REAGENT or RESOURCE	SOURCE	IDENTIFIER
Antibodies
anti-IgG-APC	BD Biosciences	Cat# 550931; RRID: AB_398478
anti CD19-FITC	BD Biosciences	Cat# 340864; RRID: AB_400152
anti-human Fc-HRP	Sigma-Aldrich	Cat# A0170; RRID: AB_257868
Bacterial and virus strains
SARS-CoV-2 USA-WA1/2020	Harcourt et al., 2020	N/A
Biological samples
PBMC and plasma from SARS-CoV-2 convalescent donors	This paper	N/A
Chemicals, peptides, and recombinant proteins
Recombinant SARS-CoV-2 spike (“S2P”)	This paper	N/A
Recombinant SARS-CoV-2 RBD	This paper	N/A
TEV protease	This paper	N/A
BirA ligase	This paper	N/A
Streptavidin-PE	Invitrogen	Cat# S866
Ni Sepharose Excel	GE Healthcare	Cat# 17-3712-02
Human ACE2-Fc fusion protein	This study	N/A
MabSelect SuRE Resin	GE Healthcare	Cat# 97067-944
Kifunensine	Sigma-Aldrich	Cat# K1140
Peg/Ion Screen	Hampton	HR2-126
Peg/Ion 2 Screen	Hampton	HR2-098
Pierce Protein G Ultra Link Resin	Thermo Fisher Scientific	Cat# 53126
PEGRx 1 Screen	Hampton	HR2-082
PEGRx 2 Screen	Hampton	HR2-084
Critical commercial assays
SuperScriptTM III reverse transcriptase	Invitrogen	Cat# 18080044
Expifectamine 293 Transfection Kit	Thermo Fisher Scientific	Cat# A14525
Lipofectamine 3000	Thermo Fisher Scientific	Cat# L3000150
Deposited data
Crystal structure of C1A-B3/RBD complex	This paper	PDB: 7KFW
Crystal structure of C1A-F10/RBD complex	This paper	PDB: 7KFY
Crystal structure of C1A-C2/RBD complex	This paper	PDB: 7KFX
Crystal structure of C1A-B12/RBD complex	This paper	PDB: 7KFV
Experimental models: Cell lines
HEK293T cells	ATCC	CRL-11268; RRID:CVCL_1926
HEK293T-hACE2	Michael Farzan	N/A
HEKS293S Gnti−/− cells	ATCC	CRL-3022; RRID:CVCL_A785
Vero E6 C1008 cells	ATCC	ATCC CRL-1586; RRID:CVCL_0574
Expi293F cells	ThermoFisher	Cat#A14527; RRID: CVCL_D615
Expi293F SARS-CoV-2 S2P-His6	Bing Chen	N/A
Oligonucleotides
Primers for B cell receptor nested PCR and sequencing	Scheid et al., 2011	N/A
Recombinant DNA
SARS-CoV-2 S2P	This paper	N/A
CR3022 Fab	Galit Alter	GenBank: DQ168569.1 and DQ168570.1
4A8	Chi et al., 2020	Sequence from PDB: 7C2L
B38	Wu et al., 2020	Sequence from PDB: 7BZ5
CC12.1	(Yuan et al., 2020a)	Sequence from PDB: 6XC2
REGN10933	Hansen et al., 2020	Sequence from PDB: 6XDG
REGN10987	Hansen et al., 2020	Sequence from PDB: 6XDG
Human ACE2	Michael Farzan, Hyeryun Choe	N/A
Codon optimized SARS-CoV-2 S pCAGGS	This paper	N/A
Codon optimized SARS-CoV-2 S D614G pCAGGS	This paper	N/A
Codon optimized SARS-CoV-2 S D614G N439K pCAGGS	This paper	N/A
Codon optimized SARS-CoV-2 S D614G Q493K pCAGGS	This paper	N/A
Codon optimized SARS-CoV-2 S D614G Q493R pCAGGS	This paper	N/A
Codon optimized SARS-CoV-2 S day 146∗ pCAGGS	This paper	N/A
Codon optimized SARS-CoV-2 day 152 pCAGGS	This paper	N/A
VSV G pCAGGS	Radoshitzky et al., 2007	N/A
psPAX2	Didier Trono	Addgene Cat#63592
lentiCas9-EGFP	Chen et al., 2015	Addgene Cat#63592
Software and algorithms
IMGT/V-QUEST	http://www.imgt.org	N/A
ForteBio data analysis software	ForteBio	N/A
FlowJo version 10.6.2	FlowJo	https://www.flowjo.com; RRID:SCR_008520
XDS build 202 00131	Kabsch, 2010	https://xds.mr.mpg.de/;RRID:SCR_015652
AIMLESS v0.5.32	Evans and Murshudov, 2013	http://legacy.ccp4.ac.uk/html/aimless.html; RRID:SCR_015747
Phaser v2.8.3	McCoy et al., 2007	https://www.phenix-online.org/documentation/reference/phaser.html; RRID:SCR_014219
Phenix v1.18.2-3874	Adams et al., 2010	https://www.phenix-online.org; RRID: SCR_014224
Buster v2.10.3	Bricogne et al., 2017	https://www.globalphasing.com/buster/; RRID: SCR_015653
Prism v8.4.3	GraphPad Software	https://www.graphpad.com:443/; RRID: SCR_002798
O v15.0	Jones et al., 1991	N/A
Other
anti-CD20 MicroBeads	Miltenyi Biotec	Cat# 130-091-104
MACS LS column	Miltenyi Biotec	Cat# 130-042-401
anti-FLAG M2 Affinity Gel	Sigma-Aldrich	Cat# A2220; RRID: AB_10063035
Protein G UltraLink	Thermo Fisher Scientific	Cat#: 53125
MabSelect SuRE Resin	GE Healthcare	Cat# 17547401
Streptavidin biosensor	ForteBio	Cat# 18-5020
MoFlo Astrios EQ Cell Sorter	Beckman Coulter	N/A
iQue Screener PLUS	Intellicyt	N/A