Erythropoietin Pretreatment of Transplanted Endothelial Colony-Forming Cells Enhances Recovery in a Cerebral Ischemia Model by Increasing Their Homing Ability: A SPECT/CT Study

Kidney disease and stroke: epidemiology and potential mechanisms of susceptibility

Patients with chronic kidney disease (CKD) have an increased risk of both ischaemic and haemorrhagic stroke compared with the general population. Both acute and chronic kidney impairment are independently associated with poor outcome after the onset of a stroke, after adjustment for confounders. End-stage kidney disease (ESKD) is associated with a 7- and 9-fold increased incidence of both ischaemic and haemorrhagic strokes, respectively, poorer neurological outcome and a 3-fold higher mortality. Acute kidney injury (AKI) occurs in 12% of patients with stroke and is associated with a 4-fold increased mortality and unfavourable functional outcome. CKD patients seem to have less access to revascularisation techniques like thrombolysis and thrombectomy despite their poorer prognosis. Even if CKD patients could benefit from these specific treatments in acute ischaemic stroke, their prognosis remains poor. After thrombolysis, CKD is associated with a 40% increased risk of intracerebral haemorrhage (ICH), a 20% increase in mortality and poorer functional neurological outcomes. After thrombectomy, CKD is not associated with ICH but is still associated with increased mortality, and AKI with unfavourable outcome and mortality. The beneficial impact of gliflozins on the prevention of stroke is still uncertain. Non-traditional risk factors of stroke, like uraemic toxins, can lead to chronic cerebrovascular disease predisposing to stroke in CKD, notably through an increase in the blood-brain barrier permeability and impaired coagulation and thrombosis mechanisms. Preclinical and clinical studies are needed to specifically assess the impact of these non-traditional risk factors on stroke incidence and outcomes, aiming to optimize and identify potential therapeutic targets.

Unraveling the potential of endothelial progenitor cells as a treatment following ischemic stroke

Ischemic stroke is becoming one of the most common causes of death and disability in developed countries. Since current therapeutic options are quite limited, focused on acute reperfusion therapies that are hampered by a very narrow therapeutic time window, it is essential to discover novel treatments that not only stop the progression of the ischemic cascade during the acute phase, but also improve the recovery of stroke patients during the sub-acute or chronic phase. In this regard, several studies have shown that endothelial progenitor cells (EPCs) can repair damaged vessels as well as generate new ones following cerebrovascular damage. EPCs are circulating cells with characteristics of both endothelial cells and adult stem cells presenting the ability to differentiate into mature endothelial cells and self-renew, respectively. Moreover, EPCs have the advantage of being already present in healthy conditions as circulating cells that participate in the maintenance of the endothelium in a direct and paracrine way. In this scenario, EPCs appear as a promising target to tackle stroke by self-promoting re-endothelization, angiogenesis and vasculogenesis. Based on clinical data showing a better neurological and functional outcome in ischemic stroke patients with higher levels of circulating EPCs, novel and promising therapeutic approaches would be pharmacological treatment promoting EPCs-generation as well as EPCs-based therapies. Here, we will review the latest advances in preclinical as well as clinical research on EPCs application following stroke, not only as a single treatment but also in combination with new therapeutic approaches.

Bioactive extracellular vesicles from a subset of endothelial progenitor cells rescue retinal ischemia and neurodegeneration

Disruption of the neurovascular unit (NVU) underlies the pathophysiology of various CNS diseases. One strategy to repair NVU dysfunction uses stem/progenitor cells to provide trophic support to the NVU's functionally coupled and interdependent vasculature and surrounding CNS parenchyma. A subset of endothelial progenitor cells, endothelial colony-forming cells (ECFCs) with high expression of the CD44 hyaluronan receptor (CD44hi), provides such neurovasculotrophic support via a paracrine mechanism. Here, we report that bioactive extracellular vesicles from CD44hi ECFCs (EVshi) are paracrine mediators, recapitulating the effects of intact cell therapy in murine models of ischemic/neurodegenerative retinopathy; vesicles from ECFCs with low expression levels of CD44 (EVslo) were ineffective. Small RNA sequencing comparing the microRNA cargo from EVshi and EVslo identified candidate microRNAs that contribute to these effects. EVshi may be used to repair NVU dysfunction through multiple mechanisms to stabilize hypoxic vasculature, promote vascular growth, and support neural cells.

