Pediatric medulloblastoma express immune checkpoint B7-H3

PURPOSE: Medulloblastomas (MB) are highly malignant brain tumors that predominantly occur in young infants. Immunotherapy to boost the immune system is emerging as a novel promising approach, but is often hampered by inhibitory immune checkpoints. In the present study, we have studied immune checkpoint B7-H3 expression in a tissue cohort of human pediatric MB. METHODS: Expression of B7-H3 was detected by immunohistochemistry and classified via B7-H3 staining intensity and percentage of B7-H3 positive tumor cells. Subsequently, B7-H3 protein expression was distinguished in MB molecular subtypes and correlated to immune cell infiltrates, patient characteristics, and survival. RESULTS: B7-H3 protein expression was found in 23 out of 24 (96%) human pediatric MB cases and in 17 out of 24 (71%) MB cases > 25% of tumor cells had any level of B7-H3 expression. B7-H3 protein expression was more frequent on Group-4 MB as compared with other molecular subtypes (p = 0.02). Tumors with high B7-H3 expression showed less influx of γδT cells (p = 0.002) and CD3+ T cells (p = 0.041). CONCLUSION: Immune checkpoint B7-H3 is differentially expressed by the large majority of pediatric MB. This further warrants the development of novel B7-H3-directed (immuno)therapeutic methods for children with incurable, metastatic, or chemo-resistant MB

Effects of Electric Field on the Vapor–Liquid Equilibria of Nanoconfined Methanol and Ethanol

The effects of the electric field on the vapor-liquid equilibria of methanol and ethanol confined in a graphitic slit pore of width 4 nm using molecular dynamics simulations are reported. The vapor-liquid critical temperature of methanol gets suppressed under confinement. The external electrical field further decreases the critical temperature with increasing electric field strength up to E = 1.5 V·nm-1. Surprisingly, a further increase in the electric field strength reverses the critical temperature behavior and is seen to increase with increasing electric field. The reversible behavior of the critical temperature with the electric field is also seen for nanoconfined ethanol at approximately 1.5 V·nm-1. The critical density, on the other hand, is found to continuously decrease with increasing electric field strength. Application of an external electric field results in the decrease in vapor and liquid densities. The coordination number in the liquid phase is found to decrease first with increasing electric field until E = 1.5 V·nm-1 and then increases with a further increase in the electric field, confirming the observed trend in the critical temperature according to the mean field theory. Orientational order of nanoconfined methanol and ethanol, on the other hand, is found to increase with increasing electric field