Stephen K. Klasko

Umbilical Cord Blood‐Derived Stem Cells and Brain Repair

Abstract: Human umbilical cord blood (HUCB) is now considered a valuable source for stem cell‐based therapies. HUCB cells are enriched for stem cells that have the potential to initiate and maintain tissue repair. This potential is especially attractive in neural diseases for which no current cure is available. Furthermore, HUCB cells are easily available and less immunogenic compared to other sources for stem cell therapy such as bone marrow. Accordingly, the number of cord blood transplants has doubled in the last year alone, especially in the pediatric population. The therapeutic potential of HUCB cells may be attributed to inherent ability of stem cell populations to replace damaged tissues. Alternatively, various cell types within the graft may promote neural repair by delivering neural protection and secretion of neurotrophic factors. In this review, we evaluate the preclinical studies in which HUCB was applied for treatment of neurodegenerative diseases and for traumatic and ischemic brain damage. We discuss how transplantation of HUCB cells affects these disorders and we present recent clinical studies with promising outcome.

Mannitol facilitates neurotrophic factor up‐regulation and behavioural recovery in neonatal hypoxic‐ischaemic rats with human umbilical cord blood grafts

We recently demonstrated that blood–brain barrier permeabilization using mannitol enhances the therapeutic efficacy of systemically administered human umbilical cord blood (HUCB) by facilitating the entry of neurotrophic factors from the periphery into the adult stroke brain. Here, we examined whether the same blood–brain barrier manipulation approach increases the therapeutic effects of intravenously delivered HUCB in a neonatal hypoxic‐ischaemic (HI) injury model. Seven‐day‐old Sprague–Dawley rats were subjected to unilateral HI injury and then at day 7 after the insult, animals intravenously received vehicle alone, mannitol alone, HUCB cells (15k mononuclear fraction) alone or a combination of mannitol and HUCB cells. Behavioural tests at post‐transplantation days 7 and 14 showed that HI animals that received HUCB cells alone or when combined with mannitol were significantly less impaired in motor asymmetry and motor coordination compared with those that received vehicle alone or mannitol alone. Brain tissues from a separate animal cohort from the four treatment conditions were processed for enzyme‐linked immunosorbent assay at day 3 post‐transplantation, and revealed elevated levels of GDNF, NGF and BDNF in those that received HUCB cells alone or when combined with mannitol compared with those that received vehicle or mannitol alone, with the combined HUCB cells and mannitol exhibiting the most robust neurotropic factor up‐regulation. Histological assays revealed only sporadic detection of HUCB cells, suggesting that the trophic factor–mediated mechanism, rather than cell replacement per se, principally contributed to the behavioural improvement. These findings extend the utility of blood–brain barrier permeabilization in facilitating cell therapy for treating neonatal HI injury.

Umbilical cord blood research: current and future perspectives.

Umbilical cord blood (UCB) banking has become a new obstetrical trend. It offers expectant parents a biological insurance policy that can be used in the event of a child or family members life-threatening illness and puts patients in a position of control over their own treatment options. However, its graduation to conventional therapy in the clinical realm relies on breakthrough research that will prove its efficacy for a range of ailments. Expanding the multipotent cells found within the mononuclear fraction of UCB so that adequate dosing can be achieved, effectively expanding desired cells ex vivo, establishing its safety and limitations in HLA-mismatched recipients, defining its mechanisms of action, and proving its utility in a wide variety of both rare and common illnesses and diseases are a few of the challenges left to tackle. Nevertheless, the field is moving fast and new UCB-based therapies are on the horizon.

Novel cell therapy approaches for brain repair.

Numerous reports elucidate that tissue-specific stem cells are phenotypically plastic and their differentiation pathways are not strictly delineated. Although the identity of all the epigenetic factors which may trigger stem cells to make a lineage selection are still unknown, the plasticity of adult stem cells opens new approaches for their application in the treatment of various disorders. There is increasing researcher interest in hematopoietic stem cells for treatment of not only blood-related diseases but also various unrelated disorders including neurodegenerative diseases. Human umbilical cord blood (hUCB) cells, due to their primitive nature and ability to develop into nonhematopoietic cells of various tissue lineages, including neural cells, may be useful as an alternative cell source for cell-based therapies requiring either the replacement of individual cell types and/or substitution of missing substances. Here we focus on recent findings showing the robustness of adult stem cells derived from hUCB and their potential as a source of transplant cells for the treatment of diseased or injured brains and spinal cords. Depending upon the pathological microenvironment in which the hUCB cells are introduced, neuroprotective and/or trophic effects of these cells, from release of various growth or anti-inflammatory factors to moderation of immune-inflammatory effectors, may be more likely than neural replacement. These protective effects may prove essential to maintaining restored tissue integrity over the course of various diseases or injuries.

Inflammation and Stem Cell Migration to the Injured Brain in Higher Organisms

Current treatments of neurological disorders such as Parkinsons disease and stroke are only partially effective. Consequently new therapies such as cell transplantation are of great interest. Cell therapy has shown promising results in animal models and in limited clinical trials. This form of treatment does have its own concerns, such as what factors control the survival and/or migration of the transplanted cells and how do they exert their benefit. Recent studies on tracking the transplants, such as prelabeling of the cells prior to transplant, and those elucidating the role of chemokines, as well as microglial and inflammatory responses, that may initiate the movement and survival of these cells are discussed in this review. A better understanding of these mechanism-driven pathways of neural repair will facilitate the clinical application of cell therapy for neurological disorders.

