Evaluation of Toxocara canis Glycosylated TES Produced in Pichia pastoris for Immunodiagnosis of Human Toxocariasis

Abstract Recombinant proteins are a suggested alternative for the diagnosis of toxocariasis. The current Escherichia coli recombinant protein overexpression system usually produces insoluble products. As an alternative, yeast such as Pichia pastoris have secretory mechanisms, which could diminish the cost and time for production. This study aimed to produce recombinant proteins in Pichia pastoris and verify their sensibility and specificity in an indirect ELISA assay. Two sequences (rTES-30 and rTES-120) of Toxocara canis excretory-secretory antigens were cloned in a pPICZαB vector and expressed in P. pastoris KM71H. Sera samples collected from human adults infected by Toxocara spp. were tested by indirect ELISA using rTES-30 and rTES-120 as antigens. Recombinant proteins were detected at 72 hours after induction, in the supernatant, as pure bands between 60~70 kDa with hyperglycosylation. Regarding diagnosis potential, recombinant antigens had high specificity (95.6%); however, sensitivity was 55.6% for rTES-30 and 68.9% for rTES-120. Further deglycosylation of the P. pastoris antigens did not seem to affect ELISA performance (p>0.05). The low sensitivity in the serodiagnosis diminished any advantage that P. pastoris expression could have. Therefore, we do not recommend P. pastoris recombinant TES production as an alternative for the diagnosis of toxocariasis.

Evaluation of three recombinant proteins for the development of ELISA and immunochromatographic tests for visceral leishmaniasis serodiagnosis.

BACKGROUND: Visceral Leishmaniasis (VL) is an infectious disease that is a significant cause of death among infants aged under 1 year and the elderly in Brazil. Serodiagnosis is a mainstay of VL elimination programs; however, it has significant limitations due to low accuracy. OBJECTIVE: This study aimed to evaluate three recombinant Leishmania infantum proteins (rFc, rC9, and rA2) selected from previous proteomics and genomics analyses to develop enzyme-linked immunosorbent assay (ELISA) and immunochromatographic tests (ICT) for the serodiagnosis of human VL (HVL) and canine VL (CVL). METHODS: A total of 186 human (70 L. infantum-infected symptomatic, 20 other disease-infected, and 96 healthy) and 185 canine (82 L. infantum-infected symptomatic, 27 L. infantum-infected asymptomatic, and 76 healthy) sera samples were used for antibody detection. FINDINGS: Of the three proteins, rA2 (91.5% sensitivity and 87% specificity) and rC9 (95.7% sensitivity and 87.5% specificity) displayed the best performance in ELISA-HVL and ELISA-CVL, respectively. ICT-rA2 also displayed the best performance for HVL diagnosis (92.3% sensitivity and 88.0% specificity) and had high concordance with immunofluorescence antibody tests (IFAT), ELISA-rK39, IT-LEISH®, and ELISAEXT. ICT-rFc, ICT-rC9, and ICT-rA2 had sensitivities of 88.6%, 86.5%, and 87.0%, respectively, with specificity values of 84.0%, 92.0%, and 100%, respectively for CVL diagnosis. MAIN CONCLUSIONS: The three antigens selected by us are promising candidates for VL diagnosis regardless of the test format, although the antigen combinations and test parameters may warrant further optimisation.

Evaluation of the recombinant antigens Wb14 and WbT for the capture antibody diagnosis of lymphatic filariasis.

BACKGROUND: Lymphatic filariasis (LF) is a parasitic disease caused mainly by the Wuchereria bancrofti worm and that affects up to 120 million people worldwide. LF is the second cause of chronic global deformity, responsible for 15 million people with lymphedema (elephantiasis) and 25 million men with scrotal hydrocele. Its diagnosis is still associated with numerous difficulties, such as the sample collection periods (microfilaria nocturnal periodicity) and limited diagnostic kits. OBJECTIVES: The aim of this work was to evaluate two recombinant antigens (Wb14 and WbT) as part of an enzyme-linked immunosorbent assay (ELISA) based antibody capture tests for LF. METHODS: The recombinant antigens rWb14 and rWbT were expressed in Escherichia coli BL21 and an antibody capture ELISA was performed. For this, sera were used from microfilaremic individuals with W. bancrofti (MF), chronic pathology (CP), individuals infected with Strongyloides (SP) and healthy controls from endemic (EN) and non-endemic (NE) areas. FINDINGS: Both tests showed similar results, with 90% sensitivity and 96.6% specificity. In comparison with the BM14 ELISA commercial test, the Wb14 and WbT antigens performed with identical sensitivity but greater specificity. Reduced positivity with the CP suggested a potential to monitor cure. This was not confirmed, however, when sera from individuals up to seven years after treatment were assayed. MAIN CONCLUSIONS: The Wb14 and WbT ELISAs were considered efficient and promising diagnostic tests. Due to the importance of antibody capture analysis to evaluate the Global Program to Eliminate Lymphatic Filariasis (GPELF), the tests proposed here appear as great alternatives to the available commercial system.

