Immunity and disease Flashcards
What is immunity?
Protection against bacteria, fungi and virus
What does the immune system do?
Distinguishes non-self molecules from self ones
Name the 2 main pathways…
Innate
Adaptive
Give examples of innate immunity defence mechanisms?
Skin Mucosa Phagocytic cells Inflam Fever
Name non-specific defences…
Intact skin
Muscosa
Cillia
The outer layer of the skin acts as a…
Mechanical barrier
What contains anti-microbal chemicals on our skin?
Sweat and oils
What do interferon proteins do?
Inhibit the replication of viruses
What do granulocytes do in phagocytosis?
Remove dead cells and microorganisms
WBC are attracted to the site how?
From inflammatory response of damaged cells
Macrophages also help in phagocytosis, true or false?
True
Name the non-specific responses to infection…
Fever Redness Swelling Pain Acute phase proteins released from liver
Why does a raised temp try to protect us?
Because most bacteria grows below body temp
Why are acute phased proteins released from liver?
To bind to bacteria and activate complement proteins
What protein signals to macrophages releasE?
Interleukin 1 & 6
Where are lymphocytes produced?
Bone marrow
When B&T cells mature they circulate where?
Blood and lymph
Why is it beneficial for B&T cells to be in circulation?
So they come into contact with pathogens & each other
Where do B cells mature?
Bone marrow
What do B cells do?
Secrete anti-bodies
Which cell is involved in humoral immunity?
B
Which cell is involved in cell-mediated immunity?
T
What do cytotoxic T cells do?
Seek out and destroy any antigens in the system (some can target cancer cells)
What to helper T cells do?
Stimulate B cells to produce antibodies
Activate cytotoxic T cells and macrophages to attack infected cells
How do T cells recognise an invader?
Macrophage identifies a non-self protein first and takes it to helper T cell and if helper T cell knows its not self, immune response is launched (see diagram)
HIV destroys what?
Helper T cells- immune response therefore poor
B cells differentiate into what?
Plasma cells that produce antibodies
Memory cells e.g. chicken pox
Immunodeficiency means people are…
Prone to infections
Over reactive immune systems lead to…
Hypersensitivity reactions
Failure to recognise self leads to…
Auto-immune diseases
What can cause immunodeficiency?
HIV
Chemo/drugs
Splenectomy
Bone marrow dysfunction
What can cause hyperactivity?
Allergy
Auto-immunity
Overreaction to pathogen
Which cells does HIV affect?
CD4 +T
What are the HIV stages of progression?
Infection
Latency
Aids
Define secondary immunodeficiency…
Caused by outside factors e.g. HIV/chemo
Causes of secondary immunodeficiency?
Malnutrition Burns Uremia Diabetes mellitus Immunotoxic meds AIDS Alcohol/self med of recreational drugs
Over reaction to a pathogen is called…
Systematic inflammatory response syndrome
Examples of hypersensitivity
Asthma
Hay fever
Peanut allergy
Examples of autoimmune diseases
Diabetes
MS
Coeliac disease
Hashimoto’s Thyroiditis
How can we manipulate the immune system?
Organ transplant
Vaccine
E.g. of live vaccine (live weakened pathogen)
MMR
E.g. of inactivated vaccine (inactive part of pathogen)
Hep B
E.g. of toxoid vaccine (bacterial toxin)
Diptheria
E.g. of conjugated vaccine (antigen linked to protein carrier)
Pneumococcal
