Mononuclear cells from human lung parenchyma support antigen-induced T lymphocyte proliferation.
We have previously demonstrated that there is a subpopulation of loosely adherent pulmonary mononuclear cells that can be isolated from minced and enzyme-digested lung tissue with a potent capacity to stimulate allogeneic T lymphocyte proliferation. We now demonstrate that these cells are also capable of stimulating an autologous mixed leukocyte reaction (AMLR) and presenting antigen to autologous T lymphocytes. These loosely adherent mononuclear cells (LAM) were more effective than either alveolar macrophages or monocytes as antigen-presenting cells. Depletion of phagocytic or Fc receptor-positive cells from the LAM population enhanced the stimulation of an reaction AMLR while preserving antigen-induced T lymphocyte proliferation. These results indicate that there are nonphagocytic, Fc receptor-negative accessory cells in human lung parenchyma capable of activating resting T cells in an AMLR and supporting antigen-specific T lymphocyte proliferation. The identity of these cells is uncertain, but the data strongly suggest that the cell is not a classical monocyte-derived macrophage. These antigen-presenting cells may be critical in the initiation of immune responses within the lung.
Nicod
L P
LP
Department of Internal Medicine, University of Texas Health Science Center, Dallas.
Lipscomb
M F
MF
Weissler
J C
JC
Toews
G B
GB
D000956:Antigens, Viral / Q000276:immunology; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D002448:Cell Adhesion; D002469:Cell Separation; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000145:classification / Q000276:immunology*; D008168:Lung / Q000276:immunology*; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008264:Macrophages / Q000145:classification / Q000378:metabolism; D009000:Monocytes / Q000276:immunology; D010586:Phagocytes; D010641:Phenotype; D011961:Receptors, Fc; D013601:T-Lymphocytes / Q000276:immunology*; D013745:Tetanus Toxoid / Q000276:immunology
D000956:Antigens, Viral; D011961:Receptors, Fc; D013745:Tetanus Toxoid