Affiliations: Preclinical Neuroscience Section, Neuropsychiatry Branch, NIMH Neuroscience Center at St. Elizabeths, Washington, DC 20032 (USA) | Department of Pharmacology, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ 08854 (USA)
Note: [] Present address: Department of Neurosurgery, Medical College of Oita, 1-1 Idaigaoka, Hazama-machi, Oita-gun, Oita, 879-56, Japan.
Note: [] Correspondence: W.J. Freed, NIMH Neuroscience Center at St. Elizabeths, 2700 Martin Luther King Ave., Washington, DC 20032, USA.
Abstract: The A7 cell line is an astrocyte-like cell immortalized by SV40 large T antigen, using retroviral-mediated gene transfer. These cells were transplanted into rat brains, and the graft–host interaction was investigated immunohistochemically. The A7 cells survived focally 2, 6 and 8 weeks after transplantation and retained the immunocytochemical properties observed in vitro. No immunological response was observed. GAP-43 and N-cadherin immunoreactivities were not expressed by A7 cells, but were seen in the matrix within the area of the graft and in the surrounding brain tissue. This indicates that A7 cells may stimulate expression of GAP-43 and N-cadherin immunoreactivity by host tissue. Expression of Thy 1.1 was not observed within the graft site after 2 weeks of survival, but 6 and 8 weeks after transplantation Thy 1.1 was observed within the graft area, indicating the possible co-existence of grafted cells and host tissue. Although indirect, these observations suggest that the A7 cells induce changes in host brain, including possible growth or regeneration of host tissue into the graft area.
