Inhibition of cell proliferation on lens capsules by 4197X-ricin A immunoconjugate.
OBJECTIVE
To evaluate the cytotoxicity of immunotoxin 4197X-ricin A (4197X-RA) and its ability to inhibit protein synthesis and human lens epithelial cell (LEC) proliferation on the inner surface of the lens capsule.


METHODS
Houston Biotechnology, Inc., The Woodlands, Texas.


METHODS
A cell culture system was established using human LECs as a model for the proliferation of remnant LECs that occurs during posterior capsule opacification (PCO) after extracapsular cataract extraction. The LEC culture system was also used in vitro for testing compounds that might inhibit this process in vivo. Human LECs were cultured on the surface of the original lens capsule fixed to collagen. Variability was reduced by dissecting each lens capsule into equivalent halves and exposing the segments to immunotoxin 4197X-RA.


RESULTS
Protein synthesis and LEC proliferation were almost completely inhibited at relatively low 4197X-RA concentrations after short exposure. The inhibitory effects persisted up to 3 weeks after withdrawal of the immunotoxin and after several media exchanges.


CONCLUSIONS
Immunotoxin 4197X-RA may help prevent PCO after primary cataract surgery.
Tarsio
J F
JF
Houston Biotechnology Inc., The Woodlands, Texas 77381, USA.
Kelleher
P J
PJ
Tarsio
M
M
Emery
J M
JM
Lam
D M
DM
D000911:Antibodies, Monoclonal; D018929:Cell Culture Techniques; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003459:Crystallins / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D005500:Follow-Up Studies; D006801:Humans; D000922:Immunotoxins / Q000494:pharmacology*; D007903:Lens Capsule, Crystalline / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D012276:Ricin
D000911:Antibodies, Monoclonal; D003459:Crystallins; D000922:Immunotoxins; D012276:Ricin