Toxocara

Toxocara canis Dog roundworm disease, visceral larva migrans... 

Zhu, X.Q., Jacobs, D.E., Chilton, N.B., Sani, R.A., Cheng, N.A.B.Y. and Gasser, R.B. (1998b) Molecular characterization of a Toxocara variant from cats in Kuala Lumpur, Malaysia. Parasitology 117, 155-164. 

Fig. 9.1. Transmission electron micrographs of parasitic nematode cuticles in transverse section. The structurally distinct layers and the underlying hypodermal syncytia are indicated. Nematodes depicted are the infective larval stage of the canid parasite Toxocara canis and the fourth larval stage of the human filarial parasite Brugia malayi.

The Surface and Secreted Antigens of Toxocara cam s Genes, Protein Structure and Function... 

Several other C-type lectins have since been found in Toxocara (Fig. 12.4). Two are simple variants of TES-32, differing by 13-17% in amino acid sequence but with identical ligand binding sites these have been termed CTL-2 and CTL-3. It has yet to be determined whether these additional lectins are alleles or represent different coding loci, and it has not been established whether they are also secreted. A fourth lectin, CTL-4, corresponds to TES-70 (Loukas et al, 2000), as described below. In addition, there is some evidence that TES-45 and TES-55 are lectins, as detailed below. 

The major surface coat component of Toxocara larvae runs as a set of four closely migrating bands with apparent mobility of 120 kDa on SDS-PAGE. One of these was cloned and sequenced, identified as a serine-rich mucin and designated MUC-1 (Gems and Maizels, 1996). We have now established that there are at least five distinct mucin genes in this parasite, which bear general similarity but important distinctions. Thus, MUC-2, MUC-3, MUC-4 and MUC-5 are all threonine-rich rather than serine-rich, and all five differ in the repeat motifs within the mucin domains. All have similar non-mucin, cysteine-rich domains originally termed NC6 (nematode six-cysteine) domains, and since renamed SXC (six-cysteine), as described below. All mucins have a pair of SXC domains at their C-terminus, while MUC-3 and MUC-5 also have paired N-terminal SXC domains. 

Badley, J.E., Grieve, R.B., Bowman, D.D., Glickman, L.T. and Rockey,J.H. (1987) Analysis of Toxocara canis larval excretory-secretory antigens physicochemical characterization and antibody recognition. Journal of Parasitology 73, 593-600. 

Burke, T.M. and Roberson, E.L. (1985) Prenatal and lactational transmission of Toxocara canis and Ancylostoma caninum experimental infection of the bitch before pregnancy. InternationalJournal for Parasitology 15, 71—75. 

Del Prete, G., De, C.M., Mastromauro, C., Biagiotti, R., Macchia, D., Falagiani, P., Ricci, M. and Romagnani, S. (1991) Purified protein derivative of Mycobacterium tuberculosis and excretory-secretory antigen(s) of Toxocara cams expand human T cells with stable and opposite (type 1 T helper or type 2 T helper) profile of cytokine production. Journal of Clinical Investigation 88, 346-350. 

Falcone, F., Tetteh, K.K.A., Hunt, P., Blaxter, M.L., Loukas, A.C. and Maizels, R.M. (2000) The new subfamily of cathepsin Z-like protease genes includes Tc-cpz-1, a cysteine protease gene expressed in Toxocara canis adults and infective larvae. Experimental Parasitology 94, 201-203. 

Fattah, D.I., Maizels, R.M., McLaren, D.J. and Spry, C.J.F. (1986) Toxocara canis interaction of human eosinophils with infective larvae in vitro. Experimental Parasitology 61, 421-433. 

Gems, D.H. and Maizels, R.M. (1996) An abundantly expressed mucin-like protein from Toxocara canis infective larvae the precursor of the larval surface coat glycoproteins. Proceedings of the National Academy of Sciences USA 93,1665-1670. 

Gillespie, S.H. (1993) The clinical spectrum of human toxocariasis. In Lewis, J.W. and Maizels, R.M. (eds) Toxocara and Toxocariasis Clinical, Epidemiological and Molecular Perspectives. Institute of Biology, London, pp. 55-61. 

Kennedy, M.K., Maizels, R.M., Meghji, M., Young, L., Qureshi, F. and Smith, H.V. (1987) Species-specific and common epitopes on the secreted and surface antigens of Toxocara cati and Toxocara canis infective larvae. Parasite Immunology 9, 407-420. 

Khoo, K.-H., Maizels, R.M., Page, A.P., Taylor, G.W., Rendell, N. and Dell, A. (1991) Characterisation of nematode glycoproteins the major Oglycans of Toxocara excretory secretory antigens are methylated trisaccharides. Glycobiology 1, 163-171. 

Loukas, A., Selzer, P.M. and Maizels, R.M. (1998) Characterisation of Tc-cpl-1, a cathepsin L-like cysteine protease from Toxocara canis infective larvae. Molecular and Biochemical Parasitology 92, 275—289. 

Loukas, A.C., Doedens, A., Hintz, M. and Maizels, R.M. (2000) Identification of a new C-type lectin, TES-70, secreted by infective larvae of Toxocara canis, which binds to host endothelial cells. Parasitology (in press). 

Maizels, R.M. and Page, A.P. (1990) Surface associated glycoproteins from Toxocara canis L2 parasites. Acta Tropica 47, 355-364. 

Maizels, R.M. and Robertson, B.D. (1991) Toxocara canis. secreted glycoconjugate antigens in immunobiology and immunodiagnosis. In Kennedy, M. (ed.) Parasitic Nematodes - Antigens, Membranes and Genes. Taylor and Francis Ltd, London, pp. 95-115. 

Maizels, R.M., de Savigny, D. and Ogilvie, B.M. (1984) Characterization of surface and excretory-secretory antigens of Toxocara canis infective larvae. Parasite Immunology 6, 23-37. 

Maizels, R.M., Tetteh, KK.A. and Loukas, A.C. (2000) Toxocara canis genes expressed by the arrested infective larval stage of a parasitic nematode. InternationalJournal of Parasitology 30, 495-508. 

Nichols, R.L. (1956) The etiology of visceral larva migrans. I. Diagnostic morphology of infective second-stage Toxocara larvae. Journal ofParasitology 42, 349-362. 

Page, A.P. and Maizels, R.M. (1992) Biosynthesis and glycosylation of serine/ threonine-rich secreted proteins from Toxocara canis larvae. Parasitology 105, 297-308. 

Robertson, B.D., Bianco, A.E., McKerrow, J.H. and Maizels, R.M. (1989) Toxocara cams, proteolytic enzymes secreted by the infective larvae in vitro. Experimental Parasitology 69, 30-36. 

Scothorn, M.W., Koutz, F.R. and Groves, H.F. (1965) Prenatal Toxocara canis infection in pups. Journal of the American Veterinary Medical Association 146, 45-48. 

Smith, H.V., Quinn, R., Kusel, J.R. and Girdwood, R.W.A. (1981) The effect of temperature and antimetabolites on antibody binding to the outer surface of second stage Toxocara canis larvae. Molecular and Biochemical Parasitology 4, 183-193. 

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