Development of autologous specific reactivity to human neuroblastoma

Antigenic analysis of neuroblastoma cells was performed by autologous typing and indirect immunofluorescent test combined with absorption tests. Serum of a patient with neuroblastoma before treatment showed weak reactivity with cultured autologous neuroblastoma cells, while serum obtained from the same patient 3 months after chemotherapy exhibited strong reactivity with the same indicator cells. This reactivity was absorbed with neither cultured autologous fibroblasts nor allogeneic tumor cells from seven neuroblastoma and two melanoma patients. In addition, cultured hematopoietic cells from two subjects, normal fetal and adult tissues also failed to remove the reactivity. This reactivity, however, was completely removed by the absorption with the cultured autologous neuroblastoma cells and the homogenate, suggesting that these neuroblastoma cells may express tumor specific antigen(s), located on neither normal cells in any stage of the development nor other malignant cells, although the cells and tissues we tested may not be adequate to confirm this.