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A M Deelder - One of the best experts on this subject based on the ideXlab platform.
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evaluation of density dependent fecundity in human schistosoma mansoni infections by relating egg counts to Circulating Antigens through deming regression
Parasitology, 2001Co-Authors: K Polman, A M Deelder, S J De Vlas, L Van Lieshout, B GryseelsAbstract:Regression analysis of the relationship of serum Circulating anodic and cathodic Antigens (CAA and CCA), as a possible direct measure of worm burden, and fecal egg counts allows the stud), of phenomena like density-dependent fecundity in human Schistosoma mansoni infections. For a reliable analysis, variations in egg count measurements as well as in Circulating antigen levels have to be taken into account, and an accurate estimation of these variations (represented by parameter λ, in the so-called Deming regression) is of great importance. From a new, extensive data set of repeated measurements of fecal egg counts and CAA and CCA concentrations we determined the respective values for parameter λ, and (re)analysed the relationship between Circulating Antigens and egg counts in 3 data sets from Burundi, Senegal and Zaire by Deming regression. For comparison, ordinary linear regression was performed as well, which considerably biased the regression lines for CCA, but not for CAA. The analyses resulted in a clearly non-proportional relationship between egg counts and CAA, and, to a lesser extent, CCA. Assuming that egg counts and antigen measurements directly reflect egg production and worm burdens, respectively, our findings reinforce the indication of density-dependent fecundity in schistosomiasis mansoni, as suggested by others.
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immunodiagnosis of schistosomiasis by determination of the Circulating Antigens caa and cca in particular in individuals with recent or light infections
Acta Tropica, 2000Co-Authors: L Van Lieshout, A M Polderman, A M DeelderAbstract:In the present paper, we evaluate determination of Circulating anodic (CAA) and cathodic (CCA) antigen for the diagnosis of an active Schistosoma infection in humans, in comparison to the diagnostic performance of parasitological examination and the demonstration of specific antibodies. Illustrated by three different studies, which all deal with the diagnosis of either recent or low intensity infections, we further discuss our experiences with these diagnostic methods. For the diagnosis of recent infections, specific antibody determination showed to be very sensitive, particularly in individuals originating from non-endemic areas. For the assessment of cure and for the diagnosis of active infections in endemic areas, the methods of choice are parasitological examination and CAA or CCA determination. Depending on infection levels of the target population and on logistic conditions, CAA and CCA determination may either replace parasitological examination or, in the case of light infections, may be used as a complementary diagnostic tool.
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day to day variation of egg output and schistosome Circulating Antigens in urine of schistosoma haematobium infected school children from gabon and follow up after chemotherapy
American Journal of Tropical Medicine and Hygiene, 1997Co-Authors: Van Etten L, Peter G Kremsner, Frederik W Krijger, A M DeelderAbstract:A group of 31 school children from Gabon infected with Schistosoma haematobium was examined before praziquantel therapy and followed on days 3, 9, 14, 21, 24, 28, 31 and 35 after therapy. The day-to-day variation of schistosome Circulating Antigens, urinary egg output, and the reagent strip index (RSI, a pathologic marker) was studied in six consecutive pretreatment urine samples collected under standardized conditions. The geometric mean pretreatment for egg output ranged between 97 and 223 eggs per 10 ml of urine; for urine Circulating anodic antigen (CAA) levels this was 44-154 pg/ml and for Circulating cathodic antigen (CCA) levels this was 180-601 pg/ml. On the day of treatment, 97% of the children had viable eggs in their urine, 87% had a positive RSI; positive CAA levels were detected in 61% of the children and positive CCA levels in 77%. A significant correlation was consistently found between RSI and egg counts. Five weeks after chemotherapy egg output, levels of CAA and CCA and the severity of pathologic findings in the lower renal tract, as indicated by the RSI, had decreased significantly in all cases. Our results indicate that egg output in urine is an accurate method for diagnosis of S. haematobium, and additionally show less day-to-day variation than detection by ELISA of schistosome Circulating Antigens in urine.
