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Mar Sileslucas - One of the best experts on this subject based on the ideXlab platform.

  • follow up of surgically treated patients with cystic echinococcosis can novel Recombinant antigens compete with imaging analysis of a patient cohort
    Tropical Medicine & International Health, 2017
    Co-Authors: Marija Stojkovic, Hansmicha Adt, Kerstin D Rosenberger, Ghalia Boubaker, Ana Hernandezgonzalez, Thomas Junghanss, Marcel Zwahlen, Mar Sileslucas
    Abstract:

    Objective To compare the performance of two novel Recombinant antigens (EgP29, 2B2t) with imaging in a well-defined cohort of surgically treated cystic echinococcosis (CE) patients to determine whether serology reflects surgical cure as defined by imaging. Methods From a cohort of 223 CE-confirmed patients of a national clinical center for echinococcosis, 36 surgically treated patients were eligible for analysis. Sera were tested by enzyme-linked immunosorbent assay (ELISA) for specific IgG and IgG4 antibodies against the EgP29 and 2B2t antigens. We used a hierarchical linear regression model to examine the course of antibody levels over time for each patient. A meta-analysis of the patient-specific estimates of the time to negativity was performed using the metan command in Stata. Results The range of positive serological results at the beginning of post-surgical monitoring was 34–60%: 2B2t 51%, 2B2t-IgG4 34%, EgP29 60%, EgP29-IgG4 40%. The pooled estimates of time to seronegativity were as follows: 2B2t-ELISA 3.92 (3.24, 4.61) years; 2B2t-IgG4-ELISA 4.60 (3.91, 5.29) years; EgP29-ELISA 3.94 (3.50, 4.39) years; EgP29-IgG4-ELISA 2.55 (1.93, 3.18) years. Conclusion After surgical treatment, antibodies to the Recombinant antigens 2B2t and EgP29 become negative in the majority of CE-confirmed, surgically cured patients. The major drawback is the fact that only around half of the CE-confirmed, surgically treated patients were at all responsive to the test antigens, so they are of limited benefit for documenting primary cure. Equally, these antigens do not appear to be sensitive to recurrences. This article is protected by copyright. All rights reserved.

  • improved serodiagnosis of cystic echinococcosis using the new Recombinant 2b2t antigen
    PLOS Neglected Tropical Diseases, 2012
    Co-Authors: Ana Hernandezgonzalez, Hector H Garcia, Guillermo Ramos, Antonio Orduna, Saul J Santivanez, Silvia Rodriguez, Santiago Munoz, Mar Sileslucas
    Abstract:

    A standardized test for the serodiagnosis of human cystic echinococcosis (CE) is still needed, because of the low specificity and sensitivity of the currently available commercial tools and the lack of proper evaluation of the existing Recombinant antigens. In a previous work, we defined the new ELISA-B2t diagnostic tool for the detection of specific IgGs in CE patients, which showed high sensitivity and specificity, and was useful in monitoring the clinical evolution of surgically treated CE patients. Nevertheless, this Recombinant antigen gave rise to false-negative results in a percentage of CE patients. Therefore, in an attempt to improve its sensitivity, we constructed B2t-derived Recombinant antigens with two, four and eight tandem repeat of B2t units, and tested them by ELISA on serum samples of CE patients and patients with related parasites. The best diagnostic values were obtained with the two tandem repeat 2B2t antigen. The influence of several clinical variables on the performance of the tests was also evaluated. Finally, the diagnostic performance of the 2B2t-ELISA was compared with that of an indirect haemagglutination commercial test. The 2B2t Recombinant antigen performed better than the HF and B2t antigens, and the IHA commercial kit. Therefore, this new 2B2t-ELISA is a promising candidate test for the serodiagnosis of CE in clinical settings.

