Chemical Modification of Interleukin-10 with Mannose 6-Phosphate Groups Yields a Liver-Selective Cytokine

Abstract

ABSTRACT:Cytokines are considered a promising immunotherapy for chronic diseases, because of their potency and fundamental roles in pathological processes. However, their therapeutic use is limited because of their poor pharmacokinetics and pleiotropic effects in various organs. These problems may be overcome by cell-specific delivery of the cytokine. This approach involves chemical modification of the protein with homing devices that recognize receptors on target cells. The cytokine interleukin-10 (IL10) may be valuable as a therapeutic cytokine for patients with liver cirrhosis. However, its rapid renal elimination and general immunosuppressive activities limit therapeutic use. We therefore aim to target this cytokine in the liver, in particular to fibrogenic hepatic stellate cells (HSCs). We show that IL10 is successfully modified with mannose 6-phosphate (M6P), which is a homing device for the mannose 6-phosphate/insulin-like growth factor II (M6P/IGFII) receptor expressed on activated HSCs. Chemical modification did not diminish IL10 efficacy with regard to in vitro anti-inflammatory (lipopolysaccharide-stimulated tumor necrosis factor ␣ release) and antifibrotic (collagen deposition and degradation) activities. Biodistribution studies with radiolabeled M6P-IL10 and IL10 in rats with liver fibrosis showed that modification with M6P groups induced a shift in the distribution from the kidneys (IL10) to the liver (M6P-IL10). Hepatocellular binding of M6P-IL10 occurred via M6P/IGFII receptors and scavenger receptors, indicating that not only HSCs but also Kupffer and endothelial cells are target cells. IL10 did not bind to these receptors. We conclude that we prepared an active and liver-specific form of the cytokine IL10 that can be evaluated for its efficacy to treat liver diseases.

Liver cell-targeted delivery of therapeutic molecules

“…Mannose 6-phosphate (M6P)-modified nanoparticles, such as M6P-HSA (or M6P-HSA-liposome), and N-(2-hydroxypropyl) methacrylamide, which contains M6P and tetrapeptide (GFLG), have been used to target stellate cells (Adrian et al, 2007;Beljaars et al, 2001;Li et al, 2009;van Beuge et al, 2011van Beuge et al, , 2013Yang et al, 2009). However, they are also taken up by Kupffer cells and LSECs because M6P-modified delivery systems can accumulate on the scavenger receptors expressed on these cells (Rachmawati et al, 2007). Administration of polyinosinic acid, an inhibitor of scavenger receptors, was found to inhibit the accumulation of M6P-modified nanoparticles in Kupffer cells and LSECs, but not in stellate cells (Adrian et al, 2007), because stellate cells take up M6P-modified nanoparticles through mannose-6-phosphate/insulin-like growth factor II, receptor-mediated endocytosis (Rachmawati et al, 2007).…”

“…However, they are also taken up by Kupffer cells and LSECs because M6P-modified delivery systems can accumulate on the scavenger receptors expressed on these cells (Rachmawati et al, 2007). Administration of polyinosinic acid, an inhibitor of scavenger receptors, was found to inhibit the accumulation of M6P-modified nanoparticles in Kupffer cells and LSECs, but not in stellate cells (Adrian et al, 2007), because stellate cells take up M6P-modified nanoparticles through mannose-6-phosphate/insulin-like growth factor II, receptor-mediated endocytosis (Rachmawati et al, 2007). Interestingly, HSA terminated with 28 M6P [M6P(28)-HSA] strongly binds to activated stellate cells, but not to quiescent stellate cells (Beljaars et al, 2001).…”

Caveats Regarding the Use of IL-10 and IL-10 Antagonist as Immunotherapeutic Factors

“…Other proposed approaches to target specific tissues are the use of fusion proteins of IL-10 and monoclonal antibodies specific for the targeted cell type, that has been shown to be effective in an experimental model of rheumatoid arthritis [48], and the chemical alteration of IL-10. IL-10 modified with mannose-6 phosphate shows a prevalent homing to the liver, in particular to fibrogenic hepatic stellate cells expressing the mannose 6 phosphate/insulin-like growth factor II receptor, and could be applied to the treatment of cirrhosis [49]. The safety of some of these approaches is still in question, but they hold the promise to allow the targeted deliver of IL-10 into specific tissues or cell types and/or a regulated IL-10 production by the patient, thus reducing the systemic impact of the therapy.…”

Nanoparticles for the treatment of liver fibrosis

“…Both in vitro and in vivo studies in male Wistar rats showed that these NPs were a potent nanocarrier for targeting HSC and can utilize the immune response against fibrosis. [63][64][65] A similar kind of study was done by another group using M6P to modify HSA, which showed successful delivery of DOX, cisplatin and chlorambucil for the pharmacotherapy of liver fibrosis. The reduction in liver fibrosis markers was confirmed using in vitro studies as well as in vivo studies in BDL rats.…”