Tracking Radiolabeled Endothelial Microvesicles Predicts Their Therapeutic Efficacy: A Proof-of-Concept Study in Peripheral Ischemia Mouse Model Using SPECT/CT Imaging

Microvesicles, so-called endothelial large extracellular vesicles (LEVs), are of great interest as biological markers and cell-free biotherapies in cardiovascular and oncologic diseases. However, their therapeutic perspectives remain limited due to the lack of reliable data regarding their systemic biodistribution after intravenous administration. Methods: Applied to a mouse model of peripheral ischemia, radiolabeled endothelial LEVs were tracked and their in vivo whole-body distribution was quantified by microSPECT/CT imaging. Hindlimb perfusion was followed by LASER Doppler and motility impairment function was evaluated up to day 28 post-ischemia. Results: Early and specific homing of LEVs to ischemic hind limbs was quantified on the day of ischemia and positively correlated with reperfusion intensity at a later stage on day 28 after ischemia, associated with an improved motility function. Conclusions: This concept is a major asset for investigating the biodistribution of LEVs issued from other cell types, including cancer, thus partly contributing to better knowledge and understanding of their fate after injection.

Long-term administration of resveratrol at low doses improves neurocognitive performance as well as cerebral blood flow and modulates the inflammatory pathways in the brain

There is an increasing prevalence of coincident cerebrovascular deficiency and cognitive dysfunction with aging. Increased oxidative stress as well as inflammation that occurs with aging are associated with the impairment of cerebral vascularization. Interestingly, Resveratrol (RSV), a natural phytoalexin, is known to be a strong antioxidant and possesses anti-inflammatory properties. Collectively, these observations strongly suggest that RSV could protect against cerebral vascularization defect and then improves the decline cognitive function associated with aging. In order to test this hypothesis, we investigated the effect of a long-term RSV treatment (1.25 mg/day for 5 months) on cognitive performances of animals that we have allowed to age normally. Then, we further analyzed the gene expression profile and the cerebral blood flow in the brain. By means of novel object recognition (NOR) test, we observed that RSV enhanced NOR performances of aged rats. In addition, RSV enhanced cerebral blood flow during NOR task in aged rats. Using microarrays experiments, we also showed that several pathways related to inflammation and oxidative stress (Eicosanoid signaling, MIF-mediated innate immunity, NF-kB signaling, TNFR2 signaling, IL6 signaling, Production of nitric oxide and ROS) were down-regulated in the brain of RSV treatments rats compared to control rats. In conclusion, these results support that a long-term treatment with RSV improves cognitive performance in the elderly male rat model. This effect is associated with an increase in cerebral blood flow and a decrease in the expression of several pro-inflammatory pathways in the brain.

EPO and EPO-Receptor System as Potential Actionable Mechanism for the Protection of Brain and Heart in Refractory Epilepsy and SUDEP

The most important activity of erythropoietin (EPO) is the regulation of erythrocyte production by activation of the erythropoietin receptor (EPO-R), which triggers the activation of anti-apoptotic and proliferative responses of erythroid progenitor cells. Additionally, to erythropoietic EPO activity, an antiapoptotic effect has been described in a wide spectrum of tissues. EPO low levels are found in the central nervous system (CNS), while EPO-R is expressed in most CNS cell types. In spite of EPO-R high levels expressed during the hypoxicischemic brain, insufficient production of endogenous cerebral EPO could be the cause of determined circuit alterations that lead to the loss of specific neuronal populations. In the heart, high EPO-R expression in cardiac progenitor cells appears to contribute to myocardial regeneration under EPO stimulation. Several lines of evidence have linked EPO to an antiapoptotic role in CNS and in heart tissue. In this review, an antiapoptotic role of EPO/EPO-R system in both brain and heart under hypoxic conditions, such as epilepsy and sudden death (SUDEP) has been resumed. Additionally, their protective effects could be a new field of research and a novel therapeutic strategy for the early treatment of these conditions and avoid SUDEP.

