Exam 1 Flashcards
what is a pathogen?
any disease causing organism
what is an antibody?
a soluble factor produced by B cells (IgG, IgM)
what is an antigen?
molecules from a pathogen or foreign organism that provoke a specific immune response; but are present on all cells and can be used to identify different cell types
what is an epitope
a small portion of an antigen recognized by an antibody or T cell
where are most immune cells?
diffuse across the body, in the lymphatics, spleen, and appendix
how does the bone marrow contribute to the immune system?
produces blood stem cells (B cells mature here)
how does the thymus contribute to the immune system?
T-cells mature here
how does the spleen contribute to the immune system?
it removes red blood cells, removes infections, and activates lymphocytes
how do lymph nodes contribute to the immune system?
“barracks” of immune system
how do lymphatic vessels contribute to the immune system?
has fluid leaked from blood
how do brain lymphatics contribute to the immune system?
hide in channels of the skull (think its what goes wrong in neurodegenerative diseases)
what are neutrophils?
the first line of inflammatory defense in the innate immune system, respond immediately
macrophages
are important for the resolution of inflammation in the innate immune system and clean up viruses, dead tissue, etc. they sit in the edges of the lymphatic system, living as monocytes before being developed
professional antigen prensenting cells
dendritic cells, macrophages, B cells
cytokines
most are inflammatory, but IL-10 is anti-inflammatory !!
secreted by almost all cells to call more cells to battle
B lymphocytes
make antibodies, make up the humoral immunity
T lymphocytes
T-helper, T-killer, make up cellular immunity
the role of B lymphocyte in the immune response
secretes antibodies to block infection
what is the role of helper T lymphocytes?
they activate macrophages to kill phagocytosed microbes
what is the role of cytotoxic T lymphocytes?
they kill infected cells
the process of B cell activation
- receptor recognizes an antigen
- it then displays class II MHC and a helper T cell binds to it, further activating the B cell
- the helper T cell releases cytokines to call other lymphatic cells there
- the activated B cell becomes a plasma cell and releases millions of antibodies
what occurs in anergy?
the B cell doesn’t experience signal 2 (when the T cell further activates it) so it doesn’t mount a full auto-immune reaction
what are antibodies?
proteins that recognize specific antigens and are released by B cells
T cells
recognize foreign antigens on the surface of cells, organisms, tissues, they regulate proliferation of other immune cells (B cells, macrophages, neutrophils)
