Stress-induced cholinergic signaling promotes inflammation-associated thrombopoiesis.
To study the role of the stress-induced "readthrough" acetylcholinesterase splice variant, AChE-R, in thrombopoiesis, we used transgenic mice overexpressing human AChE-R (TgR). Increased AChE hydrolytic activity in the peripheral blood of TgR mice was associated with increased thrombopoietin levels and platelet counts. Bone marrow (BM) progenitor cells from TgR mice presented an elevated capacity to produce mixed (GEMM) and megakaryocyte (Mk) colonies, which showed intensified labeling of AChE-R and its interacting proteins RACK1 and PKC. When injected with bacterial lipopolysaccharide (LPS), parent strain FVB/N mice, but not TgR mice, showed reduced platelet counts. Therefore, we primed human CD34+ cells with the synthetic ARP26 peptide, derived from the cleavable C-terminus of AChE-R prior to transplantation, into sublethally irradiated NOD/SCID mice. Engraftment of human cells (both CD45+ and CD41+ Mk) was significantly increased in mice that received ARP26-primed CD34+ human cells versus mice that received fresh nonprimed CD34+ human cells. Moreover, ARP26 induced polyploidization and proplatelet shedding in human MEG-01 promegakaryotic cells, and human platelet engraftment increased following ex vivo expansion of ARP26-treated CD34+ cells as compared to cells expanded with thrombopoietin and stem cell factor. Our findings implicate AChE-R in thrombopoietic recovery, suggesting new therapeutic modalities for supporting platelet production.
Pick
Marjorie
M
Department of Hematology, Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Israel.
Perry
Chava
C
Lapidot
Tsvee
T
Guimaraes-Sternberg
Cinthya
C
Naparstek
Elizabeth
E
Deutsch
Varda
V
Soreq
Hermona
H
D000110:Acetylcholinesterase / Q000096:biosynthesis / Q000235:genetics*; D000818:Animals; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods; D006801:Humans; D008070:Lipopolysaccharides / Q000008:administration & dosage; D008533:Megakaryocytes / Q000166:cytology / Q000378:metabolism; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D008822:Mice, Transgenic; D009154:Mutation; D009479:Neuropeptides / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology; D010976:Platelet Count / Q000379:methods; D012326:RNA Splicing / Q000235:genetics; D000075370:Receptors for Activated C Kinase; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D019089:Stem Cell Factor / Q000097:blood; D034061:Thrombopoiesis / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D013926:Thrombopoietin / Q000097:blood; D014183:Transplantation, Heterologous; D014916:Whole-Body Irradiation
D008070:Lipopolysaccharides; D009479:Neuropeptides; D010455:Peptides; C090294:RACK1 protein, mouse; D000075370:Receptors for Activated C Kinase; D019089:Stem Cell Factor; D013926:Thrombopoietin; D000110:Acetylcholinesterase