Journal of Immunology Research

Research Article

Immune Response and Partial Protection against Heterologous Foot-and-Mouth Disease Virus Induced by Dendrimer Peptides in Cattle

Table 2

Cellular immune response of cattle 32 days postvaccination analyzed by ³H-thymidine incorporation (a) and IFN-γ production (× 10² pg/ml) (b).

(a)


Group	Animal no.	SI (cpm Ag/cpm medium)
Group	Animal no.	Ag-B₂T	Ag-B₄T	Ag-T	iFMDV

B₂T	44	56.0	39.6	4.0	1.1
	170	3.0	5.2	1.0	1.2
	168	1.4	1.8	1.1	1.1
	169	2.0	1.9	0.9	1.5

B₄T	36	2.5	3.6	2.3	1.4
	431	3.5	1.6	1.0	1.2
	164	4.2	7.3	1.4	1.8
	166	4.0	5.7	0.8	1.3

Commercial vaccine	522	2.9	2.5	2.0	3.2
	800	1.4	2.0	1.2	1.6
	809	1.5	1.9	1.2	4.1
	810	1.2	1.4	0.9	0.9
	820	0.7	0.7	0.7	2.8

Negative	167	1.0	0.7	1.0	1.0
controls	997	1.0	1.4	0.9	0.9

(b)


Group	Animal no.	IFN-γ (× 10² pg/ml)
Group	Animal no.	Medium	Ag-B₂T	Ag-B₄T	Ag-T	iFMDV

B₂T	44	7.8	57.8	76.2	61.4	7.1
	170	14.0	32.1	30.2	12.4	11.3
	168	19.3	17.3	13.2	11.8	13.3
	169	12.3	14.0	14.6	15.0	17.9

B₄T	36	28.7	36.0	16.0	27.9	28.1
	431	32.8	15.7	54.0	34.0	35.0
	164	33.9	24.2	40.0	31.2	37.8
	166	7.9	6.0	6.5	6.8	6.8

Commercial vaccine	522	51.6	30.4	19.8	11.6	36.1
	800	7.4	7.6	7.4	7.1	7.5
	809	24.3	44.2	36.1	25.8	44.2
	810	16.9	14.3	13.7	18.0	15.9
	820	7.3	7.3	6.5	9.4	6.9

Negative controls	167	8.4	5.2	6.5	7.2	6.1
Negative controls	997	9.6	12.0	14.0	13.3	14.8

(a) Lymphoproliferation of PBMC from vaccinated cattle (32 dpv) determined by ³H-thymidine incorporation. Results were expressed as SI. PBMC were stimulated in vitro following incubation with dendrimeric peptides B₄T, B₂T or epitope T, iFMDV O1/Campos/Bra/58, or medium alone. Radioactivity was measured with b-scintillation counter. SI was calculated as cpm of each antigen specific proliferation Ag/cpm of cells basal proliferation. are considered positive. (b) IFN-γ production by PBMC after peptide stimulation as in (a). Supernatants were tested by ELISA, and the results, expressed in pg/ml, were calculated by interpolation in a cytokine standard curve. For each peptide, the cut-off was calculated as the mean IFN-γ production of PBMC from animals at day 0 plus 2 SD (≥15.0 × 10² pg/ml). Positive IFN-γ productions above cut-off are underlined.