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detection of the Circulating Antigens caa and cca in a group of dutch travellers with acute schistosomiasis
Tropical Medicine & International Health, 1997Co-Authors: L Van Lieshout, A M Polderman, Leo G Visser, J J Verwey, A M DeelderAbstract:Summary Detection of Circulating anodic antigen (CAA) and Circulating cathodic antigen (CCA) in serum and urine is a highly specific and sensitive alternative for the diagnosis of schistosome infections in endemic areas. However, it is not known how soon after the onset of infection these Antigens can be detected in humans. Neither has there been much research on the detection of these Antigens in individuals normally living in non-endemic areas. We studied the kinetics of CAA and CCA in serum and urine of a group of 28 Dutch tourists, shortly after accidental exposure to a Schistosoma infection during a visit to Mali. Twenty-seven were found to be positive for Schistosoma eggs and/or specific antibodies. From each individual, 1‐4 serum samples were tested for Circulating antigen level, 4‐15 weeks after exposure, and urine samples were also tested from 22 subjects. CAA and CCA levels were quantified by monoclonal antibody-based ELISAs and TRIFMAs. In serum, 23 individuals (85%) were positive at least once for one or both Antigens, but titres were generally very low. CAA and CCA could be detected 5 and 6 weeks after exposure, respectively. Urines were all found to be negative. Almost all cases were negative at 7 months’ follow-up.
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schistosoma analysis of monoclonal antibodies reactive with the Circulating Antigens caa and cca
Parasitology, 1996Co-Authors: A M Deelder, Dieuwke Kornelis, G J Van Dam, Y E Fillie, R J M Van ZeylAbstract:Using spleen cells of mice infected or immunized respectively with cercariae or antigen preparations of Schistosoma mansoni, S. haematobium or S. japonicum monoclonal antibodies (mAbs) were produced against the schistosome gut-associated Antigens CAA (Circulating anodic antigen) and CCA (Circulating cathodic antigen). Fusions nearly exclusively produced either anti-CAA (n = 25) or anti-CCA mAbs (n = 55) with a strong isotype restriction (IgM, IgG1 and IgG3) against both Antigens, the majority of anti-CAA mAbs being IgG1 and the majority of anti-CCA mAbs being IgM. The mAbs, which on the basis of their selection were reactive with multiple carbohydrate epitopes of CAA or CCA, were applied in different immunological techniques including immunofluorescence, a dot immunobinding assay and immuno-electrophoresis to study the epitope repertoire. Anti-CAA mAbs were found to be reactive with 5 different epitopes, none of which occurred as multiple epitopes on eggs. Anti-CCA mAbs, on the other hand, recognized at least 10 different epitopes, while 44% of anti-CCA mAbs recognized epitopes common to the adult worm and the egg. Both CAA- and CCA-epitopes were found to be developmentally expressed at the level of the tegument in cercariae, schistosomula and 5-day-old lung worms, but in the adult worm were primarily found in the gut. Thus, the production of panels of mAbs has not only resulted in the selection of reagents optimally performing in diagnostic immunoassays, but also allowed a more detailed study of the epitope repertoire of these important schistosome Antigens.
Pierre Dorny - One of the best experts on this subject based on the ideXlab platform.
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serological diagnosis of taenia solium in pigs no measurable Circulating Antigens and antibody response following exposure to taenia saginata oncospheres
Veterinary Parasitology, 2017Co-Authors: Pierre Dorny, Veronique Dermauw, A Van Hul, Chiara Trevisan, Sarah GabrielAbstract:Taenia solium taeniasis/cysticercosis is a zoonosis included in the WHO's list of neglected tropical diseases. Accurate diagnostic tools for humans and pigs are needed to monitor intervention outcomes. Currently used diagnostic tools for porcine cysticercosis all have drawbacks. Serological tests are mainly confronted with problems of specificity. More specifically, Circulating antigen detecting tests cross-react with Taenia hydatigena and the possibility of transient Antigens as a result of aborted infections is suspected. Furthermore, the hypothesis has been raised that hatched ingested eggs of other Taenia species may lead to a transient antibody response or to the presence of Circulating antigen detectable by serological tests used for porcine cysticercosis. Here we describe the results of a study that consisted of oral administration of Taenia saginata eggs to five piglets followed by serological testing during five weeks and necropsy aiming at studying possible cross reactions in serological tests used for porcine cysticercosis. The infectivity of the eggs was verified by in vitro hatching and by experimental infection of a calf. One piglet developed acute respiratory disease and died on day 6 post infection. The remaining four piglets did not show any clinical signs until euthanasia. None of the serum samples from four piglets collected between days 0 and 35 post infection gave a positive reaction in the B158/B60 Ag-ELISA and in a commercial Western blot for antibody detection. In conclusion, this study showed that experimental exposure of four pigs to T. saginata eggs did not result in positive serologies for T. solium. These results may help interpreting serological results in monitoring of T. solium control programmes.
