Effect of serum of mycosis fungoides patients on lymphocyte transformation.

In vitro transformation of peripheral lymphocytes by PHA was usually impaired in mycosis fungoides patients in the infiltrative plaque and tumor stages, while not being significantly impaired in the premycotic stage. A serum factor, reducing transformation by PHA, was demonstrated in 2 of 5 patients in the premycotic stage as well as in 2 and probably 3 of 4 patients in the infiltrative plaque or tumor stage. This serum factor affected both autologous (mycosis fungoides) and normal lymphocytes. The factor tended to be present in patients whose lymphocytes were impaired rather than in those whose lymphocytes were not significantly impaired. The degree of the reduction by mycosis fungoides serum seemed to correlate with the serum concentration of gamma-globulin rather than that of alpha2-globulin. The possible nature and clinical significance of this factor are discussed.