In Vitro Tolerance Induction to a Thymus-Dependent Antigen with BALB/c and C₅₇BL/6 Lymph Node Cells: Effect of Tolerogen Concentration and Duration of Exposure

Abstract

Further studies on tolerance induction in vitro to bovine gamma globulin (BGG) in nonadherent BALB/c lymph node cells showed that it was dependent upon both the dose of tolerogen and the time of exposure. Nearly complete tolerance was achieved at a dose of 1.0 mg/ ml and an incubation time of 12-18 hours. When C₅₇BL/6 strain was used for comparison with the BALB/c strain because of its relative ease to become tolerant after in vivo injection of tolerogen, the rate of tolerance induction of its nonadherent lymph node cells was not different from that of BALB/c cells. Thus, in the absence of other host factors, the acquisition of tolerance by lymphocytes is gradual and may reflect the time required for a cell to reach a susceptible phase of the cell cycle and/or the activation of suppressor cells.