Mankind’s first natural stem cell transplant

•  Introduction •  Early haematopoiesis in foetus •  Early versus late clamping of the umbilical cord •  Stem cells in human umbilical cord blood ‐  Cellular composition ‐  Usefulness of umbilical cord blood stem cells •  First stem cell transplantation at birth •  Conclusions

A study on intrauterine fetal resuscitation with terbutaline

A randomized study on the effect of terbutaline on fetal distress was carried out in 20 patients who showed evidence of ominous fetal heart rate patterns and fetal scalp blood pH values of less than 7.25. Of those, 11 received terbutaline (study group) and nine did not (control group). There was a significant improvement in the acid-base status of the fetus in the study group compared with those in the control group (p less than 0.01). No significant maternal or fetal morbidity occurred in the study group. Apgar scores at 1 minute were 7 or greater in 10 of the 11 study subjects whereas only four of the nine control subjects had a score of 7 or greater. These results suggest that terbutaline may become a useful agent in the treatment of intrauterine fetal distress.

Maternal transplantation of human umbilical cord blood cells provides prenatal therapy in Sanfilippo type B mouse model

Numerous data support passage of maternal cells into the fetus during pregnancy in both human and animal models. However, functional benefits of maternal microchimerism in utero are unknown. The current study attempted to take advantage of this route for prenatal delivery of ?N‐acetylglucosaminidase (Naglu) enzyme into the enzyme‐deficient mouse model of Sanfilippo syndrome type B (MPS III B). Enzymatically sufficient mononuclear cells from human umbilical cord blood (MNC hUCB) were intravenously administered into heterozygote females modeling MPS III B on the 5th day of pregnancy during blastocyst implantation. The major findings were 1) administered MNC hUCB cells transmigrated and diffused into the embryos (E12.5); 2) some transmigrated cells expressed CD34 and CD117 antigens; 3) transmigrated cells were found in both the maternal and embryonic parts of placentas; 4) transmigrated cells corrected Naglu enzyme activity in all embryos; 5) administered MNC hUCB cells were extensively distributed in the organs and the blood of heterozygote mothers at one week after transplantation. Results indicate that prenatal delivery of Naglu enzyme by MNC hUCB cell administration into mothers of enzyme‐deficient embryos is possible and may present a significant opportunity for new biotechnologies to treat many inherited disorders.

Intravenous administration of human umbilical cord blood cells in an animal model of MPS III B

Sanfilippo syndrome type B (MPS III B) is caused by a deficiency of α‐N‐acetylglucosaminidase enzyme (Naglu), leading to accumulation of heparan sulfate (HS), a glycosaminoglycan (GAG), within lysosomes and to eventual progressive cerebral and systemic multiple organ abnormalities. Treatment of MPS patients is mainly supportive and enzyme replacement cell therapy shows promise for treating this disease. One new approach for potential treatment of MPS III B is human umbilical cord blood (hUCB) cell transplantation. Recently, we demonstrated that administration of hUCB cells into the cerebral ventricle of presymptomatic Naglu mice had a beneficial effect, probably due to enzyme delivery into the enzyme‐deficient mutant mice. However, administration of these cells into the systemic circulation of mutant mice could be more advantageous and may lead to new strategies of enzyme replacement for Sanfilippo. The aim of this study was to determine the effect of intravenous administration of hUCB cells into a mouse model of Sanfilippo Syndrome type B. The major findings in our study were that hUCB cell administration improved behavioral outcomes (decreased hyper/stereotypical activity and improved cognitive function). Cells widely distribute within and outside the CNS and intraparenchymally migrate. Administered cells have an antiinflammatory effect (Th2‐associated cytokines) in the brain and reduce heparan sulfate accumulation in the liver and spleen. Our results demonstrate the advantages of intravenously administering hUCB cells into a mouse model of Sanfilippo Syndrome type B, the advantages probably a result of Naglu delivery to enzyme‐deficient organs. J. Comp. Neurol. 515:93–101, 2009.

Does Centralized Monitoring Affect Perinatal Outcome

A retrospective study was performed comparing centralized monitoring to noncentralized monitoring in regard to perinatal outcome. The study was conducted at Lehigh Valley Hospital (Allentown, PA) between August 1994 and February 1995. All deliveries during a 28-week-period were studied retrospectively. The study was designed such that for 14 weeks all patients were centrally monitored (Group A). During the following 14 weeks, no patients were centrally monitored (Group B). Patients not requiring monitoring, such as elective cesarean sections, were excluded from the study. The variables that were studied were the 5-minute Apgar, cord blood pH, perinatal mortality, admissions to the neonatal intensive care unit (NICU), spontaneous vaginal deliveries, cesarean sections, and operative vaginal deliveries. A total of 1,622 deliveries occurred during the 28 weeks of antenatal care. Group A consisted of 805 centralized monitored patients and Group B had 817 noncentralized monitored patients. There was no statistical difference in the 5-minute Apgar, umbilical artery pH, perinatal mortality, or the NICU admissions between the two groups. However, there was a significant statistical difference in the percent of cesarean sections performed for nonreassuring fetal heart rate tracings (Group A, 17.89% vs. Group B, 12.16%; P = 0.02). The overall cesarean section rate was increased in the centrally monitored group (Group A, 23.6% vs. Group B, 18.1%; P = 0.01). There were also statistically significant differences in operative vaginal deliveries (forceps and vacuum) for fetal heart rate abnormalities between Group A, 0.52% vs. Group B, .39% (P = 0.05). Centralized monitoring may be associated with an increase in the overall cesarean section rate. In addition, the rate of operative vaginal and abdominal deliveries appears to be increased for the indication of nonreassuring fetal heart rate tracings with the use of centralized monitoring.