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Patton, T.

Publications and source records attributed to Patton, T..

5 recordsLinked to original sources

Immunological responses to hydrogel-aided induced pluripotent stem cell-derived dopaminergic progenitor transplants in immunodeficient versus cyclosporine immunosuppressed rats.

The success of stem cell-derived brain repair for Parkinsons is limited by the variable survival and poor maturation of dopaminergic progenitors after transplantation into the Parkinsonian brain. One approach that has been developed to improve this is engraftment of the cells within a neurotrophin-enriched collagen hydrogel. Although this has been shown to improve progenitor survival and maturation in athymic nude rats, the same beneficial effects of the hydrogel were not seen in cyclosporine immunosuppressed rats. To determine the reasons for these differences, the aim of this study was to assess the local and systemic immune responses to progenitor transplantation in these two recipient groups. To do so, human induced pluripotent stem cell-derived dopaminergic progenitors were transplanted into 6-hydroxydopamine-lesioned striatum of athymic or cyclosporine immunosuppressed rats. The cells were transplanted either alone, with the neurotrophins GDNF and BDNF, in an unloaded collagen hydrogel, or in a neurotrophin-loaded collagen hydrogel. Post-mortem assessment included both graft site and blood analysis of immune cell populations. As expected, nude rats showed a pronounced innate immune cell response at the graft site but no T-cell recruitment or activation locally or systemically. In contrast, while the immunosuppressed rats also showed the expected innate immune cells response to the transplant, there was also infiltration of CD4+ and CD8+ T cells at the site of transplantation as well as circulating activated T-cells. Thus, this study suggests that the benefits of the hydrogel that were seen in the athymic nude rats did not manifest in the cyclosporine immunosuppressed rats due to incomplete immunosupression. This study shows the importance of careful optimisation of the immunosuppressive regime chosen before xenotransplantation experiments.

neuroscience↗

Sex and breeding stage differences in neurogenomic profiles reflect hormone signaling in a socially polyandrous shorebird

In sex-role reversed species, females are socially polyandrous and compete for multiple mates, whereas males conduct the majority of parental care. To understand the extent to which physiological differences between females and males are shaped by sex roles, we examined sex differences in gene expression in sex-role reversed northern jacanas (Jacana spinosa). Given that females compete for mating opportunities, and males cycle between courtship and parental care, we predicted that transcriptomic profiles would be more similar between females and courting males, in contrast to female and parenting males. Leveraging a high quality de novo genome assembly, we conducted RNA-seq on two brain regions associated with the regulation of social behavior: the preoptic area of the hypothalamus and the nucleus taeniae. The majority of genes differentially expressed between the sexes were male-biased. Of these male-biased genes, the majority were located on the Z-chromosome. Contrary to our prediction, the greatest difference in autosomal gene expression was between females and courting males, in the preoptic area of the hypothalamus. Several differentially expressed genes related to elements of hormone signaling that are likely to be behaviorally salient, including higher expression of androgen receptor in females relative to parenting males, and higher expression of prolactin receptor in males, regardless of breeding stage. Some sex-associated gene networks were also associated with competitive traits, whereas others were associated with aggressive behaviors, regardless of sex. Few genes were differentially expressed between courting and parenting males, yet some nonetheless had connections to behavioral endocrinology, including prolactin, thyroid and insulin-like growth factor pathways. Our investigation of sex differences in gene expression can help to reveal the molecular mechanisms underlying female competition and male parental care in socially polyandrous species. We conclude that social polyandry is not a simple reversal in the direction of sex-biased gene expression in the brain, but rather a result of complex genetic and hormonal interactions that warrants further study.

genomics↗

Toll-like receptor 7 (TLR7)-mediated antiviral response protects mice from lethal SARS-CoV-2 infection

