Fig. 3.

Effect of Adalimumab therapy on the immune reactivity against M. tuberculosis. (a) PBMNC from eight RA patients and five healthy individuals PPD+ were cultured in the presence or not of a whole protein extract of M. tuberculosis for 72 h in complete medium in 96 well plates. Then, cell proliferation was determined by ³H-TdR incorporation, as described in Materials and Methods. All these experiments were run by triplicate and the results were expressed as the stimulation index. As indicated, dotted, white, and grey bars correspond to RA patients and black and hatched bars to healthy individuals (in the latter case, values correspond to the arithmetic mean and SE, n = 5). (b) A standard PPD skin test (0·1 ml, 5 U) was performed in the same patients and healthy controls PPD+ shown in (a), and the induration diameter was determined at 48 h. This test was performed before (day 0) and at day 180 of Adalimumab therapy, in the case of RA patients. In the case of healthy individuals, values correspond to the arithmetic mean of skin induration at the indicated times.