Unit 2: Adaptive Immunity Flashcards
B Lymphocytes
-Humoral immunity
-Secretion of ANTIBODIES by plasma cells
-Defend against: bacteria , toxins, viruses in body fluids
T-Lymphocyte
-Cell-mediated immunity
-Production of cytokines by helper T cells
- Lysis of cells by cytotoxic T cells
Define Antigen
Antibody generators confer specificity
Define Epitope
Recognition sites for B or T cells
Define antigen receptors
Recognize certain antigens only
B Cells
Membrane antibodies or B cell receptors ( BCR’s)
T Cells
T cell receptors (TCR)
Specificity
B & T cells have receptors (BCRS & TCRS) that can recognize and bind to specific antigens
Diversity
B & T - lymphocytes have the ability to recognize billions of different epitopes
Memory
First exposure to antigens selects/expands clones of B&T cells effector cell (deal w/ pathogen) and memory cells (long lived) subsequent exposure to antigen is faster / greater magnitude (memory cells)
Self-Tolerance
During their development B & T cells that recognize self antigen are deleted
Autoimmune disease= failure of self tolerance
3 types of T cells
1) helper T cells
2) cytotoxic T Cells
3) Regulatory T cells
Helper T cells
Secrete cytokinesis that enhance activity of b cells and other t cells
Cytotoxic T cells
Kill virus - infected cells and abnormal cells
Regulatory T cells
secrete cytokines that suppress activity of B cells and other T cells
Which T cell expresses CD4?
Helper T Cells
Which T cell expresses CD8?
Cytotoxic T cells
Which T cell binds to MHC class ll?
Helper T cells
Which T cell binds to MHC class 1?
Cytotoxic T cells
Which T cell kills cells infected with/ viruses and tumor cells?
Cytotoxic T cells
What are perforins? What cell are they associated with?
Form pore in membrane of infected cell.
-cytotoxic cell
What are cytokines? What T cell are they associated with?
Associated with Helper T cells
-stimulate and regulate immune response
Effector Cells
-combat antigen that stimulated production
-short lived
Memory cells
-long lived
-antigen specific
Primary Immune Response
-first exposure to antigen
-10-17 days to occur
-symptoms of illness occur during these days
Secondary Immune Response
-subsequent exposures to antigen
- 2-7 days to occur
- greater magnitude response and more prolonged
- occurs due to presence or memory cells
