Relationship of surface immunoglobulin-bearing cells, plasma cells, and tumor development in anaplastic carcinoma-bearing A/J mice.
Since the humoral immune response has been shown to be associated with immunological enhancement of tumor growth, the study of surface immunoglobulin-bearing cells and plasma cell antigen (PCA)-bearing cells during neoplastic development may provide new approaches to the study of tumor immunology. Peripheral blood was collected every other day from normal and carcinoma-bearing mice. Lymphocytes obtained by Ficoll-Hypaque density centrifugation were assayed for immunoglobulin-bearing cells and PCA-bearing cells using either fluorescein-conjugated goat anti-mouse immunoglobulin or rabbit anti-mouse plasma cell serum and fluorescein-conjugated goat anti-rabbit immunoglobulin. A marked increase in immunoglobulin-bearing cells from tumor-bearing mice was observed by Day 6 and peaked at Day 10. An increase in PCA-bearing cells followed the immunoglobulin-bearing cells increas by 2 to 4 days. The immunoglobulin-bearing cells declined by Day 12, whereas PCA-bearing cells remained elevated through Day 20. Using rabbit anti-mouse plasma cell serum as an immunosuppressive agent, a 4-day prolongation of the mean survival time was observed in rabbit anti-mouse plasma cell serum-treated tumor-bearing mice. This suggests that tumor growth in this model may be related to an active humoral immune response and that suppression of the plasma cell population may prove to be beneficial in the treatment of certain tumors.