Journal of Helminthology

Research Papers

The in vitro effect of Khawia sinensis on leucocyte activity in carp (Cyprinus carpio)

N.J. Morleya1 p1 and D. Hoolea1 c1

a1 Parasitology Research Group, Centre for Applied Entomology and Parasitology, Department of Biological Sciences, Keele University, Keele, Staffordshire ST5 5BG, UK

Abstract

The interactions between Khawia sinensis (Cestoda: Caryophyllidea), a pathogenic tapeworm of carp, and host leucocytes has been investigated in vitro by monitoring blastogenesis in pronephric, splenic and thymic lymphocytes and apoptosis of pronephric leucocytes. Both parasite homogenate and excretory/secretory (E/S) products were found to suppress lymphocyte blastogenesis at high concentrations (346.6–98.8 μg ml−1) whilstcell stimulation occurred at low concentrations (49.4–19.8 μg ml−1). This differential affect on leucocyte activity may not be associated with apoptosis in vitro as the parasite E/S products did not significantly affect programmed cell death as monitored by acridine orange and DNA analysis. The parasite effect on leucocyte activity is discussed and its relationship to host susceptibility is evaluated.

(Accepted October 18 1996)

Correspondence:

c1 Author for correspondence.

p1 School of Biological Sciences, Royal Holloway College, University of London, Egham, Surrey, TW20 0EE, UK.