In intestinal helminth infections, Th2 immune respones are generally associated with mucin secretion for worm expulsion from the host intestine. In particular, IL-4 and IL-13 are the important cytokines related with intestinal mucus production via STAT6 signalling in nematode infections. However, this perspective has never been studied in Gymnophalloides seoi infection. The present study aimed to observe the STAT6 signalling and cytokine responses in C57BL/6 mice, a mouse strain resistant to infection with this trematode. The results showed that worm expulsion occurred actively during days 1-2 post-infection (PI), when goblet cells began to proliferate in the small intestine. The STAT6 gene expression in the mouse spleen became remarkable from day 2 PI. Moreover, G. seoi infection induced a significant increase of IL-13 from day 4 PI in the spleen of infected mice. Our results suggested that goblet cell hyperplasia and worm expulsion in G. seoi-infected mice should be induced by STAT6 signalling, in which IL-13 may be involved as a dominant triggering cytokine.
Animals ; Crassostrea ; Female ; Goblet Cells/*pathology ; Hyperplasia/pathology ; Interleukin-13/*metabolism ; Interleukin-4/*metabolism ; Intestine, Small/immunology ; Metacercariae ; Mice ; Mice, Inbred C57BL ; STAT6 Transcription Factor/*metabolism ; Signal Transduction ; Specific Pathogen-Free Organisms ; Spleen/immunology ; Trematoda/*immunology ; Trichinellosis/*immunology/parasitology

To examine humoral immune responses in the host, we measured serum antibody levels in different strains of mice (ICR, BALB/c, and C3H) experimentally infected with Neodiplostomum seoulense. Specific IgG antibody levels were increased remarkably with little difference among 3 strains of mice infected with N. seoulense from day 7 to 35 post-infection. More target proteins of adult parasites reacted with IgG at the time when the worm recovery decreased compared with other times. More than 20 protein bands, from 14 kDa to 94 kDa in size, were separated from the crude antigen of N. seoulense adults by SDS-PAGE, and among them 26, 30, 35, 43, 54, 67, and 94 kDa proteins were the major antigenic proteins. The results suggest that significant IgG antibody responses occur against N. seoulense in mice and this may be related with expulsion of worms.
Animals ; Antibodies, Helminth/*blood ; Host-Parasite Interactions ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C3H ; Mice, Inbred ICR ; Trematoda/classification ; Trematode Infections/*blood/*immunology

The furcocercus cercariae of Neodiplostomum seoulense (Digenea: Neodiplostomidae) penetrate the skins of tadpoles and shed their tails. The speculated mechanism of this tail loss was physical efforts required to produce a vigorous zigzag motion during skin penetration; no other mechanism has been proposed. We examined the relationship between the host serum and cercarial tail loss. Cercariae of N. seoulense were collected from experimentally infected Segmentina hemisphaerula, and lots of 300 cercariae were cultured in medium 199 contained several types of sera. Cercarial tail degradation was induced in all media, but all the cercariae cultured except those cultured in media containing fetal bovine serum (FBS) died within 48 hr. After 72 hr cultivation in media containing FBS, cercarial tail degradation was induced in 67.0%; in continuous cultivation 13.3% of larvae survived for 7 days. Tail degradation did not occur in the absence of serum and when serum was heat inactivated at 56 degrees C for 30 min. The addition of 20 mM ethylenediaminetetraacetic acid (EDTA) blocked cercarial tail degradation completely. Moreover, the addition of 20 mM MgCl2 restored tail degradation blocked by EDTA. These results suggest that the alternative complement pathway is related with the N. seoulense cercarial tail degradation induced by serum.
Trematoda/*physiology ; Tail/*physiology ; Larva/parasitology ; Complement System Proteins/immunology/*physiology ; Anura/parasitology ; Animals

The enzyme linked immunosorbent assay (ELISA)-inhibition test using a Clonorchis sinensis species-specific mouse monoclonal antibody(MAb), CsHyb 0605-23, showed increased specificity over the conventional ELISA used for serodiagnosis of clonorchiasis. To characterize the corresponding antigen further, the MAb was tested against polysaccharide, protein and glycolipid fractions obtained from a crude extract of C. sinensis adult worms, using chloroform, methanol and phenol extractions. Only the polysaccharide fraction was recognized by the MAb among those fractions. Mild oxidation of the antigen with sodium periodate showed decreased reactivity against the MAb. We concluded that the antigen and antigenic determinants recognized by the MAb are carbohydrates.
parasitology-helminth-trematoda ; Clonorchis sinensis ; Monoclonal antibody ; antigen ; immunology ; carbohydrate ; polysaccharide ; enzyme-linked immunosorbent assay ; diagnosis

