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Biomedical subjects

G V Hillyer

Publications and source records attributed to G V Hillyer.

At least 109 records · Page 6Linked to original sources
PubMed1980

Circumoval precipitin antigens for the diagnosis of schistosomiasis. I. Development of an antiserum reactive with Schistosoma mansoni eggs by the circumoval precipitin test.

A serum was developed which reacts with Schistosoma mansoni eggs by the circumoval precipitin (COP) test. This antiserum to COP antigens was prepared by coupling the COP immune complexes to protein A-Sepharose, isolating the complex with acid buffer, and immunizing rabbits with the eluate. The antiserum reacted with S. mansoni eggs, forming globular bleb and septate precipitates. It also reacted in gel diffusion with a soluble egg antigen preparation of S. mansoni (SEA). Of four SEA antigenic components precipitated one was clearly MSA1. The antiserum to the COP antigens had anti-parasite antibodies absorbable with lyophilized cercariae or eggs. Three human immunoglobulins (IgG, IgM, and IgA) were involved in the COP reaction.

Animals↗
PubMed1980

Immunodiagnosis of infection with Schistosoma haematobium and S. mansoni in man.

We utilized the circumoval precipitin (COP) test, Ouchterlony immunodiffusion, and the enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of human infection with Schistosoma mansoni or S. haematobium, or with both species of schistosome. Only the COP test correctly identified all of those with schistosome infection, although differentiation as to schistosome species was impossible. Circumoval precipitates around S. haematobium eggs from human urine were more numerous and larger than those around S. mansoni eggs obtained from mouse livers. Ouchterlony immunodiffusion with S. mansoni or S. haematobium worm extract failed to diagnose correctly approximately one of every five infected individuals. Mean absorption values of the S. mansoni soluble egg antigen (SEA) used in the ELISA were similar in serum samples from persons infected with either or both species of blood flukes. This suggests that S. mansoni SEA is not species-specific. The ELISA correctly identified, however, 30 of 32 infected individuals, indicating high sensitivity.

Antigens↗
PubMed1980

Antibody responses in murine schistosomiasis and fascioliasis.

Antibody responses in mice with a primary infection of either Schistosoma mansoni or Fasciola hepatica were studied, using antigen preparations from both species. S. mansoni adult worm extracts (Ouchterlony, indrect hemagglutination) detected schistosomiasis in mice by 5-6 weeks, but did not detect fascioliasis through 12 weeks of infection. S. mansoni soluble egg antigen (Ouchterlony, enzyme-linked immunosorbent assay--ELISA) reacted with the sera of mice infected with S. mansoni by 6-7 weeks of infection; only ELISA reacted with the sera of mice infected with F. hepatica (by 3 weeks of infection). The circumoval precipitin test was specific only for mice infected with S. mansoni, being positive by the 9th week of infection. F. hepatica adult worm extract precipitated (Ouchterlony) the sera of mice with schistosomiasis (7 weeks) and fascioliasis (2 weeks).

Animals↗
PubMed1980

Comparison of counterelectrophoresis the enzyme-linked immunosorbent assay, and Kato fecal examination for the diagnosis of fascioliasis in infected mice and rabbits.

The enzyme-linked immunosorbent assay (ELISA), counterelectrophoresis (CEP), and Kato thick-smear stool examinations were used to follow Fasciola hepatica infections in mice and rabbits given or not given chemotherapy. In both mice and rabbits antibody levels were evident by ELISA within 2 weeks of infection, rising to high levels 2 weeks later. Precipitins monitored by CEP were also evident by 2 weeks of infection in mice, but developed more slowly (4-6 weeks) in rabbits. Eggs of F. hepatica were detected at 6-8 weeks of infection in mice and 8-10 weeks in rabbits. In mice with fascioliasis both ELISA and CEP antibody levels tended to drop by 8 weeks of infection, but in rabbits they remained strongly positive for 34 weeks. Mice treated with rafoxanide at 5 weeks of infection rapidly (3-4 weeks) became Kato-, CEP-, and ELISA-negative. Rabbits treated at 26 weeks of infection still had high antibody levels by ELISA 8 weeks later but were Kato-negative and had low precipitin (CEP) levels. ELISA was most sensitive in detecting early infection but CEP was the best indicator of chemotherapeutic success.

Animals↗
PubMed1980

Effect of detergents and acid buffer on the reactivity of Fasciola hepatica antigens.

The effect of glycine-HCl (acid) buffer on antigen extraction and of three commonly used detergents--sodium dodecyl sulphate (SDS), sodium deoxycholate (DOC), and Triton X-100--on the reactivity of a standard Fasciola hepatica adult-worm antigen preparation (FhWWE) was studied. Acid buffer destroyed most of the immunologic reactivity of FhWWE when tested with anti-F. hepatica serum, but apparently did not affect the antigens reactivity with an anti-S. mansoni serum. These studies suggest that elution with acid buffer should be used with caution when FhWWE is the antigenic extract used in antibody-affinity chromatography. Neither Triton X-100 nor DOC appreciably increased the reactivity of FhWWE antigens. In addition, DOC decreased the antigen-antibody interactions. Low concentrations of SDS increased the reactivity of FhWWE, but higher concentrations decreased the antigen-antibody interactions.

