Immune responses to surface antigens of infective larvae of Ostertagia circumcincta recognized by bile antibodies of sheep immune to challenge were studied in 5-month-old Finn-Dorset male lambs. The sheep were vaccinated subcutaneously with 2 doses of 25 micrograms/kg body weight of surface proteins immunoprecipitated by bile antibodies derived from protected lambs. These antigens were purified from immune complexes by affinity chromatography and then injected with beryllium hydroxide as an adjuvant. The immunized lambs were challenged with 5 x 10(4) L3 and the worm burdens evaluated on day 21 post challenge. These were significantly (P < 0.01) lower in the vaccinated group than in the challenged controls (72% protection). The mucosal and bile IgM, recognizing the L3 surface, showed significantly higher levels in the vaccinated lambs compared to the challenge controls. Mucosal and bile IgA antibody levels against the same antigens were low and no significant differences were observed between vaccinated and control lambs.
[Show abstract][Hide abstract] ABSTRACT: Internal parasites of ruminants have classically been controlled by anthelmintic treatments. Unfortunately,
the misuse of such a handy tool has led to development of anthelmintic resistance, which today presents a
well-reported high prevalence around the world. Apart from this, there are other current concerns related to the use of chemical drugs, such as ecotoxicity and a growing public consumption of ecological - or organic - products. From all these points, it is obvious that alternative and/or complementary measures of parasitic control are required within the framework of an integrated program. This program would use alternative control together with other measures, i.e. grazing management and available epidemiological knowledge, to ensure that parasite control remains effective. Development of vaccines, genetic resistance to parasites, and biological control stand out amongst the alternatives that are currently being studied. Biological control, based on the use of nematophagous fungi acting over parasite larval stages on pasture, is the topic of the present paper. The paper also shows the perspectives for the future use of biological control in Argentina.
Revista de medicina veterinaria 01/2000; 81:270-273.
[Show abstract][Hide abstract] ABSTRACT: Studies on the immunoglobulin (Ig)E immune responses to the gastric nematode, Teladorsagia circumcincta, have demonstrated a major high molecular weight allergen (HMWTc). Cross reactive allergens of similar MW were demonstrated for Trichostrongylus colubriformis and Cooperia curticei, but not for Haemonchus contortus. Purification of HMWTc was achieved by gel-filtration chromatography, and nonreducing SDS-PAGE and Western blot analysis revealed two closely associated bands with a molecular weight of approximately 140-150 kDa. Reduction showed four IgE reactive bands of 120, 50, 45 and 30 kDa, and deglycosylation abrogated the immunoreactivity of the 120 and 30 kDa bands. Ultrastructural immunolocalization by electron microscopy revealed that the IgE reactivity was confined to the cuticular surface of the infective (L3) larvae. ELISA studies to determine the IgE anti-HMWTc responses in lambs during their first grazing season, demonstrated significantly higher IgE antibody in lambs with low accumulative faecal egg count (FEC) compared to animals with high accumulative FEC. These studies provide evidence for a protective function of IgE antibody in Teladorsagia infections in lambs.
[Show abstract][Hide abstract] ABSTRACT: A cDNA encoding a surface-associated antigen was cloned from an Ancylostoma caninum infective larvae (L(3)) cDNA library by immunoscreening with pooled human immune sera. The sera were obtained from individuals living in an Ancylostoma duodenale hookworm-endemic region of China, who had light intensity infections and high antibody titers against A. caninum L(3). Ancylostoma caninum surface-associated antigen-1 is encoded by an 843 bp mRNA with a predicted open reading frame of 162 amino acids. Recombinant Ancylostoma caninum surface-associated antigen-1 was expressed in Escherichia coli and used to prepare a specific antiserum. A Western blot with anti-Ancylostoma caninum surface-associated antigen-1 specific antiserum showed that native Ancylostoma caninum surface-associated antigen-1 protein is expressed by both L(3) and adult hookworms; RT-PCR confirmed that the mRNA is transcribed in both stages. In adult hookworms, the protein localised to the basal layer of the cuticle and hypodermis of adult worms. Serological analysis determined that recombinant Ancylostoma caninum surface-associated antigen-1 protein is recognised by 61% of human sera from a Necator americanus hookworm endemic area in China, indicating the antigen is immunodominant. Anti-Ancylostoma caninum surface-associated antigen-1 antiserum partially inhibited (46.7%) invasion of hookworm L(3) into dog skin in vitro. Together these results suggest that Ancylostoma caninum surface-associated antigen-1 offers promise as a protective vaccine antigen.
International Journal for Parasitology 09/2004; 34(9):1037-45. DOI:10.1016/j.ijpara.2004.04.015 · 3.87 Impact Factor
Na Young Kim, Dong Suk Chang, Yeonsu Kim, Chang Hwan Kim, Gyeung Haeng Hur, Jai Myung Yang, Sungho Shin
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