Stem Cell Implants: Emerging Innovation for Stroke Recovery

Stroke is a debilitating neurovascular injury that those effects hundreds of thousands of Americans each year. Despite the high prevalence, disease morbidity and mortality, options for stroke intervention and rehabilitation are still limited. Stem cells have shown promise in stroke treatment due to their ability to self-renew and differentiate into different cell types. The primary sources of stem cells used today are bone marrow and fetal brain tissue, with mesenchymal stem cells, bone marrow stem cells and neural stem cells being particularly well-studied. By secreting therapeutic and neurogenic substances they are hypothesized to help foster recovery at the site of injury. Delivery mechanisms for stem cell therapy include intracerebral, intra-arterial, intraperitoneal, intravenous, intraventricular and intranasal routes with radiographic imaging now being used to monitor the progress of stem cell therapies. Stem cell implants have been found to be safe but optimal treatment strategies are still being established with several promising studies underway. Future efforts should continue to focus on improving efficacy, exploring alternative stem cell sources, enhancing migration capability and survival and educating stroke patients on the benefits and risks of stem cell therapy.

Systematic Review of Treatment Options and Therapeutic Responses for Lesions of the Sella and Orbit: Evidence-Based Recommendations

OBJECTIVE

Inflammatory pathologies of the sella and orbit are rare but require prompt diagnosis to initiate effective treatment. Because uniform recommendations for treatment are currently lacking, we performed an evidence-based review to identify recommendations.

METHODS

We performed a literature search of the PubMed, Embase, and Web of Science databases to identify papers evaluating treatment of inflammatory pathologies of the sella and orbit. We used PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to define recommendations, specifically examining aggregated sample sizes, disease-specific patient follow-up, and clinical trials focused on inflammatory diseases of the sella and orbit.

RESULTS

A total of 169 studies were included and organized by disease pathology. Treatments for various pathologies were recorded. Treatment options included surgery, radiation, steroids, targeted treatments, immunomodulators, intravenous immune globulin, and plasmapheresis. Steroids were the most often employed treatment, second-line management options and timing varied. Pathological diagnosis was highly associated with treatment used. Most evidence were level 3 without available control groups, except for 13 trials in neuromyelitis optica with level 1 or 2 evidence.

CONCLUSIONS

This is the first evidence-based review to provide recommendations on specific treatments for pathologies of the orbit and sella. The reported data may be useful to help guide randomized clinical trials and provide resource for clinical management decisions based on the available evidence.

Case Series and Systematic Review of Electronic Scooter Crashes and Severe Traumatic Brain Injury

OBJECTIVE

Electric scooters (e-scooters) are an increasingly popular form of transportation, but their use has also resulted in increased incidence of traumatic brain injury (TBI). Previous reports have predominantly described mild TBI with limited attention to other injury patterns. Our objective was to evaluate the impact of e-scooter use on rates of severe TBI.

METHODS

We performed a multicenter retrospective case review of patients who presented with severe TBI (Glasgow Coma Scale score 3-8) related to e-scooter use and undertook a systematic literature review to identify other reports of severe TBI related to e-scooter use.

RESULTS

Of the 19 patients (mean age, 38 ± 16 years; 73.7% male) included in the case series, 13 (68.4%) experienced a fall and 6 (31.6%) were involved in a collision. Various cerebral injury patterns, associated craniofacial fractures, and cervical spine injuries were also seen. Twelve patients (63.2%) underwent intracranial pressure monitor placement and 6 (31.6%) underwent a decompressive hemicraniectomy. Most patients (n = 12; 63.2%) were discharged to acute rehabilitation, with a median modified Rankin Scale score of 2 at 4.9 ± 7.7 months follow-up (52.6% had a good outcome of modified Rankin Scale score ≤2), but 4 patients died of primary injuries. The systematic review identified 18 studies with 77,069 patients between 2019 and 2021, with 37 patients who required intensive care and 6 patients who had neurosurgical intervention.

CONCLUSIONS

Severe TBI after e-scooter use is associated with high morbidity and is likely underdiagnosed in the literature. Awareness and public policies may be helpful to reduce the impact of injury.