Animals↗
PubMed1979

Immunization against Schistosoma mansoni in rhesus monkeys and the requirement of activation of both cell-mediated and humoral mechanisms.

When groups of rhesus monkeys were pretreated with BCG plus hyperimmune serum from monkeys with chronic schistosomiasis or with dialyzable transfer factor from uninfected monkeys plus hyperimmune serum and were challenged with 1,500 cercariae of Schistosoma mansoni, the mean worm burdens were significantly lower than that of untreated controls. Pretreatment with neither BCG alone nor Corynebacterium parvum plus a membrane antigen of adult worms of S. mansoni affected susceptibility. Neither lymphocyte proliferation in the presence of mitogens or schistosome antigen nor serological responsiveness (as measured by gel diffusion, Cercarienhüllenreaktion, circumoval precipitation, or enzyme-linked immunoabsorbent assay) correlated with the degree of resistance of the animals to S. mansoni. The pretreatment procedures used did not cause any abnormal histopathological responses and did not alter the characteristic host response to schistosome eggs in the lungs, liver, mesenteric lymph nodes, and colon.

Animals↗
PubMed1979

Immune responses to Schistosoma mansoni in rhesus monkeys with multiple chronic and early primary infections.

Immunological reactivity in 10 rhesus monkeys was monitored over a 22-week period. Cellular and humoral responses of three animals were studied after primary infection with Schistosoma mansoni. Two uninfected animals served as controls. Increased lymphocyte proliferative responsiveness to mitogens and adult worm antigen was evident during the prepatent period of the infection. Marked suppression of these responses occurred during the acute phase of the disease, but by weeks 9 and 11 the animals were again responsive to mitogens and antigen, respectively, and remained so throughout the remainder of the observation period. No antibody response to various cercarial, adult worm, and egg antigens could be detected until weeks 5 to 7, after which these responses also persisted. Comparison of the immunological reactivities of these animals with primary infection and those of five chronically infected immune animals indicated possible correlations between protective immunity and (i) strong Cercarienhüllenreaktion reactivity, and (ii) lymphocyte proliferative responsiveness to adult worm antigen.

Animals↗
PubMed1979

Immunity in Schistosoma mansoni using antigens of Fasciola hepatica isolated by concanavalin A affinity chromatography.

Antigens of Fasciola hepatica adult worms were chromatographed using concanavalin A-Sepharose 4B. Two unbound peaks appeared in the inclusion volume (DT-1 and DT-2), and one peak was eluted with alpha-methylglucoside (E1-1). At least seven peaks were obtained by isoelectric focusing of E1-1. The largest of these peaks, with an average pI of 4.0, contained the antigens reactive with antibodies to Schistosoma mansoni. Mice immunized with DT-2 or E1-1 and challenged with S. mansoni cercariae developed 39 to 82% fewer worms than controls. DT-1 had no protective effect. Combining DT-1 and DT-2 abolished this protection. These experiments demonstrate that F. hepatica glycoprotein antigens induce in mice significant protection to infection with S. mansoni and offer an interesting approach to the study of vaccines in experimental schistosomiasis.

Animals↗
PubMed1979

The enzyme-linked immunosorbent assay (ELISA) for the immunodiagnosis of schistosomiasis.

The enzyme-linked immunosorbent assay (ELISA) done with soluble egg antigens (SEA) of Schistosoma mansoni was utilized for the detection of infections with schistosomes. The method readily detected experimental infections in NIH outbred, New Zealand black, and New Zealand white mice by 6-10 weeks post-exposure to S. mansoni cercariae. In addition, the test was negative when the sera from 11 Puerto Rican normal controls were examined and was positive in 8 of 10 serum samples from humans with schistosomiasis mansoni. However, extensive cross-reactivity was seen when using serum from humans with fascioliasis, trichinosis, cysticercosis, and echinococcosis. Thus the ELISA test done with SEA as antigen lacks immunologic specificity. For the method to be an effective seroepidemiological tool in areas where these parasites are endemic further purification of the antigen and more extensive understanding of its components are needed.

Animals↗
PubMed1979

Use of immunologic techniques to detect chemotherapeutic success in infections with Fasciola hepatica. II. The enzyme linked immunosorbent assay in infected rats and rabbits.

An enzyme-linked immunosorbent assay (ELISA) was developed using microtiter plates for the immunodiagnosis of fascioliasis in rats and rabbits using extracts of adult worms partially purified by gel filtration chromatography using Sephacryl S-200. Partial purification was necessary to eliminate cross-reactivity with antisera having antibodies to schistosomes. Soft polyvinyl plates clearly gave superior results over hard polystyrine plates. Titers rose by 4 weeks of infection in rats with fascioliasis, by 6 weeks in the case of rabbits, and remained high through at least 12 and 28 weeks, respectively. Titers drop rapidly when animals are successfully treated with a fasciolicidal drug at 4--6 weeks of infection. The results show that the ELISA can be employed for the serodiagnosis of fascioliasis in rats and rabbits and is useful for the prediction of chemotherapeutic success.

Animals↗