my husband is awesome Flashcards
Immune system physical barriers
Skin, Epithelial surfaces, Cilia
Immune system chemical barriers
Acids, Mucous, Lisozymes
Immunity is the body’s…….
Protective reactions to foreign invaders. Provides protection against INFECTIOUS DISEASE and supports HEALING. Malfunctions may result in immunity to self substances…“AUTOIMMUNITY”
Immunity is mediated by the collective coordinated response of….
Immune cells and the molecules they produce.
Innate immunity
“Native” immunity…nonspecific, quick (minutes to hours). Includes epithelium, secreted products, phagocytes, NK cells, plasma proteins, some cytokines
Adaptive immunity
Occurs on exposure to certain antigens (days to weeks). Includes lymphocytes, their secreted proteins (antibodies, cytokines), “antigen-presenting cells” (macrophages)
Adaptive immunity is divided into….
“Humoral” and “Cellular” components. Provides “memory” of prior exposures.
The immune system has the ability to distinguish…
“self” from “non-self”
Antigen
FOREIGN “non self” substance that provokes an immune reaction.
Autoantigens
Self-Molecules that inappropriately provoke an immune reaction
Allergens
Antigens that provoke HYPERSENSITIVITY RESPONSES (allergic response)
Most antigen are… (hint, molecular weight)
LARGE PROTEINS with molecular weight of 10,000 or higher. Insulin <6,000 daltons so doesn’t cause response
Epitope
Small part of an antigen that INTERACTS WITH A SPECIFIC ANTIBODY or immune cell ANTIGEN RECEPTOR
Any antigenic protein may have
SEVERAL EPITOPES
Each epitope is
RECOGNIZED BY A DIFFERENT, SPECIFIC ANTIBODY or immune cell ANTIGEN RECEPTOR
Primary lymphoid tissue
Bone marrow (red) and Thymus
Secondary lymphoid tissue
Lymph nodes, lymph nodules and lymph vessels; Spleen
Leukocytes
White blood cells, WBC
Primary lymphoid tissue are organs where
Immune and other blood cells are made and matured.
Red bone marrow…
Provides pluripotent stem cells; Give rise to all of the different types of blood cells.
Thymus
Gland above the heart in the thorax. Site of T lymphocyte maturation, develop “self tolerance” prior to entering into the blood circulation.
Thymus is located…
in the thorax between the thyroid and the heart. Thymic tissue hypertrophies during childhood but after puberty it atrophies and is replaced by fat, continues to function to some extent throughout life.
Cells contained within the thymus
T lymphocytes - present at various states of maturity
Epithelial cells - endocrine gland, produce hormones that direct T cell matruation (thymulin, others)
Macrophages - phagocytes
Secondary lymphoid tissue serves to…
promote efficient interactions between antigens and immune cells and a controlled environment for the development of immune responses.
Secondary lymphoid tissues include:
Lymph nodes (along lymphatic vessels) Lymph nodules (on mucosal surfaces) Includes tonsils and adenoids, Peyers patches (on intestine), others
Lymphokinetic motion and pressure gradient (high to low pressure)
Blood capilaries —> Interstitial Fluid —>Lymph capillaries —> Lymph veins —>Lymph ducts —>Large circ veins
The lymphatic vasculature…
Drains tissue fluid, cells and antigens from most tissues, through lymph nodes and back into blood via thoracic duct.
Lymph node locations?
Axillary, Brachial, Deep cervical, superficial cervical, inguinal, lumbar, mediastinal, mesenteric, popliteal, pancreatic, renal, sacral, sciatic, facial
Axillary - Armpit
Brachial - Biceps beneath pectorals
Deep cervical - behind salivary gland
Superficial cervical - in front of salivary gland
Inguinal - adherent to skin of groin
Lumbar - behind split of abdominal aorta
Mediastinal - thymic region
Mesenteric - Mesentery of small intestine and pancreas
Popliteal - bhind the knee
Pancreatic - between pancreas and stomach
Renal - between aorta and kidneys
Sacral - In front of the split of the abdominal aorta
Sciatic - Below sciatic nerve
Facial - Draining the face
What do lymph nodes do?
Lymph nodes “filter” the lymph. Provide a space for active immune cells to interact with antigen carried from interstitial fluid. Lymph nodes enlarge during an immune response (due to lyphocyte proliferation).
Lymph nodules are associated with…
Mucosal surfaces. Gastrointestinal tract, respiratory tract, breast, urogenital tract
Examples of GI lymph nodules:
Tonsils, adenoids, Peyer’s patches on intestinal tract, Lymphoid aggregates in the appendix, small diffuse lymphoid aggregates in the esophagus, on other mucosal surfaces
Lymph nodules are characterized by…
Overlying epithelial covering with specialized phagocytic epithelial cells that TRANSFER ANTIGEN INTO THE LYMPHOID TISSUE. Immune cells interact with antigen and STIMULATE IMMUNE RESPONSE. Nodules ENLARGE just like nodes during immune response. Results in SECRETORY IgA PRODUCTION, prevents microbial binding to mucosal surfaces.
Spleen
Located in the LEFT UPPER QUADRANT of the abdomen. Functions as a FILTER FOR ANTIGENS IN THE BLOOD, a site for IMMUNE REACTIONS, and as a STORAGE ORGAN FOR ERYTHROCYTES.
What surrounds the spleen
TOUGH CONNECTIVE TISSUE CAPSULE surrounds the spleen and short septa extend inwards. Rupture of capsule results in “ruptured spleen”, significant abdominal bleeding.