Neuroinflammation and subarachnoid hemorrhage: a revised look at the literature

A key topic for aneurysmal subarachnoid hemorrhage is neuroinflammation. Neuroinflammation can predispose to aneurysm formation and rupture. Neuroinflammation can also result from the blood breakdown products after aneurysm rupture. Recent evidence has shown that perpetual neuroinflammation can contribute to vasospasm and hydrocephalus. Targeting neuroinflammation is a novel mechanism for preventing subsequent neurologic sequalae. In this review, we highlight the pathophysiology of aneurysm formation, the neuroinflammatory surge after rupture including the involved cytokines, and ultimately tie in the contributory clinical relevance. In the last sections, we look at the pre-clinical data and novel avenues for further discovery. This paper will be a useful resource to both the clinician and scientific investigator.

Clinical risk factors associated with cerebrospinal fluid leak in facial trauma: A retrospective analysis

OBJECTIVE

Cerebrospinal fluid (CSF) leak occurs most commonly following skull fracture, with a CSF leakage complicating up to 2% of all head traumas. This study aims to identify demographic and injury characteristics correlated with the highest risk of CSF leak in patients with known facial fractures.

METHODS

Retrospective data was collected from a previously described trauma registry from 2010 to 2019. Patients over 18 years old with any type of facial fracture, known CSF leak status, available neuroimaging, and hospital admission were included. Chi-Square analysis for demographic and injury characteristic data were utilized.

RESULTS

A total of 79 patients with CSF leak and 4907 patients without CSF leak were included in the database. Patients with CSF leak tended to be younger than those without CSF leak (38.45 +/- 0.28 vs 44.08 +/- 0.28, M +/- SE, p = 0.0197). CSF leak depended on the mechanism of injury (MOI; X² =27.02, df=2, p = 0.0000013), with CSF leak rates highest in penetrating injuries (4.87%) and motor vehicle accidents (1.78%) compared to blunt injuries (0.95%); age did not significantly differ between the MOI groups (p = 0.11). CSF leak was also more common in patients with a lower Glasgow coma scale (GCS; 7.95 +/- 0.58 vs 12.21 +/- 0.10, p = 10^-15), LeFort type 2&3 and pan-facial fractures compared to all other facial fracture types (8.9% vs 1.2%, p = 10^-15), and radiographic midline shift (29.4% vs 9.1%, p = 10^-15). There was a trend towards a higher proportion of males in those with CSF leak compared to those without (83.3% vs 73.7% males, p = 0.073), and in patients with prolonged loss of consciousness (LOC; 9.43% with LOC > 1 h vs 2.69% LOC < 1 h, p = 0.056).

CONCLUSION

Facial fractures often present with CSF leak, and certain demographic and injury risk factors including younger age, worse GCS score, evidence of midline shift, and certain mechanisms of injury (penetrating and motor vehicle) are correlated with increased risk and warrant close screening and follow-up for CSF leak detection. LeFort type 2&3 and pan-facial fractures are at high risk of CSF leak.

Characterization, biodistribution and functional Studies of immune-therapeutic Exosomes: implications for inflammatory lung diseases and COVID 19

Dendritic cell (DC)-derived exosomes (DC EXO), natural nanoparticles of endosomal origin, are under intense scrutiny in clinical trials for various inflammatory diseases. DC EXO are well-tolerated by the host and can be custom-tailored for immunomodulatory functions. Previously we documented the efficacy of immunoregulatory DCs EXO (regDCs EXO) as immunotherapy for inflammatory bone disease in-vivo. However, the on- and off-target effects of these therapeutic regDC EXO and how target signaling in acceptor cells is activated is unclear. In the present report, therapeutic regDC EXO were analyzed by high throughput proteomics, with non-therapeutic EXO from immature DCs and mature DCs as controls, to identify shared and distinct proteins and potential off-target proteins. The predominant expression in regDC EXO of immunoregulatory proteins as well as proteins involved in trafficking from the circulation to peripheral tissues, prompted us to investigate how these EXO are biodistributed to major organs after intravenous injection. Live animal imaging showed preferential accumulation of regDCs EXO in the lungs. In addition, TGFB1 in regDCs EXO sustained downstream regulatory signaling in acceptor DCs. Blocking experiments suggested that sustaining TGFB1 signaling require initial interaction of regDCs EXO with TGFB1R followed by internalization of regDCs EXO with TGFB1-TGFB1R complex. Finally, these regDCs EXO that contain immunoregulatory cargo and showed biodistribution to lungs could downregulate the main SARS-CoV-2 target receptor, ACE2 on recipient lung parenchymal cells via TGFB1 in-vitro. In conclusion, these results may have important immunotherapeutic implications for lung inflammatory disorders and COVID19.

