Journal of Applied Physiology, Vol 45, Issue 6 933-938, Copyright © 1978 by American Physiological Society
Human alveolar macrophages: antigen-independent binding of lymphocytes
L. M. Lussier, D. K. Chandler, A. Sybert and H. Yeager Jr
To characterize the initial step in alveolar macrophage (AM)-lymphocyte (L)
interaction in the human lung, we studied the ability of human AM to bind
autologous blood L in vitro in the absence of antigen. AM were obtained by
saline bronchial lavage through a fiberoptic bronchoscope. Monolayers of AM
attached to glass bound autologous blood L prepared by Ficoll-Hypaque and
nylon wool column separation. The AM-L binding increased from zero time to
a maximum at 2 h and then declined to a zero time value at 18 h. The
binding was dependent on the number of L added to the AM monolayers, with
greatest binding at an AM:L ratio of 1:50. AM:L binding required viability
of AM, but not of L, and was temperature dependent. Pretreatment of AM with
iodoacetic acid, trypsin, neuraminidase, or colchicine diminished
attachment of L at 2 h. Neuraminidase pretreatment of L resulted in
increased binding to nontreated AM. Thus, a physical interaction between
human AM and autologous peripheral blood L can occur in vitro in the
absence of known antigen; similar interaction in vivo may play a role in
the generation of cell-mediated immune responses in the lung.
