Evidence for selective proliferation and histological localisation of B lymphocytes in the human tonsil.

Tonsil lymphocytes are labeled in vitro by 14C-thymidine and, respectively, 14C-uridine. The cells are separated by E-rosetting technique, and the fractions are characterised as B and T lymphocytes. Specific radioactivity was highest in the B lymphocytes, and large Lymphocytes are enriched in this fraction. The B lymphocytes are located in the germinal centres, the perinodular tissue contains T lymphocytes. The results indicate a selective proliferation of B lymphocytes in the germinal centres.