Immunology in Health and Disease Flashcards
What are the five cellular phases involved in the progression to cancer?
Normal, hyper plastic, dysplastic, neoplastic and then metastatic
What are the innate defences?
Surface barriers - skin and mucous membranes
Internal defences - phagocytes, fever, NK cells, antimicrobial proteins and inflammation
What are the adaptive defences?
Humoral immunity - B cells
Cellular immunity - T cells
What are lymphocytes?
These are a type of white blood cell that are found in the blood and lymphoid organs and these include B cells, T cells and natural killer (NK) cells
What are phagocytes?
White blood cells that can swallow and digest microscopic organisms and particles via phagocytosis
What are monocytes?
These cells circulate in the blood and then differentiate in tissues into macrophages and dendritic cells, macrophages arelocated in tissues throughout the body.
What are dendritic cells?
These are specialised cells that present antigens to the cells of the immune system
How does the innate immune system recognise foreign cells/antigens?
Innate immune system is involved in the initial screening of self and non-self antigens using pattern recognition receptors (PRRs) that recognise pathogen-associated molecular patterns (PAMPs) such as bacterial cell wall, unmethylated CpG DNA
What is the necessary first step for the activation for adaptive immunity?
Activation of specialised antigen presenting cells
What are natural killer cells?
• kills any cell that doesn’t have a MHC class I receptor (as it can’t stimulate a negative/inhibitory signal on the NK cells) and this leads to release of granules inducing apoptosis in the target cell
What form of immunity are natural killer cells a part of?
Innate immune system
How do natural killer cells work?
• kills any cell that doesn’t have a MHC class I receptor (as it can’t stimulate a negative/inhibitory signal on the NK cells) and this leads to release of granules inducing apoptosis in the target cell
How does the immune system kill cancer cells?
Cytotoxic (CD8+) T cells and helper T cells;
Cytotoxic - attach to MHC class I peptide complex and perforates membrane by enzymes and induces apoptosis
Helper (CD4+) T cells attach to class II MHC peptide complex which leads to cytokine secretion
What are the two forms of differentiated CD4+/helper T cells?
Th1 and Th2
How do Th1 and Th2 cells differ?
Th1 cells cause a cytotoxic response, Th2 cells cause an antibody response
