NGF-PRODUCING TRANSFECTED 3T3 CELLS - BEHAVIORAL AND HISTOLOGICAL ASSESSMENT OF TRANSPLANTS IN NIGRAL LESIONED RATS

The rodent fibroblast clonal cell line, 3T3, was retrovirally transfec ted with the rat nerve growth factor (NGF) gene and selected for NGF s ynthesis, This study tested the hypothesis that transplanted 3T3 cells , transfected to secrete nerve growth factor (3T3(NGF+)), change motor behavioral indices created by striatal denervation in a dose-dependen t fashion, 3T3(NGF+) cells were transplanted into the lateral ventricl e of rats following ipsilateral lesions of the substantia nigra pars c ompacta by stereotaxic injections of 6-hydroxydopamine (10 mu g), an e stablished lesion model, Control groups included vehicle injections an d transplanted untransfected cells, The extent of the lesions was meas ured by determining rotational behavior before and two weeks after tra nsplantation. Immediately prior to transplantation, cells were incubat ed with the fluorescent dye marker, Dil. To assess cell viability, who le brains were cryosectioned and examined for Dil-labeled 3T3 cells us ing fluorescent microscopy, The number of Dil-labeled profiles in five animals per group were counted in at least five noncontiguous section s per animal, From these data a statistically derived estimate of viab le, transplanted 3T3 cells was obtained, The number of surviving trans planted cells correlated with the behavioral changes measured, The 3T3 (NGF+) transplants reduced rotational behavior, while control 3T3 tran splants exacerbated rotational behavior, Thus, while NGF delivery was found to be beneficial, it was apparent that naive 3T3 had detrimental effects. These results underscore the importance of making dose-respo nse measurements when attempting transplant-based modifications of CNS behavior, (C) 1995 Wiley-Liss, Inc.