Abomasal secretion in sheep receiving adult<i>Ostertagia circumcincta</i>that are prevented from contact with the mucosa

Simpson, H.V.; Simpson, BJ; Simcock, David C.; Reynolds, Gordon; Pomroy, W.E.

doi:10.1080/00480169.1999.36102

Cited by 28 publications

(12 citation statements)

References 19 publications

(23 reference statements)

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“…Adult parasites were recovered between days 19 and 26 using an agar migration technique (Simpson et al 1999). Briefly, abomasal contents were mixed 2:1 with 3% agar (Bacto Agar, Difco Laboratories, Detroit, MI, USA; final concentration 1% agar), and after solidification, the agar blocks were incubated at 37°C in a saline bath.…”

Section: Provision Of Parasitesmentioning

confidence: 99%

Neutrophil and eosinophil chemotactic factors in the excretory/secretory products of sheep abomasal nematode parasites

2011

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Both eosinophil chemotactic factor (ECF) and neutrophil chemotactic factor (NCF) activities were demonstrated in excretory/secretory (ES) products and homogenates of Haemonchus contortus and Teladorsagia circumcincta larvae and adult worms in a modified checkerboard assay using a micro-chemotaxis chamber. Neutrophil chemotaxis was seen in 28 of 35 experiments and eosinophil chemotaxis in 20 of 38 experiments. Chemokinetic activity for neutrophils and eosinophils (accounting for 40-50% of total cell migration) was also apparent in only three parasite products for each cell type. Significant NCF activity was present in six of seven adult worm ES products (three of four from T. circumcincta and in all three from H. contortus) and ECF activity in four of five adult ES products, whereas fewer L3 incubates, particularly of T. circumcincta, contained chemotactic activity. All parasite homogenates, with one exception for ECF, were chemotactic for both neutrophils and eosinophils. The sequential use of cellulose ultrafiltration membranes of decreasing pore size did not identify precisely the molecular weight of the NCF and ECF but indicated that the active chemicals were greater than 10 kDa and probably greater than 30 kDa.

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Section: Provision Of Parasitesmentioning

confidence: 99%

Neutrophil and eosinophil chemotactic factors in the excretory/secretory products of sheep abomasal nematode parasites

2011

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“…Adult worms were recovered from abomasal contents 21 days after infection, using the technique of Simpson et al (1999). Briefly, abomasal contents were mixed 2:1 with 3% agar and the solidified agar blocks incubated at 37°C in a saline bath.…”

Section: Parasitesmentioning

confidence: 99%

Use of fluorescent lectin binding to distinguish Teladorsagia circumcincta and Haemonchus contortus eggs, third-stage larvae and adult worms

et al. 2011

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Lectin binding to carbohydrates on parasite surfaces has been investigated as a method of distinguishing adult worms, eggs and sheathed and exsheathed L3 of Teladorsagia circumcincta and Haemonchus contortus, economically important abomasal parasites in temperate climates. Both species were maintained as pure laboratory cultures of field isolates from New Zealand. Each of the four life cycle stages could be distinguished by the binding of at least one lectin: adult worms by Sambucus nigra agglutinin (SNA); eggs by peanut agglutinin (PNA), ConcavalinA and Lens culinaris agglutinin (LCA); exsheathed L3 by Griffonia simplicifolia-I lectin (GSL-I) and Lotus tetragonolobus lectin (LTL) and sheathed L3 by Aleuria aurantia lectin (AAL). The whole surface of both adult T. circumcincta and H. contortus strongly bound lectins specific for N-acetylglucosamine (GlcNAc), N-acetylgalactosamine (GalNAc), mannose and fucose, but the two species could be distinguished by SNA binding only to T. circumcincta. Eggs could be distinguished by the binding of mannose-specific PNA to H. contortus and GalNAc-specific LCA and PSA to T. circumcincta eggs. GalNAc, GlcNAc and mannose lectins bound to the cuticle and over the excretory pores of a large proportion of sheathed L3 of both species, but only the H. contortus surface had exposed fucose or sialic acid complexes. The distinguishing lectin for sheathed L3 was AAL, which did not bind to T. circumcincta, but bound weakly to the head region of all fresh H. contortus and to 50-90% after 3 months storage. The cuticle of exsheathed L3 was unresponsive to all 19 lectins, and any binding was restricted to the head and tail regions. L3 exsheathed after 2-4 months storage could be distinguished by the binding of GSL-I and LTL to H. contortus but not to T. circumcincta. Lectin binding could be a useful adjunct in identifying L3, but lacked the consistency to be definitive, whereas it could be further developed as a practical method of distinguishing parasitic nematodes at other stages in the life cycle, particularly the eggs.

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“…L3 were exsheathed in 0.2% sodium hypochlorite at 37°C for 15 min, filtered, washed and resuspended in incubation medium. Adult O. circumcincta were recovered using the technique of Simpson et al (1999). Briefly, abomasal contents were mixed 2:1 with 3% agar (Bacto agar, Difco Laboratories) and, after solidification, the agar blocks were incubated at 37°C in a saline bath.…”

Section: Provision Of Parasitesmentioning

confidence: 99%

Excretory/secretory products of sheep abomasal nematode parasites cause vacuolation and increased neutral red uptake by HeLa cells

et al. 2005

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Excretory/secretory (ES) products of Ostertagia (Teladorsagia) circumcincta and Haemonchus contortus have been implicated in the inhibition of gastric acid secretion and vacuolation, and the loss of parietal cells associated with abomasal parasitism. Vacuolation of epithelial (HeLa) cells caused by adult O. circumcincta or L3 O. circumcincta or H. contortus ES products have been examined by differential interference contrast microscopy and by the neutral red uptake assay. ES products caused visible vacuolation of HeLa cells, and this effect was enhanced by 8 mM NH4Cl. Some parasite ES products caused a marked detachment of cells from the coverslip. At lower concentrations of ES products, neutral red uptake was usually increased above the control, but at higher concentrations of ES products, uptake was often decreased, probably because of cell detachment. Although generally consistent with direct observations of HeLa cell vacuolation by parasite chemicals, neutral red uptake was not a satisfactory quantitative assay.

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Abomasal secretion in sheep receiving adultOstertagia circumcinctathat are prevented from contact with the mucosa

Abstract: Adult O. circumcincta prevented from physical contact with the gastric mucosa by restraint in porous bags are able to raise abomasal pH. This study implicates parasite excretory-secretory products in mediating changes in gastric secretion caused by adult abomasal worms.

Cited by 28 publications

References 19 publications

Neutrophil and eosinophil chemotactic factors in the excretory/secretory products of sheep abomasal nematode parasites

Neutrophil and eosinophil chemotactic factors in the excretory/secretory products of sheep abomasal nematode parasites

Use of fluorescent lectin binding to distinguish Teladorsagia circumcincta and Haemonchus contortus eggs, third-stage larvae and adult worms

Excretory/secretory products of sheep abomasal nematode parasites cause vacuolation and increased neutral red uptake by HeLa cells

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