Therapeutic Potential of Endothelial Colony-Forming Cells in Ischemic Disease: Strategies to Improve their Regenerative Efficacy

Cardiovascular disease (CVD) comprises a range of major clinical cardiac and circulatory diseases, which produce immense health and economic burdens worldwide. Currently, vascular regenerative surgery represents the most employed therapeutic option to treat ischemic disorders, even though not all the patients are amenable to surgical revascularization. Therefore, more efficient therapeutic approaches are urgently required to promote neovascularization. Therapeutic angiogenesis represents an emerging strategy that aims at reconstructing the damaged vascular network by stimulating local angiogenesis and/or promoting de novo blood vessel formation according to a process known as vasculogenesis. In turn, circulating endothelial colony-forming cells (ECFCs) represent truly endothelial precursors, which display high clonogenic potential and have the documented ability to originate de novo blood vessels in vivo. Therefore, ECFCs are regarded as the most promising cellular candidate to promote therapeutic angiogenesis in patients suffering from CVD. The current briefly summarizes the available information about the origin and characterization of ECFCs and then widely illustrates the preclinical studies that assessed their regenerative efficacy in a variety of ischemic disorders, including acute myocardial infarction, peripheral artery disease, ischemic brain disease, and retinopathy. Then, we describe the most common pharmacological, genetic, and epigenetic strategies employed to enhance the vasoreparative potential of autologous ECFCs by manipulating crucial pro-angiogenic signaling pathways, e.g., extracellular-signal regulated kinase/Akt, phosphoinositide 3-kinase, and Ca²⁺ signaling. We conclude by discussing the possibility of targeting circulating ECFCs to rescue their dysfunctional phenotype and promote neovascularization in the presence of CVD.

NOX4 is a major regulator of cord blood-derived endothelial colony-forming cells which promotes post-ischaemic revascularization

AIMS

Cord blood-derived endothelial colony-forming cells (CB-ECFCs) are a defined progenitor population with established roles in vascular homeostasis and angiogenesis, which possess low immunogenicity and high potential for allogeneic therapy and are highly sensitive to regulation by reactive oxygen species (ROS). The aim of this study was to define the precise role of the major ROS-producing enzyme, NOX4 NADPH oxidase, in CB-ECFC vasoreparative function.

METHODS AND RESULTS

In vitro CB-ECFC migration (scratch-wound assay) and tubulogenesis (tube length, branch number) was enhanced by phorbol 12-myristate 13-acetate (PMA)-induced superoxide in a NOX-dependent manner. CB-ECFCs highly-expressed NOX4, which was further induced by PMA, whilst NOX4 siRNA and plasmid overexpression reduced and potentiated in vitro function, respectively. Increased ROS generation in NOX4-overexpressing CB-ECFCs (DCF fluorescence, flow cytometry) was specifically reduced by superoxide dismutase, highlighting induction of ROS-specific signalling. Laser Doppler imaging of mouse ischaemic hindlimbs at 7 days indicated that NOX4-knockdown CB-ECFCs inhibited blood flow recovery, which was enhanced by NOX4-overexpressing CB-ECFCs. Tissue analysis at 14 days revealed consistent alterations in vascular density (lectin expression) and eNOS protein despite clearance of injected CB-ECFCs, suggesting NOX4-mediated modulation of host tissue. Indeed, proteome array analysis indicated that NOX4-knockdown CB-ECFCs largely suppressed tissue angiogenesis, whilst NOX4-overexpressing CB-ECFCs up-regulated a number of pro-angiogenic factors specifically-linked with eNOS signalling, in parallel with equivalent modulation of NOX-dependent ROS generation, suggesting that CB-ECFC NOX4 signalling may promote host vascular repair.

CONCLUSION

Taken together, these findings indicate a key role for NOX4 in CB-ECFCs, thereby highlighting its potential as a target for enhancing their reparative function through therapeutic priming to support creation of a pro-reparative microenvironment and effective post-ischaemic revascularization.

Human endothelial colony-forming cells in regenerative therapy: A systematic review of controlled preclinical animal studies

