Bcells and Tcells working together

Bcell activation: Signal 1 involves

BCR engagement

Bcell activation: Signal 2 involves

TLR Toll-like receptor (Thymus Independent antigen)

OR

MHC2/T_FH (linked recognition) + CD40L/CD40(Tcell help) (Thymus Dependent antigen)

Bcell activation: Signal 3

Cytokines (IL21, IL6, IL4, IFNy, and TGF-B)

Where does Tcells and Bcells interact

Secondary organs, Spleen

What are the areas of the spleen

Tcell zone and the follicle

When Bcells are in follicles what do they express

CXCR5

In the spleen, the Follicle dendritic cell (FDC) produce ________ and binds to _____ on bcell, this attracts the Bcell

produce CXCL13 and binds to CXCR5

In the spleen Dendritic cells produce ______ and binds to ______ on tcells, this attracts the tcell

produce CCL21 and binds to CCR7

Activated bcells induce ____ (on tcell)and Tcells induce ______ (on bcell)

CCR7 and CXCL5

What causes the bcell and tcell to go to the follicular or interfollicular

after the bcell and tcell induce each other

What happens after the Tcell and Bcell meet at the follicular region

B cells mature

What activates and causes proliferation of the mature bcell (TD)

(TD) antigen, Tcell help, T_FH

What are the two different pathways for mature bcells after they proliferate/activate in the spleen

1. Stay in or out of the Follicular region, NO T_FH interactions

2. Remain in follicle, T_FH close association

Two types of Bcells that are outcome of no T_FH interaction

Plasmablasts and Plasma cells

Plasma Cells are in 1._____ and primary function is to 2.______ _______

1. Follicle

2. Produce immunoglobins (isotype switching) One cell produce one type of antibody

3. LONG lived

4. Can NOT divide

Plasma Blasts are located in the 1._____ and main purpose is 2._______

1. Primary Focus

2. Short-lived (3-4days)

3. Produce IgM, IgD

4. Can divide

What do the bcells differentiate into if they STAY in the follicle and associate with the T_FH cells

Germinal Center (GC) B-cells

Memory plasma cells that are made go to the _____

Bone marrow

TI antigens cause mature bcells to become

Plasma Cell