Enterococcus faecalis shifts macrophage polarization toward M1-like phenotype with an altered cytokine profile

Background: The macrophage is an innate immune defense cell involved in pathogen recognition and clearance.

Aim: In view of the diversity of the macrophage phenotype and function, the present study investigated how Enterococcus faecalis infection affects the differentiation, phenotype and cytokine profile of macrophages.

Methods: Murine bone marrow-derived stem cells were co-cultured with E. faecalis before and after differentiation. Macrophage M0 polarization towards M1 or M2 was initiated at day 6 by addition of LPS and INF-γ, or IL-4 and IL-13, respectively.

Results: E. faecalis did not inhibit macrophage differentiation and were identified within macrophages. Viability of the macrophages infected with E. faecalis prior to differentiation was enhanced, evidenced by apoptosis inhibition, as was expression of CD38 and IRF5 proteins, indicators of M1-like polarization. These M1-like macrophages expressed an aberrant cytokine mRNA profile, with reduction in inflammatory cytokines IL-1β and IL-12 and increase in regulatory cytokine IL-10. No changes in TNF-α or TGF-β1 were detected, compared with the control groups. This atypical M1-like phenotype was retained even upon stimulation with growth factors that normally trigger their development into M2 macrophages.

Conclusions: These findings suggested that E. faecalis infection of bone marrow-derived stem cells during differentiation into macrophages induces an atypical M1-like phenotype associated with intracellular bacterial survival.

Post-exercise hypotension and skeletal muscle oxygenation is regulated by nitrate-reducing activity of oral bacteria

Post-exercise hypotension (PEH) is a common physiological phenomenon leading to lower blood pressure after acute exercise, but it is not fully understood how this intriguing response occurs. This study investigated whether the nitrate-reducing activity of oral bacteria is a key mechanism to trigger PEH. Following a randomized, double blind and crossover design, twenty-three healthy individuals (15 males/8 females) completed two treadmill trials at moderate intensity. After exercise, participants rinsed their mouth with antibacterial mouthwash to inhibit the activity of oral bacteria or a placebo mouthwash. Blood pressure was measured before, 1h and 2 h after exercise. The microvascular response to a reactive hyperaemia test, as well as blood and salivary samples were taken before and 2 h after exercise to analyse nitrate and nitrite concentrations and the oral microbiome. As expected, systolic blood pressure (SBP) was lower (1 h: -5.2 ± 1.0 mmHg; P < 0.001); 2 h: -3.8 ± 1.1 mmHg, P = 0.005) after exercise compared to baseline in the placebo condition. This was accompanied by an increase of circulatory nitrite 2 h after exercise (2h: 100 ± 13 nM) compared to baseline (59 ± 9 nM; P = 0.013). Additionally, an increase in the peak of the tissue oxygenation index (TOI) during the reactive hyperaemia response was observed after exercise (86.1 ± 0.6%) compared to baseline levels (84.8 ± 0.5%; P = 0.010) in the placebo condition. On the other hand, the SBP-lowering effect of exercise was attenuated by 61% at 1 h in the recovery period, and it was fully attenuated 2 h after exercise with antibacterial mouthwash. This was associated with a lack of changes in circulatory nitrite (P > 0.05), and impaired microvascular response (peak TOI baseline: 85.1 ± 3.1%; peak TOI post-exercise: 84.6 ± 3.2%; P > 0.05). Diversity of oral bacteria did not change after exercise in any treatment. These findings show that nitrite synthesis by oral commensal bacteria is a key mechanism to induce the vascular response to exercise over the first period of recovery thereby promoting lower blood pressure and greater muscle oxygenation.

