Immunology Introduction Flashcards
What is the purpose of bone marrow and how is it involved in the immune system?
It is the site of hematopoiesis as well as the site for B-cell maturation
What is the purpose of the thymus?
It is involved in maturation and selection of T-cells
What is the purpose of the spleen?
It is a major site of immune responses to pathogens and other foreign substances in the blood.
How is the spleen divided?
It is divided into white pulp and red pulp. White pulp contains lymphocytes (T-cells near arterioles in the periateriolor shear; B cells are more peripheral). Red pulp is involved in RBC breakdown
What is the purpose of the lymphatic system?
1) Collect/drain excess fluid from surrounding tissue and return it to the vascular system 2) Absorb fat from the villi of the small intestine 3) Be a conduit for immune cells to and through the nodes back into circulation
What is lymph composed of?
White blood cells and plasma, but no RBCs
How is lymph pumped through the body?
Flow by skeletal muscle contraction, arterial pulsation, unidirectional valves, smooth muscle in walls of larger vessels
How is the drainage system divided in the lymphatic system?
2 separate drainage systems: 1) Lymph from upper right areas (right side of head, heart, and lungs) drain into the right lymphatic duct 2) The rest of the body drains into the thoracic duct, which then drains into the left subclavian vein
What is lymphedema?
Interstitial collection of lymph due to disruption of lymphatic flow
What is primary lymphedema?
Lymphedema associated with genetic or inherited conditions; can present at any age
What is secondary lymphedema?
Lymphedema due to underlying disease or a consequence of treatment. (etiology can be due to obstruction of lymphatic vessels or notes (compression by a tumor) or infiltration of vessels by tumor cells). Most common is BrCa
What is filariasis?
Most common cause of secondary lymphedema. Caused by the nematode Wuchereria bancrofti
How is filariasis treated?
Diethylcarbamazine citrate
What are some other diseases of the lymphatic system?
1) Lymphangitis 2) Chylothorax 3) Lymphadenopathy 4) Lymphadenitis 5) Lymphoma
What are the antigen presenting cells?
Dendritic cells, macrophages, B-cells
