Limits...
Immunodiagnosis of canine visceral leishmaniasis using mimotope peptides selected from phage displayed combinatorial libraries.

Toledo-Machado CM, de Avila RA, NGuyen C, Granier C, Bueno LL, Carneiro CM, Menezes-Souza D, Carneiro RA, Chávez-Olórtegui C, Fujiwara RT - Biomed Res Int (2015)

Bottom Line: Peptides were synthesized, polymerized with glutaraldehyde, and used as antigens in ELISA assays.Each individual peptide or a mix of them was reactive with infected dogs serum.The assay was highly sensitive and specific when compared to soluble Leishmania antigen that showed cross-reactivity with anti-T. cruzi IgGs.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Parasitologia, ICB, Universidade Federal de Minas Gerais, CP 486, Belo Horizonte 31270-901, MG, Brazil.

ABSTRACT
ELISA and RIFI are currently used for serodiagnosis of canine visceral leishmaniasis (CVL). The accuracy of these tests is controversial in endemic areas where canine infections by Trypanosoma cruzi may occur. We evaluated the usefulness of synthetic peptides that were selected through phage display technique in the serodiagnosis of CVL. Peptides were chosen based on their ability to bind to IgGs purified from infected dogs pooled sera. We selected three phage clones that reacted only with those IgGs. Peptides were synthesized, polymerized with glutaraldehyde, and used as antigens in ELISA assays. Each individual peptide or a mix of them was reactive with infected dogs serum. The assay was highly sensitive and specific when compared to soluble Leishmania antigen that showed cross-reactivity with anti-T. cruzi IgGs. Our results demonstrate that phage display technique is useful for selection of peptides that may represent valuable synthetic antigens for an improved serodiagnosis of CVL.

Show MeSH

Related in: MedlinePlus

ROC curves obtained from all tests. The curves were used to determine ELISA cut-off, sensitivity, specificity, and AUC.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4325972&req=5

fig4: ROC curves obtained from all tests. The curves were used to determine ELISA cut-off, sensitivity, specificity, and AUC.

Mentions: The area under the curve (AUC) and accuracy (AC) were used to compare the efficiency of different diagnostic tests [31]. Peptides 5 and 11 presented the highest AUC value (1.0000) and accuracy (AC = 1.0000), followed by peptide 6 (AUC = 0.9980 and AC = 0.9780) and pool (AUC = 0.9958 and AC = 0.9780) (Figure 4 and Table 1). The L. infantum chagasi antigen and EIE-LVC kit showed a lower accuracy value (0.8352 and 0.8791, resp.). The agreement between the serological tests using the Kappa Index is shown in Table 2. All peptides showed moderate agreement with EIE-LVC∗ and good agreement with crude leishmanial antigen.


Immunodiagnosis of canine visceral leishmaniasis using mimotope peptides selected from phage displayed combinatorial libraries.

Toledo-Machado CM, de Avila RA, NGuyen C, Granier C, Bueno LL, Carneiro CM, Menezes-Souza D, Carneiro RA, Chávez-Olórtegui C, Fujiwara RT - Biomed Res Int (2015)

ROC curves obtained from all tests. The curves were used to determine ELISA cut-off, sensitivity, specificity, and AUC.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4325972&req=5

fig4: ROC curves obtained from all tests. The curves were used to determine ELISA cut-off, sensitivity, specificity, and AUC.
Mentions: The area under the curve (AUC) and accuracy (AC) were used to compare the efficiency of different diagnostic tests [31]. Peptides 5 and 11 presented the highest AUC value (1.0000) and accuracy (AC = 1.0000), followed by peptide 6 (AUC = 0.9980 and AC = 0.9780) and pool (AUC = 0.9958 and AC = 0.9780) (Figure 4 and Table 1). The L. infantum chagasi antigen and EIE-LVC kit showed a lower accuracy value (0.8352 and 0.8791, resp.). The agreement between the serological tests using the Kappa Index is shown in Table 2. All peptides showed moderate agreement with EIE-LVC∗ and good agreement with crude leishmanial antigen.

Bottom Line: Peptides were synthesized, polymerized with glutaraldehyde, and used as antigens in ELISA assays.Each individual peptide or a mix of them was reactive with infected dogs serum.The assay was highly sensitive and specific when compared to soluble Leishmania antigen that showed cross-reactivity with anti-T. cruzi IgGs.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Parasitologia, ICB, Universidade Federal de Minas Gerais, CP 486, Belo Horizonte 31270-901, MG, Brazil.

ABSTRACT
ELISA and RIFI are currently used for serodiagnosis of canine visceral leishmaniasis (CVL). The accuracy of these tests is controversial in endemic areas where canine infections by Trypanosoma cruzi may occur. We evaluated the usefulness of synthetic peptides that were selected through phage display technique in the serodiagnosis of CVL. Peptides were chosen based on their ability to bind to IgGs purified from infected dogs pooled sera. We selected three phage clones that reacted only with those IgGs. Peptides were synthesized, polymerized with glutaraldehyde, and used as antigens in ELISA assays. Each individual peptide or a mix of them was reactive with infected dogs serum. The assay was highly sensitive and specific when compared to soluble Leishmania antigen that showed cross-reactivity with anti-T. cruzi IgGs. Our results demonstrate that phage display technique is useful for selection of peptides that may represent valuable synthetic antigens for an improved serodiagnosis of CVL.

Show MeSH
Related in: MedlinePlus