REAGENT or RESOURCE	SOURCE	IDENTIFIER
Antibodies
Anti-B220	Biolegend	RA3-6B2. Cat#103241; RRID: AB_11204069
Anti-B220	Biolegend	RA3-6B2. Cat#103246; RRID: AB_2563256
Anti-Bcl6	BD	K112-91 Cat#561522; RRID: AB_10717126
Anti-Bcl6	BD	K112-91. Cat#561525; RRID: AB_10898007
Anti-CD4	Biolegend	RM4-5. Cat#100547; RRID: AB_11125962
Anti-CD4	Biolegend	RM4-5. Cat#100528; RRID: AB_312729
Anti-CD4	ThermoFisher Scientific	GK1.5. Cat#17-0041-83; RRID: AB_469320
Anti-CD4	ThermoFisher Scientific	GK1.5;. Cat#48-0041-82; RRID: AB_464893
Anti-CD4	ThermoFisher Scientific	GK1.5;. Cat#11-0041-85; RRID: AB_464892
Anti-CD4	ThermoFisher Scientific	GK1.5. Cat#48-0042-82; RRID: AB_1107001
Anti-CD4	ThermoFisher Scientific	GK1.5. Cat#45-0042-82; RRID: AB_1107001
Anti-CD44	Biolegend	IM7. Cat#103020; RRID: AB_493683
Anti-CXCR5	Biolegend	L138D7. Cat#145506; RRID: AB_2561970
Anti-CXCR5	Biolegend	L138D7. Cat#145512; RRID: AB_2562128
Anti-Foxp3	ThermoFisher Scientific	FJK-16S. Cat#53-5773-82; RRID: AB_763537
Anti-Foxp3	ThermoFisher Scientific	FJK-16S. Cat#48-5773-82; RRID: AB_1518812
Anti-Ki67	ThermoFisher Scientific	SolA15. Cat#56-5698-82; RRID: AB_2637480
Anti-Ki67	ThermoFisher Scientific	SolA15. Cat#11-5698-82; RRID: AB_11151330
Anti-Ki67	ThermoFisher Scientific	SolA15. Cat#25-5698-82; RRID: AB_11220070
Anti-PD-1	Biolegend	RMP1-30. Cat#109104; RRID: AB_313421
Anti-PD-1	Biolegend	RMP1-30. Cat#109110; RRID: AB_572017
Anti-IgG1	Abcam	Cat#ab97240; RRID: AB_10695944
Anti-IgM	Abcam	Cat#ab97230; RRID: AB_10688258
Anti-IgG	Abcam	Cat#205719; RRID: AB_2755049
Anti IgE	BD Biosciences	Cat# 553419; RRID: AB_394850
Anti-Foxp3	eBioscience	FJK-16s. Cat # 53-5773-80; RRID: AB_469916
Anti-IgD	BioLegend	11-26c.2a. Cat# 405707; RRID: AB_893529
Anti-Ki67	eBioscience	SolA15. Cat #48-5698-82; RRID: AB_11149124
Anti-CD3e	eBioscience	eBio500A2. Cat# 14-0033-82; RRID: AB_837128
Goat anti-Hamster IgG (H+L)	Invitrogen	Cat# A-21112; RRID: AB_2535761
Anti-CCR7	ThermoFisher Scientific	4B12. Cat# 12-1971-82; RRID: AB_465905
Anti-CXCR4	Biolegend	L276F12. Cat# 146506; RRID: AB_2562783
Bacterial and Virus Strains
A/HK/x31 (H3N2)	A gift from Prof. Douglas Fearon	N/A
Chemicals, Peptides, and Recombinant Proteins
NP-KLH Conjugation ratio 29-33	Biosearch Technologies	cat#N-5060
Imject Alum Adjuvant	ThermoFisher Scientific	cat#77161
Brilliant Stain buffer	BD Horizon	cat#563794
Zombie aqua fixable viability dye	Biolegend	cat# 423101
NP7-BSA	Biosearch Technologies	cat#N-5050L-100
NP20-BSA	Biosearch Technologies	cat#N-5050H-100
Critical Commercial Assays
eBioscience Foxp3/ Transcription Factor Fixation/Permeabilisation Staining buffer set	ThermoFisher Scientific	cat# 00-5523-00
3,3′,5,5′-Tetramethylbenzidine (TMB) substrate set	Biolegend	cat#421101
Deposited Data
RNA-sequencing data from Wing et al., 2017	Wing et al., 2017	https://www.ncbi.nlm.nih.gov/bioproject/PRJDB5396; https://www.ncbi.nlm.nih.gov/bioproject/PRJDB4935
Experimental Models: Organisms/Strains
Mouse: Cxcr5fl/fl	Roslin Institute	Bradford et al., 2017
Mouse: Foxp3cre-yfp	JAX	Rubtsov et al., 2008. Stock No: 016959
Mouse: Foxp3EGFP-cre-ERT2	JAX	Rubtsov et al., 2010. Stock No: 016961
Mouse: Cd4cre	Taconic Biosciences	Lee et al., 2001. Model#4196
Mouse: Cxcr5fl/fl Foxp3cre-YFP	This paper	N/A
Mouse: Cxcr5fl/fl Foxp3EGFP-cre-ERT2	This paper	N/A
Mouse: Cxcr5fl/f Cd4cre	This paper	N/A
Software and Algorithms
FlowJo	Treestar	https://www.flowjo.com/
Volocity	PerkinElmer	https://www.perkinelmer.com/category/image-analysis-software
Graphpad Prism	Graphpad	https://www.graphpad.com/
Other
16% global protein rodent diet	Teklad	cat#2916
CRD TAM400/CreER Tamoxifen pellets	Teklad	cat#TD.130860