Fish phonephric and blood leukocytes yield a chemiluminescent response (CL) when stimulated appropriately. This response reflects the production of highly reactive oxygen derivatives which contribute to oxygen-dependent killing of targets such as pathogens and parasites. From suspensions of pronephric cells of the Rainbow trout, Oncorhynchus mykiss, we have obtained populations enriched for CL-positive cells. Four bands of cells were obtained using continuous gradients generated with 60% Percoll. The leukocytes of band II showed a very strong PMA-induced CL response, the magnitude of which was several times higher than that observed with equivalent numbers of cells form unseparated pronepheric cell suspensions. Cells present in other bands were not significantly chemiluminescent. Flow cytometric analysis showed that band II contained large granular cells and small granular cells. Cytochemical analysis showed that this subpopulation was greatly enriched with neutrophils. Many band II cells adhere to glass whereas few band III cells do so. The glass-adherent cells loose their CL potential after a few days in vitro, whereas the nonadherent cells retain their CL responsiveness for at least a week in vitro.
Bibliographical noteFunding Information:
Acknowledgements--aWree g ratefult o Joel Willard for his excellenta ssistancew ith the flow cytometrya nalysis,s upportedb y Public Health Service Grant No. ES 00210 from National Institute of EnvironmentaHl ealth Science. This project was funded by Institutional Biomedical Research Support Grant RR 07079t o Oregon State University,a nd by a grant (87-CRSR-2-3043f)r om the U.S.D.A.
- Flow cytometry
- Oncorhynchus mykiss
- Pronephric leukocytes
- Rainbow trout