Targeted homing of CCR2-overexpressing mesenchymal stromal cells to ischemic brain enhances post-stroke recovery partially through PRDX4-mediated blood-brain barrier preservation

Abstract

Rationale: Mesenchymal stromal cells (MSCs) are emerging as a novel therapeutic strategy for the acute ischemic stroke (AIS). However, the poor targeted migration and low engraftment in ischemic lesions restrict their treatment efficacy. The ischemic brain lesions express a specific chemokine profile, while cultured MSCs lack the set of corresponding receptors. Thus, we hypothesize that overexpression of certain chemokine receptor might help in MSCs homing and improve therapeutic efficacy. Methods: Using the middle cerebral artery occlusion (MCAO) model of ischemic stroke, we identified that CCL2 is one of the most highly expressed chemokines in the ipsilateral hemisphere. Then, we genetically transduced the corresponding receptor, CCR2 to the MSCs and quantified the cell retention of MSCCCR2 compared to the MSCdtomato control. Results: MSCCCR2 exhibited significantly enhanced migration to the ischemic lesions and improved the neurological outcomes. Brain edema and blood-brain barrier (BBB) leakage levels were also found to be much lower in the MSCCCR2-treated rats than the MSCdtomato group. Moreover, this BBB protection led to reduced inflammation infiltration and reactive oxygen species (ROS) generation. Similar results were also confirmed using the in vitro BBB model. Furthermore, genome-wide RNA sequencing (RNA-seq) analysis revealed that peroxiredoxin4 (PRDX4) was highly expressed in MSCs, which mainly contributed to their antioxidant impacts on MCAO rats and oxygen-glucose deprivation (OGD)-treated endothelium. Conclusion: Taken together, this study suggests that overexpression of CCR2 on MSCs enhances their targeted migration to the ischemic hemisphere and improves the therapeutic outcomes, which is attributed to the PRDX4-mediated BBB preservation.

Transplantation of hPSC-derived pericyte-like cells promotes functional recovery in ischemic stroke mice

“…6a). Functional recovery was first assessed by the Menzies score as previously described 32,33 , and greater improvement of the neurological deficits was detected in the hPSC-CNC PC and HBVP groups than in the human dermal fibroblast (HDF) and phosphate-buffered saline (PBS) groups at day 3 post stroke, and no significant difference was found between hPSC-CNC PC group and HBVP group (Fig. 6b).…”

MicroRNA‐182 exacerbates blood‐brain barrier (BBB) disruption by downregulating the mTOR/FOXO1 pathway in cerebral ischemia

“…The pMCAO-miR-182 KD group had significantly attenuated the extravasation of Evans blue compared with the pMCAO-WT group ( Figure 2B). Because astrocyte end-feet and endothelial cells TJ proteins are essential for the maintenance of BBB homeostasis, 35,36 we examined the structural integrity of the BBB through double-staining of endothelial cells and astrocytes. The results showed that the BBB structure was relatively complete in the sham group, while the pMCAO-miR-182 KD group had more BBB structures in the infarction area compared with the pMCAO-WT group ( Figure 2C).…”

Enhancing the Therapeutic Potential of CCL2-Overexpressing Mesenchymal Stem Cells in Acute Stroke

“…CCL2 is constitutively present in the normal brain and within neurons, astrocytes, and endothelial cells; however, it is upregulated during a stroke [ 17 , 18 , 19 ]. Increases in CCL2 level induce the recruitment of various inflammatory cells to the brain and disruption of the BBB after stroke [ 10 , 20 ]. This migration of inflammatory cells is promoted by CCL2/CCR2 interactions, which induces translocation of CCR2-expressing inflammatory cells into infarct areas already experiencing increased CCL2 expression following a stroke.…”

“…Previously studies suggest that increased CCL2 levels in stroke exacerbate neuro-inflammation and subsequent brain injury, thereby increasing stroke volume and resulting in poor prognosis [ 21 , 22 ]. However, recent studies show that CCL2/CCR2 interaction positively affects functional recovery from stroke [ 23 , 24 ], and other studies confirm that CCL2 promotes the homing of CCR2-expressing stem cells from the bone marrow to the damaged brain, which contributes to brain repair following stroke [ 20 , 25 , 26 ]. Additionally, this interaction promotes intravascular migration of stem cells into the injury sites and is essential for the therapeutic homing of CCR2-expressing stem cells [ 6 , 7 , 11 , 27 , 28 , 29 ].…”

“…Additionally, this interaction promotes intravascular migration of stem cells into the injury sites and is essential for the therapeutic homing of CCR2-expressing stem cells [ 6 , 7 , 11 , 27 , 28 , 29 ]. Furthermore, studies indicate that CCR2 overexpression on MSCs [ 20 ] or exosomes [ 26 ] following genetic modification enhances their targeted migration to the ischemic hemisphere and improves therapeutic outcomes.…”