Rejection of RG-2 gliomas is mediated by microglia and T lymphocytes.
Immunotherapy holds great promise for the treatment of invasive brain tumors, and we are interested specifically in evaluating immune stimulation of microglial cells as one potential strategy. In order to better understand the tumor fighting capabilities of microglial cells, we have compared the responses of syngeneic (Fisher 344) and allogeneic (Wistar) rat strains after intracranial implantation of RG-2 gliomas. Animals were evaluated by clinical examination, magnetic resonance imaging (MRI) and immunohistochemistry for microglial and other immune cell antigens. While lethal RG-2 gliomas developed in all of the Fisher 344 rats, tumors grew variably in the Wistar strain, sometimes reaching considerable sizes, but eventually all of them regressed. Tumor regression was associated with greater numbers of T cells and CD8 positive cells and increases in MHC I and CD4 positive microglia. Our findings suggest that the combined mobilization of peripheral and CNS endogenous immune cells is required for eradicating large intracranial tumors.
Mariani
Christopher L
CL
Department of Neuroscience, College of Medicine, University of Florida, P.O. Box 100244, Gainesville, FL 32611, USA. marianic@mail.vetmed.ufl.edu
Kouri
Joshua G
JG
Streit
Wolfgang J
WJ
D000818:Animals; D001921:Brain / Q000276:immunology / Q000473:pathology; D001932:Brain Neoplasms / Q000276:immunology* / Q000473:pathology; D015704:CD4 Antigens / Q000378:metabolism; D016827:CD8 Antigens / Q000378:metabolism; D045744:Cell Line, Tumor; D005910:Glioma / Q000276:immunology* / Q000473:pathology; D006084:Graft Rejection / Q000276:immunology; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D017628:Microglia / Q000276:immunology*; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology; D051381:Rats; D011916:Rats, Inbred F344; D017208:Rats, Wistar; D013601:T-Lymphocytes / Q000276:immunology*; D014184:Transplantation, Homologous; D014185:Transplantation, Isogeneic
D015704:CD4 Antigens; D016827:CD8 Antigens