SARS-CoV-2-induced impaired antiviral and excessive inflammatory responses cause fatal pneumonia. However, the key pattern recognition receptors that elicit effective antiviral and lethal inflammatory responses in-vivo are not well defined. CoVs possess single-stranded RNA (ssRNA) genome that is abundantly produced during infection and stimulates both antiviral interferon (IFN) and inflammatory cytokine/ chemokine responses. Therefore, in this study, using wild-type control and TLR7 deficient BALB/c mice infected with a mouse-adapted SARS-COV-2 (MA-CoV-2), we evaluated the role of TLR7 signaling in MA-CoV-2-induced antiviral and inflammatory responses and disease outcome. We show that TLR7-deficient mice are more susceptible to MA-CoV-2 infection as compared to infected control mice. Further evaluation of MA-CoV-2 infected lungs showed significantly reduced mRNA levels of antiviral type I (IFN/{beta}) and type III (IFN{lambda}) IFNs, IFN stimulated genes (ISGs, ISG15 and CXCL10), and several pro-inflammatory cytokines/chemokines in TLR7 deficient compared to control mice. Reduced lung IFN/ISG levels and increased morbidity/mortality in TLR7 deficient mice correlated with high lung viral titer. Detailed examination of total cells from MA-CoV-2 infected lungs showed high neutrophil count in TLR7 deficient mice compared to control mice. Additionally, blocking TLR7 activity post-MA-CoV-2 infection using a specific inhibitor also enhanced disease severity. In summary, our results conclusively establish that TLR7 signaling is protective during SARS-CoV-2 infection, and despite robust inflammatory response, TLR7-mediated IFN/ISG responses likely protect the host from lethal disease. Given similar outcomes in control and TLR7 deficient humans and mice, these results show that MA-CoV-2 infected mice serve as excellent model to study COVID-19.

immunology↗

The Children's Brain Tumor Network (CBTN) - Accelerating Research in Pediatric Central Nervous System Tumors through Collaboration and Open Science

Pediatric brain tumors are the leading cause of cancer-related death in children in the United States and contribute a disproportionate number of potential years of life lost compared to adult cancers. Moreover, survivors frequently suffer long-term side effects, including secondary cancers. The Childrens Brain Tumor Network (CBTN) is a multi-institutional international clinical research consortium created to advance therapeutic development through the collection and rapid distribution of biospecimens and data via open-science research platforms for real-time access and use by the global research community. The CBTNs 32 member institutions utilize a shared regulatory governance architecture at the Childrens Hospital of Philadelphia to accelerate and maximize the use of biospecimens and data. As of August 2022, CBTN has enrolled over 4,700 subjects, over 1,500 parents, and collected over 65,000 biospecimen aliquots for research. Additionally, over 80 preclinical models have been developed from collected tumors. Multi-omic data for over 1,000 tumors and germline material is currently available with data generation for > 5,000 samples underway. To our knowledge, CBTN provides the largest open-access pediatric brain tumor multi-omic dataset annotated with longitudinal clinical and outcome data, imaging, associated biospecimens, child-parent genomic pedigrees, and in vivo and in vitro preclinical models. Empowered by NIH-supported platforms such as the Kids First Data Resource and the Childhood Cancer Data Initiative, the CBTN continues to expand the resources needed for scientists to accelerate translational impact for improved outcomes and quality of life for children with brain and spinal cord tumors.

cancer biology↗

In pursuit of biomarkers for predicting susceptibility to activity-based anorexia (ABA) in adolescent female rats

Anorexia nervosa (AN) has high rates of mortality and low rates of recovery, with outcomes that worsen with illness duration. Improved early intervention strategies are required and identifying risk factors that contribute to the development of AN is critical to their implementation. The development of AN often follows a pre-existing diagnosis of anxiety disorders and obsessive-compulsive disorder and substantial genetic overlap between these conditions suggest common underlying features may predict vulnerability to AN. Moreover, patients with AN have increased levels of circulating proinflammatory cytokines, which may be involved in susceptibility to pathological weight loss considering that children with immune dysfunction have a higher risk of subsequent AN diagnoses. Here, we used the activity-based anorexia (ABA) model to examine whether baseline levels of locomotion, anxiety-like behaviour, compulsive behaviour, and circulating immune markers predict the subsequent development of pathological weight loss in adolescent female rats. While none of these primary features were shown to differentiate rats that went on to be susceptible or resistant to weight loss in ABA, increased locomotion and anxiety-like behaviour were both associated with the extent of weight loss in susceptible but not resistant animals. Intriguingly, behaviour related to poor decision-making in a situation of conflict was shown to predict vulnerability to ABA. Future research using the ABA model to uncover early predictors of AN should focus on translationally relevant assays of decision-making and cognitive behaviour, dysfunction of which may not only predispose animals to ABA but may also represent an endophenotype linking anorectic, anxiety-like and compulsive behaviour.

animal behavior and cognition↗