Pharmacokinetics comparison of two pegylated interferon alfa formulations in healthy volunteers.

BACKGROUND: Several countries have used pegylation technology to improve the pharmacokinetic properties of essential drugs. Recently, a novel interferon alfa-2b protein conjugated to four-branched 12 kDa polyethylene glycol molecules was developed jointly between Cuba and Brazil. The aim of this study was to compare the pharmacokinetic properties of BIP48 (pegylated interferon alfa-2b from Bio-Manguinhos/Fiocruz, Brazil) to those of PEGASYS® (commercially available pegylated interferon alfa-2a from Roche Pharmaceutical). METHODS: This phase I, single-centre, randomized, double-blind crossover trial enrolled 31 healthy male volunteers aged 19 to 35 who were allocated to two stages, either side of a 5-week wash-out period, with each arm lasting 14 consecutive days after subcutaneous administration of 180 µg of one formulation or the other (study or comparator). The main outcome variable was serum pegylated interferon concentrations in 15 samples collected during the course of the study and tested using an enzyme immunoassay. RESULTS: There were no differences between formulations in terms of magnitude or absorption parameters. Analysis of time parameters revealed that BIP48 remained in the body significantly longer than PEGASYS® (Tmax: 73 vs. 54 h [p = 0.0010]; MRT: 133 vs. 115 h [p = 0.0324]; ke: 0.011 vs. 0.013 h(-1) [p = 0.0153]; t1/2: 192 vs. 108 h [p = 0.0218]). CONCLUSION: BIP48 showed the expected pharmacokinetic profile for a pegylated product with a branched molecular structure. Compared to PEGASYS®, the magnitude absorption was similar, but time parameters were consistent with slower elimination. Further studies should be conducted to evaluate the clinical implications of these findings. A phase II-III repeated-dose clinical trial is ongoing to study these findings in patients with chronic hepatitis C virus infection. TRIAL REGISTRATION: This study is registered on the ClinicalTrials.gov platform (accession number NCT01889849 ). This trial was retrospectively registered in June 2013.

Factibilidad del uso de bivalirudina como anticoagulante en soporte vital extracorpóreo / Experience with anticoagulation with bivalirudin during extracorporeal membrane oxygenation

Background: Extracorporeal membrane oxygenation (ECMO) is used with increasing frequency in patients with respiratory and cardiac failure. The achievement of an adequate anticoagulation is critical to avoid patient and circuit complications. Aim: To assess the feasibility and safety of anticoagulation with bivalirudin, as an alternative to unfractionated heparin (UFH), in patient with ECMO. Material and Methods: Observational study, which included all patients receiving anticoagulation with bivalirudin during ECMO, according to a standardized protocol, between august 2015 to May 2016. Results: Bivalirudin was used in 13 out 70 patients connected to ECMO. Ten procedures were for cardiac support and three for respiratory support. Mortality was 43%. ECMO lasted 31 ± 31 days. The time of UFH use before changing to bivalirudin was 7 ± 7 days. The reasons to change to bivalirudin were inadequate levels of partial thromboplastin time (PTT) in nine patients, and heparin induced thrombocytopenia (HIT) in four patients. The time of bivalirudin use was 24 ± 33 days. Per patient, a mean of 2.7 ± 4 oxygenators were changed. These had a useful life of 11.4 and 19.1 days during UFH and bivalirudin use, respectively. The mean bivalirudin dose was 0.08 ± 0.04 mg/kg/h. There was no significant bleeding, thrombosis or circuit obstruction during its use. PTT levels (p < 0.01) and platelet count (p < 0.01) increased significantly after the start of bivalirudin use in patients with UHF resistance and HIT, respectively. Conclusions: Bivalirudin was a safe and efficient drug for anticoagulation during ECMO. It is important to have an alternative drug for anticoagulation in ECMO patients.

