Lecture 1 Flashcards
(33 cards)
pathogen , commensals and opportunistic pathogen def
path= micro-organism with the potential to cause disease
commensals= micro-organisms with which we co-exist and which are essential to our wellbeing
opportunistic pathogens=normally not disease causing but becomes pathogenic under certain conditions
first vaccine
by edward jenner, small pox in 1796
vaccination prepares IS to eradicate an infectious agent before it causes disease
Define
where is the is
MADE IN BM AND TRANSFERRED EG LYMPH SYSTEM AND BLOOD
innate IS description
-inbuilt immunity to resist infection
-present from birth
- not specific for any microbe-generalist
-not enhanced by second exposure ie no memory
-uses cellular and humoral components
- is much less effective without adaptive IS (in vertebrates).
-involved in amplifying and triggering adaptive immune responses
-essential for survival- nonfunctional innate IS= fatal
Define
Haematopoeisis outline
What are the two complementary systems in vertebrates (IS)
how do effectors such as leukocytes that are phagocytic contribute to innate immunity
PHAGOCYTIC CELLS
-first line of defense after mucus and epithelium (recognises bacteria by surface receptors)
-phagocytosis is driven by a variety of receptors eg mannose receptor, glucan and LPS receptor (CD14)
-phagocytic cells= neutrophils in blood and macrophages in blood and tissues. They engulf and or release chemical messengers like cytokines to amplify Immune response
-kill by- acidification, reactive oxygen species (eg O2-,H2O2 and OH), nitric oxide (NO) and enzymes eg lysozyme / acid hydrolases
Factors (effectors) that make innate IS work - think humeral and cellular
4 effectors for pathogen apocalypse
Name effectors of innate IS
Describe how epithelial cells and mucus secretion contributes to innate is
Skin= barrier, pathogen can only enter when breached eg wound or burn
Mucosal epithelia = eg airways and gut secrete mucus and have beating cilia that causes mucus flow and expulsion of micro org
describe the types of phagocytic cells
NEUTRAPHIL
-very short lived cells 5d-6d
-very common 50-70% of circulating WBC
-normally present in blood
-recruited to sites of infection by inflammation
-Phagocytic and produces chemical mediators
-neutropenia (lack of neut) results in overwhelming infection
-critical for both adaptive and innate IS
MONOCYTES and MACROPHAGES
-3-8% of WBC
-largest WBC
-go into tissues and become macrophages
-similar function to neutrophils but longer lived
-important in later stages of inflammation eg healing
-can have pro-inflammatory or anti inflammatory
- are professional APC (antigen presenting cell)- important for adaptive IS
Effectors of innate immunity- what is complement / opsonisation
Define and describe Effectors of immunity cytokines
CYTOKINES
-hormones for leukocytes
- proteins that regulate Immune cells ; growth, differentiation, activation and recruitment
-subclasses; lymphokines, interleukins, chemokines and interferons
Do cytokines act locally or systemically
Which image shows inflammation - explain
What are the consequences of inflammation
Describe inflammation process by innate immune system
Innate and adaptive recognition - how does the IS know when to respond
Define PAMPS & DAMPS
What are the three types of innate sensors for recognising foreign bodies
What’s more recently developed adaptive or innate immunity
