EXTRUSION OF EARTHWORM CELOMOCYTES - COMPARISON OF THE CELL-POPULATIONS RECOVERED FROM THE SPECIES LUMBRICUS-TERRESTRIS, EISENIA-FETIDA ANDOCTOLASION-TYRTAEUM

Coelomocytes were extruded from three earthworm species: Lumbricus ter restris, Eisenia fetida and Octolasion tyrtaeum. Featuring a simple lo w-vacuum holding device, the proposed methodology allows the recovery of cells with;minimum risk of contamination by faecal material. The vi ability of O. tyrtaeum coelomocytes was highly reproducible (average 9 3%), with an average yield of 0.92 x 10(6) viable cells per earthworm. Cell. viability for L. terrestris and E. fetida averaged similar to 6 8% but the cell yields were higher (respectively 1.67 x 10(6) and 1.28 x 10(6)). Large inter-individual differences in cell yields were obse rved with L, terrestris. Flow cytometric analyses indicated species to species differences in cell populations. Coelomocytes from E, fetida were the smallest with similar to 57% of the total, viable cells recov ered being monitored between 2 and 10 mu m. Large granulated cells (gr eater than or equal to 20 mu m) were detected in fairly large proporti ons in L, terrestris and O, tyrtaeum (similar to 52 and similar to 96% , respectively) while they were less abundant in E, fetida (similar to 9%). Using the vital dye neutral red to assess functional integrity, average cellular uptakes were significantly higher for L, terrestris a nd O, tyrtaeum than for E, fetida (2.94, 2.66 and 0.64 mu g/2 x 10(5) cells, respectively). In summary, the extrusion methodology herein des cribed is applicable for the recovery of coelomocytes from a wide rang e of earthworm sizes and species. Moreover, this study strengthens the fact that extruded coelomocytes could be used for the evaluation of c ell dysfunction and/or cell death following an in vitro and/or in vivo treatment.