Recombinant 60-kDa heat shock protein from Paracoccidioides brasiliensis: is it a good antigen for serological diagnosis of paracoccidioidomycosis?

Paracoccidioides brasiliensis and P. lutzii are fungi that cause paracoccidioidomycosis (PCM), the most prevalent systemic mycosis in South America. For serological diagnosis, although 43-kDa glycoprotein (gp43) is regarded as highly specific for PCM, the occurrence of false negative reactions in sera from patients infected with P. lutzii suggests that preparation with only one antigen is not recommended. Heat shock proteins are feasible alternatives as a second antigen because they are often highly immunogenic. In this study, we evaluated the usefulness of recombinant 60-kDa heat shock protein from P. brasiliensis (rPbHsp60) for the serological diagnosis of PCM. Using western blotting assay, we observed that 77.3% of the sera from PCM patients were positive to rPbHsp60, with 90.9% positivity to recombinant gp43 (rgp43). More importantly, sera from healthy subjects had 27% positivity to rPbHsp60 and none to rgp43. When rPbHsp60 was used in ELISA, we did not observe significant differences between the reactions with sera from PCM patients and healthy subjects, while the difference was clearly evident when the antigen was rgp43. Furthermore, rPbHsp60 was recognized by sera from patients with histoplasmosis, aspergillosis, sporotrichosis or tuberculosis in an ELISA test. These results show that rPbHsp60 is not a good antigen for PCM diagnosis.

Recombinant 60-kDa heat shock protein from Paracoccidioides brasiliensis: is it a good antigen for serological diagnosis of paracoccidioidomycosis?

Paracoccidioides brasiliensis and P. lutzii are fungi that cause paracoccidioidomycosis (PCM), the most prevalent systemic mycosis in South America. For serological diagnosis, although 43-kDa glycoprotein (gp43) is regarded as highly specific for PCM, the occurrence of false negative reactions in sera from patients infected with P. lutzii suggests that preparation with only one antigen is not recommended. Heat shock proteins are feasible alternatives as a second antigen because they are often highly immunogenic. In this study, we evaluated the usefulness of recombinant 60-kDa heat shock protein from P. brasiliensis (rPbHsp60) for the serological diagnosis of PCM. Using western blotting assay, we observed that 77.3% of the sera from PCM patients were positive to rPbHsp60, with 90.9% positivity to recombinant gp43 (rgp43). More importantly, sera from healthy subjects had 27% positivity to rPbHsp60 and none to rgp43. When rPbHsp60 was used in ELISA, we did not observe significant differences between the reactions with sera from PCM patients and healthy subjects, while the difference was clearly evident when the antigen was rgp43. Furthermore, rPbHsp60 was recognized by sera from patients with histoplasmosis, aspergillosis, sporotrichosis or tuberculosis in an ELISA test. These results show that rPbHsp60 is not a good antigen for PCM diagnosis.

Pro-gastrin-releasing peptide and neuron-specific enolase: useful predictors of response to chemotherapy and survival in patients with small cell lung cancer.

PURPOSE: The aim of this study was (1) to evaluate and predict the value of ProGRP and NSE in therapy and survival; (2) as well as to investigate the correlation between the ProGRP mRNA expression in peripheral blood and serum ProGRP protein. METHODS: The study included 122 patients with SCLC without prior therapy. The serum levels of ProGRP and NSE were detected by enzyme-linked immunosorbent assay and eletro-chemiluminescence immunoassay, respectively. The expression of ProGRP mRNA was detected by real-time reverse transcriptase-polymerase chain reaction. RESULTS: Distribution of serum levels of ProGRP, NSE and ProGRP mRNA differed significantly according to tumor size, disease stage and distant metastasis (all P < 0.05), and no association was found between them and gender or age (both P > 0.05). After two courses of chemotherapy, patients of remission and stable groups showed a marked decrease in ProGRP and NSE concentrations (P < 0.05). The ProGRP concentration of patients in progression group was significantly higher than pretreatment level (P < 0.05), while NSE concentration was not. A linear nonparametric (Spearman) correlation test revealed that there was a significant correlation between ProGRP mRNA expression in peripheral blood and serum ProGRP protein level (P < 0.05). Univariate analysis found a statistically significant association of survival with disease stage, distant metastasis, ProGRP and NSE (P < 0.05). Gender, age and tumor size were not prognostic factors (P > 0.05). Multiple Cox regression model analysis found that only disease stage and NSE were significant predictors (P < 0.05). CONCLUSIONS: This study has found that there is a potential role for ProGRP and NSE in both therapy monitoring and predicting survival in SCLC patients.

