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Biomedical subjects

B Gottstein

Publications and source records attributed to B Gottstein.

At least 181 records · Page 10Linked to original sources
PubMed1987

Sero-epidemiological survey for alveolar echinococcosis (by Em2-ELISA) of blood donors in an endemic area of Switzerland.

Sera from 17,166 blood donors living in 10 cantons of northern Switzerland in an area endemic for Echinococcus multilocularis were investigated by serological survey for alveolar echinococcosis (AE). A highly species-specific antigen (Em2) and a commonly used E. granulosus hydatid fluid antigen (EgHF) were compared for their suitability in seroepidemiology. EgHF showed a degree of nonspecificity which did not allow direct detection of AE cases. Antibody reaction with Em2 resulted in the detection of 2 asymptomatic clinical cases of AE (seroprevalence 0.01%) within this population of blood donors. A further 4 persons were positive in Em2-ELISA. These 4 persons had negative imaging studies and will be followed serologically and clinically.

Adult↗
PubMed1987

Visceral larva migrans in French adults: a new disease syndrome?

Visceral larva migrans is apparently an endemic disease among adults in southwest France. Thirty-seven adults living in the Midi-Pyrenees region of France were confirmed as having visceral larva migrans based on an increased specific antibody titer to Toxocara canis as detected by enzyme-linked immunosorbent assay (ELISA) and by the Western blot method. The disease was characterized clinically by weakness, pruritus, rash, difficulty breathing, abdominal pain, and pathologically by allergic manifestations including eosinophilia and increased serum immunoglobulin (Ig) E levels. Conditional logistic regression analysis using a control group of 37 hospital patients with other conditions who were individually matched to patients with visceral larva migrans by age and sex revealed an increased risk for visceral larva migrans associated with hunting or living in a household with a hunter (odds ratio (OR) = 9.0, p = 0.02) and with living in a village of less than 500 persons (OR = 5.7, p = 0.04). Owning two or more dogs compared with owning one or no dogs increased the risk of visceral larva migrans for hunting or living in a household with a hunter (OR = 9.6 vs. OR = 4.5) and for persons living in nonhunting households (OR = 2.1 vs. OR = 1.0). These findings, however, could not be duplicated when 60 age- and sex-matched neighbors were used as a second control group.

Adult↗
PubMed1987

Comparison of serologic tests for the diagnosis and follow-up of alveolar hydatid disease.

Alveolar hydatid disease is a serious and often fatal condition caused by infection with the metacestode form of Echinococcus multilocularis. Sera of 21 patients with histologically confirmed disease were tested by an enzyme-linked immunosorbent assay (ELISA) using a semi-purified E. multilocularis antigen fraction (Em2) and by indirect hemagglutination (IHA) and double diffusion (DD5) tests using antigens prepared from E. granulosus cyst fluid. At diagnosis, sera from all 21 patients were positive by Em2 ELISA, 18 (86%) by IHA, and 5 (24%) by DD5. Em2 ELISA detected an antibody response earlier than IHA in 4 of 9 patients from whom sera were available before diagnosis. Following complete surgical resection, Em2 ELISA converted from positive to negative in serum of 2 of 3 patients, while IHA results did not change. Following incomplete resection, 14 of 15 patients tested remained positive by Em2 ELISA, while 12 remained positive by IHA. Of sera from 361 healthy persons from regions free of E. multilocularis, none were positive by Em2 ELISA, while 8% were positive by IHA. Of sera from 59 patients with non-echinococcal parasitic infections, none were positive by Em2 ELISA, while 31% were positive by IHA. Thus, in comparison with tests using E. granulosus antigens, Em2 ELISA appears to be more sensitive and specific for diagnosing AHD, useful on follow-up of resected patients, and positive earlier in the course of disease.

Adult↗
PubMed1987

A double-antibody sandwich ELISA for the detection of Entamoeba histolytica antigen in stool samples of humans.

A double-antibody sandwich ELISA was developed to detect detergent-solubilized antigens of Entamoeba histolytica in stool samples of humans. The test system was evaluated for its methodical and diagnostic sensitivity and specificity. In recovery experiments the lower limit of detection was 400 ng E. histolytica (HK9) protein/ml stool, corresponding to approximately 2000 amoebic trophozoites/ml stool. Samples of 97 patients with suspected intestinal amoebiasis were examined. Specific antigens were detected by ELISA (= positive reaction) in 14 (93%) out of 15 stool samples containing trophozoites of E. histolytica. In contrast, 68 (93%) of 73 samples with other protozoa, including Entamoeba coli, E. hartmanni, Endolimax nana, Iodamoeba buetschlii and Giardia lamblia, did not react in the test system (= negative reaction). The test was shown to detect only trophozoites of E. histolytica and not the cyst stage. This fact could facilitate the differentiation between cyst carriers and persons excreting trophozoites. The results of this preliminary study justify a further large scale evaluation of the test system.

Antigens, Protozoan↗
PubMed1987

Species-specific immunodiagnosis of Taenia solium cysticercosis by ELISA and immunoblotting.

