Survival rates of <i>Swiss</i> mice infected with 10⁴ tachyzoites from <i>T</i>. <i>gondii</i> isolates and treated during 10 days with different doses of sulfadiazine (80, 160, and 320 mg/Kg/day), initiating 48 hours after the inoculum.

<p>Isolates: TgCTBr03 (A), TgCTBr07 (B), TgCTBr08 (C), TgCTBr11 (D) and TgCTBr16. NTC Groups (E): non-treated control groups, infected with the respective isolate.</p

Bioassay of the surviving mice after infection with <i>T</i>. <i>gondii</i> isolates TgCTBr08, TgCTBr11, and TgCTBr16 and treatment with different doses of SDZ, for verification of cerebral parasitism.

<p>Bioassay of the surviving mice after infection with <i>T</i>. <i>gondii</i> isolates TgCTBr08, TgCTBr11, and TgCTBr16 and treatment with different doses of SDZ, for verification of cerebral parasitism.</p

<i>Toxoplasma gondii</i> isolates tested for susceptibility to Sulfadiazine and characteristics of the newborns from which the isolates were obtained.

<p><i>Toxoplasma gondii</i> isolates tested for susceptibility to Sulfadiazine and characteristics of the newborns from which the isolates were obtained.</p

Expression and purification of recombinant Cathepsin L-like protein.

<p>Protein samples were separated by 12.5% SDS-PAGE gel electrophoresis. (<b>A</b>) Molecular weight standard, (<b>B</b>) lysate of culture before and (<b>C</b>) after induction with IPTG and (<b>D</b>) recombinant Cathepsin L-like protein (MW 47.6 KDa) purified by gel filtration.</p

Diagnostic performance of <i>r</i>CatL, peptide-1, SLbA and the EIE-LVC kit using ROC curves. Data validation and agreement was confirmed using a kappa index.

a<p>The kappa index was calculated using all samples presented in this work for TL (CT + CD + CL + ML. n = 135), VL (CT + CD + VL. n = 125) and CVL (CT + CD + CVL. n = 75).</p>b<p>Agreement was calculated using parasitological assays as the gold standard.</p><p>*<i>Cut-off</i> obtained by ROC curve.</p>#<p><i>Cut-off</i> suggested by the manufacturer.</p><p>Abbreviations: AUC: area under curve; CI: confidence interval; TP: true positive; TN: true negative; FP: false positive; FN: false negative; κ: kappa index; NA: not applicable.</p><p>Diagnostic performance of <i>r</i>CatL, peptide-1, SLbA and the EIE-LVC kit using ROC curves. Data validation and agreement was confirmed using a kappa index.</p

Unveiling the Intracellular Survival Gene Kit of Trypanosomatid Parasites

<div><p>Trypanosomatids are unicellular protozoans of medical and economical relevance since they are the etiologic agents of infectious diseases in humans as well as livestock. Whereas <i>Trypanosoma cruzi</i> and different species of <i>Leishmania</i> are obligate intracellular parasites, <i>Trypanosoma brucei</i> and other trypanosomatids develop extracellularly throughout their entire life cycle. After their genomes have been sequenced, various comparative genomic studies aimed at identifying sequences involved with host cell invasion and intracellular survival have been described. However, for only a handful of genes, most of them present exclusively in the <i>T. cruzi</i> or <i>Leishmania</i> genomes, has there been any experimental evidence associating them with intracellular parasitism. With the increasing number of published complete genome sequences of members of the trypanosomatid family, including not only different <i>Trypanosoma</i> and <i>Leishmania</i> strains and subspecies but also trypanosomatids that do not infect humans or other mammals, we may now be able to contemplate a slightly better picture regarding the specific set of parasite factors that defines each organism's mode of living and the associated disease phenotypes. Here, we review the studies concerning <i>T. cruzi</i> and <i>Leishmania</i> genes that have been implicated with cell invasion and intracellular parasitism and also summarize the wealth of new information regarding the mode of living of intracellular parasites that is resulting from comparative genome studies that are based on increasingly larger trypanosomatid genome datasets.</p></div

Immunodepletion assay showing specific IgG antibody recognition of the synthetic peptides with known reactivity to Cathepsin L-like.

<p>Pools of sera (n = 10) from the different groups were depleted with peptide-1 (CT, control group; CD, Chagas disease; CL, cutaneous leishmaniasis; ML, mucosal leishmaniasis; VL, visceral leishmaniasis; CVL, canine visceral leishmaniasis). The mean antibody OD values are shown on the <i>y</i>-axis, and the error bars indicate the standard deviation. Significant differences are indicated on the graphs (*<i>p</i><0.05; **<i>p</i><0.01; ***<i>p</i><0.001).</p

Comparison of ROC curves obtained from <i>r</i>CatL, Peptide-1 and SLbA.

<p>The ROC curves were used to determine the ELISA cut-off, sensitivity, specificity and AUC. In case of SLbA for CVL diagnosis (EIE-LVC Kit), ROC curve is not shown (not applicable) in this graph because the cut-off was determined according to the recommendations by the manufacturer (twice the average of the negative control included in kit).</p

Diagnostic performance of <i>r</i>CatL, peptide-1, SLbA and the EIE-LVC kit.

a<p>Parameters was calculated using all samples presented in this work for TL (CT + CD + CL + ML. n = 135). VL (CT + CD + VL. n = 125) and CVL (CT + CD + CVL. n = 75).</p><p>*<i>Cut-off</i> obtained by ROC curve.</p>#<p><i>Cut off</i> obtained according to the manufacturer.</p><p>Abbreviations: Tse; total sensitivity; TSp: total specificity; CI: confidence interval; PPV: positive predictive value; NPV: negative predictive value; AC: accuracy.</p><p>Diagnostic performance of <i>r</i>CatL, peptide-1, SLbA and the EIE-LVC kit.</p

Comparison of the ELISA reactivity of <i>r</i>CatL, Peptide-1, SLbA and the EIE-LVC kit against sera from TL and VL patients and from <i>L. infantum</i>-infected dogs.

<p><b>TL and VL</b>: ELISAs were performed on samples from different groups of individuals (CT, control group; CD, Chagas disease patients; CL, cutaneous leishmaniasis; ML, mucosal leishmaniasis; VL, visceral leishmaniasis). <b>CVL</b>: ELISAs were performed on samples from different groups of dogs (CT, control group; CD, <i>T. cruzi</i>-infected dogs; CVL, canine visceral leishmaniasis). ^*Cut-off obtained by a ROC curve. ^#Cut-off suggested by the manufacturer.</p