In vivo administration of lymphocyte-specific monoclonal antibodies in
nonhuman primates: I. Effects of anti-T11 antibodies on the circulating T
cell pool
NL Letvin, J Ritz, LJ Guida, JM Yetz, JM Lambert, EL Reinherz and SF Schlossman
The effects of in vivo administration of three monoclonal antibodies
specific for T11, the E rosette receptor on T lymphocytes, were examined in
the rhesus monkey (Macaca mulatta). These three monoclonal antibodies were
of different isotypes and were shown in in vitro studies to have differing
affinities for the monkey T11 structure. Furthermore, each antibody induced
antigenic modulation of T11 from the cell membrane of the lymphocytes to
varying degrees in vitro. In vivo infusion of each of these antibodies into
normal rhesus monkeys caused remarkably different effects on the
circulating T lymphocyte pool. Infusion of these antibodies at doses of 2
mg/kg caused the coating of circulating T lymphocytes with antibody, the
modulation of T11 off the T cell surface and the transient clearance of T
cells from the circulation. Yet, the variation in the extent to which these
effects were seen with these different antibodies indicates that
extrapolating from studies of the in vivo use of one antibody to the use of
another may be quite difficult. These studies clearly indicate the
strengths of this nonhuman primate system for exploring the uses of
monoclonal antilymphocyte antibodies as therapeutic agents. They, however,
also demonstrate that differences may exist in the affinity of a particular
antibody for homologous lymphocyte surface structures in humans and in a
nonhuman primate species. These differences may make it difficult to
predict the precise effects that the infusion of an antibody will cause in
humans on the basis of alterations it induces in nonhuman primates.
Volume 66,
Issue 4,
pp. 961-966,
10/01/1985
Copyright © 1985 by The American Society of Hematology