The oral nitrate-reducing capacity correlates with peak power output and peak oxygen uptake in healthy humans

Interest in inorganic nitrate and nitrite has grown substantially over the past decade as research has revealed the role of these anions in enhancing nitric oxide (NO) availability through an oral pathway. Nitrite synthesis in the mouth seems to be an important mechanism to feed the circulatory system with this anion. This is interesting since greater plasma nitrite concentration has been associated with better fitness levels in humans, but this question has not been investigated in relation to salivary nitrite concentration. Additionally, no previous study has investigated the oral nitrate-reducing capacity in regards to peak oxygen uptake (VO_2peak) or peak power output (W_peak) in humans. Thus, the main goal of this study was to investigate whether salivary nitrite and nitrate concentration and the oral nitrate-reducing capacity were associated with VO2_peak and W_peak in healthy humans. Fifty individuals (22 females and 28 males; 38.8 ± 14.3 years/old; BMI = 22.8 ± 3.9) performed a graded exercise test on a cycle ergometer to assess their VO_2peak and W_peak. Unstimulated salivary samples were taken before and 20 min after exercise to measure nitrate/nitrite, pH and lactate. The oral nitrate-reducing capacity was also assessed in 25 subjects before and after exercise. Oral nitrate-reducing capacity was positively associated with W_peak (r_s = 0.64; P = 0.001) and the VO_2peak (r_s = 0.54; P = 0.005). Similar correlations were found when these variables were analysed after exercise. In addition, a significant decrease in salivary pH (pre: 7.28 ± 0.361; post-exercise: 7.16 ± 0.33; P = 0.003) accompanied by an increase of salivary lactate (pre: 0.17 ± 0.14 mmol/L; post-exercise: 0.48 ± 0.38; P < 0.001) was found after exercise. However, these changes did not have any impact on salivary nitrate/nitrite concentration and the oral nitrate-reducing capacity after exercise. In conclusion, this is the first evidence showing a link between the oral nitrate-reducing capacity and markers of aerobic fitness levels in healthy humans.

A North American perspective of content and quality of websites in the English language on childhood-onset lupus erythematosus

Objective The objective of this article is to examine the quality, content, and readability of information and resources in the English language and accessible on the internet by pediatric patients with systemic lupus erythematosus (SLE) and their families in North America. Methods Keywords relevant to SLE were generated by an undergraduate student, a first-year medical student, and a third-year pediatric resident, and a search was conducted across five commonly used search engines. Quality of information found was evaluated independently by an undergraduate student, a graduate student, a first-year medical student, and a third-year pediatric resident using the DISCERN tool. Two pediatric rheumatologists assessed website accuracy and completeness. Readability of websites was determined using the Flesch-Kincaid grade level and Reading Ease score. Results Out of 2000 websites generated in the search, only 34 unique websites met inclusion criteria. Only 16 of these websites had DISCERN scores above 50% (fair quality). Overall quality of website information was fair with mean ±standard deviation (SD) DISCERN quality score of 44 ± 7 (range: 30-56). Only nine websites of 34 had DISCERN scores above 50 (>66%, indicating greater quality) and were further assessed for completeness. Flesch-Kincaid grade level was 11 ± 1 (mean±SD) and reading ease score was 39 ± 10 (mean±SD, range of 11-61). Conclusion Our study highlights the need for more complete, readable information regarding the unique needs of pediatric patients with childhood-onset SLE and their families.

The Growth of Older Inmate Populations: How Population Aging Explains Rising Age at Admission

Objectives

Older inmates are the fastest growing segment of the prison population; however, the reasons for this are not well understood. One explanation is that the general population is aging, driving prison age distributions to change. For this article, we study the role of population aging in prison growth by investigating how the baby boom phenomenon of post-World War II has contributed to the growth of older inmate populations.

Method

We identify the impact of population aging using simulation methods that explain prison growth as the combination of criminal justice processes.

Results

Overall, we find evidence that population aging has played a significant role in explaining the growth of older inmate populations, in particular among inmates aged between 50 and 64 years, contributing to as much as half of the observed increase in these groups since 2000.

Discussion

This finding stands in contrast to the notion that population aging has little explanatory power in describing the growth of prison populations and implies that older inmate groups are more sensitive to compositional changes in the general population. We argue that prediction-based modeling of prison growth should more seriously consider the impacts and consequences of demographic shifts among older prisoner populations.

