This is a protocol for derivation of glial restricted precursor (GRP) cells from the spinal cord of E13 mouse fetuses. These cells are early precursors within the oligodendrocytic cell lineage. Recently, these cells have been studied as potential source for restorative therapies in white matter diseases. Periventricular leukomalacia (PVL) is the leading cause of non-genetic white matter disease in childhood and affects up to 50% of extremely premature infants. The data suggest a heightened susceptibility of the developing brain to hypoxia-ischemia, oxidative stress and excitotoxicity that selectively targets nascent white matter. Glial restricted precursors (GRP), oligodendrocyte progenitor cells (OPC) and immature oligodendrocytes (preOL) seem to be key players in the development of PVL and are the subject of continuing studies. Furthermore, previous studies have identified a subset of CNS tissue that has increased susceptibility to glutamate excitotoxicity as well as a developmental pattern to this susceptibility. Our laboratory is currently investigating the role of oligodendrocyte progenitors in PVL and use cells at the GRP stage of development. We utilize these derived GRP cells in several experimental paradigms to test their response to select stresses consistent with PVL. GRP cells can be manipulated in vitro into OPCs and preOL for transplantation experiments with mouse PVL models and in vitro models of PVL-like insults including hypoxia-ischemia. By using cultured cells and in vitro studies there would be reduced variability between experiments which facilitates interpretation of the data. Cultured cells also allows for enrichment of the GRP population while minimizing the impact of contaminating cells of non-GRP phenotype.

Background: Growing data on suicidal behavior among members of the lesbian, gay, bisexual, transgender, queer, questioning, and other sexual/gender minority (LGBTQ+) communities, particularly in the transgender subgroup, demonstrate that there is a stark elevation in suicidality compared with rates in their cisgender counterparts. Among the available theories of suicide, the interpersonal theory of suicide (IPTS) is a plausible explanation for the increased suicidal behaviors among transgender youths. Objective: The objective of this study was to examine the pathologic basis of treatmentresistant suicidality in transgender youth despite favorable environments using the theoretical framework of the IPTS, supported by a literature review and case series. Methods: We conducted a literature review using PubMed and PsycInfo with key words suicidal ideation, suicidality, transgender, transgender youth, gender dysphoria, and interpersonal theory of suicide. Seventy-eight articles were retrieved, which were then narrowed down to 30 articles after non-English articles and irrelevant topics were excluded. The clinical presentations of 5 transgender youths, 11 to 17 years of age, were found to be correlated with relevant reports in the research literature, implying a plausible rationale for elevated rates of suicide. All patients and families supplied verbal consent for these case reports to be published. Results: Reasons for suicidal behavior among the patients included thwarted belongingness and perceived burdensomeness leading to perpetual suicidal behavior. The presence in these cases of the following contributing factors in the IPTS-thwarted belongingness, perceived burdensomeness, and acquired capability for suicide-suggests that such a basis exists. Perceived burdensomeness appears to have a greater correlation with developing suicidal behavior than thwarted belongingness alone, but the presence of both demonstrates the highest risk of suicidality in transgender youth. Transgender children and adolescents are at extremely high risk of suicidal behavior, but little research has been devoted to the etiology and plausible explanations for this elevated risk, despite growing awareness of and support for the problem. This review suggests further research is required on the triadic factor interactions of the IPTS model that could help us to better understand and intervene with this high-risk population.