Cell surface immunoglobulin. XV. The presence of IgM and an IgD‐like molecule on the same cell in murine lymphoid tissue

The present studies were designed to determine whether IgM and “IgD” are on the same cell in the mouse. Thus, radioiodinated murine lymphocytes were treated with anti‐μ and complement to kill IgM‐bearing cells. The dead cells were removed by gradient centrifugation. Results indicate that a portion of the IgD is removed by depleting IgM‐bearing cells. Using cells from thoracic duct or lymph nodes but not spleen, it was evident that some of the double bearers are large lymphocytes.