Contribution à l'étude de virus de mollusques marins apparentés ...

Publication 1 : Production of monoclonal antibodies against Iymphocystis
disease virus (LDV, /ridoviridae). Application to early and reliable LDV
titration.
Journal of Fish Diseases, sous presse.
1 2 3 2
R.M. LE DEUFF , B. DESPRES , S. H. MORTENSEN, V. BOULO, E.
BACHERE 2 & E. MIALHE 4 1 Laboratoire de Génétique, Aquaculture et Pathologie,
Unité de Recherche en Pathologie et Immunologie Générales, IFREMER, BP133, F-
17390 La Tremblade, France, 2Défenses et Résistances des Invertébrés Marins,
lFREMER-CNRS UM2, CP71, F-34000 Montpellier, France, 3/nstitute of Marine
Research, Department of Aquaculture, PO Box 1870, N-5024 Bergen-Nordnes,
Norway and 4CENAIM ESPOL, Campus Politecnico, P.o. Box 09-01-4519,
Guayaquil, Ecuador, South America
Correspondence : R.M. Le Deuff, Laboratoire de Génétique, Aquaculture et
Pathologie, Unité de Recherche en Pathologie et Immunologie Générales,
IFREMER, BP133, F-17390 La Tremblade, France. Tel: (33) 46.36.98.36. Fax: (33)
46.36.37.51
Abstract. Monoclonal antibodies against Lymphocystis disease virus (LDV) were
prepared using infected BF2 cell cultures as antigen source for immunisation of mice
and hybridoma screening. The screening was performed by indirect
immunofluorescent assay (lIFA) on non-infected (negative screening test), and on
early (3 days) and delayed early (9 days) infected BF2 cells (positive screening tests).
Ten LDV specific antibody producing clones were selected. Clones were
characterized according to the immunofluorescent patterns of antibodies produced.
Sensitive and reliable titration of LDV was possible with Iwo of the monoclonal
antibodies obtained (II A2 and 15D II C9).
Introduction
Lymphocystis disease is a contagious viral infection described from a variety of fresh,
brackish and sea water teleost fish species (Anders, 1989). This disease is caused by
Lymphocystis disease virus (LDV), an lridovirus which composition, structure and
biological properties are weil described (Mid lige & Malsberger, 1968 ; Berthiaurne,
Alain, & Robin, 1984 ; Samalecos, 1986 ; Flügel, 1985). LDVs have been classified
in the Iridoviridae family as a separate genus, Lymphocystivirus, associated to fishes
(Francki, Fauquet, Knudson & Brown, 1991), and Iwo different LDV types have
been proposed on the basis of restriction enzyme DNA cleavage patterns (Darai,
Anders, Koch, Delius, Gelderblom, Samalecos & FlUgel, 1983).
ln addition to LDV, sorne of the Iridoviridae, such as Frog Virus 3 (FV3) and Chilo
Iridescent Virus (CIV) have been thoroughly studied and characterized (Essani &
Granoff, 1989 ; Devauchelle, Attias, Monnier, Barray, Cerutti, Guerillon & Orange­
Balange, 1985) due to the availability of susceptible cell lines. Others, have only
been described structurally. These are mainly associated with invertebrates, and their
impact on host populations are not weil known. Jt is also presurned that viruses
morphologically similar to LDV, were involved in gill disease which caused a total
disappearance of the Portuguese oyster, Crassostrea angulata (Lmk) from French
waters between 1967 and 1973 (Comps, Bonami, Vago & Campillo, 1976).
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