Faculty Bibliography

Objective: Granule cell precursors (GCPs) are a sonic hedgehog (SHH)- dependent progenitor population in the developing cerebellum and the main cell of origin for the SHH subgroup of medulloblastoma (MB). Unlike other subgroups of MB, SHH-MBs occur preferentially in the lateral cerebellum (hemispheres) and have four main driver mutations. We studied whether the timing or type of mutation affects tumor location and identified factors influencing SHH-MB progression.
Method(s): We analyzed the association between type of mutation and tumor location in 38 SHH-MB patient samples. To generate sporadic mouse models of SHH-MB, inducible recombinases were used to express a constitutive activate SMO receptor (SmoM2) or delete Ptch1 in only scattered GCPs. Tumor location, expression profiles and GCP behaviors were analyzed in the models.
Result(s): Our analysis of patient data indicates that adult tumors with SMO mutations form more specifically in the hemispheres than those with PTCH1 mutations. Using sporadic mouse models, we found that regardless of the number of GCPs mutated, timing or type of mutation, tumors developed almost exclusively in the hemispheres with SmoM2-mutants showing a stronger specificity. We further uncovered that GCPs in the hemispheres are more susceptible to high level SHH signaling compared to GCPs in the medial cerebellum (vermis), as more mutant cells in the hemisphere remain undifferentiated and show increased tumorigenicity when transplanted. We also identified location-specific gene expression profiles, and found that deletion of the genes most highly expressed in the hemispheres or vermis showed opposing effects on GCP differentiation.
Conclusion(s): We found that GCPs respond differentially to two driver mutations and a subset of GCPs is more susceptible to high level of SHH signaling as well as tumors formation. We redefined themain cell of origin by showing that GCPs are heterogeneous with molecularly distinct populations based on their location

Uterus transplantation is an emerging technology adding to the arsenal of treatments for infertility; specifically the only available treatment for uterine factor infertility. Ethical investigations concerning risks to uteri donors and transplant recipients have been discussed in the literature. However, missing from the discourse is the potential of uterus transplantation in other groups of genetically XY women who experience uterine factor infertility. There have been philosophical inquiries concerning uterus transplantation in genetically XY women, which includes transgender women and women with complete androgen insufficiency syndrome. We discuss the potential medical steps necessary and associated risks for uterus transplantation in genetically XY women. Presently, the medical technology does not exist to make uterus transplantation a safe and effective option for genetically XY women, however this group should not be summarily excluded from participation in trials. Laboratory research is needed to better understand and reduce medical risk and widen the field to all women who face uterine factor infertility.

Monocytes are circulating cells imperative to the response against pathogens. Upon infection, they are quickly recruited to the affected tissue where they can differentiate into specialized phagocytes and antigen-presenting cells. Additionally, monocytes play a vital role in chronic inflammation, where they can promote and enhance inflammation or induce its resolution. There are two major subsets of monocytes, "inflammatory" and "nonclassical," which are believed to have distinct functions. In atherosclerosis, both types of monocytes are constantly recruited to lesions, where they contribute to plaque formation and atherosclerosis progression. Surprisingly, these cells can also be recruited to lesions and promote resolution of atherosclerosis. Tracking these cells in various disease stages may inform about the dynamic changes occurring in the inflamed and resolving tissues. In this chapter we will discuss methods for differential labeling of the two monocyte subsets in order to examine their dynamics in inflammation.

The prevalence of infection in chronic wounds is well documented in the literature, but not optimally studied due to the drawbacks of current methodologies. Here, we describe a tractable and simplified ex vivo human skin model of infection that addresses the critical drawbacks of high costs and limited translatability. Wounds were generated from excised abdominal skin from cosmetic procedures and cultured, inoculated with Staphylococcus aureus strain UAMS-1, or under aseptic conditions. After three days, the infected wounds exhibited biofilm formation and significantly impaired re-epithelialization compared to the control. Additionally, pro-migratory and pro-reparative genes were significantly downregulated while pro-inflammatory genes were significantly upregulated, demonstrating molecular characterizations of impaired healing as in chronic wounds. This model allows for a simplified and versatile tool for the study of wound infection and subsequent development of novel therapies.

IgE antibodies are essential mediators of allergies. In a recent study in Science, Croote et al. (2018) characterize IgE cells isolated from individuals allergic to peanuts. Their findings provide insight into the differentiation of IgE cells in humans and have implications for our understanding of allergic disease.

