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Given the current unprecedented multiple pandemics of COVID-19, anti-Black and anti-Asian violence, and white supremacy, we—a group of graduate students and a faculty member who hold diverse identities across disciplines, race, gender, nationality, and additional categories—came together to focus on qualitative research as an ontological, epistemological, and axiological space toward community and culture change. Specifically, we took up scholarly personal narrative, which centers postmodernism and focuses on the reality that “we see what we believe; we observe what we narrate; we transform what we reframe.” What emerged were radical interrelated understandings of privilege, guilt, and the importance of kinship. As such, this vulnerable group reflected on graduate student experiences with multiple pandemics and how the academy may enact transformative change, reframing our own understandings of qualitative space.

Glioblastoma multiforme (GBM) is among the most aggressive, treatment-resistant cancers, and despite standard of care surgery, radiation and chemotherapy, is invariably fatal. GBM is marked by local and systemic immunosuppression, contributing to resistance to existing immunotherapies that have had success in other tumor types. Memory T cells specific for previous infections reside in tissues throughout the host and are capable of rapid and potent immune activation. Here, we show that virus-specific memory CD8 + T cells expressing tissue-resident markers populate the mouse and human glioblastoma microenvironment. Reactivating virus-specific memory T cells through intratumoral delivery of adjuvant-free virus-derived peptide triggered local immune activation. This delivery translated to antineoplastic effects, which improved survival in a murine glioblastoma model. Our results indicate that virus-specific memory T cells are a significant part of the glioblastoma immune microenvironment and may be leveraged to promote anti-tumoral immunity.

Glioblastoma multiforme (GBM) is among the most aggressive, treatment resistant cancers, and despite standard of care surgery, radiation and chemotherapy, is invariably fatal. GBM is marked by local and systemic immunosuppression, contributing to resistance to existing immunotherapies that have had success in other tumor types. Memory T cells specific for previous infections reside in tissues throughout the host and these tissue resident memory T cells (TRM) are capable of rapid and potent immune activation. Here, we show that virus-specific memory CD8+ T cells expressing tissue resident markers populate mouse and human glioblastoma microenvironment. Reactivating virus-specific TRM through intra-tumoral delivery of adjuvant-free virus-derived peptide triggered local immune activation. This delivery translated to anti-neoplastic effects, which improved survival in a murine glioblastoma model. Our results indicate that virus-specific TRM are a significant part of the glioblastoma immune microenvironment and can be leveraged to promote anti-tumoral immunity.

Adeno-associated viral (AAV) vectors allow for site-specific and time-dependent genetic manipulation of neurons. However, for successful implementation of AAV vectors, major consideration must be given to the selection of viral serotype and route of delivery for efficient gene transfer into the cell type being investigated. Here we compare the transduction pattern of neurons in the somatosensory system following injection of AAV9 or AAV2retro in the parabrachial complex of the midbrain, the spinal cord dorsal horn, the intrathecal space, and the colon. Transduction was evaluated based on Cre-dependent expression of tdTomato in transgenic reporter mice, following delivery of AAV9 or AAV2retro carrying identical constructs that drive the expression of Cre/GFP. The pattern of distribution of tdTomato expression indicated notable differences in the access of the two AAV serotypes to primary afferent neurons via peripheral delivery in the colon and to spinal projections neurons via intracranial delivery within the parabrachial complex. Additionally, our results highlight the superior sensitivity of detection of neuronal transduction based on reporter expression relative to expression of viral products.

Adeno-associated viral (AAV) vectors allow for site-specific and time-dependent genetic manipulation of neurons. However, for successful implementation of AAV vectors, major consideration must be given to the selection of viral serotype and route of delivery for efficient gene transfer into the cell type being investigated. Here we compare the transduction pattern of neurons in the somatosensory system following injection of AAV9 or AAV2retro in the parabrachial complex of the midbrain, the spinal cord dorsal horn, the intrathecal space, and the colon. Transduction was evaluated based on Cre-dependent expression of tdTomato in transgenic reporter mice, following delivery of AAV9 or AAV2retro carrying identical constructs that drive the expression of Cre/GFP. The pattern of distribution of tdTomato expression indicated notable differences in the access of the two AAV serotypes to primary afferent neurons via peripheral delivery in the colon and to spinal projections neurons via intracranial delivery within the parabrachial complex. Additionally, our results highlight the superior sensitivity of detection of neuronal transduction based on reporter expression relative to expression of viral products.

Prenatal exposure to ethanol induces aberrant tangential migration of corticopetal GABAergic interneurons, and long-term alterations in the form and function of the prefrontal cortex. We have hypothesized that interneuronopathy contributes significantly to the pathoetiology of fetal alcohol spectrum disorders (FASD). Activity-dependent tangential migration of GABAergic cortical neurons is driven by depolarizing responses to ambient GABA present in the cortical enclave. We found that ethanol exposure potentiates the depolarizing action of GABA in GABAergic cortical interneurons of the embryonic mouse brain. Pharmacological antagonism of the cotransporter NKCC1 mitigated ethanol-induced potentiation of GABA depolarization and prevented aberrant patterns of tangential migration induced by ethanol in vitro. In a model of FASD, maternal bumetanide treatment prevented interneuronopathy in the prefrontal cortex of ethanol exposed offspring, including deficits in behavioral flexibility. These findings position interneuronopathy as a mechanism of FASD symptomatology, and posit NKCC1 as a pharmacological target for the management of FASD.

