Chapter 35 Immune System Flashcards
What are the anatomic components of the immune system?
Bone marrow - WBCs are produced here (including B and T lymphocytes) by stem cells
Lymphoid tissues - spleen (white pulp contains concentrations of lymphocytes,red pulp filters and destroys old and injured RBCs), lymph nodes (connected by lymph channels and capillaries) serveas centers for immune cell proliferation
Intestines
Appendix
Thymus
Tonsils
Bronchus associated lymphoid tissue
Peyers patches
What are the components of natural immunity?
Natural immunity - First line, protects host without remembering prior contact with infectious agent. Response if similar from one encounter to next regardless of number of times the invader is encountered. cytokines are produced as well as other effector molecules, these molecules either activate cells to destroy pathogens or to promote the development of the acquired immune response.
- Cells involved - moncytes, macrophages, dendrite cells, NK cells, basophils, eosinophils, granulocytes.
- can be immediate (within 4 hours) or delayed (between 4-96 hours)
Includes WBC action, physical and chemical barriers, inflammatory response, immune regulation.
Physical and chemical barriers of natural immunity?
-Physical and chemical barriers - Physical: intact skin, mucous membranes, cilia of respiratory tract (along with coughing and sneezing)… Chemical: mucus, acidic gastric secretions, enzymes in tears and saliva, substances in sweat and sebaceous secretions.
Inflammatory response of natural immunity?
- Inflammatory response - Response to tissue injury or invading organisms. Chemical mediators assist by minimizing blood loss, walling off invading organism, activating phagocytes, promoting formation of fibrous scar tissue and regeneration of injured tissue.
WBCs of natural immunity and action?
WBC action - Neutrophils (G, first responders, phagocytosis), basophils and eosinophils (G, allergic reactions and stress responses, phagocytosis), monocytes (AG, phagocytosis), lymphocytes (T and B cells, humoral and cell-mediated response, 60-70% lymphocytes in blood are T, 10-20% and B cells)
Describe immune regulation associated with natural immunity.
Balance and counterbalance:
If immune response fails to develop or sufficiently develop the host is considered immunocompromised or immunodeficient
If response is overly robust or misdirected, allergy, asthma, or autoimmune can result.many autoimmune disorders see self as not self.
ALL ABOUT BALANCE
Describe acquired immunity.
This usually results from prior exposure to an antigen through immunization or by contracting a disease. Weeks to months after exposure to disease or vaccine the body produces an immune response sufficient enough to defend against re-exposure.
this immunity recognizes specific antigens and takes time to develop.
Divided into two mechanisms: 1) cell mediated (T cell) and 2) effector mechanisms - B cell maturation and production of antibodies
What is the difference between active and passive acquired immunity?
Active acquired - developed by own persons body and lasts many years or lifetime.
Passive acquired immunity - temporary immunity transmitted from a source outside the body that has developed immunity through previous disease or immunization EXAMPLE: transfer of antibodies from mother to infant through breast feeding, or injections of immune globin
These both involve humoral and cellular immune responses
Describe the phagocytic response to invasion.
Involves granulocytes and macrophages that ingest invading agents and bodies own dying cells (ones that are necrotic or apoptyze)
Describe the humoral cellular response to invasion.
starts with B cells, that turn into plasma cells that produce antibodies that are specific proteins designed to attempt to disable invaders.
Sometimes B cells dont recognize antigens and the T cells and macrophages have to take a blueprint of the antigen to the nearest lymph node to tell B cells to differentiate to plasma cells to make antibodies.
Describe the cellular response to invasion.
T lymphocytes are primarily responsible, T cells mature in the thymus, despite the slight degeneration during puberty. No antibodies, attack cells directly. Antigen receptors on T cells allow this cellular reaction without assistance of macrophages. After recognition they go to lymph nodes to stimulate production of more T cells which then either stay in lymph node for memory or circulate in system until they either reach the tissues or die
T effector cells:
- T helper - CD4, destroy foreign antigen, activate on recognition of antigens, create cytokines which attract B cells, NK cells, CD8 cells, macrophages, ect…
- Cytotoxic T cell - CD8, destroy foreign antigen
T suppressor cells - control and suppress immune response by controlling B cell production
Memory T cells - stay in lymph node after response to retain memory of antigen
null-lymphocytes require antibodies to be attached to antigen, in which the cell combines to the attached antibody, known as antibody-dependent cell-mediated cytotoxicity, differentiated from helper T cells
NK cells are differentiated from helper T cells, these kill infected and stressed cells by secreting macrophage-activating cytokine.
What are some examples of cellular and humoral immune responses?
Chart 35-1 P. 973
Humoral (B cells): bacterial phagocytosis and lysis, anaphylaxis, allergic hay fever and asthma, immune complex disease, bacterial and some viral infections
Cellular (T cell): transplant rejection, delayed hypersensitivity (tuberculin reaction), graft vs. host disease, tumor surveillance and destruction, intracellular infections, viral fungal and parasitic infections
Age related changes in immunologic dysfunction?
READ P. 979!!!!!!
What are some medication classes that negatively effect the immune response?
What about blood and HIV?
Antibiotics (large doses)
Antithyroid drugs
NSAIDs (large doses) and salicylates
Adrenal corticosteroids
Antineoplastic agents (cytotoxic agents)
Antimetabolites
Anesthetics
READ CHART 35-5 on P. 982
Also ask about herbal agents and OTC medications!!
There is a very low risk to get HIV from blood transfusions with the testing and assessments that now take place before donation. However, abnormal immune function may occur after blood transfusion due to exposure of foreign antigens.
