Abstract
Biosynthetic events have been studied in rabbit lymph node cells following antigenic stimulation. The earliest change observed was an increase in the rate of DNA synthesis in the immunized regional lymph node as compared with a control node from the same rabbit. The increase in DNA synthesis was accompanied by an increase of the number of cells in the node, which appeared to be largely the result of entrance of cells from the circulation. Twenty-four hours after primary immunization an increase in the number of ribosomes per cell was observed, accompanied by synthesis of ribosomal RNA. The appearance of messenger RNA for immunoglobulin, as indicated by the parallel increase in the rate of protein synthesis in the cells and in a cell-free system, occurred 3 to 4 days after a secondary injection of antigen. The cell-free system derived from lymph node cells showed a limited degree of polypeptide synthesis with practically no release of complete chains. Release of the nascent peptides was achieved by adding puromycin to a cell-free system containing in vitro-labeled ribosomes. The system demonstrated a high degree of fidelity and the presence of streptomycin did not cause detectable errors of translation.
Footnotes
This investigation was supported by PHS Research Grant HE-04598 from the National Heart Institute and PHS Training Grant 5 T1 AI 154 from the National Institute of Allergy and Infectious Diseases.
