[Study of cellular immunology in malignant and benign monoclonal gammapathies].

In 25 cases of myeloma and 15 cases of benign paraproteinemia the functional situation of circulating lymphocytes was studied. The technique used was the incorporation of 3H-thymidine after PHA stimulation. E rosette formation and immunoglobulin bearing cells were evaluated. A reduction of 3H-thymidine incorporation in the blastic cells was seen in the patients with myeloma (the difference was statistically significant: p less than 0.001). In benign monoclonal gammopathies the reduction was moderate and was not statistically significant. The different blastic response in vitro in the two group of patients tested confirms that the respective immunocompetent systems clearly differ.