Chapter 17. Immunology and Immunizations part I Flashcards
Organs concerned with the growth, dev. and deployment of lymphocytes, white blood cells (WBC) that are key operatives of the immune system.
Lymphoid organs
Lymph nodes are small, bean-shaped structures that are laced throughout the body along the lymphatic routes. Contain specialized compartments where immune cells congregate, and where they can encounter antigens.
White blood cells (WBC) or leukocytes are two types:
- Granulocytes- polymorphonuclear leukocytes.
- Monocytes- mononuclear leukocytes without granules in their cytoplasm
Normal range of white blood cells are 4000 to 11000/cmm. Give each cytes WBC % content of lymph, neutro and mono.
- Lymphocytes. About 30% of white blood cells are lymphocytes.
- Neutrophils: About 60% of white blood cells are neutrophil.
- Monocytes: About 8% of white blood cells are monocytes
The polymorphonuclear leukocytes define each, (granulocytes) Neutrophils, Eosinophils and Basophils.
Neutrophil- most abundant WBC. ↑ in number of neutrophil indicates bacterial infection
Eosinophils- defending against parasitic worms. ↑ in eosinophils indicates parasite infection and allergies
Basophils- Smallest circulating gran. Discharge the contents of their granules, releasing mediators such as H, 5HT, PG, and Lk
B CELLS (B lymph.) mature into plasma cell that secrete antibodies (Ig), the proteins that recog and att to foreign subs, antigens. Each type of B cell makes 1 sp. a.body, wc recog 1 sp antigen. Give examples of B cells and their corres. membrane antibodies.
VIRGIN B CELLS: never respond to an antigen since they release into the circulation from bone marrow =Ig M & D
MEMORY B CELLS: are derived from cell division form another B cell that has responded to an antigen= Ig A, Ig E, Ig G
T cells— regulate the complex workings of the immune system, while others are cytotoxic and directly contact infected cells and destroy them. 2 types and define.
1) “helper/inducer” T cells- activate many immune cells, B and T. Another subset of regulatory T cells acts to turn off or suppress immune cells.
2) Cytotoxic T cells help rid the body of cells infected by viruses and by cancer, also for the rejection of tissue and organ grafts.
T cell do not enter the circulation directly from bone marrow. But first enter this gland, most mature here then die. 2 types of T cells and define.
THYMUS GLAND
VIRGIN T CELLS: Release from thymus to circulation are virgin T cells.
MEMORY T CELLS: Originate through cell division and responses of other T cells.
Normal CD4 count.
Normal CD4 count is from 500 to 1,500 cell per cubic millimeter of blood.
The helper T cells (TH cells)
These cells produce lymphokines (cytokines) are small proteins that act on other cells in autocrine, paracrine, and endocrine manner. Give the 2 types and define.
TH1- Activate other cells, inhibit antibody production by inhibiting the formation of TH2
TH2- Activate B cells to divide and produce antibody.
2 types of Lymph are killer cells that can inc RBC and reduce the need for RBC transfusions in patients receiving chemo
This can reduce the need for platelet transfusions in patients receiving chemotherapy.
At least two types of lymphocytes are killer cells; cytotoxic T cells and natural killer cells
-Oprelvekin
These are white blood cells that can swallow and digest microscopic organisms and particles in a process known as______. Also known as “big eaters.”
MONOCYTES— Phagocytosis
Monocytes can also travel into tissue and become MACROPHAGES
Secreted during what response? Give serum Ig and t1/2z It is secreted across mucosal surfaces into gastrointestinal, respiratory, lachrymal, mammary, and genitourinary secretions. Where this protects mucosa from colonization of pathogen (Bacteria) and other microorganisms.
Ig A~10%
secreted during memory response
5 days
This is secreted at the end of primary immune response and during memory responses. It diffuses from blood into other extra cellular fluids, particularly in inflamed vasculatures, and it crosses the placenta to enter the fetal circulation.
Ig G ~70% -predominant Ig
25-35 days
This binds to what Ig located on the cell surface of blood basophils and on connective tissue mast cells to trigger the secretion of inflammatory mediators from these cells in the presence of specific antigen. Mediates allergic reactions (asthma).
Ig E ~1%
2-3 days
When this bound mast cells, the serum t1/2 is months. It does not leave the blood in significant amount because of it PENTAMERIC STRUCTURE (molecular size 900,000 daltons).
Ig M What Ig is the -least common, -found in exocrine gland -only Ig that can cross the placenta - 1st Ig aft immuniz. but later gives way for another Ig
This accounts for ~ 20%. Serum halflife 9 to 11 days.
IgM is the most potent activator of all immunoglobulins, resp. for blood type
Subclass: IgM1 and IgM2
-Ig D
-Ig M
