Disassembly and reassembly of human papillomavirus virus-like particles produces more virion-like antibody reactivity

Table 1 Characteristics of the HPV 16 mAbs used in the epitope specific antigenicity analysis.

mAb (subclass)	Neutralizing activity	Type specificity	Epitope [critical amino acids] (Refs)	K_D(nM)^c	Application^d
Conformational epitopes
H16.V5 (G2b)	Strong (330)^b	Yes	FG loop, residues 266-297 (and HI loop, residues 339-365), [282, 50] [17, 18]	< 0.1	cLIA, IVRP, IC50 [19–22]
H16.E70 (G2b)	Strong (1)^b	Yes	Similar to V5, [285, 288, 266, 282] [23, 24]	0.15	IC50
H236.A2	Strong (11)^b	Yes	HI loop, residues 339-365 (and FG loop 266-297)	< 0.1	IC50
Linear epitopes ^e
H16.J4 (G2a)	Weak	No	261-280 [17, 25]	2-5	IVRP, IC50 [19, 20]
H16.O7	No	No	174-185	~2
H16.H5 (G2b)	No	No	174-185 [23]

H16.V5 was identified as the mAb with highest affinity and also with highest neutralization efficiency a
^a Due to the immunodominant nature of this epitope in the sera of naturally infected individuals [26] and its high affinity to VLPs, V5 is the detection Ab for the sandwich ELISA for product batch release and stability testing [19, 20]. In addition, it is also the mAb for the clinical serological assay with V5 as the marker in the competition RIA, ELISA or Luminex based assay for analyzing the sera from vaccines during clinical trials or post-licensure monitoring [21, 22]
^b Relative neutralization efficiency (value in parenthesis) for the mAb was normalized to E70 [27]
^c The K_D values are estimated with equilibrium based, indirect binding ELISA or SPR based methods with post-D/R VLPs [28, 29]
^d In support of Gardasil^® development and commercial manufacturing
^e Most linear epitopes are not type specific. The linear epitopes, such as that of J4, were identified with immunoreactivity of synthetic peptides to the sera of patients with HPV infection and cervical neoplasms [25, 30]

ISSN: 1743-422X