Endothelial colony‐forming cells (ECFCs) hold significant promise as candidates for regenerative therapy of vascular injury. Existing studies remain largely preclinical and exhibit marked design heterogeneity. A systematic review of controlled preclinical trials of human ECFCs is needed to guide future study design and to accelerate clinical translation. A systematic search of Medline and EMBASE on 1 April 2019 returned 3131 unique entries of which 66 fulfilled the inclusion criteria. Most studies used ECFCs derived from umbilical cord or adult peripheral blood. Studies used genetically modified immunodeficient mice (n = 52) and/or rats (n = 16). ECFC phenotypes were inconsistently characterized. While >90% of studies used CD31+ and CD45−, CD14− was demonstrated in 73% of studies, CD146+ in 42%, and CD10+ in 35%. Most disease models invoked ischemia. Peripheral vascular ischemia (n = 29), central nervous system ischemia (n = 14), connective tissue injury (n = 10), and cardiovascular ischemia and reperfusion injury (n = 7) were studied most commonly. Studies showed predominantly positive results; only 13 studies reported ≥1 outcome with null results, three reported only null results, and one reported harm. Quality assessment with SYRCLE revealed potential sources of bias in most studies. Preclinical ECFC studies are associated with benefit across several ischemic conditions in animal models, although combining results is limited by marked heterogeneity in study design. In particular, characterization of ECFCs varied and aspects of reporting introduced risk of bias in most studies. More studies with greater focus on standardized cell characterization and consistency of the disease model are needed.

Endothelial TRPV1 as an Emerging Molecular Target to Promote Therapeutic Angiogenesis

Therapeutic angiogenesis represents an emerging strategy to treat ischemic diseases by stimulating blood vessel growth to rescue local blood perfusion. Therefore, injured microvasculature may be repaired by stimulating resident endothelial cells or circulating endothelial colony forming cells (ECFCs) or by autologous cell-based therapy. Endothelial Ca²⁺ signals represent a crucial player in angiogenesis and vasculogenesis; indeed, several angiogenic stimuli induce neovessel formation through an increase in intracellular Ca²⁺ concentration. Several members of the Transient Receptor Potential (TRP) channel superfamily are expressed and mediate Ca²⁺-dependent functions in vascular endothelial cells and in ECFCs, the only known truly endothelial precursor. TRP Vanilloid 1 (TRPV1), a polymodal cation channel, is emerging as an important player in endothelial cell migration, proliferation, and tubulogenesis, through the integration of several chemical stimuli. Herein, we first summarize TRPV1 structure and gating mechanisms. Next, we illustrate the physiological roles of TRPV1 in vascular endothelium, focusing our attention on how endothelial TRPV1 promotes angiogenesis. In particular, we describe a recent strategy to stimulate TRPV1-mediated pro-angiogenic activity in ECFCs, in the presence of a photosensitive conjugated polymer. Taken together, these observations suggest that TRPV1 represents a useful target in the treatment of ischemic diseases.

Therapeutic Potential of Endothelial Colony Forming Cells Derived from Human Umbilical Cord Blood

Endothelial progenitor cells (EPCs) are implicated in multiple biologic processes such as vascular homeostasis, neovascularization and tissue regeneration, and tumor angiogenesis. A subtype of EPCs is referred to as endothelial colony-forming cells (ECFCs), which display robust clonal proliferative potential and can form durable and functional blood vessels in animal models. In this review, we provide a brief overview of EPCs' characteristics, classification and origins, a summary of the progress in preclinical studies with regard to the therapeutic potential of human umbilical cord blood derived ECFCs (CB-ECFCs) for ischemia repair, tissue engineering and tumor, and highlight the necessity to select high proliferative CB-ECFCs and to optimize their recovery and expansion conditions.

Erythropoietin attenuates propofol-induced hippocampal neuronal cell injury in developing rats by inhibiting toll-like receptor 4 expression

BACKGROUND

This study was to investigate the neuroprotective effect of erythropoietin (EPO) on hippocampal neuronal cell injury in developing rats.

METHODS

The hippocampal neurons cells were obtained from SD rats aged 10 days and divided into control, propofol, EPO, and propofol + erythropoietin (E + P) groups. Cell proliferation and apoptosis were measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), Ki-67 immunofluorescence, and flow cytometry, respectively. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-4 and IL-10 were detected by enzyme-linked immunosorbent assay (ELISA). Cellular immunohistochemistry was utilized to detect the expression of proliferating cell nuclear antigen (PCNA), nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3). Quantitative real time polymerase chain reaction (qRT-PCR) and western blot were used to detect the expression of Bax, Bcl-2, Caspase-3, toll-like receptor 4 (TLR4) and p65. Furthermore, TLR4 antagonist (TAK-242) and activator (LPS) were used to study the relationship between EPO and TLR4.

RESULTS

Propofol treatment caused morphological and structural damage of hippocampal neurons. However, EPO significantly improved this damage, enhanced cell proliferation, decreased apoptosis and pro-inflammatory factor content, up-regulated the expression of Ki-67, PCNA, Bcl-2, NGF, BDNF and NT-3, as well as decreased the expression of Bax, Caspase-3, TLR4 and p65 (p < 0.05). After TAK-242 or LPS treatment, it showed similar results in propofol + TAK-242 (T + P) group and E + P group.

