complements are designed to attach to viruses and bacteria for phagocytosis

SERUM � ANTIBODIES and COMPLEMENT attach to foreign substances such as bacteria to help the IMMUNE SYSTEM fight these substances.

SERUM � Antibodies (Ab) are made by LYMPHOCYTES, a type of WHITE BLOOD CELL (WBC) � Complement are proteins made by the LIVER � Antibodies are very specific for antigens � Complements are not specific for antigens

Plasma = Serum + Clotting Factors � Clotting factors are proteins made by the LIVER � Clotting factors make your blood clot � - if you have no clotting factors, you would not stop bleeding from a tiny cut.