Table 3. Biophysical properties of anti-TcdB V_HH-Fc fusions.

VHH-Fc/mAb	Hinge	Yield (mg/ 100 mL)a	Ve (mL)b	kd (s-1)	Maximum TcdB neutralization (%)c,d
B39-hFc	human	5.7	17.64	4.5 × 10−5	0.0
B69-hFc	human	13	14.24	2.0 × 10−4	18.0 ± 10.2
B71-hFc	human	6	13.91	4.7 × 10−5	11.0 ± 7.0
B74-hFc	human	4.4	13.82	1.3 × 10−4	26.3 ± 4.5
B94-hFc	human	12.2	13.52	2.0 × 10−5	55.9 ± 22.4
B131-hFc	human	14.6	13.70	9.6 × 10−5	18.0 ± 13.4
B167-hFc	human	2.5	13.85	8.1 × 10−5	37.5 ± 2.7
B39-cFc	camelid	7.9	15.07	2.0 × 10−5	0.1 ± 0.1
B69-cFc	camelid	9.1	13.13	2.0 × 10−4	20.2 ± 5.7
B71-cFc	camelid	11.3	12.98	4.7 × 10−5	8.9 ± 5.5
B74-cFc	camelid	6.8	12.95	9.4 × 10−5	22.3 ± 4.2
B94-cFc	camelid	11.8	12.84	2.4 × 10−5	61.2 ± 1.3
B131-cFc	camelid	21.6	12.84	9.6 × 10−5	18.7 ± 12.3
B167-cFc	camelid	9.2	12.90	8.1 × 10−5	22.8 ± 2.9
MDX-1388	human	-	n.d.	n.d.	70.7 ± 13.9

^aPurification yield from 100 mL HEK293 culture

^bV_e from Superdex 200

^c(mean ± SD)

^d250 nM antibody + 500 fM TcdB vero cell cytotoxicity (72 h); n.d., not determined.