  • subolesin akirin orthologs from ornithodoros spp soft ticks cloning rnai gene silencing and protective effect of the Recombinant proteins
    Veterinary Parasitology, 2012
    Co-Authors: Raul Manzanoroman, Ana Oleaga, Veronica Diazmartin, Mar Sileslucas, Ricardo Perezsanchez
    Abstract:

    Subolesin/akirin is a well characterized protective antigen highly conserved across vector species and thus potentially useful for the development of a broad-spectrum vaccine for the control of arthropod infestations including hard ticks, mosquitoes, sand flies and the poultry red mite Dermanyssus gallinae. Soft ticks could be also targeted by this vaccine if proved that the soft tick subolesin orthologs are conserved and induce protective immune responses too. However, to date no soft tick subolesin orthologs have been fully characterized nor tested as Recombinant antigens in vaccination trials. The objectives of the present work were to clone and characterize the subolesin orthologs from two important vector species of soft ticks as Ornithodoros erraticus and O. moubata, to evaluate the effect of subolesin gene silencing by RNAi, and to test the protective value of the Recombinant antigens in vaccination trials. The obtained results demonstrate that both soft tick subolesins are highly conserved showing more than 69% and 74% identity with those of hard ticks in their nucleotide and amino acid sequences, respectively. Additionally, we demonstrate that both soft ticks possess fully operative RNAi machinery, and that subolesin gene silencing by dsRNA injection inhibits oviposition indicating the involvement of subolesin in tick reproduction. Finally, vaccination with the Recombinant soft tick subolesins induced a partial protective effect resulting in the reduction of the oviposition rate. These preliminary results encourage further studies on the use of Recombinant subolesins as vaccines for the control of soft tick infestations, either alone or in combination with other specific molecules.

  • usefulness of four different echinococcus granulosus Recombinant antigens for serodiagnosis of unilocular hydatid disease uhd and postsurgical follow up of patients treated for uhd
    Clinical and Vaccine Immunology, 2008
    Co-Authors: Ana Hernandezgonzalez, Antonio Muro, Inmaculada Barrera, Guillermo Ramos, Antonio Orduna, Mar Sileslucas
    Abstract:

    Four different Recombinant antigens derived from Echinococcus granulosus, designated B1t, B2t, E14t, and C317, were tested with enzyme-linked immunosorbent assays (ELISAs) for the detection of specific immunoglobulin G (IgG) in patients with unilocular hydatid disease (UHD). The results were compared to those obtained with hydatid fluid and were subjected to receiver operator characteristic analysis. The diagnostic performance of the above-listed proteins was defined with respect to their specificity, sensitivity, and predictive values (PV); the influence of cyst location; and usefulness in the follow-up of surgical treatment for UHD and in the determination of whether or not patients have been surgically cured of UHD. The best diagnostic results were obtained with the anti-B2t IgG ELISA, with 91.2% sensitivity, 93% specificity, and high positive and negative PV (89.4 and 94.2, respectively). In addition, this diagnostic tool proved to be useful for the follow-up of surgically treated UHD patients. The anti-B2t IgG ELISA may find an application in the serodiagnosis of UHD in clinical laboratories.

José De La Fuente - One of the best experts on this subject based on the ideXlab platform.

  • A reverse vaccinology approach to the identification and characterization of Ctenocephalides felis candidate protective antigens for the control of cat flea infestations
    'Springer Science and Business Media LLC', 2019
    Co-Authors: Contreras Marinela, Villar Margarita, Artigas-jerónimo Sara, Kornieieva Lidiia, Mytrofanov Sergii, José De La Fuente
    Abstract:

    [Background]: Despite the abundance of the domestic cat flea, Ctenocephalides felis (Bouché, 1835) and disease risks associated with them, flea control is difficult and requires the development of new control interventions such as vaccines. In this study, a reverse vaccinology approach was designed to achieve a rational selection of cat flea candidate protective antigens. [Methods]: Based on transcriptomics and proteomics data from unfed adult fleas it was possible to select more specific candidate protective antigens based on highly represented and functionally relevant proteins present in the predicted exoproteome. The protective capacity of the Recombinant antigens was evaluated for the control of C. felis infestations in vaccinated cats. [Results]: Vaccination with Recombinant antigens induced an antibody response in immunized cats. Furthermore, a correlation was obtained between the effect of vaccination (antibody levels) and vaccine efficacy on flea phenotype (egg hatchability). The results suggested that the main effect of vaccination with these antigens was on reducing cat flea egg hatchability and fertility, with an overall vaccine efficacy of 32-46%. Although vaccination with these antigens did not have an effect on flea infestations, vaccines affecting reproductive capacity could reduce cat flea populations, particularly under conditions of direct insect transmission between cats. [Conclusions]: These results support the development of vaccines with protective antigens affecting flea reproduction and development after feeding on immunized animals for the control of cat flea infestations.This research was partially supported by CSIC grant 201440E098 to JF.Peer Reviewe

