Peripheral blood T and B lymphocytes, in vitro stimulation with phytohemagglutinin, and sensitization with 2,4-dinitrochlorobenzene in Grave's disease.

The percentage and absolute numbers of thymos-dependent (T) and thymos-independent (B) peripheral blood lymphocytes, the in vitro response of lymphocytes to phytohemagglutinin (PHA), and the sensitization with 2,4dinitrochlorobenzene (DNCB) was studied in 26 patients with hyperthyroidism due to Graves' disease. The results showed a normal percentage of both T and B cells and increased absoluted numbers of total lymphocytes in patients compared with 30 healthy controls. The in vitro response to PHA was normal in most patients with the exception of 5 of them who showed an impaired response. All patients developed a reaction of delayed hypersensitivity to DNCB. Our study indicated that there is no general abnormality in cell-mediated immunity in Graves' disease.