Relationship between internalization kinetics and cytotoxicity of mistletoe lectin I to L1210 leukaemia cells
Walzel, H.; Jonas, L.; Rosin, T.; Brock, J.
Folia Biologica 36(3-4): 181-188
1990
ISSN/ISBN: 0015-5500 PMID: 2257937 Document Number: 356360
We have taken two different approaches to the study of the entry of mistletoelectin I (MLI) into murine L1210 leukaemia cells. As detected by cellular protein synthesis and DNA synthesis inhibition, the lectin was cytotoxic to L1210 leukaemia cells. Inhibiton of [3H]leucine and [3H]thymidine incorporation into L1210 cells by MLI was found dose dependent in a concentration range from 10-16 to 10-12 mol/ml. The kinetics of cellular protein synthesis inhibition by MLI was concentration dependent, too. Using preembedding electron microscopy, the binding and intracellular routing of the gold-labelled lectin (MLI.Au15) were studied. MLI was internalized into L1210 leukaemia cells by two different pathways: via coated pits to coated vesicles and via long enclosed invaginations of the plasma membrane.