Abstract
This review updates an earlier one by Fried (Adv Parasitol 33:91–144, 1994) on metacercarial excystation of trematodes. Our coverage of the salient literature is mainly from 1995 to 2008 and includes significant studies on echinostomatid and non-echinostomatid trematodes. Most of the echinostomatid studies are on species of 37-collar spined Echinostoma, although one study is concerned with a species of Echinochasmus. The non-echinostomatid coverage includes work on species of Paragonimus, Haplorchis, Apatemon, Microphallus, Clonorchis, Riberoia, Maritema, Opisthorchis, and Zygocotyle. Most of the studies were concerned with methods used to excyst the metacercariae of the species being investigated. However, some studies were concerned with metacercarial excystation in order to use the excysted larvae for in vitro cultivation or morphometric studies. Other studies used the excysted larvae for physiological, biochemical, or behavioral work. Several studies were also concerned with elucidating both intrinsic and extrinsic factors which mediate chemical excystation of the metacercarial stage of digenetic trematodes
Similar content being viewed by others
References
Bennett SC, Irwin SWB, Fitzpatrick SM (2003) Tributyltin and copper effects on encystment and in vitro excystment of Parorchis acanthus larvae. J Helminthol 77:291–296
Chung YB, Kong Y, Joo IJ, Cho SY, Kang SY (1995) Excystment of Paragonimus westermani by endogenous cysteine protease. J Parasitol 81:137–142
El Mayas H, Kearn GC (1995) In vitro excystment of the metacercaria of Cryptocotyle convavum from the common goby Pomatoschistus micrcops. J Helminthol 69:285–297
Fredensborg BL, Poulin R (2005) In vitro cultivation of Maritrema novaezealandensis (Microphallidae): the effect of culture medium on excystation, survival and egg production. Parasitol Res 95:310–313
Fried B (1994) Metacercarial excystment of trematodes. Adv Parasitol 33:92–120
Fried B, Roth RM (1974) In vitro excystment of the metacercaria of Parorchis acanthus. J Parasitol 60:465
Fried B, Reddy A (1997) Comparative studies on excystation and morphological features of the metacercariae of Echinostoma paraensei and E. caproni. Int J Parasitol 27:899–901
Fried B, LaTerra R (2002) In vitro and in vivo encystment of the cercariae of Echinostoma caproni. J Parasitol 88:1124–1129
Fried B, Schneck JL (2004) Effects of copper sulphate on in vitro encystment of the cercariae of Echinostoma caproni. J Helminthol 78:371–372
Fried B, Johnson PTJ (2005) In vitro excystment of the metacercariae of Ribeiroia ondatrae. Parasitol Res 95:293–295
Fried B, Peoples RC (2007a) Viability of the encysted metacercariae of Echinostoma caproni judged by light microscopy versus chemical excystation. J Parasitol 93:947
Fried B, Peoples RC (2007b) Effects of various physical and chemical factors on excystation of the encysted metacercariae of Echinostoma caproni. J Parasitol 93:1388–1391
Fried B, Peoples RC (2009) Maintenance, cultivation, and excystation of echinostomes: 2000–2007. In: Fried B, Toledo R (eds) The biology of echinostomes. Springer, New York, pp 112–124
Fried B, Schmidt KA, Sorensen RE (1997) In vivo and ectopic encystment of Echinostoma revolutum and chemical excystation of the metacercariae. J Parasitol 83:251–254
Fried B, Reddy A, Balfour CD (2001) Excystation and distribution of metacercariae of Echinostoma caproni in ICR mice. Comp Parasitol 68:259–261
Fried B, Schneck JL, Ponder EL (2004) Effects of tonicity, digestive enzymes and bile salts, and nutrient media on the survival of excysted metacercariae of Echinostoma caproni. Parasitol Res 93:527–530
