REAGENT or RESOURCE	SOURCE	IDENTIFIER
Antibodies
Horse anti-mouse HRP	Cell Signaling Technology	Cat# 7076S RRID:AB_330924
Mouse anti-myc mAb	Cell Signaling Technology	Cat# 2276S RRID:AB_331783
Goat anti-mouse IgG+IgM	Jackson ImmunoResearch	Cat# 115-005-068 RRID:AB_2338453
Mouse IgG1 lambda isotype control	BD Biosciences	Cat# 553485 RRID:AB_479649
Anti-mouse Fc Block	BD Biosciences	Cat# 553142 RRID:AB_394657
Anti-mouse B220 BUV737	BD Biosciences	Cat# 612838 RRID:AB_2738813
Anti-mouse CD3 PerCP-Cy5.5	BD Biosciences	Cat# 551163 RRID:AB_394082
Anti-mouse CD138 BV650	BD Biosciences	Cat# 564068 RRID:AB_2738574
Anti-mouse CD38 Alexa Fluor 700	Thermo Fisher Scientific	Cat# 56-0381-82 RRID:AB_657740
Anti-mouse GL7 ef450	Thermo Fisher Scientific	Cat# 48-5902-82 RRID:AB_10870775
Anti-mouse IgM BV786	BD Biosciences	Cat# 743328 RRID:AB_2741429
Anti-mouse IgD BUV395	BD Biosciences	Cat# 565988 RRID:AB_2737433
Anti-mouse CD73 PE-Cy7	Thermo Fisher Scientific	Cat# 25-0731-82 RRID:AB_10853348
Anti-mouse CD80 BV605	BD Biosciences	Cat# 563052 RRID:AB_273795
Biological samples
BALB/c mice	Jackson Laboratory	Cat# 000651
Chemicals, peptides, and recombinant proteins
AddaVax adjuvant	InvivoGen	Cat# vac-adx-10
ABTS	ThermoFisher	Cat# 37615
TMB	SeraCare	Cat# 5120-0083
EZ-Link Sulfo-NHS-LC Biotinylation Kit	ThermoFisher	Cat# 21435
Streptavidin-APC	Agilent	Cat# PJ27S-1
Streptavidin-PE	Agilent	Cat# PJRS25-1
Anti-PE Micro-Beads	Miltenyi Biotec	Cat# 130-048-801
Anti-APC Micro-Beads	Miltenyi Biotec	Cat# 130-090-855
DyLight 755 Antibody Labeling Kit	ThermoFisher	Cat# 84538
Alexa Fluor 647 Protein Labeling Kit	ThermoFisher	Cat# A20173
Experimental models: Cell lines
Expi293F	ThermoFisher	Cat# A14527
MDCK-SIAT-PB1	Creanga et al.98	N/A
Recombinant DNA
See Table S1 for amino acid sequences.
Software and algorithms
UCSF ChimeraX	Goddard et al.99	https://www.rbvi.ucsf.edu/chimerax/
Prism	GraphPad	https://www.graphpad.com/scientific-software/prism/
FlowJo v10	FlowJo	https://www.flowjo.com
RosettaScripts “sugarcoat” code	Adolf-Bryfogle et al.1	N/A
Other
EM supplies 300 mesh grids	Ted Pella	Cat# 01843-F
Filter paper	Cytiva	Cat# 1004047
Uranyl formate	SPI Chem	Cat# 02545-AA
Superdex 200 Increase SEC column	Cytiva	Cat# 28-9909-44
Superose 6 Increase SEC column	Cytiva	Cat# 29091596
Talon resin	TaKaRa	Cat# 635652
Excel resin	Cytiva	Cat# 17371203
Isoflurane	USP Patterson	Cat# 07-893-1389
EndoSafe LAL Test Cartridges	Charles River Labs	Cat# PTS20005F
Lemo21(DE3)	New England BioLabs	Cat# C2528J
Isopropyl-B-D-thiogalactoside (IPTG)	Sigma-Aldrich	Cat# I6758
Kanamycin Sulfate	Sigma-Aldrich	Cat# K1876
HisTrap FF	Cytiva	Cat#17525501