Evidence for a loss of recirculating capacity of T-cells after antigenic stimulation.

The distribution of i.v. injected Cr-labelled normal or antigen-activated thymic or thymus-derived cells (T-cells) was studied in isologous recipients. Activated lymphocytes were obtained from the spleens and lymph nodes of lethally X-irradiated allogeneic mice infused 5 days earlier with lymphoid cells. Practically all of the cells of these organs were found to be of donor type origin and they exhibited an increased mean cell volume. Both activated and non-activated T-cells exhibited a high accumulation to spleen and liver within 40 hr after injection into isologous recipients. The non-activated cells also exhibited a high tendency to seek to lymph nodes whereas this capacity was largely absent in the activated cell populations. Since the lymph node seeking capacity of lymphocytes is considered to be a specific trait for the recirculating pool of lymphocytes, it is possible that T-cells may temporarily lose their recirculating capacity when activated by an antigen.