AIM/OBJECTIVE:Adolescence is a crucial stage of psychological development and is critically vulnerable to the onset of psychopathology. Our understanding of how the maturation of endocrine, epigenetics, and brain circuit may underlie psychological development in adolescence, however, has not been integrated. Here, we introduce our research project, the population-neuroscience study of the Tokyo TEEN Cohort (pn-TTC), a longitudinal study to explore the neurobiological substrates of development during adolescence. METHODS:Participants in the first wave of the pn-TTC (pn-TTC-1) study were recruited from those of the TTC study, a large-scale epidemiological survey in which 3171 parent-adolescent pairs were recruited from the general population. Participants underwent psychological, cognitive, sociological, and physical assessment. Moreover, adolescents and their parents underwent magnetic resonance imaging (MRI; structural MRI, resting-state functional MRI, and magnetic resonance spectroscopy), and adolescents provided saliva samples for hormone analysis and for DNA analysis including epigenetics. Furthermore, the second wave (pn-TTC-2) followed similar methods as in the first wave. RESULTS:A total of 301 parent-adolescent pairs participated in the pn-TTC-1 study. Moreover, 281 adolescents participated in the pn-TTC-2 study, 238 of whom were recruited from the pn-TTC-1 sample. The instruction for data request is available at: http://value.umin.jp/data-resource.html. CONCLUSION/CONCLUSIONS:The pn-TTC project is a large-scale and population-neuroscience-based survey with a plan of longitudinal biennial follow up. Through this approach we seek to elucidate adolescent developmental mechanisms according to biopsychosocial models. This current biomarker research project, using minimally biased samples recruited from the general population, has the potential to expand the new research field of population neuroscience.

BACKGROUND:/UNASSIGNED:Changes in the joint microenvironment after an injury to the articular surface of the knee have been implicated in the pathogenesis of osteoarthritis. While prior studies focused on changes in this microenvironment after anterior cruciate ligament ruptures, few have explored the biomarker changes that occur in the setting of meniscal injuries. PURPOSE:/UNASSIGNED:To determine whether meniscal injury results in significant alterations to synovial fluid biomarker concentrations as compared with noninjured contralateral knees. Additionally, to explore the relationship between synovial fluid biomarkers and the degree of cartilage injury seen in these patients. STUDY DESIGN:/UNASSIGNED:Cross-sectional study; Level of evidence, 3. METHODS:/UNASSIGNED:Patients undergoing surgery for unilateral meniscal injury were prospectively enrolled from October 2011 to December 2016, forming a cohort that had synovial fluid samples collected from both the injured knee and the contralateral uninjured knee at the time of meniscal surgery. Synovial fluid samples were collected just before incision, and the concentrations of 10 biomarkers of interest were determined with a multiplex magnetic bead immunoassay. The concentrations of synovial fluid biomarkers from the operative and contralateral knees were compared. Additionally, the synovial fluid biomarker concentrations of operative knees from patients with associated high-grade cartilage lesions were compared with those with low-grade lesions. RESULTS:/UNASSIGNED:The current analysis included synovial fluid samples from 82 knees (41 operative and 41 contralateral) from 41 patients undergoing arthroscopic surgery to treat a symptomatic meniscal injury. The mean ± SD age of patients was 49.86 ± 11.75 years. There were significantly greater concentrations of 4 of the 5 proinflammatory biomarkers (IL-6, MCP-1, MIP-1β, and MMP-3) in symptomatic knees as compared with asymptomatic knees when controlling for the duration of symptoms, body mass index, age, and the random effects of by-patient variability. In the injured knees, associated high-grade cartilage lesions were predictive of elevated MCP-1, MIP-1β, and VEGF levels. Low synovial fluid concentration of TIMP-1 or a greater ratio of MMP-3 to TIMP-1 was associated with the presence of synovitis. Increasing age was found to be an independent predictor of increased IL-6, MCP-1, and VEGF concentrations in the setting of symptomatic meniscal injury. CONCLUSION:/UNASSIGNED:The authors identified 4 proinflammatory synovial fluid biomarkers whose concentrations were significantly different after meniscal injury as compared with uninjured contralateral knees. Furthermore, they describe the effects of associated cartilage damage, synovitis, and patient age on biomarker concentrations.

