“…Tbe differences in the number of precipitation arcs (2 or more) observed in the sera from some patients, when the double gel-diffusion was performed with intervals of i or 2 years, could be another argument favouring the hypothesis of the presence, in special circumstances, of bronchial secretion antigens in the sera. These findings could be explained by the reabsorption of the sputum admitted by the physiological concept of the expectoration, according to which a certain part of bronchial secretion is absorbed (3,5,9,15). Comprehensive and elucidating studies on this problem were also related by Kohler (10), Yeaguer (18) and Asmundsson & Kilburn (i).…”