In vitro correlate of tranplantation immunity: spleen cell migration inhibition in the lizard, Calotes Versicolor.

Sensitization to skin allografts in the lizard, Calotes versicolor, was assessed using the in vitro capillary migration inhibition (MI) assay. In the presence of the respective donor antigen, an appreciable degree of MI of sensitized spleen cells was observed as early as 4 days after grafting. A maximum level was attained on day 7 and this response was maintained as long as one month after grafting with only slight fluctuations in the level of MI. When the clinical manifestations of graft rejection culminated on day 35, the degree of MI was still at the maximum level. MI of allograft-sensitized spleen cells is an antigen specific event, and the same level of inhibition is observed whether the specific antigen is provided in the form of intact spleen cells or spleen extract.