Characterization of S3Pvac Anti-Cysticercosis Vaccine Components: Implications for the Development of an Anti-Cestodiasis Vaccine

Background: Cysticercosis and hydatidosis seriously affect human health and are responsible for considerable economic loss in animal husbandry in non-developed and developed countries. S3Pvac and EG95 are the only field trial-tested vaccine candidates against cysticercosis and hydatidosis, respectively. S3Pvac is composed of three peptides (KETc1, GK1 and KETc12), originally identified in a Taenia crassiceps cDNA library. S3Pvac synthetically and recombinantly expressed is effective against experimentally and naturally acquired cysticercosis.Methodology/ Principal Findings: In this study, the homologous sequences of two of the S3Pvac peptides, GK1 and KETc1, were identified and further characterized in Taenia crassiceps WFU, Taenia solium, Taenia saginata, Echinococcus granulosus and Echinococcus multilocularis. Comparisons of the nucleotide and amino acid sequences coding for KETc1 and GK1 revealed significant homologies in these species. The predicted secondary structure of GK1 is almost identical between the species, while some differences were observed in the C terminal region of KETc1 according to 3D modeling. A KETc1 variant with a deletion of three C-terminal amino acids protected to the same extent against experimental murine cysticercosis as the entire peptide. on the contrary, immunization with the truncated GK1 failed to induce protection. Immunolocalization studies revealed the non stage-specificity of the two S3Pvac epitopes and their persistence in the larval tegument of all species and in Taenia adult tapeworms.Conclusions/ Significance: These results indicate that GK1 and KETc1 may be considered candidates to be included in the formulation of a multivalent and multistage vaccine against these cestodiases because of their enhancing effects on other available vaccine candidates

The combined treatment did not recover the ambulatory activity and rearing in the open field.

<p>The lesion reduced the ambulatory activity evaluated by the distance traveled (A) and frequency of rearing (B) during the first ten min in the open field. However, it did not produce bradykinesia assessed by the speed of walking (C). None of the treatments recovered the ambulatory activity or rearing (A and B). Intact rats did not showed changes either in ambulation or in rearing, throughout the experiment. The 6-OHDA lesion reduced significantly the traveled distance and frequency of rearing (A: F_{3, 6} = 73.75, <i>P</i> < 0.0001 and B: F_{3, 6} = 57.30, <i>P</i> < 0.0001, One-way repeated-measures ANOVA) but it did not produce a significant effect on bradykinesia (C: F_{3, 6} = 3.563, <i>P</i> < 0.0868, One-way repeated-measures ANOVA). *** <i>P</i> < 0.001 compared with saline-treated rats. ^# <i>P</i> = No significant difference compared with saline-treated rats (Bonferroni’s Multiple Comparison Post tests). The data are given as the mean ± SEM (<i>n</i> = 5–6 rats per group).</p

Illustration of the experimental design.

<p>Arrows with asterisk indicate an evaluation of the motor behavior, which included gait analysis, rotarod performance and ambulatory activity in the open field. Double asterisks indicate EMG recordings. Rats were 12 months old at the beginning of the experiment.</p

The combined treatment recovered normal muscle tone.

<p>The lesion increased the EMG activity of the contralateral gastrocnemius but did not affect the EMG of the ipsilateral one (A). The combined treatment normalized the EMG activity (A and B) and the effect persisted two months after the treatment (B). The D3 agonist also reduced the EMG, but the reduction was partial and occurred two months after the treatment (B). The recovery produced by the combined treatment was significant (F_{2, 6} = 5.674, <i>P</i> < 0.0414, One-way repeated-measures ANOVA). * <i>P</i> < 0.05; ** <i>P</i> < 0.01 compared with saline-treated rats (Bonferroni’s Multiple Comparison Post tests). The data are given as the mean ± SEM (<i>n</i> = 5 rats per group). A, shows a representative case.</p

Administration of the D3 agonist associated with the BDNF transfection restored motor coordination.