CONCLUSION

Erythropoietin could attenuate propofol-induced hippocampal neuronal cell injury in developing rats, which may be related to inhibit TLR4 expression.

The vasoreparative potential of endothelial colony-forming cells in the ischemic retina is enhanced by cibinetide, a non-hematopoietic erythropoietin mimetic

PURPOSE

Retinal ischemia remains a common sight threatening end-point in blinding diseases such as diabetic retinopathy and retinopathy of prematurity. Endothelial colony forming cells (ECFCs) represent a subpopulation of endothelial progenitors with therapeutic utility for promoting reparative angiogenesis in the ischaemic retina. The current study has investigated the potential of enhancing this cell therapy approach by the dampening of the pro-inflammatory milieu typical of ischemic retina. Based on recent findings that ARA290 (cibinetide), a peptide based on the Helix-B domain of erythropoietin (EPO), is anti-inflammatory and tissue-protective, the effect of this peptide on ECFC-mediated vascular regeneration was studied in the ischemic retina.

METHODS

The effects of ARA290 on pro-survival signaling and function were assessed in ECFC cultures in vitro. Efficacy of ECFC transplantation therapy to promote retinal vascular repair in the presence and absence of ARA290 was studied in the oxygen induced retinopathy (OIR) model of retinal ischemia. The inflammatory cytokine profile and microglial activation were studied as readouts of inflammation.

RESULTS

ARA290 activated pro-survival signaling and enhanced cell viability in response to H₂O₂-mediated oxidative stress in ECFCs in vitro. Preconditioning of ECFCs with EPO or ARA290 prior to delivery to the ischemic retina did not enhance vasoreparative function. ARA290 delivered systemically to OIR mice reduced pro-inflammatory expression of IL-1β and TNF-α in the mouse retina. Following intravitreal transplantation, ECFCs incorporated into the damaged retinal vasculature and significantly reduced avascular area. The vasoreparative function of ECFCs was enhanced in the presence of ARA290 but not EPO.

DISCUSSION

Regulation of the pro-inflammatory milieu of the ischemic retina can be enhanced by ARA290 and may be a useful adjunct to ECFC-based cell therapy for ischemic retinopathies.

Recent Advances in Endothelial Progenitor Cells Toward Their Use in Clinical Translation

Since the discovery of Endothelial Progenitor Cells (EPC) by Asahara and colleagues in 1997, an increasing number of preclinical studies have shown that EPC based therapy is feasible, safe, and efficacious in multiple disease states. Subsequently, this has led to several, mainly early phase, clinical trials demonstrating the feasibility and safety profile of EPC therapy, with the suggestion of efficacy in several conditions including ischemic heart disease, pulmonary arterial hypertension and decompensated liver cirrhosis. Despite the use of the common term “EPC,” the characteristics, manufacturing methods and subset of the cell type used in these studies often vary significantly, rendering clinical translation challenging. It has recently been acknowledged that the true EPC is the endothelial colony forming cells (ECFC). The objective of this review was to summarize and critically appraise the registered and published clinical studies using the term “EPC,” which encompasses a heterogeneous cell population, as a therapeutic agent. Furthermore, the preclinical data using ECFC from the PubMed and Web of Science databases were searched and analyzed. We noted that despite the promising effect of ECFC on vascular regeneration, no clinical study has stemmed from these preclinical studies. We showed that there is a lack of information registered on www.clinicaltrials.gov for EPC clinical trials, specifically on cell culture methods. We also highlighted the importance of a detailed definition of the cell type used in EPC clinical trials to facilitate comparisons between trials and better understanding of the potential clinical benefit of EPC based therapy. We concluded our review by discussing the potential and limitations of EPC based therapy in clinical settings.

