Effect of liposomal interleukin-2 on ascites-forming rat hepatoma.
Interleukin-2 was entrapped in liposomes (Lip-IL-2) and injected into rats. The intraperitoneal injection of Lip-IL-2 into rats bearing an ascites-forming rat hepatoma (AH-66) significantly increased the survival time when compared with rats administered free IL-2 or saline-containing liposomes. The number of peritoneal exudate cells (PEC) increased markedly after intraperitoneal injection of Lip-IL-2 and consisted mainly of macrophages. The level of tumor necrosis factor alpha (TNF-alpha) and the intensity of free radicals increased in the ascites at 48 hrs after Lip-IL-2 administration, whereas TNF-alpha was not detected and the intensity of free radicals did not increase after free IL-2 administration. Our findings suggested that entrapment of IL-2 into liposomes enhanced its potential for cancer therapy, presumably by activating macrophages to produce TNF-alpha and free radicals.
Konno
H
H
Second Department of Surgery, Hamamatsu University School of Medicine, Japan.
Maruo
Y
Y
Matin
A F
AF
Tanaka
T
T
Nakamura
S
S
Baba
S
S
Yamashita
A
A
Tadakuma
T
T
D000818:Animals; D001202:Ascitic Fluid / Q000473:pathology*; D002452:Cell Count; D004337:Drug Carriers; D005122:Exudates and Transudates / Q000166:cytology / Q000378:metabolism; D005609:Free Radicals; D007274:Injections, Intraperitoneal; D007376:Interleukin-2 / Q000008:administration & dosage* / Q000627:therapeutic use; D008081:Liposomes; D008114:Liver Neoplasms, Experimental / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D051381:Rats; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
D004337:Drug Carriers; D005609:Free Radicals; D007376:Interleukin-2; D008081:Liposomes; D014409:Tumor Necrosis Factor-alpha