In order to observe the antigenic fractions in saline extract of adult Paragonimus westermani, proteins in the crude extract were separated by sodium dodecyl sulfate-polyacylamide gel electrophoresis (SDS-PAGE) in reducing conditions. The separated protein fractions were transferred to nitrocellulose paper on which 20 sera from human paragonimiasis were reacted and immunoblotted. Out of 15 stained protein bands in SDS-PAGE, 7 reacted with the sera. Of 14 reacted bands, 30 kilodalton(kDa) band was the most frequently reacted (95%) and was a strong antigen. Protein bands of 23 and 46 kDa were also strong antigens. Bands of over 150 kDa, 120 kDa, 92 kDa, 86 kDa, 74 kDa, 62 kDa, 51 kDa, 32 kDa, 28 kDa, 16.5 kDa and 15.5 kDa were also reactive but their frequencies of the reaction were variable.
parasitology-helminth-trematoda ; Paragonimus westermani ; immunology ; antigen ; electrophoresis

The sensitivity and specificity of crude and affinity-purified antigens of Clonorchis sinensis obtained from the infected rabbits were studied. Stage-specific antigenic proteins from the eggs, metacercariae and adult worms were characterized by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunosorbent assay (ELISA) The results were as follows: The antibody-binding antigen (ABA) purified from whole worm crude antigen (WWA) by CNBr-activated Sepharose 4B affinity chromatography made 4 specific bands against rabbit anti-sera on Ouchterlony gel diffusion plate, while WWA made 7 bands. Major WWA protein bands by SDS-PAGE were found at 16,300-18,500 and 28,000-29,000 daltons, while major ABA protein bands were at 18,000-21,000 and 29,000-31,000 daltons. The reactivity of ABA with rabbit anti-sera in ELISA was remarkably less sensitive than that of WWA. Molecular weights of egg antigen (EGA), metacercarial antigen (MEA) and adult worm antigen (WWA) of C. sinensis ranged from 15,000-200,000 daltons, 15,000-100,000 daltons and 11,000-80,000 daltons, respectively. Major WWA proteins consisted mainly of polypeptide bands of low molecular weight, less than 31,000 daltons, while those of EGA and MEA consisted of higher molecular weights than 30,000 daltons. The ELISA reactivities of WWA to rabbit anti-sera were remarkably greater than those of MEA. EGA showed negative reaction throughout the experiments. WWA showed higher optical density (O.D.) than 1.0, when reacted with rabbit anti-sera obtained at 4-6 weeks after the infection. In the rabbit anti-sera later than 12 weeks after the infection, the O.D. reacting with WWA showed a plateau without variation. MEA showed relatively low O.D. values (<0.6), when reacted with anti-sera from lightly infected groups throughout the experiments, although there were some weak positive cases (O.D.>0.6) in heavily infected groups. MEA reacted with rabbit anti-sera showed negative results on Ouchterlony gel diffusion plates. Summarizing the above results, it is suggested that the whole worm antigen prepared from the adult worms of C. sinensis is most highly antigenic. However, this antigen might reveal cross reactions with other trematodes such as Paragonimus westermani, therefore, purification of antigenic proteins from the crude antigen is essential to increase the sensitivity and specificity for the immunodiagnosis of clonorchiasis.
parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis ; rabbit ; immunology ; diagnosis ; antigen

