IMMUNOLOGICAL SPECIFICITY OF LYMPHOCYTE CELL-LINES FROM DOGS EXPOSED TO BERYLLIUM-OXIDE

We have reported that dogs exposed twice to aerosols of beryllium oxid e (BeO) developed Be-specific immune responses within the lung, along with granulomatous and fibrotic lung lesions. To evaluate the specific ity of the immune response, lymphocytes from lungs and blood of BeO-ex posed dogs were co-cultured over an irradiated blood monocyte layer, a lternately with interleukin 2 and BeSO4. Resultant cell lines were the n tested for their response to different metal cations, common canine recall antigens, and BeSO4 in an in vitro cell proliferation assay. Th e cell lines responded to BeSO4 in a dose-dependent fashion, with mean stimulation indices of 7, 58, 119, and 112 at concentrations of 0.01, 1.0, 10, and 100 mu M BeSO4 respectively. Cells not proliferate when incubated with ZnSO4 or NiSO4, or with canine distemper, leptospira, a denovirus 2, parvovirus, or parainfluenza antigens. Lymphocytes from n ormal vaccinated dogs proliferated markedly when cultured with these a ntigens. Cells from the cultured cell lines (91%) stained with Thy-1 ( a pan T-cell marker) and 96% stained with DT2 (a helper T-cell marker) . Furthermore, the Be-induced proliferative response was restricted by major histocompatibility (MHC) class II antigens. These data reinforc e the premise that inhalation exposure of dogs to BeO produces lung le sions and MHC class II restricted immunologic responses mediated by Be -specific, helper T-Cells. These data further confirm the hypothesis t hat antigen localized to the lung results in the recruitment of T-cell s to the lung, followed by localized antigen-specific, cell-mediated i mmune responses.