Cell surface glycan engineering of neural stem cells augments neurotropism and improves recovery in a murine model of multiple sclerosis

Abstract

Neural stem cell (NSC)-based therapies offer potential for neural repair in central nervous system (CNS) inflammatory and degenerative disorders. Typically, these conditions present with multifocal CNS lesions making it impractical to inject NSCs locally, thus mandating optimization of vascular delivery of the cells to involved sites. Here, we analyzed NSCs for expression of molecular effectors of cell migration and found that these cells are natively devoid of E-selectin ligands. Using glycosyltransferase-programmed stereosubstitution (GPS), we glycan engineered the cell surface of NSCs ("GPS-NSCs") with resultant enforced expression of the potent E-selectin ligand HCELL (hematopoietic cell E-/L-selectin ligand) and of an E-selectin-binding glycoform of neural cell adhesion molecule ("NCAM-E"). Following intravenous (i.v.) injection, short-term homing studies demonstrated that, compared with buffer-treated (control) NSCs, GPS-NSCs showed greater neurotropism. Administration of GPS-NSC significantly attenuated the clinical course of experimental autoimmune encephalomyelitis (EAE), with markedly decreased inflammation and improved oligodendroglial and axonal integrity, but without evidence of long-term stem cell engraftment. Notably, this effect of NSC is not a universal property of adult stem cells, as administration of GPS-engineered mouse hematopoietic stem/progenitor cells did not improve EAE clinical course. These findings highlight the utility of cell surface glycan engineering to boost stem cell delivery in neuroinflammatory conditions and indicate that, despite the use of a neural tissue-specific progenitor cell population, neural repair in EAE results from endogenous repair and not from direct, NSC-derived cell replacement.

Not just a marker: CD34 on human hematopoietic stem/progenitor cells dominates vascular selectin binding along with CD44

“…13 These results also elicit the question of whether the appropriate glycosyltransferases/glycosidases and/or appropriate substrates for these enzymes are differentially expressed in these subpopulations of HSPCs. Such an understanding of this valuable population of cells will allow researchers to harness technologies 34,[54][55][56][57] that improve the migration capacity of these cells with the ultimate goal of using these cells in clinical settings.…”

Quantitative Characterization of E-selectin Interaction with Native CD44 and P-selectin Glycoprotein Ligand-1 (PSGL-1) Using a Real Time Immunoprecipitation-based Binding Assay

“…We demonstrate through several examples the quantitative nature of our SPR-based IP approach, including the ability to 1) capture residual and transient interactions, 2) directly characterize the contribution of different post-translational modifications on ligands (that contribute particular isoforms of proteins) to the unique antigenic efficiencies of the antibody used for IP, and 3) determine binding constants of antibody-isolated ligands with the adhesion molecule of interest, E-selectin. This assay enabled a comparative and comprehensive binding analysis of CD44/hematopoietic cell E-/L-selectin ligand (HCELL) and P-selectin glycoprotein ligand-1 (PSGL-1) (11)(12)(13)(14)(15)53) in their native forms from KG1a cells with E-selectin. In addition, we include a comprehensive analysis of CD44/HCELL binding with E-selectin of two additional leukemic cell lines, THP-1 and HL-60.…”

Intranasal delivery of stem cell-based therapies for the treatment of brain malignancies

“…Several studies have shown that stem-cell tumor-tropism occurs along a chemotactic gradient, and several soluble factor receptors have been identified that influence stem-cell migration in a tumor model [26–30]. Additionally, there is evidence that the stem-cell interactions with astrocytes, neurons, and the extracellular matrix (ECM) could affect stem-cell migration following IND [31–34]. Although this review does not intend to cover the complexity of all migratory mechanisms utilized by stem cells in the brain, we highlight several of them in the section below.…”

“…Stem cells interact with vascular endothelial cells as they travel through circulation, with a loose adhesion to selectins and glycoproteins resembling that of disseminated lymphocytes [31]. Furthermore, like other tissue-homing cells, stem cells rely on interactions between cellular adhesion molecules to arrest on the surface of endothelial cells.…”

“…IND of stem-cell-based therapeutics takes advantage of stem cells’ natural tropism toward glioma and their capacity to administer multiple therapeutic modalities in a repeatable and minimally invasive course. Once the modality is fully understood, it may be used in the treatment of different brain malignancies or other brain disorders [2,15,31,124–126]. …”