9 - Host defence Overview

Question 1

What are zoonoses?

Answer 1

infectious diseases of animals

Question 2

What are the modes of transmission of disease (from person to person)?

Answer 2

• respiratory of salivary spread
• faecal-oral spread
• venereal spread (STDs)

Question 3

special features of the airway and lungs

Answer 3

• shares the pharynx with the GI tract
• rapid epithelial turnover
• filters blood volume every minute
• dissociated lymphocyte division (lymph nodes)
• endopulmonary lymphatic circulation
• IgA is important in the lung

THE LUNG HAS TIGHT IMMUNOREGULATION

Question 4

What are the surface defences against infection?

Answer 4

• coughing
• sneezing
• mucus
• cilia
• rapid cell turnover
• walls of dead cells

Question 5

When are interferons produced?

Answer 5

they are the first line of defence against viruses

when PAMPs and DAMPs are recognised, the cells produce interferons and a wave of information spreads out

Question 6

What is a typical immunoglobulin response to vaccines?

Answer 6

IgM is the first to respond

IgG response persists

Question 7

What are the defences against bacteria?

Answer 7

• surface defences
• antibody opsonisation
• complement - causing lysis/opsonisation
• phagocytosis
• release of inflammatory mediators and acute phase proteins
• fever

Question 8

What are the defences against viruses?

Answer 8

• surface defences
• INTERFERONS
• inflammatory mediators and acute phase proteins
• NK cells
• antibody, complement, ADCC (acute dependent cell-mediated toxicity)
• T cells

Question 9

What are the mucosal defences?

Answer 9

• mannan binding proteins
• antimicrobial peptides
• enzmyes e.g. lysozymes
• mucosal lymphocytes
• secretory IgA