Natural suppressor cells derived from adult spleen and thymus.

Natural suppressor (NS) cell lines were derived from the spleen and thymus of adult mice using procedures previously used to derive NS cells from neonatal spleen. Adult spleen-derived NS cells showed slightly greater suppression of the MLR than neonatal spleen-derived NS cells, and thymus-derived NS cells showed the least suppression. Adult spleen-derived NS cells prevented death from lethal GVHD when administered to sublethally irradiated weanling mice that received an otherwise lethal GVHD provoking inoculum. The stable cell surface phenotype of adult tissue-derived NS cells was similar to that previously described for neonatal and TLI spleen-derived NS cells: strongly positive for Thy 1.2, Ly-5, and asialo-GM1 antigens while negative for Ly-1, Ly-2, L3T4, MAC-1, and surface immunoglobulin.