A tandem repeat of a fragment of Listeria monocytogenes internalin B protein induces cell survival and proliferation

Abstract

-Hepatocyte growth factor (HGF) is critical for tissue homeostasis and repair in many organs including the lung, heart, kidney, liver, nervous system, and skin. HGF is a heterodimeric protein containing 20 disulfide bonds distributed among an amino-terminal hairpin, four kringle domains, and a serine protease-like domain. Due to its complex structure, recombinant production of HGF in prokaryotes requires denaturation and refolding, processes that are impractical for large-scale manufacture. Thus, pharmaceutical quantities of HGF are not available despite its potential applications. A fragment of the Listeria monocytogenes internalin B protein from amino acids 36 -321 (InlB 36 -321) was demonstrated to bind to and partially activate the HGF receptor Met. InlB 36 -321 has a stable ␤-sheet structure and is easily produced in its native conformation by Escherichia coli. We cloned InlB 36 -321 (1ϫInlB36-321) and engineered a head-to-tail repeat of InlB 36 -321 with a linker peptide (2ϫInlB36-321); 1ϫInlB36-321 and 2ϫInlB 36 -321 were purified from E. coli. Both 1ϫ and 2ϫInlB36-321 activated the Met tyrosine kinase. We subsequently compared signal transduction of the two proteins in primary lung endothelial cells. 2ϫInlB 36 -321 activated ERK1/2, STAT3, and phosphatidylinositol 3-kinase/Akt pathways, whereas 1ϫInlB 36 -321 activated only STAT3 and ERK1/2. The 2ϫInlB 36 -321 promoted improved motility compared with 1ϫInlB 36 -321 and additionally stimulated proliferation equivalent to full-length HGF. Both the 1ϫ and 2ϫInlB 36 -321 prevented apoptosis by the profibrotic peptide angiotensin II in cell culture and ex vivo lung slice cultures.

Hepatoprotective Activity of InlB321/15, the HGFR Ligand of Bacterial Origin, in CCI4-Induced Acute Liver Injury Mice

“…Using functional HGF analogs is an alternative to HGF-based approaches in regenerative medicine. Recently, we demonstrated that the InlB321/15 protein, which is a HGFR ligand of bacterial origin, accelerates abrasion wound closure [16]. Results obtained in this work demonstrated that the InlB321/15 protein possesses hepatoprotective activity comparable with rhHGF taken in the same concentration.…”

“…Bacterial proteins have comparative advantages over recombinant human growth factors in regard to the accessibility, efficiency, and simplicity of production. Several studies have demonstrated the potential for InlB321 variants derived from different L. monocytogenes strains to stimulate the proliferation and motility of primary lung endothelial cells, keratinocytes, and Human Umblical Vein Endothelial Cells [13,14,15,16,17]. Recently, we showed that the variant InlB321 from L. monocytogenes strain VIMHA015 (InlB321/15) accelerated abrasion wound healing in mice [16].…”

“…Several studies have demonstrated the potential for InlB321 variants derived from different L. monocytogenes strains to stimulate the proliferation and motility of primary lung endothelial cells, keratinocytes, and Human Umblical Vein Endothelial Cells [13,14,15,16,17]. Recently, we showed that the variant InlB321 from L. monocytogenes strain VIMHA015 (InlB321/15) accelerated abrasion wound healing in mice [16]. Here, we demonstrated that InlB321/15 activated the HGFR-dependent MAPK and PI3K/Akt transduction pathways in HepG2 cells and exhibited hepatoprotective activity in the CCl4 induced liver injury mouse model.…”

Pathogenic Biohacking: Induction, Modulation and Subversion of Host Transcriptional Responses by Listeria monocytogenes

“…Similarly, in non-phagocytic cells, InlB is implicated in activating pro-survival signaling via the ERK1/2 kinases and STAT3 transcription factor. Although a precise transcriptional network of InlB signaling is yet to be determined, treating endothelial cells with recombinant InlB has been demonstrated to block the induction of apoptosis in response to angiotensin II, suggesting that these pathways could function to promote host cell survival during infection, thereby maintaining the intracellular niche of Lm [132]. In these instances, whether a transcriptional response is deliberately activated as a means of host manipulation can be difficult distinction to make, and is further complicated by the fact that blocking virulence factor activity often perturbs infection and pathogenesis (i.e., invasion or phagosome escape).…”

Hepatocyte growth factor in physiology and infectious diseases

“…The binding of InlB to Met mimics HGF signaling and induces membrane ruffling and cell scattering via the activation of the PI3-K, which is a process critical for internalization of L. monocytogenes [99]. [103]. They demonstrated that this tandem dimmer induces signaling through ERK1/2, PI3-K/Akt, and STAT3 pathways, and has improved migratory activity.…”