contemplating follicular T cells and B7-2

The B7 ligands inform the T cell which pathway to take: to become follicular T cells or to become regulator Tcells  then as a T follicular to find a B cell to make antibodies. B7 when binding CTL-4 can also slowly stop the reactions.

Capture of Antigen by BCR of B cell from FDC
https://www.ncbi.nlm.nih.gov/pubmed/19506051

cd169 macrophages APC (these are the SCS of the lymph and the metallophillic macrophage of the spleen)
https://onlinelibrary.wiley.com/doi/full/10.1002/eji.201444983

THfollicular Th1 to Tfh1 or Th2 to Tfh2 ?
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2193096/

Does B7-2 on APC cause the conversion of Th1 or Th2 to the follicular type of T cell? Tfh1 and Tfh2?

B7-2 and follicular T cell development
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3089765/

B7-2 is on Langerhans, medial zone B cells, macrophages, and dendritic cells which bring the antigens to the lymph or spleen

B7-1 is on the follicular B cell that presents to the follicular T cell that with TCR stimulation activates the T cell and Icos is expressed.

(B7-1 is also on activated T cells and activated macrophages)

Pd-L is increased with ifn gamma on cd4 and cd8 cells so they can interact with the myeloid or plasmacytoid dendritic cells.

B7-DC(pd-L1) on myeloid dendritic

B7-H1 (pd-L2) plasmacytoid dendritic

B7-1 (cd80) follicular B cells which present

B7-2 (cd86)  Langerhans, macrophages, dendritic cells, and marginal zone B cells (antigen carriers)

where the Th1 is actually a follicular Th1 and the Tc is a follicular Tc.  Note that I am not showing the interaction of the inner antigens on the scs macrophages antigen presenting to the B cells BCR.

CD8 T cells becoming follicular like
https://www.ncbi.nlm.nih.gov/pubmed/29743314

The notion that B7-2 tells the T cells to become follicular is logistical. The antigen carrier wearing B7-2 informs the T cell that we have the antigen so please find an antigen presenter, a B cell and make antibodies with them.

in the absence of additional dendritic/antigen carrying cells  the T cells having seen APC can't make il-21 ( become follicular?)
https://www.ncbi.nlm.nih.gov/pubmed/21715693/

Is this the B7-2 ?

Tfollicular cells and autoimmune disease
https://www.bioportfolio.com/resources/trial/161554/Study-the-Role-of-T-Lymphocytes-in-Autoimmune-Hemolytic-Anemia.html