Expression of a recombinant protein, A2 family, from Leishmania infantum (Jaboticabal strain) and its evaluation in Canine Visceral Leishmaniasis serological test.

This study aimed to express a recombinant A2 family protein of Leishmania chagasi, Jaboticabal strain; test this protein as an antigen in serological assays; and investigate its antigenicity and immunogenicity. A protein coded by an allele of the A2 gene isolated from L. chagasi was expressed in three different strains of Escherichia coli. We used 29 sera samples from Leishmune-vaccinated dogs, 482 sera samples from dogs from endemic areas (positive controls), and 170 sera samples from dogs from non-endemic areas (negative controls) in ELISA tests using soluble Leishmaniaantigen (SLA) and His-A2 as antigen. Expressed proteins showed, by western blotting, the expression of an 11 KDa protein. Sixty-three percent (303/482) of the samples from endemic areas were positive by ELISA His-A2, whereas 93.1% (27/29) of Leishmune®-vaccinated animals were negative by His-A2-ELISA. Anti-A2 antibodies from mice inoculated with the A2 protein were detected in slides containing amastigote forms, but not in slides containing promastigote forms. The A2 recombinant protein from L. chagasi may be a useful tool in the diagnosis of CVL, and further tests regarding the infection stage and the specie of parasite at which the dogs are sampled should provide a better understanding of our results.

Expression of a recombinant protein, A2 family, from Leishmania infantum (Jaboticabal strain) and its evaluation in Canine Visceral Leishmaniasis serological test / Expressão de uma proteína recombinante, da família A2, de Leishmania infantum (amostra Jaboticabal) e suaavaliação no teste sorológico da Leishmaniose Visceral Canina

This study aimed to express a recombinant A2 family protein of Leishmania chagasi, Jaboticabal strain; test this protein as an antigen in serological assays; and investigate its antigenicity and immunogenicity. A protein coded by an allele of the A2 gene isolated from L. chagasi was expressed in three different strains of Escherichia coli. We used 29 sera samples from Leishmune-vaccinated dogs, 482 sera samples from dogs from endemic areas (positive controls), and 170 sera samples from dogs from non-endemic areas (negative controls) in ELISA tests using soluble Leishmaniaantigen (SLA) and His-A2 as antigen. Expressed proteins showed, by western blotting, the expression of an 11 KDa protein. Sixty-three percent (303/482) of the samples from endemic areas were positive by ELISA His-A2, whereas 93.1% (27/29) of Leishmune®-vaccinated animals were negative by His-A2-ELISA. Anti-A2 antibodies from mice inoculated with the A2 protein were detected in slides containing amastigote forms, but not in slides containing promastigote forms. The A2 recombinant protein from L. chagasi may be a useful tool in the diagnosis of CVL, and further tests regarding the infection stage and the specie of parasite at which the dogs are sampled should provide a better understanding of our results.(AU)

Este estudo teve como objetivos expressar uma proteína recombinante da família A2 de Leishmania chagasi, amostra de Jaboticabal-SP; testar essa proteína como antígeno em testes sorológicos; e investigar a antigenicidade e imunogenicidade dessa proteína. Uma proteína codificada por um alelo do gene A2 isolado de L. chagasi foi expressa em três diferentes amostras de Escherichia coli. Foram utilizadas 29 amostras de soro de cães vacinados com Leishmune, 482 amostras de soro de cães de áreas endêmicas (controles positivos), e 170 amostras de soro de cães de áreas não-endêmicas (controles negativos) no ELISA-teste utilizando-se antígeno solúvel total de Leishmania (AST) e His-A2 como antígenos. As proteínas expressas, detectadas pelo western blotting, mostraram a expressão de uma proteína de 11 KDa. Sessenta e três por cento (303/482) das amostras de áreas endêmicas foram positivas pelo ELISA-teste, utilizando-se antígeno His-A2; e 93,1% (27/29) dos animais vacinados com a Leishmune foram negativos. Anticorpos anti-A2 de camundongos inoculados com a proteína A2 foram detectados em lâminas contendo formas amastigotas, enquanto em lâminas contendo formas promastigotas não houve detecção de anticorpos anti-A2. A proteína recombinante A2 pode ser uma ferramenta útil no diagnóstico da LVC, e maiores estudos sobre o estágio de infecção e a espécie de parasita dos cães amostrados devem prover melhor entendimento dos resultados encontrados.(AU)

Immunoagglutination test to diagnose Chagas disease: comparison of different latex-antigen complexes.

