Chapter 7 Flashcards
Double neg thymocytes initiate rearrangement at the
B, gamma , gamma loci before all other T cell receptor genes
Function of neg selec in the thymus is to elimate
Autoreactive thymocytes
If TCR on a double pos thymocyte binds to a self peptide : self MHC I complex with LOW AFFINiTY
Results in pos selec of CD8 TC
In adults the mature TC repertoire is self renewing and does not require a thymus for provision of new TC
Correct
AIRE def
Exhibit APECED
TC analog of VpreB: lambada 5
Protein preTa (pTa)
Pta
Also binds like imm heavy chain binds to CD3 an zeta - assemble indices TC prolif and rearrangement of TCR beta leading to allelic exclusion
TC k pt
- Occurs after the rearrangement of the beta chain locus which test the ability of the beta chain to ass with pta, the surrogate light chain, and for the Pre -TCR on the surface
- After rearrangement of alpha chain locus test the ability of the alpha chain to associate with the b chain and for the TCR on the surface
MHC II expression
APC cells
To produce an antibody
Require TC in the form of cytokines produced by CD4 TH2 cells
Role of regulatory CD4 cell
T reg
They suppress the proliferation of naive auto-reactive CD4 TC by secreting inhibitory cytokines.
Require both Treg and the other CD4 are interacting with the same APC
TC are derived from
BM stem cells
Lymphoid progenitor cells in the
Thymus- initiation of TC devel
Things we have to select for in TCD
Host MHC
CD4 or CD8
Overview of TC devl
Thymus unit of TCD TCR speciality -VDJ recom MHC restriction-pos selec Selection of -TH or cytoxic Elimination of self spec TC-neg sele
TC linage
A:b
G:d
Thymus contain what precursor
Contains thymocytes =precursors
Thymus organization
Cortex = immature thymocytes
-enter by HEV then start in cortex
Medulla= mature thymocytes
-selection occurs, mature TC
No thymus means what cells
No T cells but yes BC but they would not function bcuz BC need helper TC
No thymus what syndrome
DiGeoegr
No thymus dev
Normal BC
Symptoms of SCID
Removal of thymus
A thymectomy
-only in adults
Auto imm
TC lineage
Interaction bw stromal cells
Signaled to divide
Committed
Double neg- bcuz they do not have CD4 or CD8
What regulates TCD
IL-7
Notch 1
What is IL-7
Binds to receptor on cd34
Import for reg of TCD