A combination of ELISA and immunoblotting was evaluated for immunodiagnosis of human T. solium cysticercosis. The sensitivity of ELISA for diagnosis of European, Latin-American, Asian and South African patients with cysticercosis was 75% for serum and 55% for cerebrospinal fluid specimen. Antigens originating from cysticerci in pigs from Mexico and South Africa were of adequate applicability. A species-specific confirmation of T. solium cysticercosis by immunoblotting (detection of antibody activity to the 26 K and 8 K bands) was achieved in 92% (serum) and 100% (CSF) of samples positive in ELISA. No antibodies from 147 patients with other helminth infections reacted with the 26 K and the 8 K band in immunoblotting, resulting in a specificity of 100%.

Adult↗
PubMed1986

[New findings on echinococcosis].

The following new aspects of cystic and alveolar echinococcosis (= infections with the metacestode stages of Echinococcus granulosus and E. multilocularis respectively) are reported: identification of a Swiss E. granulosus isolate as "cattle strain" which differs from the "sheep strain"; new observations on proliferation and metastasis formation of larval E. multilocularis; information on chemotherapy of human echinococcosis; recent developments in immunoserology. The latter includes a new technique for serological differential diagnosis of cystic and alveolar echinococcosis, the determination of parasite-specific immunoglobulin classes (IgG, IgM, IgA and IgE) and circulating antigens in ELISA, and the introduction of arc-5 detection in routine serodiagnosis. A highly purified, species-specific antigen from E. multilocularis is now available for seroepidemiological studies.

Anthelmintics↗
PubMed1986

Demonstration of species-specific and cross-reactive components of Taenia solium metacestode antigens.

Analysis of human serum reactivities to antigenic components of soluble Taenia solium metacestode proteins showed the predominant presence of determinants shared by T. solium, Echinococcus multilocularis and E. granulosus. Two polypeptides were demonstrated by SDS-PAGE and Western blot or enzyme-linked immunoelectrotransfer blot (EITB) assay to bind serum and CSF antibodies only from T. solium cysticercosis patients. These species-specific antigenic polypeptides focused between pH 4.6 and 3.9 after resolution by isoelectric focusing followed by EITB. The high species-specificity demonstrated by the present techniques offers the opportunity to confirm serologically an infection by T. solium metacestode.

Animals↗
PubMed1986

An international study on the serological differential diagnosis of human cystic and alveolar echinococcosis.

An enzyme-linked immunosorbent assay (ELISA) for the serological differentiation of cystic (Echinococcus granulosus) and alveolar (E. multilocularis) echinococcosis in man has been evaluated. A discrimination rate of 95.1% was found for 82 sera from patients of geographically disparate endemic areas. This rate was essentially the same as that found for 57 Swiss patients, indicating that inter- and intraspecific strain differences do not influence the test results. The assay method is suitable for immunodiagnostic purposes as well as for seroepidemiological studies.

Adolescent↗
PubMed1985

Purification and characterization of a specific antigen from Echinococcus multilocularis.

A polypeptide (Em2a) purified by affinity chromatography from the Echinococcus multilocularis metacestode showed a high degree of purity as assayed by SDS-PAGE and analytical isoelectrical focusing. A minor contamination with host albumin was revealed. Estimation of relative mol. mass gave a value of 54,000. The isoelectric point was found to be 4.8. Antigenic activity of the polypeptide was demonstrated by immunoprecipitation and western blotting. In these assays the protein was recognized only by homologous sera from patients infected with larval E. multilocularis. This antigen (Em2a) did not react in the ELISA with sera from patients infected with heterologous helminths; these sera were highly cross-reacting with antigen from E. granulosus hydatid fluid. Seventy-three (94%) from 78 investigated patients (alveolar echinococcosis) showed a seropositive reaction with the polypeptide Em2a.

Animals↗
PubMed1984

Determination of parasite-specific immunoglobulins using the ELISA in patients with echinococcosis treated with mebendazole.

Parasite-specific immunoglobulin classes were determined by the ELISA in sera of 19 patients with cystic or alveolar echinococcosis before and after 2 years (+/- 4 months) of continuous treatment with mebendazole at daily doses of 35-50 mg/kg body weight. In the majority of cases IgG decreased and IgA and IgE decreased or disappeared. In contrast, four patients with progressive disease showed reverse tendencies with increasing IgG, IgA and IgE concentrations during the same period.

Animals↗
PubMed1984

An immunoassay for the detection of circulating antigens in human echinococcosis.

