Fig. 2

Gel filtration analysis of bronchoalveolar lavage (BAL) fluid from a pulmonary alveolar proteinosis (PAP) patient. An aliquot (250 µl) of BAL from a PAP patient was passed through a Superose 6 gel filtration column. The running buffer was PBS, 5 mM EDTA (pH 7.3). Fractions (1 ml) were analyzed by ELISA to detect SP-A (OD 405). The numbered peaks correspond to the different molecular weight forms of SP-A: 1) hexamers, 2) tetramers, 3) dimers, and 4) apparent single polypeptides. The OD 280 profile shows the elution positions of (A) IgG and (B) albumin.