Leucocytes were obtained from the blood of rabbits, incubated in vitro with soluble antigenic material derived from Shigella paradysenteriae, washed, and transferred to irradiated recipient animals. On the 4th day after cell transfer, agglutinins to Shigella appeared in the sera of the majority of such recipients. The distribution of maximum agglutinin titers was substantially lower in these animals than in recipients of lymph node cells similarly incubated, as reported in earlier studies. Recipients of iodoacetate-treated cells showed no agglutinins. Similar results were obtained with cells of peritoneal exudates obtained 9 days after the intraperitoneal injection of lanolin and light mineral oil.
When cells of peritoneal exudates obtained 1 or 2 days after the injection of this irritant were incubated with the antigenic material and transferred to irradiated recipients, agglutinins did not appear in the sera of the latter. Similar results were obtained with cells from peritoneal exudates obtained a few days after the intraperitoneal injection of heavy mineral oil. The preponderant cell types in the suspensions from these two sources were the polymorphonuclear neutrophils and monocytes, respectively.