Distribution of natural antibody against human neuroblastoma among children with or without neuroblastoma

Background. This study was conducted to examine the distribution of a natur al antibody against neuroblastoma (NB) among Japanese children and to clari fy the clinical significance of the presence of this antibody in the sera d uring treatment in patients with International Neuroblastoma Staging System Stage 4 NB. Procedure. Human sera were obtained from 8 healthy volunteers, 82 patients with nonmalignant surgical diseases, and 35 patients with NB i ncluding 3 with Stage 1 disease, 6 with Stage 2, 7 with Stage 3, 17 with St age 4, and 2 with Stage 4S. This natural antibody was quantified by flow cy tometry and its anti-tumor activity was measured by complement-dependent cy totoxicity (CDC) using TGW cells, a human NB cell line, as the target. Resu lts. IgM antibody and CDC activity against NB could be detected in all sera from healthy volunteers and from patients with non-malignant surgical dise ases who were age >1 year. The amount of IgM antibody and CDC activity in s era from patients with Stage 4 NB at diagnosis consistently was low, most l ikely because of massive absorption by tumor cells. in this group of patien ts, the increased CDC activity detected during treatment was indicative of a favorable factor for survival. Conclusions. A natural antibody against NB appears to exist in the sera of Japanese children. The sequential assessme nt of the levels of this antibody in the sera from Stage 4 NB patients duri ng treatment may serve as a prognostic indicator. Med. Pediatr. Oncol. 36:1 47-148, 2001. (C) 2001 Wiley-Liss, Inc.