Immunology: Antigen (Part - 2)

Описание: Microstudy/Dr Ahmed Talaat
قناة متخصصه لشرح مادة الميكروبيولوجي والمناعة لجميع طلبة الكليات العملية

Immunology: Antigen (Part - 1)
   • Immunology: Antigens (Part-1)  

Factors that Influence Immunogenicity:
1- Foreignness:
For a substance to be immunogenic it must be foreign to the animal in which it is introduced. The immune system of an individual can normally distinguish between body components, i.e. "self and foreign substances "non-self.
2- Molecular size: Small molecules such as amino acids or monosaccharides are usually not immunogenic.
As a rule, molecules with a molecular weight of less than 5000-10,000, (5-10 kDa)
are non-immunogenic
3- Chemical nature: The most potent immunogens are proteins. Some polysaccharides
of high molecular weight. More complex proteins are more immunogenic i.e. globular proteins are more immunogenic than fibrillar proteins.
4- Degradability: For a substance to be immunogenic it has to be susceptible to partial enzymatic degradation that occurs during antigen processing by presenting cells such as macrophages.

Other factors:
A- Dosage.
B- Route of administration.
C- Adjuvants.
Types of Antigens
1 - Bacterial antigens
2- Viral antigens
3- Superantigens