  • Control of infestations by Ixodes ricinus tick larvae in rabbits vaccinated with aquaporin Recombinant antigens
    'Elsevier BV', 2019
    Co-Authors: Contreras Marinela, José De La Fuente
    Abstract:

    [Background]: Tick-borne diseases greatly impact human and animal health worldwide, and vaccines are an environmentally friendly alternative to acaricides for their control. Recent results have suggested that aquaporin (AQP) water channels have a key function during tick feeding and development, and constitute good candidate antigens for the control of tick infestations. [Methods]: Here we describe the effect of vaccination with the Ixodes ricinus AQP1 (IrAQP) and a tick AQP conserved region (CoAQP) on I. ricinus tick larval mortality, feeding and molting. [Results]: We demonstrated that vaccination with IrAQP and CoAQP had an efficacy of 32% and 80%, respectively on the control of I. ricinus larvae by considering the cumulative effect on reducing tick survival and molting. [Conclusions]: The effect of the AQP vaccines on larval survival and molting is essential to reduce tick infestations, and extended previous results on the effect of R. microplus AQP1 on the control of cattle tick infestations. These results supports that AQP, and particularly CoAQP, might be a candidate protective antigen for the control of different tick species.This research was partially supported by CSIC grant 201440E098 to JF.Peer Reviewe

  • a reverse vaccinology approach to the identification and characterization of ctenocephalides felis candidate protective antigens for the control of cat flea infestations
    Parasites & Vectors, 2018
    Co-Authors: Marinela Contreras, Margarita Villar, Lidiia Kornieieva, Sergіі Mуtrofanov, José De La Fuente, Sara Artigasjeronimo
    Abstract:

    Despite the abundance of the domestic cat flea, Ctenocephalides felis (Bouche, 1835) and disease risks associated with them, flea control is difficult and requires the development of new control interventions such as vaccines. In this study, a reverse vaccinology approach was designed to achieve a rational selection of cat flea candidate protective antigens. Based on transcriptomics and proteomics data from unfed adult fleas it was possible to select more specific candidate protective antigens based on highly represented and functionally relevant proteins present in the predicted exoproteome. The protective capacity of the Recombinant antigens was evaluated for the control of C. felis infestations in vaccinated cats. Vaccination with Recombinant antigens induced an antibody response in immunized cats. Furthermore, a correlation was obtained between the effect of vaccination (antibody levels) and vaccine efficacy on flea phenotype (egg hatchability). The results suggested that the main effect of vaccination with these antigens was on reducing cat flea egg hatchability and fertility, with an overall vaccine efficacy of 32–46%. Although vaccination with these antigens did not have an effect on flea infestations, vaccines affecting reproductive capacity could reduce cat flea populations, particularly under conditions of direct insect transmission between cats. These results support the development of vaccines with protective antigens affecting flea reproduction and development after feeding on immunized animals for the control of cat flea infestations.

  • A reverse vaccinology approach to the identification and characterization of Ctenocephalides felis candidate protective antigens for the control of cat flea infestations
    BMC, 2018
    Co-Authors: Marinela Contreras, Margarita Villar, Sara Artigas-jerónimo, Lidiia Kornieieva, Sergіі Mуtrofanov, José De La Fuente
    Abstract:

    Abstract Background Despite the abundance of the domestic cat flea, Ctenocephalides felis (Bouché, 1835) and disease risks associated with them, flea control is difficult and requires the development of new control interventions such as vaccines. In this study, a reverse vaccinology approach was designed to achieve a rational selection of cat flea candidate protective antigens. Methods Based on transcriptomics and proteomics data from unfed adult fleas it was possible to select more specific candidate protective antigens based on highly represented and functionally relevant proteins present in the predicted exoproteome. The protective capacity of the Recombinant antigens was evaluated for the control of C. felis infestations in vaccinated cats. Results Vaccination with Recombinant antigens induced an antibody response in immunized cats. Furthermore, a correlation was obtained between the effect of vaccination (antibody levels) and vaccine efficacy on flea phenotype (egg hatchability). The results suggested that the main effect of vaccination with these antigens was on reducing cat flea egg hatchability and fertility, with an overall vaccine efficacy of 32–46%. Although vaccination with these antigens did not have an effect on flea infestations, vaccines affecting reproductive capacity could reduce cat flea populations, particularly under conditions of direct insect transmission between cats. Conclusions These results support the development of vaccines with protective antigens affecting flea reproduction and development after feeding on immunized animals for the control of cat flea infestations

