The purpose of present study is to analyse the clinical picture and the state of cell-mediated immunity on pulmonary atypical mycobacteriosis.
Cell-mediated immunity was examined by the methods of tuberculin skin test and in vitro thymidine uptake of lymphocytes stimulated with PPD and PHA.
The study subjects were 26 cases of pulmonary atypical mycobacteriosis, who were admitted to Keio University Hospital from 1966 to 1976.
The results of the clinical analysis of 26 cases was closely similar to those previously reported in Japan, except the fact that the frequency of subjective complaints of this disease at the first medical examirration was higher than that of pulmonary tuberculosis in the anther's material. Tuberculin tests were examined for 21 patients of which twelve reacted positive, five negative and four doubtful positive. Among cases with negative and doubtful tuberculin reactions and showed clinical improvement, their tuberculin reaction turned to positive, and in one case who showed worsening, tuberculin reaction converted to negative.
Lymphocyte response to PPD and PHA was carried out by the following methods. Blood was taken from 11 cases of pulmonary atypical mycobacteriosis, from 13 adults patients with pulmonary tuberculosis and from 10 healthy hospital employees in whom the skin reactivity to PPD was positive. All donors had not been tuberculin tested for some weeks prior to the examination. Preparation of lymphocytes was carried out by the method of gravity sedimentation. Culture were set up in glass tubes containing 1×10⁶-lymphocytes in 2ml of Eagle' medium supplemented with 10% fetal-calf-serum and with 100 us PC and 100μg SM/ml, and then 2μg/ml of PPD or 10-3/ml of PHA solution were added to these tubes.
It was found that the concentration of PPD of 2μg/ml in culture suspension gave the maximal stimulation for lymphocytes from tuberculin positive donors. The duration of culture was 5 days for PPD-stimulated and 3 days for PHA-stimulated cultures and 0.2μCi of 2-¹⁴C-thymidine was added to those cultures at 4 hours before harvesting of cultures and the harvesting was performed using a modification of the method described by Dutton and Page (1964). The samples were counted in a liquid scintillation counter, and these results were shown as disintegrations per minute after correction for quenting and efficiency. The thymidine uptake after stimulation with PPD and PHA was shown as the subtracted value of the thymidine uptake of unstimulated lymphocytes from that of stimulated lymphocytes.
The thymidine uptake afer stimulation with PPD was studied in the following three groups, and it was 1, 565±2, 541 DPM (mean±S. D.) for pulmonary atypical mycobacteriosis, 5, 231±2, 070 DPM for tuberculosis and 5, 377±2, 487 DPM for healthy donors. Thymidine uptake after stimula tion with PHA was also studied in the above mentioned three groups, and it was 18, 617±12, 276 DPM, 33, 081±9, 385 DPM and 36, 197±5, 658 DPM, respectively.
The value of these thymidine uptake after stimulation both by PPD and PHA in pulmonary atypical mycobacteriosis was significantly lower than that in the other twc groups. Accordingly it could be said that there were general depression of cell-mediated immunity in cases with atypical mycobacteriosis.