L35 Patho of MS

Question 1

common sxs of MS (theres a ton)

Answer 1

visual problems
numbness
fatigue
motor weakness
gait problems
pain
spasticity
dizziness/vertigo
sexual dysfunction

Question 2

main virus thought to be involved in developing MS

Answer 2

epstein barr virus

Question 3

through what mechanism does the epstein barr virus cause MS?

Answer 3

molecular mimicry

Question 4

True or False: Genetics play an important role in the development of MS

Answer 4

True

Question 5

what are the 3 different types of MS

Answer 5

Relapsing-remitting MS (RRMS)
Secondary progressive MS (SPMS)
Primary Progressive MS (PPMS)

Question 6

Relapse Remitting MS (RRMS)
- involves ….
- multifocal areas…
- initial sxs ….
- most cases….

Answer 6

• involves relapse of neurological dysfunction lasting weeks or months and affecting the brain, optic nerves and/or spinal cord
• multifocal areas of damage are revealed by MRI in the white matter
• initial sxs disappear, but less remission with each relapse
• most cases of RRMS eventually enter SPMS

Question 7

Secondary Progressive MS (SPMS)
- characterized by ______
- involves ______

Answer 7

• less inflammation than RRMS
• involves slowly progressive neurological decline and CNS damage, with little remission

Question 8

Primary Progressive MS (PPMS)
- resembles ___
- Mean age ____

Answer 8

• resembles SPMS at initial stage
• of onset is alter than RRMS bc inflammatory episodes of RRM S surpass the symptomatic threshold

Question 9

know the figure on slide 8/20

Answer 9

okay i will be sure to go take a look at it

Question 10

what is CIS?

Answer 10

Clinically isolated syndrome
- initial episode of neurologic sxs lasting >24 hours
- inflammation and demyelination in optic nerve, cerebrum, cerebellum, brainstem or spinal cord
- most cases progress to MS

Question 11

What does the progressive phase of MS involve?

Answer 11

cytodegeneration (loss of myelin, axons, oligodendrocytes) and occurs with a similar rate in different forms of MS

Question 12

what is the overall clinical presentation of MS determined by?

Answer 12

combo of underlying degeneration and the host’s immune reaction to it

Question 13

first step autoimmune phase of MS

Answer 13

• antigens released from CNS or cross-reactive foreign antigens are presented to B and T cells in the lymph nodes

Question 14

Degenerative phase of MS (2 things)

Answer 14

• CNS damage is triggered by activated B and T cells or by other insults such as stroke or infection
• antigens released from damaged sites in the CNS further prime immune cells in the periphery

Question 15

T or F: the degenerative phase triggers MS

Answer 15

F, it is unclear which phase does it

Question 16

second step autoimmune phase of MS

Answer 16

• B and T cells with high-affinity receptors for these antigens are expanded and migrate to CNS cites where they re-encounter and are activated by their target ligands

Question 17

third step autoimmune phase MS

Answer 17

• activated B and T cells then carry out immune fxns at the CNS sites

Question 18

autoimmune responses in MS:
what activates T cell responses in the peripheral lymphoid tissue?

Answer 18

dendritic cells

Question 19

autoimmune responses in MS:
what allows for activated B and T cells to proliferate and infiltrate the CNS?

Answer 19

a4-integrin mediated binding and penetration of the BBB

Question 20

autoimmune responses in MS:
what happens to B cells that re-encounter their specific antigen in the CNS?

Answer 20

they mature to plasma cells and release IgG antibodies that target the antigen on expressing cells

Question 21

autoimmune responses in MS:
what do T cells do during this part lol

Answer 21

interact with their target ligands presented by oligodendrocytes, neurons, or microglia on MHC molecules

Question 22

autoimmune responses in MS:
T cell activation results in _______ and ________, leading to damage in myelin sheath

Answer 22

cytokine release and macrophage stimulation

Question 23

demyelinated regions can be. repaired via _____?

Answer 23

remyelination (no shit)

Question 24

remyelination involves the recruitment of ____ to the lesion and the differentiation of these cells into myelin-producing ____________

Answer 24

OPCs and oligodendrocytes

Question 25

why does remyelination typically fail in MS?

Answer 25

lack of OPCs or a failure of OPCs to differentiate

Question 26

what is astrogliosis?

Answer 26

the invasion and propagation of astrocytes, resulting in irreversible formation of gliotic plaques or scars

Question 27

demyelination is the loss of what two things?

Answer 27

myelin and oligodendrocytes

Question 28

what does demyelination result in?

Answer 28

activation of microglia and astrocytes

Question 29

what do activated microglia and astrocytes release?

Answer 29

pro-migratory factors and mitogens that recruit OPCs to the lesion and stimulate their proliferation

Question 30

what eliminates myelin debris?

Answer 30

macrophages

Question 31

what do recruited OPCs do?

Answer 31

differentiate into oligodendrocytes

Question 32

what is the key step where remyelination fails in MS?

Answer 32

OPC differentiation

Question 33

T or F: myelin sheath formed after remyelination is identical to its original form

Answer 33

F, they are thinner and shorter

Question 34

3 treatment options for Guillain-Barre syndrome

Answer 34

ventilation
plasmapheresis
IV immunoglobulin administration