This study was undertaken to evaluate the role of peritoneal exudate cells in the transfer of immunity against the liver fluke, Clonorchis sinensis in the inbred BALB/c mice. Ten donor mice were divided into 2 groups. One group consisted of 5 mice was infected orally with 20 metacercariae of C. sinensis, and the other group was injected intraperitoneally with 20 excysted larvae. Thirty days after immunization, the peritoneal exudate cells were obtained from the donor mice. Twenty recipient mice were divided into 4 equal groups for the purpose of primary immunization. The mice of Group I were injected intraperitoneally with 2 x 10(6) peritoneal exudate cells of the donor mice infected orally, those of Group III were injected intraperitoneally with 2 x 10(6) peritoneal exudate cells of the donor mice injected intraperitoneally. Those of Group II were injected orally with 20 metacercariae of C. sinensis. The group IV mice served as controls. Four days after the primary immunization all recipient mice were challenged orally with 20 metacercariae of C. sinensis, and then killed 30 days after the challenging infection. When the peritoneal exudate cells were injected into the recipient mice, pronounced reduction in eggs per gram of the feces was found in the mice of Group I and Group II, but no reduction in those of Group III. In the worm burdens of C. sinensis, the number of flukes found in the mice of Group II was only significantly less than those in the control group(IV). In addition the number of plaque forming cells per spleen in the mice of Group II was found larger than those in Group I. It is likely that donor peritoneal exudate cells transferred to the recipients might result in the production of relative immunity.
parasitology-helminth-trematoda ; Clonorchis sinensis ; immunology ; mouse

Enzyme-linked immunosorbent assay (ELISA) using crude and affinity-purified antigens of adult worms of Paragonimus westermani was performed for infected cat sera with different worm burden, from preinfection to 18th week after infection. Crude antigen was used with supernatant of homogenated worms by freezing-thawing method, and the supernate was centrifuged for l hour at 10,000 rpm at 4C. Affinity-purified antigen (antibody-bound antigen) was prepared from fractions (bound and unbound) of crude antigen by affinity chromatography on CNBr-activated sepharose 4B, and IgG as a ligand was prepared from paragonimiasis cat serum (6 months infected) obtained by ammonium sulfate (40-45 per cent saturated) precipitation method. By SDS-PAGE, crude antigen showed 22 polypeptide fractions while purified antigen showed 4 fractions: 36, 400, 34,700,27,600 and 11,500 in molecular weights. All cats were divided into five groups(G1-G5) by different worm burdens. The mean of recovered worms (+/-SD) and the number of cats in each group are as follows:G1, 2 worms(0) and 4 cats; G2, 4.75(+/-0.66) and eight; G3, 10.75(+/-1.92) and four; G4, 25.20(+/-3.43) and five; G5, 48(+/-12.63) and five cats. The results were summarized as follows: The antibody levels(OD value) increased by worm burden in G1 to G4 generally. However, individual antibody levels were not exactly related with worm burden in all groups, especially there was a wide difference in G4 and G5. These results suggested that the worm burden in G4 (about 20 - 30 worms) is enough to produce antibody maximum in cats of 2~3 kg weight. The antibody levels increased significantly (p<0.05) compared to control sera at the 3rd week in G1 and G2, at the 2nd week in G3, and at the 1st week in G4 and G5. Especially in the 4th week, OD value increased more in G1(p<0.001) and in G2 to G5(p<0.01). In the pattern of antibody levels by ELISA in each group, OD in G1 increased to the 18th week continuously, in G2 OD was maintained same after the 16th week, but in G3 it decresed after the 16th week, and it was maintained same in G4 and G5 after the 14th week. The antibody levels by ELISA with the affinity-purified antigen were higher than those with crude antigen in all groups generally. Especially, the difference of OD values between two antigens was larger from the 4th to the 10th week. In G1 and G2 OD with purified antigen was higher than that with crude one to the 18th week. It was also higher in G3 than that with crude antigen to the 16th week and OD of G4 and G5 were higher before the 14th week than that with crude antigen, however became lower at the 16th week. Consequently, the antibody level in ELISA with affinity-purified antigen was more sensitive at the early weeks after infection and in light infection groups than that with crude antigen.
parasitology-helminth-trematoda ; immunology ; enzyme-linked immunosorbent assay ; Paragonimus westermani ; paragonimiasis ; cat

