B and T cell infiltration in lungs of NZBWF1 mice following cSiO₂ exposure is prevented by dietary supplementation with DHA.

<p>Representative light photomicrographs of lung tissue sections from CON-fed NZBWF1 mice treated with VEH (A, D), CON-fed NZBWF1 mice treated with cSiO₂ (B, E), 2.4% DHA-fed mice treated with cSiO₂ (C, F). Lung sections were stained with either CD45R to identify B-lymphocytes (A-C) or CD3 to identify T cells (D-F) and counterstained with hematoxylin. Inflammatory cell infiltrates in peribronchiolar and perivascular interstitium induced by cSiO₂ (asterisk in B and E) consisted of both B and T lymphocytes as indicated by positive immunohistochemical staining (black arrows in B and E, respectively). B-lymphocytes tended to form distinct aggregates whereas T lymphocytes, which were more diffusely, scattered throughout lymphoid cells aggregates. Dietary DHA blocked B and T cell accumulation in lungs of cSiO₂-treated NZBWF1 mice as evident by marked reduction in CD45R⁺ and CD3⁺ cells. Abbreviations: ba = bronchiolar airway, e = airway epithelium, a = alveolus, v = blood vessel, * = interstitium.