The European Eel NCCβ Gene Encodes a Thiazide-resistant Na-Cl Cotransporter

The thiazide-sensitive Na-Cl cotransporter (NCC) is the major pathway for salt reabsorption in the mammalian distal convoluted tubule. NCC plays a key role in the regulation of blood pressure. Its inhibition with thiazides constitutes the primary baseline therapy for arterial hypertension. However, the thiazide-binding site in NCC is unknown. Mammals have only one gene encoding for NCC. The eel, however, contains a duplicate gene. NCCα is an ortholog of mammalian NCC and is expressed in the kidney. NCCβ is present in the apical membrane of the rectum. Here we cloned and functionally characterized NCCβ from the European eel. The cRNA encodes a 1043-amino acid membrane protein that, when expressed in Xenopus oocytes, functions as an Na-Cl cotransporter with two major characteristics, making it different from other known NCCs. First, eel NCCβ is resistant to thiazides. Single-point mutagenesis supports that the absence of thiazide inhibition is, at least in part, due to the substitution of a conserved serine for a cysteine at position 379. Second, NCCβ is not activated by low-chloride hypotonic stress, although the unique Ste20-related proline alanine-rich kinase (SPAK) binding site in the amino-terminal domain is conserved. Thus, NCCβ exhibits significant functional differences from NCCs that could be helpful in defining several aspects of the structure-function relationship of this important cotransporter.

Dose and time responses of vitamin D biomarkers to monthly vitamin D3 supplementation in overweight/obese African Americans with suboptimal vitamin d status: a placebo controlled randomized clinical trial

Background

A critical need exists to better understand the physiological sequel of vitamin D supplementation in obese individuals and African Americans. The aim was to comprehensively evaluate dose- and time-responses of a panel of vitamin D biomarkers to vitamin D supplements in this population.

Methods

We conducted a 16-week randomized, double-blinded, and placebo-controlled clinical trial. Seventy overweight/obese African Americans (age 13–45 years, 84 % females) with 25-hydroxyvitamin D [25(OH)D] concentrations ≤20 ng/mL were randomly assigned to receive a supervised monthly oral vitamin D₃ of 18,000 IU (~600 IU/day, n = 17), 60,000 IU (~2000 IU/day, n = 18), 120,000 IU (~4000 IU/day, n = 18), or placebo (n = 17).

Results

There were significant dose- and time-responses of circulating 25(OH)D, 1,25-dihydroxyvitamin D [1,25(OH)₂D], and intact parathyroid hormone (iPTH), but not fibroblast growth factor-23 (FGF-23), phosphorus and urine calcium to the vitamin D supplements. The mean 25(OH)D concentrations in the 2000 IU and 4000 IU groups reached ≥30 ng/mL as early as 8-weeks and remained at similar level at 16-weeks. The increase of 25(OH)D was significantly higher in the 4000 IU group than all the other groups at 8-weeks. The increase of 1,25(OH)₂D was significantly higher in the 2000 IU and 4000 IU groups than the placebo at 8-weeks. Only the 4000 IU compared to the placebo significantly reduced iPTH at 8- and 16-weeks.

Conclusions

Our RCT, for the first time, comprehensively evaluated time- and dose- responses of vitamin D supplementation in overweight/obese African Americans with suboptimal vitamin D status. Circulating 25(OH)D, 1,25(OH)2D, and iPTH, but not FGF-23, phosphorus and urine calcium, respond to vitamin D supplementation in a time- and dose–response manner. By monthly dosing, 2000 IU appears to be sufficient in achieving a 25(OH)D level of 30 ng/mL in this population. However, importantly, 4000 IU, rather than 2000 IU, seems to suppress iPTH. If replicated, these data might be informative in optimizing vitamin D status and providing individualized dosing recommendation in overweight/obese African Americans.

Trial registration

ClinicalTrials.gov number: NCT01583621, Registered on April 3, 2012.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Prostaglandin E2 promotes survival of naive UCB T cells via the Wnt/β-catenin pathway and alters immune reconstitution after UCBT