OBJECTIVE: To evaluate the diagnostic performance of novel latex-protein complexes obtained from different antigens of Trypanosoma cruzi through immunoagglutination test using a panel of T. cruzi-positive sera, leishmaniasis-positive sera and negative sera for both parasites. METHODS: Complexes' behaviour using total parasite homogenate (TPH), two simple recombinant proteins (RP1 and RP5) and two chimeric recombinant proteins (CP1 and CP2) was comparatively evaluated. The area under ROC curves was used as an index of accuracy. Sensitivity, specificity and discrimination efficiency were assessed. RESULTS: All recombinant antigens showed higher specificity than TPH. The lower specificity of TPH was mainly due to cross-reacting peptides between T. cruzi and Leishmania spp. In turn, all performance indicators were higher for CP1 and CP2 than for RP1 and RP5. The carboxylated latex-CP2 (C2-CP2) complex was able to detect antibodies against T. cruzi. The values of area under ROC curve (0.96), sensitivity (92.3%, 95% CI: 79.4-100.0%) and specificity (84.0%, 95% CI: 67.6-100.0%) indicate that the assay could be used as a screening test. CONCLUSION: The C2-CP2 complex could be an important tool to carry out sero-epidemiological studies.

Optimisation and standardisation of an immunoagglutination assay for the diagnosis of Trypanosoma cruzi infection based on latex-(recombinant antigen) complexes.

OBJECTIVE: To determine the conditions under which the immunoagglutination assay to detect Chagas disease, obtained from a novel latex-(chimeric recombinant antigen) complex, shows greater discrimination between the responses of a positive control serum and a negative control serum. METHODS: The following variables were determined: (i) the sensitisation mechanism, (ii) the emulsifier employed for protein desorption, (iii) the reaction time, (iv) the ionic strength of the reaction medium, (v) the particle concentration, (vi) the presence of blocking agents, (vii) the presence of polyethyleneglycol as potentiator of reaction and (viii) the antigen and antibody concentrations. The search of optimal conditions was investigated by varying one variable at a time. To this effect, monodisperse latex particles sensitised with a recombinant chimeric protein (CP1) were subjected to different conditions. The agglutination reaction was followed by measuring the changes in the optical absorbance by turbidimetry. RESULTS: The maximum discrimination between negative and positive sera was obtained at a reaction time of 5 min, when latex complexes with a concentration of covalently coupled protein of 2.90 mg/m(2) were put in contact with undiluted sera in buffer borate pH 8-20 mm containing glycine (0.1 m) and polyethyleneglycol 8000 (3% w/v). Finally, the latex-protein complex was tested under the obtained optimal conditions, with a panel of Trypanosoma cruzi-positive sera, leishmaniasis-positive sera and -negative sera for both parasites. CONCLUSION: The immunoagglutination test based on the latex-CP1 complex could be used as a screening method for detecting Chagas disease. This test is rapid, easy to implement and could be used under field conditions; but its results should be confirmed by reference techniques like ELISA, HAI, and IFI.

Immunoaffinity in-tube solid phase microextraction coupled with liquid chromatography with fluorescence detection for determination of interferon α in plasma samples.

The present work describes a sensitive and specific automated immunoaffinity in-tube solid-phase microextraction coupled with liquid chromatography with fluorescence detection (LC-FD) method for the determination of interferon α2a in plasma samples for therapeutic drug monitoring. To this end, the intrinsic selectivity of the monoclonal antibodies has been combined with in-tube solid phase microextraction by immobilization of these antibodies into the fused silica capillary. The in-tube SPME variables, such as plasma sample volume, draw/eject volume, number of draw-eject cycles, as well as desorption procedure have been optimized, in order to improve the sensitivity of the proposed method. Analyses of interferon α2a in plasma samples were carried out within 12min (sample preparation and LC analyses). The response of the proposed method was linear over a dynamic range 0.006-3.0MIUmL(-1), with a correlation coefficient of 0.998. The inter-day precision of the method had a coefficient of variation lower than 6.2%. The proposed automated method has adequate analytical sensitivity and selectivity for the determination of interferon α2a in plasma samples for therapeutic drug monitoring. The proposed method was successfully applied to the plasmas samples analyses from patients in therapy with interferon α-2a, demonstrating a rare application of in-tube SPME for biopharmaceutical (protein) analyses.

