Introduction to Immunology Flashcards
primary roles the immune system plays in our body
-protects us from infection through various lines of defense
-distinguishes harmful infections from harmless organisms that live in our bodies
difference between innate and acquired/adaptive immunity
innate:
nonspecific, fast, determines self vs non-self, limited in impact with challenging pathogens
first line of defense, presents foreign antigens to the adaptive response
adaptive:
specific, takes days to develop, achieves memory and tolerance, can have self/non-self identification challenges, develops specific effector responses against a specific pathogen
role of the immune system in defense
prevents foreign materials from setting up shop in the body
role of the immune system in surveillance
identifies cells that are denatured/unhealthy and eliminate
role of the immune system in homeostasis
removes dead cells and debris as cell cycle occurs
properties of the immune system that makes it highly functional
redundant: multiple levels of protection
comprehensive: complete coverage of the entire body
tolerant: discriminate healthy from sick; self from non-self
diverse and agile: many pathogen detection routes and responses
communication: between immune and non-immune cells
memory: against infectious agents for fast subsequent response
self-limiting: restore homeostasis after the challenge is removed
what is an antigen
-the basis to the immune response
-antigen proteins provide a recognition site for foreign objects
how does the immune system discriminate self vs non-self
identifying self: a self marker (MHC) labels the body’s cells as friend are tolerated by the immune system
identifying non-self: an antigen is recognized as foreign and treats as a foe
what is the collaborative role between specific and non-specific responses
non-specific innate immunity provides rapid generalized protection and a template for specific immune responses
specific adaptive immunity learns from non-self exposure to provide a very efficient elimination and future protection
relationship between innate and adaptive immunity
development of specific memory allows the immune system to respond quickly with a second exposure
once the innate immune system recognizes the antigen, it adapts and learns and when exposed to the antigen another time the adaptive immune system works quicker and more efficiently
organs of the immune system
lymphatic system: returns liquid lymph back to circulation into the blood
lymph nodes: sample antigens and display to lymphocytes
spleen: performs a similar filtering function
thymus and bone marrow: educates leukocytes for self vs non-self (primary lymphoid tissues)
white blood cells
functional at identifying foreign substances in circulation or transported to sites of need
the hematopoietic system
mediators of immunity
two major lineages:
-myeloid - granulocytes (innate immunity) and RBCs
-lymphoid - lymphocytes (adaptive immunity)
cytokines and chemokines and their role in immunity
-essential for communication between leukocytes
-broad functions that depend on both the message and the recipient
-cytokines - signals can integrate to cause different outcomes
-chemokines - a subset of cytokines that promote cell migration
physical barriers to infection and their role
top layers of epithelium: cover the body
mucous membranes: separate environment and membranes and can trap pathogens
mucociliary clearance: mucous is continually generated and pushed out of the lungs (cliae)
commensal bacteria: coat mucous membranes and skin limiting the space available for bacteria
glands: flush exposed membranes and secretions contain anti-microbial peptides and digestive enzymes
stomach: has very low pH <3