The outcome of umbilical cord blood transplantation (UCBT) is compromised by low hematopoietic stem cell (HSC) doses leading to prolonged time to engraftment, delayed immunological reconstitution and late memory T-cell skewing. Exposure of UCB to dimethyl-prostaglandin E2 (dmPGE2) increases HSC in vivo. We determined that exposure of UCB T lymphocytes to dmPGE2 modified Wnt signaling resulting in T cell factor (TCF)-mediated transcription. Wnt signaling upregulated interleukin (IL)-7R and IL-2Rβ, resulting in enhanced survival mediated by the homeostatic cytokines IL-7 and IL-15. dmPGE2 also induced components of the Wnt pathway and Wnt receptors, thereby priming UCB T cells to receive signals via Wnt ligands in vivo. We observed that the Wnt transcription factor TCF7 and its target EOMES were elevated in the T cells of patients who received PGE2-treated UCBs. Consistent with the role of Wnt/β-catenin signaling to induce and maintain naive, memory precursors and long-lived central memory CD8(+) cells, these patients also had increased fractions of CD8(+)CD45RO(-)CD62L(+) plus CD8(+)CD45RO(+)CD62L(+) subsets encompassing these T-cell populations. These effects of the PGE2/Wnt/β-catenin axis may have significant implications for harnessing immunity in the context of UCBT, where impaired immune reconstitution is associated with late memory T-cell skewing.

Tn and sialyl-Tn antigens, aberrant O-glycomics as human disease markers

In many different human disorders, the cellular glycome is altered. An interesting but poorly understood alteration occurs in the mucin-type O-glycome, in which there is aberrant expression of the truncated O-glycans Tn (GalNAcα1-Ser/Thr) and its sialylated version sialyl-Tn (STn) (Neu5Acα2,6GalNAcα1-Ser/Thr). Both Tn and STn are tumor-associated carbohydrate antigens and tumor biomarkers, since they are not expressed normally and appear early in tumorigenesis. Moreover, their expression is strongly associated with poor prognosis and tumor metastasis. The Tn and STn antigens are also expressed in other human diseases and disorders, such as Tn syndrome and IgA nephropathy. The major pathological mechanism for expression of the Tn and STn antigens is compromised T-synthase activity, resulting from alteration of the X-linked gene that encodes for Cosmc, a molecular chaperone specifically required for the correct folding of T-synthase to form active enzyme. This review will summarize our current understanding of the Tn and STn antigens in terms of their biochemistry and role in pathology.

Measurement of oral chronic GVHD: results from the Chronic GVHD Consortium

Oral chronic GVHD (cGVHD) is a serious complication of alloSCT. Scales and instruments to measure oral cGVHD activity and severity have not been prospectively validated. The objective of this study was to describe the characteristics of oral cGVHD and determine the measures most sensitive to change. Patients enrolled in the cGVHD Consortium with oral involvement were included. Clinicians scored oral changes according to the National Institutes of Health (NIH) criteria, and patients completed symptom and quality-of-life measures at each visit. Both rated change on an eight-point scale. Of the 458 participants, 72% (n=331) had objective oral involvement at enrollment. Lichenoid change was the most common feature (n=293; 89%). At visits where oral change could be assessed, 50% of clinicians and 56% of patients reported improvement, with worsening reported in 4-5% for both the groups (weighted kappa=0.41). Multivariable regression modeling suggested that the measurement changes most predictive of perceived change by clinicians and patients were erythema and lichenoid, NIH severity and symptom scores. Oral cGVHD is common and associated with a range of signs and symptoms. Measurement of erythema and lichenoid changes and symptoms may adequately capture the activity of oral cGVHD in clinical trials but require prospective validation.

DC-SIGN targeting carbohydrate moieties identified on 67 kDa mfa-1 fimbriae of mucosal pathogen Porphyromonas gingivalis (42.7)

We recently reported that the oral mucosal pathogen Porphyromonas gingivalis targets the C- type lectin receptor DC-SIGN for invasion and persistence within human monocyte-derived dendritic cells (DCs). The DCs respond by inducing an immunosuppressive and Th2-biased CD4+ T cell response (Zeituni et al 2009); moreover, DC invasion and immunosuppression are dependent upon expression of the 67 kDa mfa-1 fimbriae by P. gingivalis . We have now purified mfa-1 by ion exchange chromatography and sequenced it by tandem mass spectrometry (MS/MS), confirming its identify and revealing two putative N-glycosylation motifs as well as numerous O-glycosylation motifs. We further show mfa-1 is glycosylated by ProQ staining. Further monosaccharide analysis by gas chromatography-mass spectrometry (GC-MS) confirmed that mfa-1 contains fucose (1.35 nmol/mg) mannose (2.68 nmol/mg), N-acetylglucosamine (2.27 nmol/mg) and N-acetylgalactosamine (0.652 nmol/mg). Analysis by transmission electron microscopy reveals mfa-1 form oligomeric strains approximately 200 nm in length, which could be involved in targeting/ cross-linking DC-SIGN. These findings shed further light on mechanisms of invasion and immunosuppression by this unique mucosal pathogen.

