Vaccines (lecture 1) Flashcards
10 Leading causes of death (Low-income countries)
- Lower respiratory infections (11.30%)
- Diarrhoea diseases (8.20%)
- HIV/AIDS (7.80%)
Ischaemic heart disease (6.10%) - Malaria (5.20%)
Stroke/cerebrovascular disease (4.90%) - TB (4.30%)
Prematurity low birth weight (3.20%)
Birth aphyxia and birth trauma (2.90%)
Neonatal infections (2.60%) - = communicable diseases
10 Leading causes of death (high income countries)
Ischaemic heart disease (12.80%) Stroke/cerebrovascular disease (10.80%) * Lower respiratory infections (6.10%) Chronic obstructive pulmonary disease (5.80%) * Diarrhoeal diseases (4.30%) * HIV/AIDS (3.10%) Trachea/bronchea/lung cancers (2.40%) * TB (2.40%) Diabetes mellitus (2.20%) Road traffic accidents (2.10%)
- = communicable disease
Solution to communicable diseases (infectious diseases)
Vaccines
- Useful
- Cost efficient
Give an overview to the immune system (4 types)
Organs
Complement
Phagocytes
Lymphocytes
Organs: Bone marrow, Thymus, Spleen, lymph nodes
Complement: Plasma proteins that interact with pathogens marking them for destruction by phagocytes
Phagocytes: Granulocytes, Macrophages and dendritic cells
Lymphocytes: T and B cells
What is systemic immunity and its role
A second line of defence past the skin, protection of internal environment
Defence within blood circulation via. Antibodies, cellular immunity
Does NOT induce mucosal immunity
What is mucosal immunity
The first line of defence i.e skin
How do most pathogens initiate infection?
Examples
By the mucosal surface (gastointestinal, urogenital, respiratory tracts)
E.g Influenza, tuberculosis , STD, Cholera and diphtheria
What is the components of the mucosal immune response and its affects on systemic immunity
IgA, T-cells.
Induction of mucosal immunity induces systemic immunity aswell.
What is humoral response?
The activation and proliferation of specific antibodies secreted by B-cells effectively combating infections.
Give an overview of humoral immune response
1) Activation - MACROPHAGE engulfing antigen by phagocytosis. the engulfed antigen is a phagosome. Antigens are usually marked by IgG
2) Lysosomes digest the phagosome, this is called ANTIGEN PROCESSING
3) Display (antigen presentation) - Class II MHC proteins combine and the MHC II displays the processed antigen
4) Helper T-cell : T cell combines to MHC II class protein and antigen. Macrophage will then release interleukin-1 which activates the helper T-cell
5) Activated T-cell will release its own cytokine which stimulate itself to proliferate with the same receptors specific for the antigen
What is the Humoral response effector phase?
Give an overview
part 2 of humoral immune response
Utilization of IgM receptors on B-cells.
This produces antibodies that bind and inactivate antigens.
Overview:
1) IgM binds to antigen and engulfed by endocytosis
2) Fuse lysosomes, digestions to fragments
3) MHC II attatchment and display
4) Helper T-cell binding with the same antigen specificity
5) T-cell release cytokine to stimulate B-cell to divide and produce clones
6) The clones produced can be plasma cells or memory cells
What are plasma cells
Cells that secrete antibodies, the same as the parent B-cell (originator). These antibodies bind and inactivate antigen.
What is cellular immune response
(Perforin)
Give an overview
A response system against infected cells by viruses or cancerous. This is done by cytotoxic T-cells what contains perforin. There is an activator phase and effector phase.
Overview:
1) Entry of virus, infection
2) Digestion, MHC I attatchment
3) Tc cell binds to cell and MHC I, antigen.
4) Tc proliferates with T-cell receptors specific for antigen
5) Infected cells present antigen via MHC I, this is marked for destruction.
6) Tc cells bind and secrete perforin, poking holes in the plasma membrane and causing cell to lyse.
What are the principles of vaccination
The more similar the vaccine is to the antigen, the better induced immune response.
Safe and must not cause undue harm
What is active immunity?
Protection produced by the persons own immune system, usually permanent.
