Peptide-directed Suppression of a Pro-inflammatory Cytokine Response

Abstract

Signal-dependent nuclear translocation of transcription factor nuclear factor kappaB (NF-kappaB) is required for the activation of downstream target genes encoding the mediators of immune and inflammatory responses. To inhibit this inducible signaling to the nucleus, we designed a cyclic peptide (cSN50) containing a cell-permeable motif and a cyclized form of the nuclear localization sequence for the p50-NF-kappaB1 subunit of NF-kappaB. When delivered into cultured macrophages treated with the pro-inflammatory agonist lipopolysaccharide, cSN50 was a more efficient inhibitor of NF-kappaB nuclear import than its linear analog. When delivered into mice challenged with lipopolysaccharide, cSN50 potently blocked the production of proinflammatory cytokines (tumor necrosis factor alpha and interferon gamma) and significantly reduced the lethality associated with ensuing endotoxic shock. Based on specificity studies conducted with a mutated form of cSN50, a functional nuclear localization motif is required for this protective effect. Taken together, our findings demonstrate effective targeting of a cell-permeable peptide that attenuates cytokine signaling in vivo. This new class of biological response modifiers may be applicable to the control of systemic inflammatory reactions.

Survival, bacterial clearance and thrombocytopenia are improved in polymicrobial sepsis by targeting nuclear transport shuttles

“…SSHR also serves as a membrane translocating motif (MTM) to enable intracellular delivery of peptides and proteins through an ATP-and endocytosis-independent mechanism [20]. This and other NTMs have been shown to inhibit nuclear translocation of SRTFs [21] and thereby reduce inflammatory responses, microvascular injury, apoptosis and hemorrhagic necrosis with a concomitant gain in survival, in models of lethal shock induced by bacterial toxins [22–24]. …”

Cell-Permeable Parkin Proteins Suppress Parkinson Disease-Associated Phenotypes in Cultured Cells and Animals

“…The persistence of H region sequence variability presumably reflects unknown cargo-specific advantages. Similarly we know that specific MTDs work better than others with specific cargos, particularly with regard to maintaining protein solubility, and have published several such examples [13], [14], [16], [18], [20]–[22], [41]–[43].…”

“…Striking therapeutic benefits using these MTDs have been reported using a small peptide to protect against otherwise lethal inflammatory responses [13], [14], [16], [42] and using larger cell-permeable proteins including suppressor of cytokine signaling 3 (SOCS3) to protect animals against lethal inflammation [18], the NM23 metastasis suppressor to inhibit the seeding and growth of pulmonary metastases [20], the cyclin-dependent kinase inhibitor, p18 INK4c , to inhibit the growth of tumor xenografts [21], the RUNX3 tumor suppressor to suppress the growth of subcutaneous gastric tumor xenografts [22] and the angiogenesis inhibitor, Endostatin, to reduce the growth of human tumor xenografts [43].…”

Antitumor Activity of Cell-Permeable RUNX3 Protein in Gastric Cancer Cells

“…Some success has been achieved using sequences derived from hydrophobic signal peptides to deliver biologically active peptides and proteins to a variety of tissues (including liver, lung, pancreas, and lymphoid tissues). Striking therapeutic benefits have been reported using a small peptide to protect against otherwise lethal inflammatory responses (21, 23– 25). Therapeutic benefits have also been achieved using larger cell-permeable proteins including: (i) suppressor of cytokine signaling 3 (SOCS3) to protect animals against lethal inflammation (22), (ii) the NM23 metastasis suppressor to inhibit the seeding and growth of pulmonary metastases (26), and (iii) the cyclin-dependent kinase inhibitor, p18 INK4c , to inhibit the growth of tumor xenografts (27).…”

“…MITT was used previously to deliver peptides and proteins to a variety of tissues (notably liver, lung, pancreas, and lymphoid tissues), resulting in dramatic protection against lethal inflammatory diseases (21–25), suppression of pulmonary metastases (26), and inhibition of subcutaneous tumor xenografts (27). The technology exploits the ability of hydrophobic macromolecule transduction domains (MTD) to promote bidirectional transfer of peptides and proteins across the plasma membrane (27–29).…”