MACROPHAGE DEPLETION IN THE RAT AFTER INTRAPERITONEAL ADMINISTRATION OF LIPOSOME-ENCAPSULATED CLODRONATE - DEPLETION KINETICS AND ACCELERATED REPOPULATION OF PERITONEAL AND OMENTAL MACROPHAGES BY ADMINISTRATION OF FREUNDS-ADJUVANT
J. Biewenga et al., MACROPHAGE DEPLETION IN THE RAT AFTER INTRAPERITONEAL ADMINISTRATION OF LIPOSOME-ENCAPSULATED CLODRONATE - DEPLETION KINETICS AND ACCELERATED REPOPULATION OF PERITONEAL AND OMENTAL MACROPHAGES BY ADMINISTRATION OF FREUNDS-ADJUVANT, Cell and tissue research, 280(1), 1995, pp. 189-196
The purpose of this study was to develop a method for the depletion of
macrophages from the peritoneal cavity and the omentum of the rat. Ra
ts received two intraperitoneal injections (at days 0 and 3) with lipo
some-encapsulated clodronate (dichloromethylene bisphosphonate: Cl(2)M
BP-liposomes). This treatment resulted in complete elimination of matu
re tissue macrophages (ED2-positive macrophages) from the peritoneal c
avity and the omentum within 2 days. The elimination included the stro
ngly ED2-positive spindle-shaped cells of the omental membrane. Repopu
lation of the omental ED2-positive macrophages was not seen within the
next 23 days. Whereas ED2-positive macrophages were completely deplet
ed, few ED1-positive cells remained and repopulation of ED1-positive c
ells was faster. The treatment further depleted macrophages from the s
pleen, especially from the red pulp, parathymic lymph nodes and liver.
Freund's incomplete adjuvant administered one day after the last inje
ction of Cl(2)MBP-liposomes considerably accelerated repopulation in t
he omentum. The protocol described might be used to investigate the co
ntribution of mature tissue macrophages to the induction of immune res
ponses, drug metabolism and the elimination of intestinal tumours.