4/6/99

Microbiology II

 

Host Defense

·        Cells of immune system:  lymphocytes (T, B, blast, plasma)

·        Structure of antibodies—antigens/immunogens

·        Antigen—is a substance which stimulates production of antibodies  to a foreign substance—has a specific effect to produce unique antibodies to specific antigen

·        Are most free proteins

·        Greater the incompatibility of the proteins from an individual to the host system the greater is the antigenicity

·        Nucleoproteins, glycoprotein, lipoproteins—associated proteins

·        All of these can be antigenic

·        Molecular wt of a molecule of 10,000D can be antigenic

·        ADJUVANT

·        Such substance which are not antigenic, but enhance the antigenicity of other substances

·        Endotoxin—Gram (-)

·        Emulsions—oil in water

·        Aluminum hydroxide—enhances antigenicity of other agents

·        All of these can be added into vaccines

·        Haptens—synthetic chemicals; by themselves are not antigenic in nature, but when joined w/an antigenic protein become antigenic ex:  2,4 dinitrophenyl

 

Occult antigens—not recognized as an antigen under normal circumstances, in disease situations or under injury it is recognized as an antigen—autoimmune diseases have them associated w/them