2.5.10 infection process

Question 1

which has a greater SA, outer skin or mucosal surfaces?

Answer 1

mucosal

Question 2

which are the encapsulated organs with both diffuse lymphatic tissue and lymphatic nodules?

Answer 2

Lymph nodes, thymus, spleen

Question 3

describe discrete lymphatic tissue

Answer 3

• can be 2-3 cells, nodule, or germinal center
• can be nodular (has germinal centers) or non-nodular
  -HIGH ratio of lymphocytes to other cells

Question 4

describe Diffuse lymphatic tissue

Answer 4

• LOW ratio of lymphocytes to other cells
• in GI or upper respiratory
• 2 or 3 lymphocytes interacting with each other

Question 5

what category do MALT, GALT and BALT fall into?

Answer 5

secondary lymphoid tissue

Question 6

_____ are very diffuse and transient (come and go as infection does)

Answer 6

MALTs

Question 7

what are examples of discrete lymphoid tissue? are they temporary or permanent?

Answer 7

GALTs and BALTS
Permanent

Question 8

_____ allow liquids to remain inside and also carry agglutinated molecules away

Answer 8

Mucin molecules

Question 9

the tonsils and adenoids form a ring of lymphoid tissues called _______ around the entrance of the gut and airway

Answer 9

Waldeyers ring

Question 10

what does the GI tract consist of?

Answer 10

Commensals, s-IgA, Mucus

Question 11

what are some of the things that commensal micro-organisms can do? (5)

Answer 11

1. synthesize essential metabolites like Vitamin K
2. break down plant fibers in food
3. inactivate toxic substances in food or from pathogens
4. prevent pathogens from benefitting from resources of human gut
5. trigger immune response across epithelial border

Question 12

In peyers patches, what cell brings in bacteria from gut lumen to GALTs?

Answer 12

M cell

Question 13

Once antigens are brought into peyers patches, what happens?

Answer 13

dendritic cells and lymphocytes are waiting, B-cells and T-cells look for interactions so they can differentiate into effector T-cells or plasma cells

Question 14

______ can extend processes across the epithelial later to capture antigen from the lumen of the gut

Answer 14

dendritic cells

Question 15

Native lymphocytes that are activated in Peyers patch give rise to _____ that travel in the _____ and go out to the ________

Answer 15

• effector cells
• lymph/blood
• mucosal tisssue

Question 16

what are cells found in mucosal tissue?

Answer 16

effector leulocytes, CD8, CD4, plasma cells, dendritic cells, mast cells, dendrites

Question 17

do we want to produce inflammation in the bowel?

Answer 17

NO

Question 18

from blood vessels, effector T-cells bind to intestinal vascular endothelium and enter the _________. Here the T- cells bind to _______

Answer 18

• lamina propria
• chemokines expressed by intestinal epithelium (CCL25)

Question 19

s-IgA has multiple mechanisms and they are all _______

Answer 19

non-inflammatory

Question 20

what are s-IgAs different mechanisms?

Answer 20

1. export toxins and pathogens from lamina propria while being secreted
   2.bind and neutralize antigens in endosomes
2. can bind and neutralize pathogens and toxins on gut surface
3. secreted IgA can bind pathogen on M-cell and take it to lymphoid tissue
4. Lymphoid IgA picks up antigen in endosomes and takes it to lymphoid tissue

Question 21

____ has a long fold region that is subject to proteases, _____ has a short fold region that wont get proteased.

Answer 21

IgA1
IgA2

Question 22

If there is a lack of ability to produce IgA, more what is produced?

Answer 22

IgM

Question 23

Secretory _______ (2) protects mucosal surfaces from microbial invasion

Answer 23

IgM, IgA

Question 24

IgG being transported from the blood —> lamina –> gut lumen by ______ is considered ______ (passive or active)

Answer 24

FcRn
- passive NOT active

Question 25

what is an example of innate immunity on mucosal surface cells?

Answer 25

NOD2 proteins in cytosol of RBC

Question 26

NOD2 proteins in cytosol of RBC respond to bacterial products by activating _______ ( just like TLRs)

Answer 26

NFkappaB

Question 27

Bacteria are recognized by _______ on cell surface or intracellular vesicles, while _______ recognize bacteria entering the cytosol

Answer 27

TLR NOD1, NOD2

Question 28

what kind of response do we want against worms? why?

Answer 28

antibody, cellular response can damage the host

Question 29

______ triggers protective antibody responses against worms while _____ triggers a harmful cellular response

Answer 29

TH2 TH1

Question 30

the secondary response is ________ than primary response

Answer 30

stronger, more specific

Question 31

the majority of T-cell and B-cells that are activated become _________, but the minority becomes ________

Answer 31

1. short lived effector cells ( effector T and plasma ) 2. long lived memory cells

Question 32

______ antibody amount increases with each infection. _____ antibody increases exponentially, while ______ affinity doesnt change much at all

Answer 32

IgG IgG IgM

Question 33

In primary response _____ binds to pathogen and there is production of ______

Answer 33

-Naive B cell -low affinity IgM antibodies

Question 34

In secondary response _____ binds to pathogen coated with antibody and there is production of ______

Answer 34

- naive b cell (activation prevented) and Memory B cell - production of high affinity IgG, IgA, IgE

Question 35

what is an example of how memory response can be detrimental?

Answer 35

If a Rh- mother carries an Rh+ fetus, then becomes pregnant with another RH+ fetus

Question 36

how can B-cell memory response be evaded?

Answer 36

antigen changes epitopes

Question 37

_____ remains around longer than an antibody molecule

Answer 37

T-cell memory

Question 38

_______ affects memory surface markers

Answer 38

mRNA splicing

Question 39

how do you recognize a naive CD4 T cell?

Answer 39

it has CD45RA that has ABC in gene transcript

Question 40

how do you recognize a memory/effector CD4 T cell?

Answer 40

it has CD45RO that excludes ABC (have been spliced out)

Question 41

when memory cells are directly activated from naive T-cells _____ turns into ______. these cells go on to be _____ & _____

Answer 41

CD45RA --> CD45RO -central memory cells that express CCR7 and effector memory cells that LACK CCR7

Question 42

where do central memory cells with CCR7 go?

Answer 42

remin in lymphoid tissue

Question 43

where do effector memory cells without CCR7 go?

Answer 43

migrate to tissues

Question 44

some effector cells become _______ and most effector cells ____

Answer 44

-quiescent memory cells -die after a few days

Question 45

where are gamma/delta T-cells located?

Answer 45

near epithelial tissue

Question 46

____ are MHC class 1-like molecules that bind gamma/delta receptors and induce infected cell to die from apoptosis

Answer 46

MICs

Question 47

how do MIC and NK cells work together to kill infected cells?

Answer 47

- MHC1 + NK cell = no killing of cell -MIC + NK cell = killing of cell