Topic 5 - Specific Defenses Flashcards
When our body learns not to recognize self-antigens
Immunological tolerance
The recognition of epitopes is on a ____ level and involves receptors on on what?
Molecular level
B lymphocytes
T helper cells
T cytotoxic cells
What do B and T lymphocytes do within the primary lymphoid tissue?
- Learn to recognize non-self and response (alloreactive)
- Recognize self and not respond (not autoreactive)
**Cells that fail to do this are eliminated, maturation process takes a few weeks
What happens in the secondary lymphoid tissue?
It is the lymph nodes, lymph nodules, MALT, and spleen
- Where B and Ty lymphocytes first meet the epitope of the antigen via the antigen presenting cell
What are the surface receptors like on B lymphocytes?
- Thousands of the SAME surface receptors
- Covalently bind to one or a few closely related epitopes
B cell receptors are what?
Membrane bound forms of antibodies (which means that they have antibodies that are the non secreting form)
Describe the T cell receptors on lymphocyts
They are membrane bound protein receptors, but not antibody
Similarities between T and B lymphocyte receptors
They are both membrane bound but not both of them secrete antibodies
How are T, B, and NK cells differentiated?
Not morphologically, but they are differentiated based on their surface antigens
Characteristics of MHC Class I antigens
- Multiple
- Identical self angtigens
- Found of all nucleated cells
- Unique to the individual
- Major self marker
Characteristics of MHC class II antigen
- Multiple
- Identical self antigens
- Found only on B lymphocytes, macrophages, and dendritic cells!!!
What do MHC class II antigens play a dominant role in?
Antibody-mediated immunity
