Immune Response Flashcards
Immunology
the physiological mechanisms that humans and animals use to defend their bodies
Immunity
capacity to resist a particular disease
Immune response
the general reaction of the body to substances that are foreign
Innate Immunity
primary defense, no immunological memory. *physical barriers, phagocytosis, lysozyme, TLR, and inflammasomes *
-rapid response
Adaptive Immunity
secondary defense, immunological memory required
-slow response
Cells of the immune system
white blood cells or leukocytes (hematopoietic cells)
Primary lymphoid organs
Thymus and bone marrow
Secondary lymphoid organs
spleen, tonsils, lymph nodes, urogenital lymphoid tissue
Lymph node
mature B and T cells enter then are activated by the pathogen
Macrophages
cells involved in the detection, phagocytosis, and destruction of bacteria and other harmful organisms. Secretion of cytokines and chemokines that induce cell signaling
Complement
certain molecules or fragments activate cells of both types of immunity
Complement cascade
-part of innate immune system
Membrane attack: rupturing the cell wall of bacteria
Phagocytosis: by opsonizing antigens
Inflammation: attracting macrophages
Toll-like receptors TLR
expressed on sentinel cells such as leucocytes including dendritic cells that recognize structurally conserved molecules distinguished between self and nonseld cells
Lymphocytes
white blood cells that increase the power and focus of the immune response
Effector lymphocytes
divide for proliferation (CLONAL SELECTION) and differentiation (CLONAL EXPANSION)
Antigen Presentation
APC process antigens and present them to T cells, T cells recognize the complexes using receptors TCRs
Professional APC
macrophages, B cells, and dendritic cells present antigens to T cells express MHC II
Non-professional APC
express MHC I molecules
TH1
- Reinforces an early response
- promotes an inflammatory response
- mediates type IV hypersensitivity
TH2
- activates later, systemic responses
- Promotes humoral and allergic responses
- limits the inflammatory response
TH17
- activates epithelium and neutrophils
- promotes inflammation and autoimmune responses
- inhibited by TH1 and TH2 responses
Treg Effects
- suppresses new responses
- regulates autoimmune responses
Edward Jenner
The father of immunology
Active immunization
stimulation with a specific antigen to induce an immune response
