LTB-specific IgG (A) and IgA (B) antibody titres in abomasum mucus following oral immunisation with four doses of control or LTB-transgenic plant materials.

<p>The horizontal lines represent geometric means. Black symbols denote positive responders defined as sheep with antibody titres at least three standard deviations above the control mean, non-responders are indicated by grey symbols.</p

LTB-specific IgG antibody titres in serum collected from sheep before immunisation with LTB-Leaf (A), LTB-HR (B) or control vaccines (C).

<p>Black symbols denote positive responders defined as sheep with antibody titres at least three standard deviations above the control mean, non-responders are indicated by grey symbols. The horizontal lines represent geometric means, statistical analysis (Student's t-test determined a significant difference between the means of the control and LTB-Leaf groups after four doses, p&lt;0.05).</p

Relative abundance of LTB-specific IgG (A) and IgA (B) at different sections of the sheep small intestine following oral immunisation with four doses of control or LTB-transgenic plant materials.

<p>The horizontal lines represent geometric means. Black symbols denote positive responders defined as sheep with antibody titres at least three standard deviations above the control mean, non-responders are indicated by grey symbols.</p

LTB-specific antibody titres detected in intestinal washes performed at four sites along the first 11

<p> <b>m of the sheep small intestine following oral immunisation with four doses of LTB-Leaf (A and D, IgG and IgA respectively), LTB-HR (B and E, IgG and IgA respectively) or control (C and F, IgG and IgA respectively).</b> Sections 1, 2, 3 and 4 are defined as the first 0–0.5 m, 3.5–4 m, 7–7.5 m and 10.5–11 m respectively from the abomasum/duodenum junction. Black symbols denote positive responders defined as sheep with antibody titres at least three standard deviations above the control mean, non-responders are indicated by grey symbols.</p

Oral immunisation treatments and number of sheep assigned to each group.

<p>Oral immunisation treatments and number of sheep assigned to each group.</p

Correlations between parasitological and immunological parameters in control and vaccinated sheep.

*<p>Spearman rank correlation coefficient (P value); bold numbers indicate significance at P&lt;0.05. ND: not done.</p

Packed cell volume (PCV) of peripheral blood after challenge of vaccinated sheep.

<p>Mean (+SEM) PCV of groups at 49 days post infection (DPI). The mean PCV of all sheep before infection (day 0) was 34.2 (SD 2.3). For details of experimental groups, refer to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078357#pone-0078357-t001" target="_blank">Table 1</a>.</p

Serum antibody responses after challenge of vaccinated sheep.

<p>Mean antibody isotype responses of sheep before vaccination (wk -8), 1 week after vaccination (wk -3), at day of challenge (wk 0) and 1 week after challenge (wk +1). Serum diluted 1/5000 (IgG1), 1/500 (IgG2), 1/20 (IgA) or 1/32 ammonium sulphate cut (IgE). For details of experimental groups, refer to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078357#pone-0078357-t001" target="_blank">Table 1</a>. Dashed line represents the mean of a separate group of 8 sheep kept in indoor pens for 2–3 months. *Significant difference between group 3 and control group 1.</p

Faecal egg counts and worm burden after challenge of vaccinated sheep.

<p>A: Mean (+SEM) daily eggs/gram faeces (EPG); B: Mean (+SEM) cumulative faecal egg count (FEC); C: individual and mean (+/−SEM) total worm counts. For details of experimental groups, refer to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078357#pone-0078357-t001" target="_blank">Table 1</a>. Significantly different from the control group at p&lt;0.05 (*) or p&lt;0.01 (**).</p

Sheep numbers, immunization protocols and levels of protection against <i>H.contortus</i> infection.

<p>ND: not done; *p&lt;0.05, **p&lt;0.001.</p