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factors associated with the prevalence of Circulating Antigens to porcine cysticercosis in three villages of burkina faso
PLOS Neglected Tropical Diseases, 2011Co-Authors: Rasmané Ganaba, Pierre Dorny, Nicolas Praet, Hélène Carabin, Athanase Millogo, Zékiba Tarnagda, Sennen Hounton, Adama Sow, Pascal Nitiéma, Linda D CowanAbstract:Background : Little is known about porcine cysticercosis in Burkina Faso. We conducted a pilot study to estimate the prevalence of Antigens of Taenia solium cysticercosis and to identify associated factors in pigs of three villages in Burkina Faso, selected to represent different pig management practices: one village where pigs are allowed to roam freely (Batondo), one village where pigs are penned part of the time (Pabre) and one village with limited pig farming (Nyonyogo). Methods/Principal Findings : A clustered random sampling design was used. Data on socio-demographic characteristics (source of drinking water, presence of latrines in the household, type and number of breeding animals) and pig management practices were collected using a standardized questionnaire. Blood samples were collected from one pig per household to determine the presence of Antigens of the larval stages of T. solium by the B158/B60 Ag-ELISA. The associations between seropositivity and socio-demographic and pig management practices were estimated using logistic regression. Proportions of 32.5% (95% CI 25.4–40.3), 39.6% (31.9–47.8), and 0% of pigs, were found positive for the presence of Circulating Antigens of T. solium in Batondo, Pabre, and Nyonyogo, respectively. The results of the logistic regression analyses suggested that people acquire knowledge on porcine cysticercosis following the contamination of their animals. The presence of Antigens in the pigs' sera was not associated with the absence of latrines in the household, the source of drinking water or the status of infection in humans but was associated with pig rearing practices during the rainy season. Conclusions/Significance : The results suggest that education of pig farmers is urgently needed to reduce the prevalence of this infection.
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Factors associated with the prevalence of Circulating Antigens to porcine cysticercosis in three villages of burkina faso.
PLoS Neglected Tropical Diseases, 2011Co-Authors: Rasmané Ganaba, Pierre Dorny, Nicolas Praet, Hélène Carabin, Athanase Millogo, Zékiba Tarnagda, Sennen Hounton, Adama Sow, Pascal Nitiéma, Linda D CowanAbstract:BACKGROUND: little is known about porcine cysticercosis in Burkina Faso. We conducted a pilot study to estimate the prevalence of Antigens of Taenia solium cysticercosis and to identify associated factors in pigs of three villages in Burkina Faso, selected to represent different pig management practices: one village where pigs are allowed to roam freely (Batondo), one village where pigs are penned part of the time (Pabré) and one village with limited pig farming (Nyonyogo). METHODS/PRINCIPAL FINDINGS: a clustered random sampling design was used. Data on socio-demographic characteristics (source of drinking water, presence of latrines in the household, type and number of breeding animals) and pig management practices were collected using a standardized questionnaire. Blood samples were collected from one pig per household to determine the presence of Antigens of the larval stages of T. solium by the B158/B60 Ag-ELISA. The associations between seropositivity and socio-demographic and pig management practices were estimated using logistic regression. Proportions of 32.5% (95% CI 25.4-40.3), 39.6% (31.9-47.8), and 0% of pigs, were found positive for the presence of Circulating Antigens of T. solium in Batondo, Pabré, and Nyonyogo, respectively. The results of the logistic regression analyses suggested that people acquire knowledge on porcine cysticercosis following the contamination of their animals. The presence of Antigens in the pigs' sera was not associated with the absence of latrines in the household, the source of drinking water or the status of infection in humans but was associated with pig rearing practices during the rainy season. CONCLUSIONS/SIGNIFICANCE: the results suggest that education of pig farmers is urgently needed to reduce the prevalence of this infection.