The Vasoreparative Potential of Endothelial Colony Forming Cells: A Journey Through Pre-clinical Studies

For over a decade various cell populations have been investigated for their vasoreparative potential. Cells with the capacity to promote blood vessel regeneration are commonly known as endothelial progenitor cells (EPCs); although such a definition is currently considered too simple for the complexity of cell populations involved in the reparative angiogenic process. A subset of EPCs called endothelial colony forming cells (ECFCs) have emerged as a suitable candidate for cytotherapy, primarily due to their clonogenic progenitor characteristics, unequivocal endothelial phenotype, and inherent ability to promote vasculogenesis. ECFCs can be readily isolated from human peripheral and cord blood, expanded ex vivo and used to revascularize ischemic tissues. These cells have demonstrated efficacy in several in vivo preclinical models such as the ischemic heart, retina, brain, limb, lung and kidney. This review will summarize the current pre-clinical evidence for ECFC cytotherapy and discuss their potential for clinical application.

Warming Up to New Possibilities with the Capsaicin Receptor TRPV1: mTOR, AMPK, and Erythropoietin

BACKGROUND

Transient receptor potential (TRP) channels are a superfamily of ion channels termed after the trp gene in Drosophila that are diverse in structure and control a wide range of biological functions including cell development and growth, thermal regulation, and vascular physiology. Of significant interest is the transient receptor potential cation channel subfamily V member 1 (TRPV1) receptor, also known as the capsaicin receptor and the vanilloid receptor 1, that is a non-selective cation channel sensitive to a host of external stimuli including capsaicin and camphor, venoms, acid/basic pH changes, and temperature.

METHODS

Given the multiple modalities that TRPV1 receptors impact in the body, we examined and discussed the role of these receptors in vasomotor control, metabolic disorders, cellular injury, oxidative stress, apoptosis, autophagy, and neurodegenerative disorders and their overlap with other signal transduction pathways that impact trophic factors.

RESULTS

Surprisingly, TRPV1 receptors do not rely entirely upon calcium signaling to affect cellular biology, but also have a close relationship with the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), and protein kinase B (Akt) that have roles in pain sensitivity, stem cell development, cellular survival, and cellular metabolism. These pathways with TRPV1 converge in the signaling of growth factors with recent work highlighting a relationship with erythropoietin (EPO). Angiogenesis and endothelial tube formation controlled by EPO requires, in part, the activation of TRPV1 receptors in conjunction with Akt and AMPK pathways.

CONCLUSION

TRPV1 receptors could prove to become vital to target disorders of vascular origin and neurodegeneration. Broader and currently unrealized implementations for both EPO and TRPV1 receptors can be envisioned for for the development of novel therapeutic strategies in multiple systems of the body.

Tissue regeneration using endothelial colony-forming cells: promising cells for vascular repair

Repairing and rebuilding damaged tissue in diseased human subjects remains a daunting challenge for clinical medicine. Proper vascular formation that serves to deliver blood-borne nutrients and adequate levels of oxygen and to remove wastes is critical for successful tissue regeneration. Endothelial colony-forming cells (ECFC) represent a promising cell source for revascularization of damaged tissue. ECFCs are identified by displaying a hierarchy of clonal proliferative potential and by pronounced postnatal vascularization ability in vivo. In this review, we provide a brief overview of human ECFC isolation and characterization, a survey of a number of animal models of human disease in which ECFCs have been shown to have prominent roles in tissue repair, and a summary of current challenges that must be overcome before moving ECFC into human subjects as a cell therapy.

Long-Term Recovery After Endothelial Colony-Forming Cells or Human Umbilical Cord Blood Cells Administration in a Rat Model of Neonatal Hypoxic-Ischemic Encephalopathy

Neonatal hypoxic‐ischemic encephalopathy (NHIE) is a dramatic perinatal complication, associated with poor neurological prognosis despite neuroprotection by therapeutic hypothermia, in the absence of an available curative therapy. We evaluated and compared ready‐to‐use human umbilical cord blood cells (HUCBC) and bankable but allogeneic endothelial progenitors (ECFC) as cell therapy candidate for NHIE. We compared benefits of HUCBC and ECFC transplantation 48 hours after injury in male rat NHIE model, based on the Rice‐Vannucci approach. Based on behavioral tests, immune‐histological assessment and metabolic imaging of brain perfusion using single photon emission computed tomography (SPECT), HUCBC, or ECFC administration provided equally early and sustained functional benefits, up to 8 weeks after injury. These results were associated with total normalization of injured hemisphere cerebral blood flow assessed by SPECT/CT imaging. In conclusion, even if ECFC represent an efficient candidate, HUCBC autologous criteria and easier availability make them the ideal candidate for hypoxic‐ischemic cell therapy. Stem Cells Translational Medicine2017;6:1987–1996