[A fatal case of farmer's lung: a study of specific classes of antibodies in the serum and broncho-alveolar lavage]. / Un cas mortel de maladie de poumon du fermier: étude des classes d'anticorps spécifiques dans le sérum et le lavage broncho-alvéolaire.

A 61 year old agricultural worker, without any respiratory past history, presented with a pulmonary fibrosis of rapid and fatal outcome. This was due to an extrinsic allergic fibrosing alveolitis of the Farmer's lung type. A search for precipitins "vis-à-vis" Micropolyspora faeni was strongly positive in the serum and broncho-alveolar lavage. Specific IgA antibodies to M. faeni, as well as specific antigenic fractions of M. faeni were demonstrated in the broncho-alveolar lavage. This IgA was almost certainly produced locally.

[Circulating immune complexes and bronchopulmonary cancers]. / Complexes immuns circulants et cancers broncho-pulmonaires.

This study of circulating immune complexes was carried out using a C1q radio-labelled complement fixation test in 162 patients suffering from broncho-pulmonary disease. There were a similar number of positive results in primary cancer (44%) or secondary (53%) in tuberculosis (37%) or other pathologies (64%). With primary causes neither the histological type nor the stage of extension were associated with any particular frequency of positive tests. The diagnostic interest of research into circulating immune complexes thus appears limited. This study shows however, the activation of humoral systems of immunity during the course of broncho-pulmonary diseases, and raises the prospect of qualitative studies into the nature of the antigen implicated and their role in the mechanism of defence of the organism.