RESTRICTED EXPRESSION OF GALACTOSE N-ACETYLGALACTOSAMINE-SPECIFIC MACROPHAGE C-TYPE LECTIN TO CONNECTIVE-TISSUE AND TO METASTATIC LESIONS IN MOUSE LUNG/
Y. Imai et al., RESTRICTED EXPRESSION OF GALACTOSE N-ACETYLGALACTOSAMINE-SPECIFIC MACROPHAGE C-TYPE LECTIN TO CONNECTIVE-TISSUE AND TO METASTATIC LESIONS IN MOUSE LUNG/, Immunology, 86(4), 1995, pp. 591-598
We investigated expression of macrophage galactose/N-acetylgalactosami
ne-specific C-type lectin (MMGL) in normal mouse lung tissue and in lu
ngs with metastatic nodules produced by OV2944-HM-1 mouse metastatic o
varian tumour cells. Cells expressing MMGL were detected in tissue sec
tions using a rat monoclonal antibody (mAb) specific for MMGL, mAb LOM
-14. The regions containing cells immunostained using mAb LOM-14 were
restricted to the connective tissue surrounding blood vessels and resp
iratory epithelia, whereas alveolar regions of lung parenchyma were es
sentially devoid of these cells. In contrast, a significant number of
cells in the alveolar regions was shown to express Mac-1 antigen (CD11
b/CD18) and leucocyte common antigen (CD45). Immunoelectron microscopi
c study revealed the presence of MMGL in the intracellular vesicles of
cells residing in connective tissue. In the tumour-bearing mice, MMGL
-positive cells were also present within metastatic nodules. Their loc
alization outside of the nodules was restricted to connective tissue.
Cells with Mac-1 antigens were seen both in the nodules and in the alv
eolar regions. These results indicate that MMGL serves as a unique mac
rophage marker in mouse lung tissue due to its topographical site-depe
ndent pattern of expression. The present results also suggest a possib
le involvement of macrophages expressing MMGL in the immune response d
irected against metastatic tumour cells.