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kinetics of Circulating Antigens in pigs experimentally infected with taenia solium eggs
Veterinary Parasitology, 2003Co-Authors: A Nguekam, A P Zoli, L Vondou, S Pouedet, E Assana, Pierre Dorny, J Brandt, Bertrand Losson, S GeertsAbstract:Abstract Three groups of four piglets were experimentally infected with different doses (103, 104 and 105) of Taenia solium eggs whereas a fourth group of two pigs received gravid proglottids. At autopsy 6 months post infection, the two latter pigs were heavily infected with more than 3000 living cysts per kg of muscle. Ten of the 12 other pigs harboured light infections, i.e. between 2 and 107 cysticerci, 42.4% of which were degenerated. The two remaining pigs had no detectable cysts at post mortem examination. Circulating Antigens (CA) were detected in the sera of all pigs harbouring living cysticerci using a monoclonal antibody based ELISA. CA were first detected between 2 and 6 weeks post infection and remained present generally throughout the entire observation period even in pigs carrying only five to eight living cysts, although strong fluctuations of the level of CA were observed in some pigs. In animals without living cysts at post mortem CA were only detected for a short period and disappeared presumably when the cysticerci became degenerated. The minimum number of living cysts, which could be detected using this ELISA, was 1.
J. Lozano - One of the best experts on this subject based on the ideXlab platform.
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Detection of Circulating Antigens in experimental anisakiasis by two-site enzyme-linked immunosorbent assay
Parasitology Research, 2004Co-Authors: M. Campos, V. Díaz, I. Mañas, B. Morales, L. Martin, J. LozanoAbstract:A two-site enzyme-linked immunosorbent assay (ELISA) based on the avidin-biotin system was developed to study Circulating Antigens in the sera of rats orally or intraperitoneally infected with L3 larvae of Anisakis simplex s.l. Somatic and excretory-secretory Antigens were detected from 24 h post-infection in all infected rats. A direct relationship between the number of larvae inoculated and the concentration of Antigens in the sera was demonstrated; however, the amount of antigen decreased with the course of the infection. Comparative analysis revealed that intraperitoneal inoculation is most appropriate for detecting excretory-secretory Antigens in serum. The minimum concentrations of A. simplex antigen detectable were approximately 2.5 μg/ml for somatic and excretory-secretory Antigens. This antigen detection assay may have application in the diagnosis of anisakiasis.
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Detection of Circulating Antigens in experimental anisakiasis by two-site enzyme-linked immunosorbent assay
Parasitology Research, 2004Co-Authors: M. Campos, V. Díaz, I. Mañas, B. Morales, L. Martin, J. LozanoAbstract:A two-site enzyme-linked immunosorbent assay (ELISA) based on the avidin-biotin system was developed to study Circulating Antigens in the sera of rats orally or intraperitoneally infected with L3 larvae of Anisakis simplex s.l. Somatic and excretory-secretory Antigens were detected from 24 h post-infection in all infected rats. A direct relationship between the number of larvae inoculated and the concentration of Antigens in the sera was demonstrated; however, the amount of antigen decreased with the course of the infection. Comparative analysis revealed that intraperitoneal inoculation is most appropriate for detecting excretory-secretory Antigens in serum. The minimum concentrations of A. simplex antigen detectable were approximately 2.5 μg/ml for somatic and excretory-secretory Antigens. This antigen detection assay may have application in the diagnosis of anisakiasis.
M. Campos - One of the best experts on this subject based on the ideXlab platform.
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Detection of Circulating Antigens in experimental anisakiasis by two-site enzyme-linked immunosorbent assay
Parasitology Research, 2004Co-Authors: M. Campos, V. Díaz, I. Mañas, B. Morales, L. Martin, J. LozanoAbstract:A two-site enzyme-linked immunosorbent assay (ELISA) based on the avidin-biotin system was developed to study Circulating Antigens in the sera of rats orally or intraperitoneally infected with L3 larvae of Anisakis simplex s.l. Somatic and excretory-secretory Antigens were detected from 24 h post-infection in all infected rats. A direct relationship between the number of larvae inoculated and the concentration of Antigens in the sera was demonstrated; however, the amount of antigen decreased with the course of the infection. Comparative analysis revealed that intraperitoneal inoculation is most appropriate for detecting excretory-secretory Antigens in serum. The minimum concentrations of A. simplex antigen detectable were approximately 2.5 μg/ml for somatic and excretory-secretory Antigens. This antigen detection assay may have application in the diagnosis of anisakiasis.
