Enhancement of haematopoiesis-directed suppressor activity in mice following Bordetella pertussis vaccine.

A single injection of killed whole-cell pertussis vaccine (strain 5374) into CBA mice (H-2k) was shown to induce a drastic depletion of cells in the thymus accompanied by the enhancement of suppressor T-cell activity. Thymus cells obtained from pertussis vaccine-treated mice were shown to inhibit the endogenous and exogenous colony formation in the spleen by haematopoietic stem cells (CFUs). Treatment of thymus cells with the anti-I-Jk alloantiserum against a specific marker of suppressor T-cells plus complement abolished the inhibitory effect on CFUs proliferation and had a stimulatory action on the capacity of the marrow CFUs to form macroscopic haematopoietic colonies in the spleen as compared to controls. These results suggest probable involvement of I-J-bearing suppressor T-cells in haematopoietic disorders induced by pertussis vaccine.