Table 1.

Biotinylated rgp41 peptides used for ELISA epitope mapping.

Antigen	Peptide	Epitope name	Length (aa)	Biotinylated gp41 peptide
gp41	S1	N-terminal	13	Biotin-MQARQLLSGIVQQ
	S2	Bacterial mimotope	13	Biotin-QQNNLLRAIEAQQ
	S3	HEPS	18	Biotin-GIKQLQARILAVERYLKD
	S4	Caveolin	18	SLEQIWNHTTWMEWDREI-K-Biotin
	S5	Transcytosis	16	EINNYTSLIHSLIEES-K-Biotin
gp41/P1	S6	5F3	15	SQTQQEKNEQELLEL-K-Biotin
P1	S7	2F5	17	Biotin-NEQELLELDKWASLWNW
P1	S8	4E10/10E8	17	Biotin-LWNWFNITNWLWYIKLS

These peptides are captured in streptavidin coated ELISA plates and used for evaluating the gp41 epitope reactivity profile of vaccine-induced serum antibodies in rat. Peptides have 13–18 amino acids (a.a.) in length and were derived from various gp41 regions of the HIV-1 HXB2 clade B strain, starting from the amino-terminus to the carboxyl-terminal end. Peptides S1 and S2 were designed for monitoring the level of vaccine-induced serum reactivity toward the gp41 N-terminal region and the bacterial mimotope present on the gp41. For peptides S3–S8, the sequences are based on reported gp41 epitopes toward which antibodies may harbor antiviral activities (caveolin, transcytosis), a region recognized by neutralizing antibodies present in HEPS or by the 2F5 and 4E10/10E8 neutralizing monoclonal antibodies (mAb) harboring cross-strain and cross-clade activities, and the non-neutralizing epitope recognized by the 5F3 monoclonal antibody.