  • control of infestations by ixodes ricinus tick larvae in rabbits vaccinated with aquaporin Recombinant antigens
    Vaccine, 2017
    Co-Authors: Marinela Contreras, José De La Fuente
    Abstract:

    Abstract Background Tick-borne diseases greatly impact human and animal health worldwide, and vaccines are an environmentally friendly alternative to acaricides for their control. Recent results have suggested that aquaporin (AQP) water channels have a key function during tick feeding and development, and constitute good candidate antigens for the control of tick infestations. Methods Here we describe the effect of vaccination with the Ixodes ricinus AQP1 (IrAQP) and a tick AQP conserved region (CoAQP) on I. ricinus tick larval mortality, feeding and molting. Results We demonstrated that vaccination with IrAQP and CoAQP had an efficacy of 32% and 80%, respectively on the control of I. ricinus larvae by considering the cumulative effect on reducing tick survival and molting. Conclusions The effect of the AQP vaccines on larval survival and molting is essential to reduce tick infestations, and extended previous results on the effect of R. microplus AQP1 on the control of cattle tick infestations. These results supports that AQP, and particularly CoAQP, might be a candidate protective antigen for the control of different tick species.

Nicola Gargano - One of the best experts on this subject based on the ideXlab platform.

  • use of Recombinant antigens for early postnatal diagnosis of congenital toxoplasmosis
    Journal of Clinical Microbiology, 2005
    Co-Authors: Wilma Buffolano, Mariassunta Del Pezzo, Manlio Di Cristina, Elisa Beghetto, Andrea Spadoni, Eskild Petersen, Nicola Gargano
    Abstract:

    The main objective of this work was to improve the early serologic diagnosis of toxoplasmosis in children at risk of congenital infection by using Recombinant antigens. Serum samples from 104 infants born to mothers with primary Toxoplasma gondii infection acquired during pregnancy, of which 35 were congenitally infected and 22 had clinical silent toxoplasmosis at birth, were included. Immunoglobulin M (IgM), IgG, and IgG subtype antibodies against epitopes carried by fragments of T. gondii MIC2, MIC3, MIC4, M2AP, AMA1, and SAG1 gene products were measured by performing parallel enzyme immunoassays (Rec-ELISAs). Recombinant antigens preferentially reacted with IgG antibodies from infected infants compared to uninfected subjects (P < 0.0001), indicating that sera from infected children recognized a more diverse repertoire of antigens than sera transferred over the placenta from the mothers. Using two serial samples collected within 3 months of life, it was possible to demonstrate a neosynthesis of specific anti-MIC2 and anti-SAG1 immunoglobulin G, mainly of the IgG2 subtype, in 13 out of 20 infants with congenital toxoplasmosis. IgM antibodies in 97% of infected infants reacted with at least one of the Recombinant antigens, confirming the diagnosis of congenital infection as soon as 2 months after birth (P < 0.0001). The use of Recombinant antigens is effective in distinguishing T. gondii-infected from uninfected infants and shows that assays based on Recombinant antigens improve the diagnosis of newborns with congenital toxoplasmosis.

  • Use of an Immunoglobulin G Avidity Assay Based on Recombinant antigens for Diagnosis of Primary Toxoplasma gondii Infection during Pregnancy
    Journal of Clinical Microbiology, 2003
    Co-Authors: Elisa Beghetto, Mariassunta Del Pezzo, Olga Minenkova, Manlio Di Cristina, Andrea Spadoni, Wilma Buffolano, Franco Felici, Eskild Petersen, Nicola Gargano
    Abstract:

