Development of immunocytes and immunoglobulin production in long‐term cultures from normal and malignant human lymph nodes

Fifteen human lymph nodes have been grown in vitro. Cells from seven of the nodes eventually developed into apparently permanent lines dominated by cells resembling lymphoblasts. When the results are combined with a previously published series (Pontén, 1967) no difference is found between the frequency at which the phenomenon occurs in lymph nodes obtained from patients without known malignancy (group L), from nodes draining carcinomas (group C), or from malignant lymphomas (group M). It is concluded that the spontaneous establishment of permanent lymphoid cell lines is a characteristic of human lymphoid tissue in general and that no relationship to malignant lymphoma has been proved. A random fibroblastoid growth, apparently unrelated to the appearance of a secondary lymphoid cell production phase, was observed in eight cases, seven of which belonged to group M or C. Five of seven lines were tested repeatedly for globulin production by immunoelectrophoresis and immunoprecipitation combined with autoradiography. Four lines produced immunoglobulins of the IgG type; the fifth, obtained from a tuberculous node, synthesized IgA. Each cell line produced only one detectable molecular species, suggesting a monoclonal origin of the immunoglobulins. The light chains were exclusively of the kappa type, whereas the heavy chains differed with respect to their subgroup specificity.