PRINCIPAL INVESTIGATORS

William J. Freed, Ph.D., Senior Investigator

Chief, Section on Development and Plasticity

Ph.D. - Psychology, University of Kansas

M.A. - Psychology, University of Kansas

B.A. - Psychology, Rutgers University

RESEARCH INTERESTS

Cocaine and Development: We have found that cocaine interferes with proliferation of neural progenitor cells by causing endoplasmic reticulum stress due to P450-mediated metabolism of cocaine. This results in phosphorylation of EIF2α, increased expression of ATF4, and decreased expression of cyclin A. Cocaine produces distinct effects on different cell types, including changes in expression of genes related to cell migration in neural and A2B5+ progenitor cells, and changes related to immune modulation and apoptosis in microglia and astrocytes. In developing rat brains, cocaine causes changes in migration and distribution of both glutamatergic and GABAergic neurons. Thus, cocaine causes multiple effects on neural progenitor cells and other cell types. The mechanisms responsible for these effects, in addition to methods for preventing developmental effects of cocaine in animals, are being explored.

Embryonic Stem Cells: We are developing protocols for inducing differentiation of human embryonic stem cells to both cortical and dopaminergic neurons. Cells thus produced can be employed as in vitro model systems to examine the mechanisms responsible for developmental effects of cocaine.

Cell Lines: We are also developing techniques for producing neural cell lines, using both human embryonic stem cells and rodent primary cultures, and novel oncogene fragments and combinations. We are using techniques which produce cell lines that are not pluripotent, but can differentiate into only one or a few cell types. Cell lines we have produced have been useful as in vitro models, e.g. for examining effects of drugs of abuse, and may eventually be useful for neural transplantation.

Selected Publications:

1. Lee, C.T., Lehrmann, E., Hayashi, T., Amable, R., Tsai, S.Y., Chen, J., et al. (in press). Gene expression profiling reveals distinct cocaine-responsive genes in human fetal CNS cell types. Journal of Addiction Medicine.

2. Lee, C. T., Chen, J., Hayashi, T., Tsai, S. Y., Sanchez, J. F., Errico, S. L., et al. (2008). A mechanism for the inhibition of neural progenitor cell proliferation by cocaine. PLoS Med, 5(6), e117.

3. Vazin, T., Chen, J., Lee, C. T., Amable, R., & Freed, W. J. (2008). Assessment of stromal-derived inducing activity in the generation of dopaminergic neurons from human embryonic stem cells. Stem Cells, 26(6), 1517-1525. Epub 2008 Apr 3.

4. Freed, W. J., Chen, J., Bäckman, C. M., Schwartz, C. M., Vazin, T., Cai, J., et al. (2008). Gene expression profile of neuronal progenitor cells derived from hESCs: activation of chromosome 11p15.5 and comparison to human dopaminergic neurons. PLoS ONE, 3(1), e1422.

5. Lehrmann, E., Colantuoni, C., Deep-Soboslay, A., Becker, K. G., Lowe, R., Huestis, M. A., et al. (2006). Transcriptional changes common to human cocaine, cannabis and phencyclidine abuse. PLoS ONE, 1, e114.

6. Freed, W. J., Zhang, P., Sanchez, J. F., Dillon-Carter, O., Coggiano, M., Errico, S. L., et al. (2005). Truncated N-terminal mutants of SV40 large T antigen as minimal immortalizing agents for CNS cells. Experimental Neurology, 191 (Suppl 1), S45-S59.

7. Zeng, X., Cai, J., Chen, J., Luo, Y., You, Z. B., Fotter, E., et al. (2004). Dopaminergic differentiation of human embryonic stem cells. Stem Cells, 22(6), 925-940.

8. Truckenmiller, M. E., Vawter, M. P., Zhang, P., Conejero-Goldberg, C., Dillon-Carter, O., Morales, N., et al. (2002). AF5, a CNS cell line immortalized with an N-terminal fragment of SV40 large T: growth, differentiation, genetic stability, and gene expression. Experimental Neurology, 175(2), 318-337.

9. Truckenmiller, M. E., Tornatore, C., Wright, R. D., Dillon-Carter, O., Meiners, S., Geller, H. M., et al. (1998). A truncated SV40 large T antigen lacking the p53 binding domain overcomes p53-induced growth arrest and immortalizes primary mesencephalic cells. Cell and Tissue Research, 291(2), 175-189.

10. Perlow, M. J., Freed, W. J., Hoffer, B, J., Seiger, A., Olson, L., & Wyatt RJ. (1979). Brain grafts reduce motor abnormalities produced by destruction of nigrostriatal dopamine system. Science, 204(4393), 643-647.