Blood dendritic cells in cardiovascular disease risk (44.13)

An estimated 80 million U.S. adults have one or more types of cardiovascular diseases (CVD) with the total cost to the U.S. for 2009 estimated to be $475.3 billion. Atherosclerosis (ATH) is the single most important contributor to CVD; however, only 50% of ATH patients have currently identified risk factors. Chronic periodontitis (CP), a common inflammatory disease, is linked to an increased CVD risk. Dendritic cells (DCs) which infiltrate arterial walls and destabilize atherosclerotic plaques, have been implicated in CVD. While the source of atherogenic DCs is presently unclear, we propose that dermal DCs from peripheral inflamed sites, such as CP tissues are a source. We therefore designed a clinical study to elicit, quantitate and isolate DCs in the peripheral blood of otherwise healthy CP patients. Ten patients with CP were consented according to IRB standards and enrolled in the study. Peripheral blood collected at baseline and 24 hrs after mechanical debridement (MD) was used to identify and sort blood DCs. After PBMC separation, DCs were labeled with DC-SIGN-APC and BDCA-1-PE and quantitated by FACS analysis. We found that after MD there was a 5-6% increase in the numbers of blood DCs in this patient population. This increase in the blood may represent mobilization of DCs from bone marrow stores, as well as from CP tissues. We are presently analyzing the DC transcriptome of sorted DCs to identify markers of atherogenesis.

Radiometal complexes: characterization and relevant in vitro studies

Radiometals are, and will continue to be, very important to diagnostic and therapeutic nuclear medicine applications as they predominantly possess the most suitable nuclear properties for these types of applications. This article attempts to give the reader an overview of key aspects that need to be considered in the design and synthesis of a radiopharmaceutical using the commonly known and employed radionuclides, such as technetium, rhenium, the lanthanides and copper. While it is important to understand each radiometal ion has its own specific coordination chemistry requirements, there are several issues that are critical to all radiometal ions for their incorporation into a radiopharmaceutical. 1) The route of production and the presence of long lived contaminating radionuclides and or of naturally occurring metal ions that will interfere with the efficient and optimum radiolabelling of their ligand of choice as well as the final specific activity of the product; 2) the significant differences between the chemistry at the macroscopic (mM and higher concentrations) and radiotracer levels (uM and lower concentrations for the high specific activity radionuclides); 3) the rate of complexation and of dissociation of the radiometal ion vs the competing reaction of radiometal hydrolysis; 4) natural biological pathway of the radio-metal ion and therefore the design of the appropriate and relevant in vitro tests to assess the stability of the radiometal complex. These are a selection of critical factors that need to be considered in the design of a successful radiopharmaceutical, whether it is used for imaging or therapy. However, one should consider tailoring their investigations to suit the radiometal under investigation, and to be mindful where the technology is to be applied (e.g. imaging organs or disease).

Preinfusion variables predict the predominant unit in the setting of reduced-intensity double cord blood transplantation

Double cord blood transplantation (DCBT) may overcome the slow hematopoietic recovery and engraftment failure associated with infusion of a single cord blood unit. In DCBT, only one unit typically contributes to long-term hematopoiesis, but little is known about factors affecting cord predominance. As results from a phase I trial suggested that order of infusion may affect cord predominance, we analyzed the effect of preinfusion variables on chimerism patterns of 38 patients enrolled in the initial study and a subsequent phase II trial. All patients were treated with a reduced-intensity conditioning (RIC) regimen of fludarabine, melphalan and thymoglobulin followed by DCBT. By day 100, 66% of patients had hematopoiesis derived from a single cord blood unit. Higher post-thaw total nucleated cell and CD34+ cell dose were associated with cord predominance and in 68% of patients (P=0.03); the predominant cord blood unit was infused first. Only the post-thaw CD34+ cell dose of the predominant unit predicted time to both neutrophil and platelet engraftment. Although based on a small number of patients, our results identify parameters that may affect cord predominance and engraftment in the setting of DCBT following RIC and suggest possible strategies for selecting infusion order for cord blood units.