Radiotherapy can be synergistically combined with immunotherapy in mouse models, extending its efficacious effects outside of the irradiated field (abscopal effects). We previously reported that a regimen encompassing local radiotherapy in combination with anti-CD137 plus anti-PD-1 mAbs achieves potent abscopal effects against syngeneic transplanted murine tumors up to a certain tumor size. Knowing that TGF-beta expression or activation increases in irradiated tissues, we tested whether TGF-beta blockade may further enhance abscopal effects in conjunction with the anti-PD-1 plus anti-CD137 mAb combination. Indeed, TGFβ blockade with 1D11, a TGFβ neutralizing monoclonal antibody, markedly enhanced abscopal effects and overall treatment efficacy against subcutaneous tumors of either 4T1 breast cancer cells or large MC38 colorectal tumors. Increases in CD8 T cells infiltrating the non-irradiated lesion were documented upon combined treatment, which intensely expressed Granzyme-B as an indicator of cytotoxic effector capability. Interestingly, tumor tissue but not healthy tissue irradiation results in the presence of higher concentrations of TGFβ in the non-irradiated contralateral tumor which showed smad2/3 phosphorylation increases in infiltrating CD8 T cells. In conclusion, radiotherapy-induced TGF-beta hampers abscopal efficacy even upon combination with a potent immunotherapy regimen. Therefore TGF-beta blockade in combination with radioimmunotherapy results in greater efficacy.

The Japan Obstetric Compensation System for Cerebral Palsy (JOCS-CP), which investigates, develops preventive mechanisms and awards monetary compensation, to cases of cerebral palsy was urgently introduced in 2009 in response to growing concern about Japan's deteriorating perinatal care and low birthrate. Under the political leadership, the Japan Council for Quality Health Care launched the JOCS-CP with support of various stakeholders. The JOCS-CP features of no-fault-based compensation which was discussed decades ago in the Japan Medical Association aiming at financial aid to patient and family and early settlement of dispute. As of 2017, 2233 petitions had been approved by the Review Committee for compensation. All the approved cases were consecutively put on analysis in the Investigation Committee which has compiled more than 1000 Investigative Reports. The reports were delivered not only to the childbirth facility but to the guardians/families. Survey revealed that most of childbirth facility and the guardians/families responded in favor of the reports. With regard to amelioration of profound cerebral palsy, the Prevention Report has been published on annual basis through analysis of all the Investigative Reports. The Prevention Reports and other educational materials were produced and distributed not only among medical professionals but among pregnant women. It is notable that the number of lawsuit filing related to obstetrics demonstrated rapid decrease compared to that of other medical specialties. The JOCS-CP could be described as a social experiment. It was overhauled in 2015 but deserves further discussion on reform for evolving into better system.

Tissue microstructure modeling of diffusion MRI signal is an active research area striving to bridge the gap between macroscopic MRI resolution and cellular-level tissue architecture. Such modeling in neuronal tissue relies on a number of assumptions about the microstructural features of axonal fiber bundles, such as the axonal shape (e.g., perfect cylinders) and the fiber orientation dispersion. However, these assumptions have not yet been validated by sufficiently high-resolution 3-dimensional histology. Here, we reconstructed sequential scanning electron microscopy images in mouse brain corpus callosum, and introduced a random-walker (RaW)-based algorithm to rapidly segment individual intra-axonal spaces and myelin sheaths of myelinated axons. Confirmed by a segmentation based on human annotations initiated with conventional machine-learning-based carving, our semi-automatic algorithm is reliable and less time-consuming. Based on the segmentation, we calculated MRI-relevant estimates of size-related parameters (inner axonal diameter, its distribution, along-axon variation, and myelin g-ratio), and orientation-related parameters (fiber orientation distribution and its rotational invariants; dispersion angle). The reported dispersion angle is consistent with previous 2-dimensional histology studies and diffusion MRI measurements, while the reported diameter exceeds those in other mouse brain studies. Furthermore, we calculated how these quantities would evolve in actual diffusion MRI experiments as a function of diffusion time, thereby providing a coarse-graining window on the microstructure, and showed that the orientation-related metrics have negligible diffusion time-dependence over clinical and pre-clinical diffusion time ranges. However, the MRI-measured inner axonal diameters, dominated by the widest cross sections, effectively decrease with diffusion time by ~ 17% due to the coarse-graining over axonal caliber variations. Furthermore, our 3d measurement showed that there is significant variation of the diameter along the axon. Hence, fiber orientation dispersion estimated from MRI should be relatively stable, while the "apparent" inner axonal diameters are sensitive to experimental settings, and cannot be modeled by perfectly cylindrical axons.