    The objective of this work was to develop an antibody-specific immunoglobulin G (IgG) avidity assay to discriminate between acute and latent phases of Toxoplasma gondii infection by using Recombinant antigens. One hundred twenty-one serum samples from women who developed IgG antibodies against Toxoplasma during pregnancy were used. The IgG avidities of antibodies directed against epitopes carried by fragments of GRA3, GRA7, MIC3, and SAG1 antigens were measured by performing parallel enzyme immunoassays. The avidity index for Toxoplasma-specific antibodies against a homogeneous mixture of Recombinant GRA3, GRA7, MIC3, and SAG1 antigens correlated closely with the IgG avidity of antibodies against lysed whole-cell T. gondii antigen. The avidity assay performed with the Recombinant MIC3 antigen highlighted the presence of avidity low-antibodies IgG exclusively in sera collected within 2 months after primary infection. The presence of T. gondii-specific, low-avidity IgG antibodies against Recombinant MIC3 antigen can be used to determine the point of infection with T. gondii within a 2-month time frame after infection.

Lorenzo Giacani - One of the best experts on this subject based on the ideXlab platform.

  • p165 evaluation of novel treponema pallidum Recombinant antigens for syphilis diagnosis
    Sexually Transmitted Infections, 2021
    Co-Authors: Emily Romeis, Austin M Haynes, A Phan, Kelika A Konda, Silver K Vargas, Maria Eguiluz, Carlos F Caceres, Jeffrey D Klausner, Lorenzo Giacani
    Abstract:

    Background Syphilis, caused by the spirochete Treponema pallidum subsp. pallidum (T. pallidum), continues to be a significant global health concern. The diagnosis of syphilis mainly relies on assessing clinical manifestations and performing serologic testing to detect treponemal and non-treponemal antibodies to discriminate between past and present infection and to evaluate response to treatment. Limitations, however, include that no test can discriminate among syphilis stages, and sensitivity is low during the very early stages of infection. New diagnostics could circumvent some of these deficiencies. Methods To this end, we developed a novel array of T. pallidum Recombinant proteins to identify seroreactive proteins and compare their performance to that of antigens commonly used in treponemal tests such as the 17 and 47 kDa lipoproteins (Tp0435 and Tp0574, respectively). antigens were applied to the array, then reactivity was assessed via indirect enzyme-linked immunosorbent assay (ELISA). For this analysis, we used sera samples from 124 patients collected at various timepoints (0 months, 3 months, and 6 months). Samples from all three timepoints were available from 29 patients. Results The control antigens demonstrated the highest reactivity against the sera. Among the antigens tested so far Tp0954, a putative adhesin of the syphilis agent, exhibited seroreactivity similar to that of the controls. Conclusion Our data support Tp0954 as a possible candidate to improve the performance of currently available treponemal tests.

Kelika A Konda - One of the best experts on this subject based on the ideXlab platform.

  • p165 evaluation of novel treponema pallidum Recombinant antigens for syphilis diagnosis
    Sexually Transmitted Infections, 2021
    Co-Authors: Emily Romeis, Austin M Haynes, A Phan, Kelika A Konda, Silver K Vargas, Maria Eguiluz, Carlos F Caceres, Jeffrey D Klausner, Lorenzo Giacani
    Abstract:

    Background Syphilis, caused by the spirochete Treponema pallidum subsp. pallidum (T. pallidum), continues to be a significant global health concern. The diagnosis of syphilis mainly relies on assessing clinical manifestations and performing serologic testing to detect treponemal and non-treponemal antibodies to discriminate between past and present infection and to evaluate response to treatment. Limitations, however, include that no test can discriminate among syphilis stages, and sensitivity is low during the very early stages of infection. New diagnostics could circumvent some of these deficiencies. Methods To this end, we developed a novel array of T. pallidum Recombinant proteins to identify seroreactive proteins and compare their performance to that of antigens commonly used in treponemal tests such as the 17 and 47 kDa lipoproteins (Tp0435 and Tp0574, respectively). antigens were applied to the array, then reactivity was assessed via indirect enzyme-linked immunosorbent assay (ELISA). For this analysis, we used sera samples from 124 patients collected at various timepoints (0 months, 3 months, and 6 months). Samples from all three timepoints were available from 29 patients. Results The control antigens demonstrated the highest reactivity against the sera. Among the antigens tested so far Tp0954, a putative adhesin of the syphilis agent, exhibited seroreactivity similar to that of the controls. Conclusion Our data support Tp0954 as a possible candidate to improve the performance of currently available treponemal tests.