Question | Answer |
What activates the first component (C1) of the complement system? | IgM and IgG antibodies form antigen-antibody complexes that activate C1 |
How many proteins does the cascade reaction involve? | More than 20 proteins. Results in a number of active proteins, the results are not antigen specific. |
6 results of complement system | Lysis - direct lysis of the pathogen membrane/ pore formed Opsonization - coats the pathogen, allows phagocytosis by macrophages or neutrophils Chemotaxis - attracts neutrophils and macrophages to the area Agglutination - clumping of antigens together Virus Neutralisation - some viruses become non-virulent Inflammation - increase local reaction by stimulating the release of histamine |
Which antibody is involved in the anaphylactic system? Which cells does it attach to? | IgE Mast cells in tissues and Basophils in blood |
Outline the anaphylactic system | When an antigen reacts with exposed IgE on the mast cell, the cell enlarges, ruptures and releases histamine and other substances. Causes local vasodilation and inflammation Some people show an extreme systemic response as well from the basophils in the blood system. |
What is the effect of the release of histamine and other substances in the anaphylactic system? | When released in vast quantities, causes extreme vasodilation and capillary permeability. Severe constriction of the bronchioles may follow, with rapid loss of BP results in the anaphylactic shock. |
What % of the population shows an allergic disorder such as asthma, hay fever or food allergy? | 20% |
Why do some people become allergic and others don't? | Malfunction of the immune system. Persons with allergic tendency tend to produce antibodies against mild antigens (allergens). These don't elicit a response in normal individuals. |
Outline Allergic Rhinitis (Hay Fever). | Sensitization where the degraded allergen is presented to a T cell which in turn activates a B cell to produce IgE. IgE attaches to receptors on mast cells Mast cells are activated. Exposure to aerial pollen grains stimulates more IgE antibody (reagins) release from the sensitized plasma cells in the nasal mucosa. IgE - appropriate mast cell by C region; pollen combines with V region --> release of histamine, serotonin, other substances Dilation of capillaries --> oedema and inflammation --> sneezing/coughing/running nose If sensitized cells are in the respiratory tract, asthma may result |
Want to create your own Flashcards for free with GoConqr? Learn more.