Immunity recognition Flashcards
How does the innate immune cells “recognise” non-self?
Innate = broad approach
PAMPs (Pathogen associated molecular patterns) - recognising motifs:
-foreign nucleic acid
-Virus double/single stranded RNA
-protein flagella (bacteria flagellate)
TLR (Toll-like receptors) multiple diff receptors/cell, many cells able to respond (FAST)
How does the adaptive immune cells “recognise” non self?
RAG (recombination activating gene): cells ability to rearrange its DNA to create a unique, combining small gene sections of pathogenic DNA into it’s own.
Each cell is genetically unique to a pathogen - multiple receptors per cell.
Cells need to be summoned by innate cells.
What different immune strategies do vertebrates use compared to invertebrates?
Invertebrates –> innate only
Simpler organisms.
Vertebrates (more complex systems) –> innate & adaptive (RAG)
Energetically expensive, risky, need more E stores. Cells take time to mature (longer lifespan needed)
How does the adaptive immune system interact with the innate immune system?
While adaptive system is very effective, it requires resources, too E expensive to maintain.
Thus, innate cells respond at first assessing the situation, then activate/summon specific adaptive cells (B & T cells) to eliminate foreign cells.
What are MHC molecules and what role do they play in the immune system?
MHC molecules (major histocompatibility complex) binds to specific antigens, presenting them to T-cells.
So that the T-cell can recognise there are foreign cells and direct the immune response against a specific pathogen and eliminate it.
How does the adaptive immune system use genetic diversity to enhance the immunity of the population?
Each individual has a unique set of lymphocytes (adaptive immune cells).
The olfactory genes are embedded in the genome where the MHC genes are. This results in mates preferring mates with different MHC combinations based on their smell.
Greater genetic diversity in offspring potentially gives them a survival advantage.
How are the innate and adaptive systems linked?
Antigen presentation - innate system (dendritic cells) present antigens to adaptive cells (T-cells)
Cytokine signaling (Innate cells release cytokines to activate and guide adaptive immune responses)
What are the innate immune cell groups?
Phagocytes: engulfing
Granulocytes: release of granules
Antigen presenting cells: phagocytosis & presentation of antigen to t-cell
Innate lymphocytes: natural killer cells
What are the adaptive immune cells?
B-cells (recognise antigens, release antibodies)
Cytotoxic cells (kills abnormal cells)
Helper T-cell (activates cytotoxic T-cells, communicates with other cells to ensure a co-ordinated attack)
