CNS migration of Diplostomum pseudospathaceum in rainbow trout: Neuro-immunological interactions
- 1Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
Abstract
Rainbow trout Oncorhynchus mykiss serves as second intermediate host to the eyefluke Diplostomum pseudospathaceum, which resides as the metacercarial stage in the fish lens. The parasite uses a fish-eating bird as the definitive host and a pulmonate lymnaeid snail as first intermediate host. The fish achieves the infection when penetrated by cercariae released by the snail. The internal route of the migrating parasite (termed the diplostomule stage) in the fish (from penetration of the external surface to its destination, the eye lens) has remained partly unknown. In order to elucidate the parasite migration we exposed rainbow trout to cercarial invasion, whereafter we traced the diplostomules at selected internal locations by three approaches: (1) dissection of exposed fish and recovery of live parasites, (2) quantitative realtime PCR (qPCR) and (3) histology. We here demonstrate the presence of diplostomules in the CNS (along the spinal cord, medulla oblongata, brain) before it reaches the eye probably along the optic nerve. In the eye the parasite first enters the corpus vitreum and subsequently the lens. The regulation of immune relevant genes (encoding innate and adaptive immune factors) in the central immune organs (spleen and liver) and in tissues affected (CNS and eyes) by the migrating parasites were followed by qPCR. We suggest that the route taken from skin penetration via CNS to the eye elevates the probability of the parasite to survive during migration and reach its destination (eye lens) due to the low concentration of immune effector cells and molecules in CNS.
Supplementary Information: The online version contains supplementary material available at https://doi.org/10.1007/s00436-026-08741-y.
Related
- Learning the interactions underlying multicellular migration using many-body stochastic inference
- QTL spanning the TGF-β2 locus is associated with muscle fiber size in rainbow trout
- Assessment of therapeutic effect and residue depletion kinetics of oxytetracycline dihydrate in rainbow trout, Oncorhynchus mykiss (Walbaum, 1792)
- Molecular characterization of thermo-adapted Novirhabdovirus variants and virulence in vivo in rainbow trout and zebrafish at different temperatures.
- A review on applying immunological methods in animal research
BibTeX
@article{kumas2026migration,
title = {{CNS migration of Diplostomum pseudospathaceum in rainbow trout: Neuro-immunological interactions}},
author = {Kaan Kumas and Klara Hanefeld Egeriis and Sara Kaltoft Palmelund and Magnus Marger and Kurt Buchmann},
journal = {Parasitology Research},
year = {2026},
month = aug,
doi = {10.1007/s00436-026-08741-y},
url = {https://doi.org/10.1007/s00436-026-08741-y},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - CNS migration of Diplostomum pseudospathaceum in rainbow trout: Neuro-immunological interactions
AU - Kaan Kumas
AU - Klara Hanefeld Egeriis
AU - Sara Kaltoft Palmelund
AU - Magnus Marger
AU - Kurt Buchmann
PY - 2026
DA - 2026/08/05
JO - Parasitology Research
DO - 10.1007/s00436-026-08741-y
UR - https://doi.org/10.1007/s00436-026-08741-y
AB - Rainbow trout Oncorhynchus mykiss serves as second intermediate host to the eyefluke Diplostomum pseudospathaceum, which resides as the metacercarial stage in the fish lens. The parasite uses a fish-eating bird as the definitive host and a pulmonate lymnaeid snail as first intermediate host. The fish achieves the infection when penetrated by cercariae released by the snail. The internal route of the migrating parasite (termed the diplostomule stage) in the fish (from penetration of the external surface to its destination, the eye lens) has remained partly unknown. In order to elucidate the parasite migration we exposed rainbow trout to cercarial invasion, whereafter we traced the diplostomules at selected internal locations by three approaches: (1) dissection of exposed fish and recovery of live parasites, (2) quantitative realtime PCR (qPCR) and (3) histology. We here demonstrate the presence of diplostomules in the CNS (along the spinal cord, medulla oblongata, brain) before it reaches the eye probably along the optic nerve. In the eye the parasite first enters the corpus vitreum and subsequently the lens. The regulation of immune relevant genes (encoding innate and adaptive immune factors) in the central immune organs (spleen and liver) and in tissues affected (CNS and eyes) by the migrating parasites were followed by qPCR. We suggest that the route taken from skin penetration via CNS to the eye elevates the probability of the parasite to survive during migration and reach its destination (eye lens) due to the low concentration of immune effector cells and molecules in CNS. Supplementary Information: The online version contains supplementary material available at https://doi.org/10.1007/s00436-026-08741-y.
SN - 0932-0113
SN - 1432-1955
ER -