Immunosuppresion Flashcards
What are the 9 organs of the immune system?
- Adenoid
- Tonsil
- Thymus
- Lymphatic vessels
- Lymph nodes
- Spleen
- Peyer’s patches in small intestine
- Appendix
- Bone marrow
What is the goal of an immune response?
To recognize and remove invading microorganisms and tumor cells
What is the goal of immunosuppression?
To minimize the impage of exagggerated or inappropriate immune responses
Describe the following characteristics of the innate immune system:
- Onset
- Mechanism of action
- Cell types involved
- Soluble factors
- Onset: immediate
- Mechanism of action: Pattern recognition receptors recognize common molecules on microbes and viruses
- Cell types involved: Macrophages, neutrophils, mast cells, naturall killer cells, NK T cells, innate lymphoid cells
- Soluble factors: Complement, Type I interferon, select cytokines and chemokines
Describe the following characteristics of the acquired immune system:
Onset
Mechanism of action
Cell types involved
Soluble factors
- Onset: days to weeks
- Mechanism: Antigen-specific receptors (T-cell receptor, B-cell receptor)
- Cell types: Dendritic cells, T cells, B cells
- Soluble factors: Select cytokines and chemokines
What are the steps involved in Cell mediated Acquired immunity?
- Antigen presenting cell binds Th1 and pCTL, converting pCTL into an effector CTL (with TH1 Interleuken 2)
- Effector CTL binds tumor cell and causes cell lysis
What are the processes involved in humoral acquired immunity?
- APC binds Th2 cell, turning it into activated T cell
OR
- Memory B cell binds Th2 cell, turning it into activated T cell
- Activated T cell binds B cell, becoming activated B cell
- Activated B cell becomes Memory B cell (For future infections)
- Activated B cell becomes Plasma cell (proliferation of antibodies)
Name four reasons to use immunosuppresive agents
- Autoimmune disease
- Isoimmune disease (eg Rh hemolytic disease of the newborn)
- Organ transplantation
- Prevention off cell proliferation
What is Rhesus hemolytic disease?
Isoimmune disease
- During birth, Rh+ fetal erythrocytes leak into maternal blood after embryonic chorion ruptures.
- Maternal B cells are activated by Rh antigen and produce large amounts of anti-Rh antibodies
- Rh antibody titer is elevated in mother’s blood from first exposure
- Rh antibodies are smol enough to cross embryonic chorion and attack fetal erythrocytes
Mother is fine (physically 😢) and fetus dies
What are 4 types of organ transplant?
- Isograft (identical twins)
- Autograft (within an individual)
- Allograft (non identical individuals) *best HLA match
- Xenograft (between species)
What are HLA antigens and what can they help determine?
Human leukocyte antigens
Major determinant of tissue compatibilty
Ligand/receptor pairings on APCs/Tcells
Name the three targets for immunosuppresive drugs in order of selectivity (lowest to highest)
- Cell proliferation (lowest)
- T cell function
- Antibody approaches: antigen recognition (highest)
Name two types of drugs for Cell proliferation and name an example of each
- Glucocorticoids
- Prednisone
- Cytootoxic drugs
- Cyclophosphamide
- Azathioprine
- mycophenolate mofetil
- methotrexate
What is the effect of prednisone?
Glucocorticoid receptor agognist
How do glucocorticoids function?
- Decrease transcription of inflammatory genes
- Increase expression of anti-inflammatory genes
- Decrease production of prostaglandinsm cytokines and interleukins (IL-1,IL-2)
- Decrease proliferation and migration of lymphocytes and macrophages