Enhanced susceptibility to sepsis after simple hemorrhage. Depression of Fc and C3b receptor-mediated phagocytosis
A. Ayala, M. M. Perrin, M. A. Wagner and I. H. Chaudry
Department of Surgery, Michigan State University, East Lansing 48824-1315.
To determine whether phagocytosis mediated by Fc receptors and/or receptors
for the third component of complement (C3b) are altered after hemorrhage,
C3H/HeN mice were subjected to nonlethal hemorrhage and then adequately
resuscitated. Twelve hours after the hemorrhagic episode, a significant
decrease in both Fc (-55.2%) and C3b (-46.6%) receptor-positive peritoneal
macrophages was observed compared with controls. At 24 hours the extent of
the depression, while still marked, was only -22.5% and -17.4% for Fc and
C3b receptors, respectively. By day 3 after hemorrhage, no differences
could be observed for either of these receptors. The capacity of
macrophages from mice after hemorrhage to elaborate interleukin 1 or tumor
necrosis factor-alpha showed no increase over that of the sham controls,
and serum levels of endotoxin were not elevated 2 or 24 hours after
hemorrhage. Moreover, endotoxin-tolerant C3H/HeJ mice also exhibited
depression of both receptors after hemorrhage. Thus, the inability of the
host macrophages to clear opsonized infectious agents after hemorrhage may
be due in part to the loss of Fc and C3b receptors on macrophages.
