Experimental production of pulmonary granulomas: III. Plasma-cell granulomas in mice.

Endobronchial instillation of Freund's complete adjuvant (FCA) induced plasma-cell granulomas in the lungs of DD strain mice. One week after administration, plasma cells appeared in monolayered cell clusters around pulmonary arterioles running along the bronchial tree. The plasma cells increased in number with time to form granulomas consisting mainly of well developed plasma cells with an admixture of lymphocytes and macrophages. At the peak of production of granulomas (4-10 weeks), the plasma cells piled up around the arterioles and infiltrated the connective tissues surrounding the bronchioles. Germinal-centre-like foci could be demonstrated in the granulomas. The lymph nodes draining the treated lobe showed marked proliferation of plasma cells in the medullary cord, suggesting that the plasma cells passed through alveolar walls into the lung and migrated to periarteriolar connective tissue.