Deletion of active human suppressor T lymphocytes from peripheral blood by Sephadex G-10 filtration.

A method for antigen-specific generation of antibody-forming B cells in cultures of human peripheral blood mononuclear (PBM) cells based on the Mishell-Dutton system has recently been established in this laboratory. Comparing PBM cell cultures from healthy donors and from patients with advanced cancer we found the latter to be unresponsive in our assay. Passage of PBM cell suspension over Sephadex G-10 columns restored the response of patient PBM cells to normal levels. The cell population trapped on the column can be recovered and its inhibitory potential demonstrated by its graded addition to cells eluted from the column. The cell responsible for inhibition is sensitive to treatment with OKT8 antibody and complement, indicating its T cell nature. Passage of PBM cells from healthy individuals did not alter antibody responses substantially but made the activation requirements less stringent.