Phage displaying peptides mimic schistosoma antigenic epitopes selected by rat natural antibodies and protective immunity induced by their immunization in mice

Table 1 Killing effect of different sera on schistosomula in vitro.

Sera	Schistosomula (n)	Mortality (%)
		24 h	48 h	72 h
NRS	206	23.0	76.2	86.4
Heat-inactive normal	234	16.9	41.0	43.6
rat sera
NMS	240	6.4	23.8	30.0
RS	231	4.7	16.9	21.2

Table 2 Percentage enrichment of phages by biopanning.

Biopanning	Phages added	Phages washed	Yield (%)
1	1.5×1011	2.47×105	1.65×106
2	1.0×1011	4.26×106	4.26×105
3	1.0×1011	5.00×107	5.00×104

Table 3 DNA and AA sequences of the positive phage clones (P3, P5).

Clone	DNA sequence	AA sequence
P3	AAACGGAGGCTGCGGCCCAGT	K R R L R P S R V R I E
	AGAGTGAGAATAGAA
P5	AATATGCCTATTAGCATGAAG	N M P A S M K R V R I E
	AGAGTGAGAATAGAA

Table 4 Worm reduction in mice immunized with phage clones (mean±SD).

Groups	Mice (n)	Worms (n)	Worm reduction rates (%)	P
Mix phage (P3+P5) immunized	12	19.42±5.99	34.90	0.000a
P3 immunized	12	20.58±5.36	31.01	0.001a
P5 immunized	12	25.50±4.17	14.52	0.074
Original phage control	12	27.92±5.08	6.40	0.338
TBS control	12	29.83±2.92	–	–

^aP<0.05 vs TBS control group.

Table 5 Reduction in egg load in liver of mice immunized with phage clones (mean±SD).

Groups	Mice (n)	LEPG (×104)	LEPG reduction rate (%)	P
Mix phage (P3+P5) immunized	12	0.890±0.063	67.62	0.000a
P3 immunized	12	1.073±0.136	61.20	0.000a
P5 immunized	12	1.769±0.063	35.65	0.000a
Original phage control	12	2.255±0.142	17.97	0.013a
TBS control	12	2.749±0.144	–	–

^aP<0.05 vs TBS control group.