<p>The lesion reduced the time on the rod (A-I) and the rotarod performance (B). The combined treatment normalized the time on the rod (A-II) and the rotarod performance (B). The effect persisted two months after the treatment (A-III and B). The D3 agonist alone also recovered the motor coordination (A, B) but the rats dragged the contralateral hind limb during rod rotation (arrows in C and supplementary videos <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0117391#pone.0117391.s003" target="_blank">S3 Video</a>—ROTAROD PERFORMANCE IN NORMAL SPEED and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0117391#pone.0117391.s004" target="_blank">S4 Video</a>- ROTAROD PERFORMANCE IN SLOW MOTION). Saline-treated rats did not recover the rotarod performance (A, B). The recovery produced by the treatments were significant (AI: F_{3, 12} = 9.881, <i>P</i> < 0.0015; AII: F_{3, 12} = 8.879, <i>P</i> < 0.0023; AIII: F_{3, 12} = 12.49, <i>P</i> < 0.0005 and B: F_{3, 15} = 21.84, <i>P</i> < 0.0001, One-way repeated-measures ANOVA). * <i>P</i> < 0.05; ** <i>P</i> < 0.01; *** <i>P</i> < 0.001 compared with saline-treated rats. ^# <i>P</i> = No significant difference compared with intact rats (Bonferroni’s Multiple Comparison Post tests). The data are given as the mean ± SEM (<i>n</i> = 5–6 rats per group). C illustrates representative cases.</p

The combined treatment recovered the nigro-striatal innervation.

<p>(A) Representative micrographs of the substantia nigra pars compacta showing TH+ neurons with the presence of rhodamine-labeled dextran amine (arrowheads), previously injected into the striatum. (B) Graph showing the percentage of rhodamine-labeled TH+ neurons with respect to the total of TH+ neurons of the same substantia nigra pars compacta, in each experimental condition. The recovery produced by the treatments was significant (F_{2, 8} = 18.34, <i>P</i> < 0.0010, One-way ANOVA). * <i>P</i> < 0.05; ** <i>P</i> < 0.01 compared with saline-treated rats (Bonferroni’s Multiple Comparison Post tests). The data are given as the mean ± SEM (<i>n</i> = 4 rats per group).</p

Control de la calidad del diagnóstico coproparasitológico en la provincia de Ciudad de La Habana, Cuba External quality assessment in coproparasitology in Havana City Province, Cuba

Se realizó un estudio sobre la calidad del diagnóstico coproparasitológico en 77 laboratorios de la red de salud pública de la provincia Ciudad de La Habana, Cuba. El procedimiento se basó en la entrega a cada jefe de laboratorio de un modelo de encuesta, y una bolsa de nylon conteniendo 10 viales plásticos con distintos especímenes parasitarios, preservados en formaldehído al 7%. Recogidos los resultados en las primeras 72 horas después de su entrega, se realizó la evaluación mediante una escala de puntuación establecida. La mayoría de los laboratorios aprobaron (70%); sin embargo aún existen centros, sobre todo policlínicas, con calificaciones deficientes. Los municipios con resultados más desfavorables fueron, Lisa, Marianao y Habana del Este, alcanzándose mejores resultados en los hospitales que en las policlínicas. En el análisis de Protozooarios, el mejor diagnosticado fué Giardia lamblia, con solo un centro que erró al identificarlo. Las mayores dificultades se presentaron en Blastocystis hominis con 61% de fallas, Endolimax nana, con 24,6%, y Entamoeba histolytica, con 22%. Entre los helmintos, la mayor aprobación fué en Trichuris trichiura y los errores diagnósticos predominaron con Fasciola hepatica y Taenia sp., ambos con 66,2% de fallas. Dados los resultados obtenidos, hemos organizado una intervención educativa en la red de laboratorios de la provincia.<br>An external quality assessment in coproparasitology was carried out in 77 laboratories from Havana City. A questionnaire and ten plastic vials with different intestinal parasites in a small nylon bag, duly sealed, were sent to each laboratory. Answers were collected during the 72 hours after delivery. Results were analyzed by means of a computer program. The majority of the laboratories (70%) passed the test; the municipalities with the worst scores in the province were Lisa, Marianao, and Habana del Este. Better results were obtained among technologists working only in parasitology than those who were also performing other laboratory work, and better averages were observed in hospitals than in polyclinics. The best identified intestinal protozoan was Giardia lamblia and the worst identified was Blastocystis hominis (with a 61% mistake rate), followed by Endolimax nana (24.6%), and Entamoeba histolytica (22%). Among helminths, the best identified was Trichuris trichiura (9.2% mistake rate) and the highest percentage of incorrect diagnoses was for Taenia sp. and Fasciola hepatica (both with 66.2%). Taking into account these results, we feel it is necessary to provide training in parasitology among these laboratories