Dynamics of recombinant hG-CSF in transgenic goat: preliminary study in the founder during hormonally induced lactation.

This study aimed to characterize the dynamic of human granulocyte colony-stimulating factor (hG-CSF) during artificial lactation in a transgenic founder goat and to assess its potential ectopic expression and health. The female secreted 93.9 to 1,474.6 µg hG-CSF per mL of milk. Two peaks of serum hG-CSF (3,470 and 7,390 pg/mL) were detected in the first half of the lactation. Outside of the lactation, hG-CSF was absent from serum, indicating no ectopic expression. During the treatment to induce lactation, transgenic female presented increased neutrophil and lymphocyte blood counts when compared to nontransgenic female. Despite transient neutrophilia, serum biochemistry profiles indicated normal liver and renal functions. Thus, transgenic goat expressed hG-CSF in quantities sufficient for a commercial bioreactor and remained clinically healthy.

Identification of serological biomarkers of infection, disease progression and treatment efficacy for leprosy

Although leprosy is curable with drug treatment, the identification of biomarkers of infection, disease progression and treatment efficacy would greatly help to reduce the overall prevalence of the disease. Reliable biomarkers would also reduce the incidence of grade-2 disability by ensuring that those who are most at risk are diagnosed and treated early or offered repeated treatments in the case of relapse. In this study, we examined the reactivity of sera from lepromatous and tuberculoid leprosy patients (LPs) against a panel of 12 recombinant Mycobacterium leprae proteins and found that six proteins were strongly recognised by multibacillary (MB) patients, while only three were consistently recognised by paucibacillary patients. To better understand the dynamics of patient antibody responses during and after drug therapy, we measured antibody titres to four recombinant proteins, phenolic glycolipid-I and lipoarabinomannan at baseline and up to two years after diagnosis to investigate the temporal changes in the antibody titres. Reactivity patterns to individual antigens and decreases in antibody titres were patient-specific. Antibody titres to proteins declined more rapidly vs. those to carbohydrate and glycolipid antigens. Compared to baseline values, increases in antibody titres were observed during reactional episodes in one individual. Additionally, antibody responses against a subset of antigens that provided a good prognostic indicator of disease progression were analysed in 51 household contacts of MB index cases for up to two years. Although the majority of these contacts showed no change or exhibited decreases in antibody titres, seven individuals developed higher titres towards one or more of these antigens and one individual with progressively higher titres was diagnosed with borderline lepromatous leprosy 19 months after enrolment. The results of this study indicate that antibody titres to specific M. leprae antigens can be used to monitor treatment efficacy in LPs and assess disease progression in those most at risk for developing this disease.

Serologic follow-up of IgG responses against recombinant mycobacterial proteins ML0405, ML2331 and LID-1 in a leprosy hyperendemic area in Venezuela

Leprosy is a slowly evolving disease that occurs mainly in adults. In this study, the Mamaría Village, state of Portuguesa was selected because it had one of the highest prevalence rates (13.25%) of leprosy cases in 1997. Between 1998-2004, 20.2% of the 89 cases registered in this village were less than 15 years old and 61.8% were males. Pau-cibacillary (PB) lesions were the predominant clinical forms identified, although also multibacillary (MB) forms were found. Additionally, 76% of the patients were bacteriologically negative. At the time of diagnosis, 75% of the patients presented with grade 0 disabilities, 23% with grade 1 and 2% with grade 2. Serum samples were collected from 18 PB and 15 MB patients, in addition to 14 family contacts, at the beginning and end of treatment. All the groups were re-evaluated during a three-year period (2008-2011). The proteins used for evaluation were ML0405, ML2331 and LID-1. These mycobacterial proteins were highly specific for Mycobacterium leprae and the IgG responses decreased in both MB and PB patients during multidrug treatment. Our results suggest that these antigens could be used as markers for successful treatment of non-reactional lepromatous patients.

