basic sci

Question 1

name two signals needed for IgE class switch

Answer 1

1) Il 4 or il 13 (this phosphorylates STAT6, which activates the episilon germline transcription upstream of constant epsilon region)
2) cd40 ligand to activate cd40 on b cell which will activate NFkb which activates AID (UNG and APE1) which helps splice and make nics to join the Switch regions

then the DSBR - artermis, ligase 4 and ATM brings the switch regions together and takes on introns

Question 2

whats the target of omalizumab

Answer 2

C epsiolin 3

Question 3

what is the target of dupi

Answer 3

il4 receptor alpha

this is found on both tpye 1 and type 2 il4 receptors
remember il 4 receptor 1 only binds il4 (has the gamma)

type 2 binds both il4 and il13

Question 4

name two inhibitors of ige

Answer 4

il21, and inteferon gamma

il21 increases bcl6 which competes with stat 6
SOCS also dec il4

Question 5

name 4 reactions occured with herbal meds

Answer 5

Bee pollen can cause anaphylaxis
Echinacea - can cause anaphylaxis and asthma
Chinese herbs - TEN and cutaneous reactions

Question 6

which enzyme is deficient in anticonvulsant syndrome

Answer 6

epoxide hydrolase

occur wirh phrnytoin, phrnobarbitol and carbamazepine

altenratives u can use are VPA, gabapentin and lamotirigine

tend to present slower - skin nodules, plaque and LAD (confused with pesudolymphoma)

Question 7

define drugs and asscoiation wiht systmeic vs cutaneous induced SLE

Answer 7

systmeic - antihistone bodies are present, procanaimide and hydralazine

cutaneous - no antihistone. anti ro and la. CCB, ACE inh and propylthiouracil and statin

Question 8

Name the signals needed for t cell activation

with B cell, binding of MHC causes T cell to express CD40 L
and this binds CD40 on B cell causing class switch from IgM

Answer 8

1) TCR binds to the peptide
CD3 supports this (alpha gamma, episolonx2)

CD4/8 locks onto the MHC

2) costim CD80/86 to CD28 (2nd signal)

hours later ctla4 binds to the cd80/86 wiht higher affinity

Question 9

three dif btwn mch1 and 2

the class 3 is for tnfalpha and complelemetn

Answer 9

mch1:
has b2microglobulin and 3 alpha
smaller peptide 8-9
intracellular organisms
HLA abc
present to CD8

mhc2
has 2alpa 2 beta
has peptide 12aa
extracell
HLA dr dq dp
present to cd4

Question 10

five diff btwn cholinergic urticaria and EIan

Answer 10

1) cholinergic occurs with any inc in body temp just not exercise
2) chol has smaller uritcaria and limited to skin
3) treat chol with antihis vs Eian is epi
4) chol has positive tests like passive heat chall, autologous sweat skin test, ID methacholine chall)
5) EI can also be depnedant on food