Humphries JE, Fried B (1996) Histological and histochemical studies on the paraoesophageal glands in cercariae and metacercariae of Echinostoma revolutum and E. trivolvis. J Helminthol 70:299–301
Ikeda T (2006) Effects of L-type Ca2+ channel antagonists on in vitro excystment of Paragonimus ohirai metacercariae induced by sodium cholate. Parasitol Res 99:336–340
Intapan PM, Maleewong W (2001) In vitro excystation of Paragonimus heterotremus metacercariae. J Parasitol 87:1184–1186
Irwin SWB, McKerr G, Judge BC, Moran I (1984) Studies on metacercarial excystment in Himasthla leptosoma (Trematoda: Echinostomatidae) and newly emerged metacercariae. Int J Parasitol 14:415–421
Kaewpitoon N, Laha T, Kaewkes S, Yongvanit P, Brindley PJ, Loukas A, Sripa B (2008) Characterization of cysteine proteases from the carcinogenic liver fluke, Opisthorchis viverrini. Parasitol Res 102:757–764
Khan RN, Pacut JR, Pung OJ, Lawson V, Marshall M (2003) In vitro excystation of metacercariae of Microphallus turgidus under different physicochemical conditions. Parasitol Res 90:435–437
LaRue GR (1957) The classification of digenetic Trematoda: a review and a new system. Exp Parasitol 6:306–349
Li SY, Chung YB, Chung BS, Choi MH, Yu JR, Hong ST (2004) The involvement of the cysteine proteases of Clonorchis sinensis metacercariae in excystment. Parasitol Res 93:562–566
Negm-Eldin M, Davies RW (2002) Morphology and life cycle of Apatemon hypseleotris species novum from Australia including metacercariae viability and excystment. Dtsch Tierarztl Wochenschr 109:306–314
Ooi HK, Chen CI, Oku Y (2002) Excystation of Haplorchis taichui metacercariae could be elicited by change in pH. Jpn J Vet Res 50:3–7
Peoples RC, Fried B (2008) The effects of various chemical and physical factors on encystment and excystment of Zygocotyle lunata. Parasitol Res 104:899–904
Reddy A, Ponder EL, Fried B (2004) Effects of copper sulfate toxicity on cercariae and metacercariae of Echinostoma caproni and Echinostoma trivolvis and on the survival of Biomphalaria glabrata snails. J Parasitol 90:1332–1337
Rossi ML, Balfour CD, Fried B (2001) Excystation and infectivity of Echinostoma caproni metacercariae after prolonged storage. Comp Parasitol 68:126–129
Saxton TM, Fried B (2008) Excystation of the metacercarial cysts of Echinostoma caproni in a frozen and thawed trypsin–bile salts–cysteine medium. Parasitol Res 102:809–810
Saxton TM, Fried B, Peoples RC (2008) Excystation of the encysted metacercariae of Echinostoma trivolvis and Echinostoma caproni in a trypsin–bile salts–cysteine medium and Morphometric analysis of the excysted larvae. J Parasitol 94:669–671
Schmidt KA, Fried B (1996) Emergence of cercariae of Echinostoma trivolvis from Helisoma trivolvis under different conditions. J Parasitol 82:674–676
Smoluk JL, Fried B (1994) Light microscopic observations of Echinostoma trivolvis (Trematoda) metacercariae during in vitro excystation. Parasitol Res 80:435–438
Ursone R, Fried B (1995) Light and scanning electron microscopy of Echinostoma caproni (Trematoda) during maturation in ICR mice. Parasitol Res 81:45–51
Xiao X, Wang TP, Zheng XD, Shen GJ, Tian ZG (2005) In vivo and in vitro encystment of Echinochasmus liliputanus cercariae and biological activity of the metacercariae. J Parasitol 91:492–498
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Saxton, T., Fried, B. An update on metacercarial excystment of trematodes. Parasitol Res 105, 1185–1191 (2009). https://doi.org/10.1007/s00436-009-1561-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00436-009-1561-3