Fibronectin expression is decreased in metastatic renal cell carcinoma following endostatin gene therapy.

Tumor cells induce the disruption of homeostasis between cellular and extracellular compartments to favor tumor progression. The expression of fibronectin (FN), a matrix glycoprotein, is increased in several carcinoma cell types, including renal cell carcinoma (RCC). RCC are highly vascularized tumors and are often amenable to antiangiogenic therapy. Endostatin (ES) is a fragment of collagen XVIII that possesses antiangiogenic activity. In this study, we examined the modulation of FN gene expression by ES gene therapy in a murine metastatic renal cell carcinoma (mRCC) model. Balb/C mice bearing Renca cells were treated with NIH/3T3-LXSN cells or NIH/3T3-LendSN cells. At the end of the experiment, the ES serum levels were measured, and the FN gene expression was assessed using real-time PCR. The tissue FN was evaluated by western blotting and by immunofluorescence analysis. The ES serum levels in treated mice were higher than those in the control group (P<0.05). ES treatment led to significant decreases at the FN mRNA (P<0.001) and protein levels (P<0.01). Here, we demonstrate the ES antitumor effect that is mediated by down-regulation of FN expression in mRCC.

Early diagnosis of congenital toxoplasmosis in newborn infants using IgG subclasses against two Toxoplasma gondii recombinant proteins

The aim of this work was to evaluate the utility of ELISA-based testing of total IgG (IgGt) antibodies and its subclasses (IgG1, IgG2, IgG3 and IgG4) against soluble (STAg) and recombinant (rSAG1 and rMIC3) antigens of Toxoplasma gondii for diagnosing congenital toxoplasmosis. Sera from 217 newborns initially testing positive for specific IgM in filter paper dried blood spots were tested for specific IgM and IgG by ELFA-VIDAS®. Congenital toxoplasmosis was confirmed in 175 and ruled out in 42 infants. The validity of the ELISA tests was determined using the persistence of IgG antibodies (ELFA-VIDAS® kit) at the end of 12 months, which is considered the reference test for the diagnosis of congenital toxoplasmosis. The frequency of positivity with IgGt against STAg, rSAG1 and rMIC3 was found in 97.2%, 96.3% and 80.2%, respectively, of the newborns with confirmed congenital toxoplasmosis. IgG1 reacted with all three antigens, while IgG3 and IgG4 reacted preferentially with rMIC3. Higher mean values of reactivity (sample optical density/cut-off) were found for all subclasses when using rMIC3. All of the antigens showed high sensitivity and low specificity in detecting anti-T. gondii IgGt and IgG1 and low sensitivity and high specificity in detecting IgG3 and IgG4. In conclusion, the combined detection of IgG antibody subclasses against recombinant toxoplasmic antigens may be useful for the early diagnosis of congenital toxoplasmosis.

Early diagnosis of congenital toxoplasmosis in newborn infants using IgG subclasses against two Toxoplasma gondii recombinant proteins.

The aim of this work was to evaluate the utility of ELISA-based testing of total IgG (IgGt) antibodies and its subclasses (IgG1, IgG2, IgG3 and IgG4) against soluble (STAg) and recombinant (rSAG1 and rMIC3) antigens of Toxoplasma gondii for diagnosing congenital toxoplasmosis. Sera from 217 newborns initially testing positive for specific IgM in filter paper dried blood spots were tested for specific IgM and IgG by ELFA-VIDAS. Congenital toxoplasmosis was confirmed in 175 and ruled out in 42 infants. The validity of the ELISA tests was determined using the persistence of IgG antibodies (ELFA-VIDAS kit) at the end of 12 months, which is considered the reference test for the diagnosis of congenital toxoplasmosis. The frequency of positivity with IgGt against STAg, rSAG1 and rMIC3 was found in 97.2%, 96.3% and 80.2%, respectively, of the newborns with confirmed congenital toxoplasmosis. IgG1 reacted with all three antigens, while IgG3 and IgG4 reacted preferentially with rMIC3. Higher mean values of reactivity (sample optical density/cut-off) were found for all subclasses when using rMIC3. All of the antigens showed high sensitivity and low specificity in detecting anti-T. gondii IgGt and IgG1 and low sensitivity and high specificity in detecting IgG3 and IgG4. In conclusion, the combined detection of IgG antibody subclasses against recombinant toxoplasmic antigens may be useful for the early diagnosis of congenital toxoplasmosis.