Short Term In vitro Culture of Cryptocaryon irritans, a Protozoan Parasite of Marine Fishes

Abstract

ABSTRACT--Attempts were made to cultivate Cryptocaryon irritans in vitro atAttachment of theronts and subsequent enlargement into trophonts were achieved in two experi ments using strips of trypticase soy agar (TSA, supplemented with 3% NaCl) as an attachment substrate in filtered seawater.In the third experiment, transformation of theronts into trophonts was achieved in an enriched liquid medium composed of 50% filtered seawater, 30% Leibovitz L-15 and 20% fetal calf serum without attachment onto the TSA. Sizes (mean of the trophonts, 114.6were from a recorded size range (50 to 700 vivo. Although only limited numbers of theronts (0.28-1.71%) transformed into trophonts, these results showed that the in vitro culture of C. irritans is potentially feasible as evidenced by the enlargement of the trophonts within the in vivo size range using either a solid medium as an attach ment substrate or a liquid medium without attachment.There is a need, however, to determine essential factors that influence the transformation of the trophonts into viable tomonts capable of producing theronts.

Immobilization antigen vaccine adjuvanted by parasitic heat shock protein 70C confers high protection in fish against cryptocaryonosis

“…4). This indicates that, not only the antibody response but also cellular responses induced by Hsp70C can also enhance the level of protection [41]. In I. multifiliis, CD8 þ leucocytes were located adjacent to the trophonts [42].…”

In vitro culture technique for Cryptocaryon irritans, a parasitic ciliate of marine teleosts

“…were challenged by a method similar to the present one (Yoshinaga & Dickerson 1994) There have been several trials of in vitro cultures of Cryptocaryon irritans and Ichthyophthirius multifiliis, which is the freshwater counterpart of C. irritans and has been much more intensively studied. Theronts of C. irritans were recently transformed in vitro to trophonts on tryptic soy agar blocks in a mixture of seawater, L-15 medium and FCS (Yambot & Song 2004). Theronts of I. multifiliis developed to some extent in tissues excised from fish (Xu et al 2000 (Nielsen & Buchmann 2000).…”

“…In most experiments, the parasite has to be maintained Nielsen & Buchmann (2000), Xu et al (2000) and Yambot & Song (2004) have tried to develop propagation techniques for C. irritans and I. multifiliis. Some of these authors have succeeded in transforming theronts into trophonts and some have succeeded in growing them to a certain extent in artificial media, but development to the tomont and theront stages has not been accomplished under in vitro conditions for either species.…”

Use of Cell Cultures to Study the Interactions of Ciliates with Fish

“…For I. multifiliis, which is from freshwater, EMEM supplemented in various ways was compared with simpler media, including water [137]. For C. irritans, which is a marine ciliate, media were built on L-15 mixed with seawater [138].…”

“…The theronts failed to transform to trophonts. L-15/seawater supplemented with sera supported C. irritans tomonts and trophonts in short-term cultures that either had an attachment substrate (solid medium) or not (liquid medium) [138]. Fetal calf serum (FCS), tilapia serum, or grouper serum was compared.…”