An immunoassay (double-antibody-sandwich-ELISA) was developed to detect circulating antigens (CAg) in patients with cystic (Echinococcus granulosus) echinococcosis. Echinococcus antigens derived from heterologous intermediate hosts were used to immunize rabbits and to purify the rabbit-IgG-fraction obtained by affinity-chromatography, thus avoiding major interference with host components. The purified rabbit anti-hydatid IgG was immunosorbed with bovine and human sera. One part of the resulting IgG served as coating agent in a double antibody sandwich-ELISA; the other part, coupled to alkaline phosphatase, as detecting conjugate. The specificity of the antibody reaction was demonstrated by immunoelectrophoresis. Sera of 21 patients with cystic echinococcosis were examined with this test system. In seven of the patients' sera CAg were detected in concentrations ranging between 310 ng and 680 ng protein per ml serum. Comparing pre- and postoperative serum samples obtained from nine patients operated on for cystic echinococcosis, four sera were found to be CAg-positive before and three after operation.

Animals↗
PubMed1984

A collaborative study on larval excretory/secretory antigens of Toxocara canis for the immunodiagnosis of human toxocariasis with ELISA.

Two batches of excretory/secretory (E/S) antigens from second stage larvae of Toxocara canis maintained in vitro were prepared independently in two different laboratories (Zürich and Basel) and analysed in order to obtain information for future efforts to standardize the enzyme-linked immunosorbent assay (ELISA) used for the serodiagnosis of human toxocariasis. SDS-PAGE and "Western-blotting" revealed at least 10 different antigenic components common to the two antigen preparations. However, distinct qualitative and quantitative differences among the two E/S-antigens were observed, since one antigen had a more complex composition than the other. Despite these differences, an accordance of serodiagnosis was obtained in 80% of 25 sera from patients with suspected Toxocara infection tested independently in two different ELISA systems (Basel and Zürich) with the corresponding E/S-antigens. The specificity was 93% as determined (BS-antigen, BS-ELISA) by testing 46 out of 3396 sera from patients with parasitologically proven extra-intestinal helminthic infections. Cross-reactions occurred mainly with sera from patients infected with filariae (5 from 13 cases) exhibiting very high extinction values in their homologous ELISA-system. The reproducibility (intra- and inter-test variations) of two ELISA systems using the corresponding E/S-antigens varied from 5-15%. The results demonstrate that T. canis E/S-antigens may well be applicable for standardization of the ELISA used for the serodiagnosis of human toxocariasis.

Animals↗
PubMed1983

Serological differentiation between Echinococcus granulosus and E. multilocularis infections in man.

An enzyme-linked immunosorbent assay (ELISA) was adapted for the serological differential diagnosis of cystic or alveolar echinococcosis in man caused by Echinococcus granulosus or E. multilocularis respectively. By affinity chromatography using rabbit anti hydatid fluid IgG coupled covalently to CNBr-Sepharose 4B a protein fraction (Em 1) containing shared antigens of both parasites could be isolated from an extract of E. multilocularis metacestode tissue. From the same source another antigen fraction (Em 2) with a high degree of specificity for E. multilocularis was prepared by immunosorption. Antigen Em 1 was equally sensitive for the detection of antibodies against E. granulosus and E. multilocularis, whereas antigen fraction Em 2 appeared to be more specific for E. multilocularis. A correct serological differential diagnosis was achieved in 95% of 57 confirmed cases of human cystic or alveolar echinococcosis by the simultaneous use of both antigen fractions in the ELISA and by comparison of their reactivities.

Animals↗
PubMedDate not supplied

Human cellular immune response to Giardia lamblia.

Human peripheral blood mononuclear cells (PBMC) from two individuals experimentally and one naturally infected with Giardia lamblia responded strongly (in an in vitro lymphocyte proliferation assay) to both heterologous and homologous (parasite origin) G. lamblia antigen stimuli. Proliferative responses to specific antigens as determined by T-cell blotting were due to Giardia T-cell epitopes mostly present in antigens lower than Mr 85,000 and 31,000 in isolates PM and GS/M-H7, respectively. Additionally, Il-2 production of PBMC respective to T lymphocyte subsets under antigen stimulation were determined in one selected patient. Proliferative and lymphokine responses could be associated with CD4+ PBMC depleted of CD8+ T cells and not with PBMC depleted of CD4+ T cells. These preliminary results suggest the initiation of larger studies addressing questions of cell-mediated immune response and the role of lymphokines in human giardiasis.

Animals↗
PubMedDate not supplied

Em2-ELISA for the follow-up of alveolar echinococcosis after complete surgical resection of liver lesions.

Alveolar echinococcosis, a serious and often fatal human disease, can be efficiently cured only by complete surgical resection of the Echinococcus multilocularis lesion. The present study showed that the determination in patients who had undergone surgery of antibody activity directed against the antigen Em2 reliably reflected complete or incomplete surgical resection. From 9 patients with pre-operative positive results in the Em2 enzyme-linked immunosorbent assay (Em2-ELISA) and successful surgical resection, 6 converted to negative within one year and the remaining 3 patients within 4 years after surgery. Six of 7 additional patients who showed recurrences in an average of 6 years after surgery despite assumed complete surgical resection, were positive by Em2-ELISA at the time of recurrence. Discrimination was not possible between these 2 groups of patients when using an ELISA employing crude antigen obtained from E. granulosus hydatid cyst fluid.

Adolescent↗