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Detection of Circulating Antigens in experimental anisakiasis by two-site enzyme-linked immunosorbent assay
Parasitology Research, 2004Co-Authors: M. Campos, V. Díaz, I. Mañas, B. Morales, L. Martin, J. LozanoAbstract:A two-site enzyme-linked immunosorbent assay (ELISA) based on the avidin-biotin system was developed to study Circulating Antigens in the sera of rats orally or intraperitoneally infected with L3 larvae of Anisakis simplex s.l. Somatic and excretory-secretory Antigens were detected from 24 h post-infection in all infected rats. A direct relationship between the number of larvae inoculated and the concentration of Antigens in the sera was demonstrated; however, the amount of antigen decreased with the course of the infection. Comparative analysis revealed that intraperitoneal inoculation is most appropriate for detecting excretory-secretory Antigens in serum. The minimum concentrations of A. simplex antigen detectable were approximately 2.5 μg/ml for somatic and excretory-secretory Antigens. This antigen detection assay may have application in the diagnosis of anisakiasis.
Patrocinio Morrondo - One of the best experts on this subject based on the ideXlab platform.
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prevalence of natural ovine fasciolosis shown by demonstrating the presence of serum Circulating Antigens
Parasitology Research, 2003Co-Authors: A Pazsilva, J Pedreira, R Sanchezandrade, J L Suarez, Rosario Panadero, P Diaz, Pablo Diezbanos, C. Lopez, M Arias, Patrocinio MorrondoAbstract:The prevalence of fasciolosis in sheep (Galicia, Northwest Spain) kept under field conditions was determined by using a sandwich-enzyme-linked immunosorbent assay (sELISA). Serum Fasciola hepatica Circulating Antigens were captured by means of a rabbit polyclonal IgG antibody to F. hepatica excretory/secretory products. Results were compared to those obtained by faecal sedimentation and an indirect ELISA (iELISA) and excretory/secretory Antigens. Prevalences were 39.1% by sELISA, 30.4% by faecal sedimentation and 56% by iELISA; 83.3% of the sheep were positive to any one of the three tests. We observed that 59.5% of the sheep examined had active fasciolosis, 29.1% (117) had antigenaemia, 20.4% (82) passed eggs, and 40 (10%) were positive to both probes. We conclude that there is a high prevalence of fasciolosis in sheep from the studied region, and that the combination of sELISA and coprological sedimentation is extremely helpful for demonstrating current fasciolosis, so its application can be strongly recommended for epidemiological surveys.
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prevalence of natural ovine fasciolosis shown by demonstrating the presence of serum Circulating Antigens
Parasitology Research, 2003Co-Authors: A Pazsilva, J Pedreira, R Sanchezandrade, J L Suarez, Rosario Panadero, P Diaz, Pablo Diezbanos, C. Lopez, M Arias, Patrocinio MorrondoAbstract:The prevalence of fasciolosis in sheep (Galicia, Northwest Spain) kept under field conditions was determined by using a sandwich-enzyme-linked immunosorbent assay (sELISA). Serum Fasciola hepatica Circulating Antigens were captured by means of a rabbit polyclonal IgG antibody to F. hepatica excretory/secretory products. Results were compared to those obtained by faecal sedimentation and an indirect ELISA (iELISA) and excretory/secretory Antigens. Prevalences were 39.1% by sELISA, 30.4% by faecal sedimentation and 56% by iELISA; 83.3% of the sheep were positive to any one of the three tests. We observed that 59.5% of the sheep examined had active fasciolosis, 29.1% (117) had antigenaemia, 20.4% (82) passed eggs, and 40 (10%) were positive to both probes. We conclude that there is a high prevalence of fasciolosis in sheep from the studied region, and that the combination of sELISA and coprological sedimentation is extremely helpful for demonstrating current fasciolosis, so its application can be strongly recommended for epidemiological surveys.