This study was designed to evaluate the partially purified antigens which were fractionated from crude extract of Paragonimus westermani and to monitor the enzyme-linked immunosorbent assay (ELISA) in experimental cat paragonimiasis during the course of infection as well as before and after chemotherapy. Crude extract of 6-month-old adult P. westermani was fractionated to 5 antigens by successive applications of ammonium sulfate precipitation, ion exchange chromatography and gel filtration. And the cats, 10 in each group, were infected with 60, 30, 15, and 5 metacercariae, then the half of each group was treated with praziquantel 2 times in one day of 100 mg per kilogram of weight on 150 days after the infection. Sera were collected every 10 days. ELISA was performed with the concentration of 2 microgram/ml antigen, 100 times diluted sera and 1,000 times diluted alkaline phosphatase conjugated anti-cat IgG. The results were as follows: Absorbance by ELISA with proteins precipitated by differential concentration of ammonium sulfate was the highest at 51-65 per cent precipitate (PA2), followed by 0-50 per cent precipitate (PA1), 66-80 per cent precipitate (PA3), and 81-90 precipitate (PA4). Unprecipitated protein over 90 per cent ammonium sulfate (PA5) showed the lowest antigenicity. Fractionation of PA1, PA2, and PA3 through the DEAE-cellulose column did not differentiate the antigenic proteins. By passing through the Sephadex G-200 column, PAl and PA2 were fractionated to high molecular weight proteins and those of low molecular weight which showed high absorbance by ELISA (PA1-I, II and PA2- I, II). But PA3 was shown to have a fraction of high molecular weight proteins (PA3-I) which showed high antigenicity. SDS-polyacrylamide gel electrophoresis of PA1-I, PA1-II, PA2-I, PA2-II, PA3-I, and crude extract was performed. Fraction PA1-I was composed of proteins which had the molecular weight of 270 kilodaltons (KD) to 196 KD; of them 220 KD protein was major band. Fraction PA2- I was composed of 255-225 KD, and PA3-I, 255-240 KD, respectively. Fraction PA1-II and fraction PA2-II consisted of 30 KD proteins. Absorbance by ELISA began to increase within 10-20 days after the infection and reached the highest on 140-180 days, then made plateau thereafter. Absorbance by ELISA decreased after praziquantel treatment. In 60 metacercariae infection group, the absorbance had been decreasing, but remained within the positive range during observation period, while those of 30, 15, and 5 metacercariae infection groups turned to negative range. Fraction PA1-II showed the highest antigenicity in ELISA, then fraction PA2-I, fraction PA1-I , fraction PA2-II, fraction PA3-I and crude extract followed. In early phase of infection, the absorbance of fraction PA1-II showed more rapid increase than those of the other fractions and it came to positive range at 20-30 days after infection.
parasitology-helminth-trematoda ; immunology ; enzyme-linked immunosorbent assay ; Paragonimus westermani ; antigen

In order to obtain the most specific and sensitive antigen from crude antigens of Fasciola hepatica for the immunodiagnosis of bovine fascioliasis by the enzyme linked immunosorbent assay(ELISA), phosphate buffered saline extract of F. hepatica was prepared. The crude extract was fractionated into 7 antigens using Sephadex G-100 column chromatography. Seven fractionated antigens were applied to ELISA, precipitation test and intradermal test, respectively. Results obtained are as follows: The specificity (95 per cent confidence interval in negative sera of bovine fascioliasis ; Mean+2 x SD of absorbance ) of the first (MW>150,000) and the second antigens (MW 120,000) were 93.7 per cent, but those of others including crude antigen showed 100 per cen.t. The sensitivity (positive sera of bovine fascioliasis having higher values with compared to the criterion) of the first, the sixth (MW 16,000) and the seventh antigen (MW<5,000) were 91.6 per cent, 87.5 per cent and 0 per cent, respectively, but those of others showed all 100 per cent. The absorbance by ELISA using the fifth antigen (MW 26,000) was 8.43-folds higher in the positive sera than that in the negative sera. This could be used as one of the most specific antigens for the immunodiagnosis of bovine fascioliasis. In Ouchterlony test, precipitin lines were not found in the sera naturally infected with F. hepatica, but some were found in the sera of rabbits immunized with the crude antigens. The numbers of precipitin lines in the sera of rabbits were different in the different fractionated antigens. They were 6 in the crude, 2 in the second and the third antigens, 1 in the forth, the fifth and the sixth antigens and absent in the seventh antigen, respectively. The wheal size for the bovine infected with F. hepatica was 2.46+-0.15 cm in the intradermal test antigen (saline extract of F. hepatica) supplied by the Veterinary Research Institute, Rural Development Administration, Korea. The wheal size of the first, the second and the third antigens were larger than that of intradermal test antigen, whereas those of the forth, the fifth, the sixth and the seventh antigens showed smaller than that of the intradermal test antigen. The results suggest that the fifth antigen may be specific antigen for the immunodiagnosis of bovine fascioliasis.
parasitology-helminth-trematoda ; immunology ; enzyme-linke immunosorbent assay ; diagnosis ; fascioliasis ; Fasciola hepatica