Table 1. Summary of Anti-Idiotypic Monobody Selections on Monoclonal Antibodies.

All enrichments were performed for 3 rounds on the indicated target MAb (coated at 50 µg/mL in microtiter plate wells) except for the 447-52D enrichment, which was stopped after 2 rounds when high level enrichment was already evident.

Target mAb	Library1	Rounds	ELISA positive	Number Unique Sequences
b12	NHK, Tri	3	20/23	11
4E10	Tri	3	33/34	9
1F1	Comb NHK + Tri	3	6/6	3
2F5	Comb NHK + Tri	4	8/24	2
Z13e1	Tri	3	12/15	9
447-52D	NHK-HP, Tri	2	16/16	16
VRC-01	Comb NHK	3	8/16	7
Rituxan	Tri	3	18/20	7

¹The libraries used were either the NHK: produced by infection with VCS helper; Tri: trimer library produced by infection with VCS helper; Comb NHK+Tri: an equal volume mixture of the two VCS-produced libraries; NHK-HP +Tri: the NHK library was infected with helper phage and combined with an equal volume of the trimer library. Individual binding clones after 2 or 3 rounds of enrichment were identified by phage ELISA and the αIM inserts were amplified by colony PCR and sequenced.