Neuroplasticity in the dorsal horn following peripheral nerve damage contributes critically to the establishment of chronic pain. The neurosecretory protein VGF (non-acronymic) is rapidly and robustly upregulated following nerve injury, and therefore peptides generated from it are positioned to serve as signals for peripheral damage. The goal of this project was to understand the spinal modulatory effects of the C-terminal VGF derived peptide TLQP-62 at the cellular level and gain insight into the function of the peptide in the development of neuropathic pain. In a rodent model of neuropathic pain, we demonstrate that endogenous levels of TLQP-62 increased in spinal cord, and its immunoneutralization led to prolonged attenuation of the development of nerve injury-induced hypersensitivity. Using multiphoton imaging of submaximal glutamate-induced Ca(2+) responses in spinal cord slices, we demonstrate the ability of TLQP-62 to potentiate glutamatergic responses in the dorsal horn. We further demonstrate that the peptide selectively potentiates responses of high threshold spinal neurons to mechanical stimuli in singe-unit in vivo recordings. These findings are consistent with a function of TLQP-62 in spinal plasticity that may contribute to central sensitization following nerve damage.

A 70-year-old man was admitted to our hospital for a penile circumcision due to phimosis using continuous dose spinal anaesthesia. On postoperative day 10 he came to the emergency department with a superficial abscess localised at the injection site of the spinal catheter. He was treated with intravenous antibiotics for 10 days, and the superficial abscess was incised and drained. Ten days later, the patient was readmitted to the emergency department with complaints of back pain and fever. A repeat MRI scan of his lumbar sacral area was done and showed epidural abscesses without any compression of the medulla or the myelum. The patient did not have any signs of spinal cord or nerve root compression at that time. He was treated with intravenous antibiotics with resolution of symptoms.

Food-borne infection with enterohemorrhagicEscherichia coli(EHEC) is a major cause of diarrheal illness in humans, and can lead to severe complications such as hemolytic uremic syndrome. Cattle and other ruminants are the main reservoir of EHEC, which enters the food-chain through contaminated meat, dairy, or vegetables. However, how EHEC transitions from the transmission vector to colonizing the intestinal tract, and how virulence-specific genes are regulated during this transition, is not well understood. Here, we describe the establishment of a vertebrate model for food-borne EHEC infection, using the protozoanParamecium caudatumas a vector and the zebrafish (Danio rerio) as a host. At 4 days post fertilization, zebrafish have a fully developed intestinal tract, yet are fully transparent. This allows us to follow intestinal colonization, microbe-host cell interactions, and microbial gene induction within the live host and in real time throughout the infection. Additionally, this model can be adapted to compare food- and water-borne infections, under gnotobiotic conditions or against the backdrop of an endogenous (and variable) host microbiota. Finally, the zebrafish allows for investigation of factors affecting shedding and transmission of bacteria to naïve hosts. High-resolution analysis of EHEC gene expression within the zebrafish host emphasizes the need for tight transcriptional regulation of virulence factors for within-host fitness.IMPORTANCEEnterohemorrhagicEscherichia coli(EHEC) is a food-borne pathogen which can cause diarrhea, vomiting and in some cases, severe complications such as kidney problems in humans. Up to 30% of cattle are colonized with EHEC, which can enter the food-chain through contaminated meat, dairy and vegetables. In order to control infections and stop transmission, it is important to understand what factors allow EHEC to colonize its hosts, cause virulence and aid transmission. Since this cannot be systematically studied in humans, it is important to develop animal models of infection and transmission. We developed a model which allows us to study food-borne infection in zebrafish, a vertebrate host that is transparent and genetically tractable. Using the zebrafish host, we can follow the bacterial infection cycle in real time, and gain important information regarding bacterial physiology and microbe-host interactions. This will allow us to identify potential new targets for infection control and prevention.

The neurosecretory protein VGF (non-acronymic) is rapidly and robustly upregulated by primary somatosensory afferent neurons following peripheral nerve damage. VGF is proteolytically processed to yield a number of bioactive peptides, including the C-terminal peptide TLQP-62. Our work demonstrates that spinal TLQP-62 increases after nerve injury and that immunoneutralization of C-terminal VGF peptides attenuates the development of mechanical allodynia. This peptide has been shown to induce BDNF-dependent neuronal plasticity in the hippocampus. We have shown that TLQP-62 induces potentiation of glutamatergic responses in a subset of dorsal horn neurons and exposure of spinal cord slices to TLQP-62 increases TrkB phosphorylation, suggesting that TLQP-62 may facilitate BDNF release. Since primary afferent neurons are a potential source of spinal BDNF, we examined the effects of TLQP-62 on these neurons. Using mice that express a genetically encoded calcium indicator restricted to primary afferent neurons (Pirt-GCamp3 mice), we observed that TLQP-62 induced calcium transients in a subset of primary afferent fibers in the dorsal horn of spinal cord slices. The responses occurred immediately after TLQP-62 exposure and were sustained during prolonged exposure. TLQP-62 also induced calcium transients in DRG cultures, both in capsaicin-responsive neurites, as well as in neurites that did not respond to capsaicin. Ongoing work is investigating the functional consequences of these TLQP-62 effects and their relationship to BDNF via patch-clamp and BDNF-pHluorin imaging, respectively. Our observations of TLQP-62-induced calcium responses in the processes of primary afferent neurons are consistent with the idea that the peptide may modulate neurotransmitter release.