Abstract: Immune checkpoint blockade involves targeting immune
regulatory molecules with antibodies. Preclinically, complex multiantibody
regimes of both inhibitory and stimulatory targets are a promising
candidate for the next generation of immunotherapy. However, in this
setting, the antibody platform may be limited due to excessive toxicity
caused by off target effects as a result of systemic administration. RNA
can be used as an alternate to antibodies as it can both downregulate
immunosuppressive checkpoints (siRNA) or induce expression of
immunostimulatory checkpoints (mRNA). In this study, we demonstrate
that the combination of both siRNA and mRNA in a single
formulation can simultaneously knockdown and induce expression of
immune checkpoint targets, thereby reprogramming the tumor
microenvironment from immunosuppressive to immunostimulatory
phenotype. To achieve this, RNA constructs were synthesized and
formulated into stable nucleic acid lipid nanoparticles (SNALPs); the SNALPs produced were 140−150 nm in size with >80%
loading efficiency. SNALPs could transfect macrophages and B16F10 cells in vitro resulting in 75% knockdown of inhibitory
checkpoint (PDL1) expression and simultaneously express high levels of stimulatory checkpoint (OX40L) with minimal
toxicity. Intratumoral treatment with the proposed formulation resulted in statistically reduced tumor growth, a greater
density of CD4+ and CD8+ infiltrates in the tumor, and immune activation within tumor-draining lymph nodes. These data
suggest that a single RNA-based formulation can successfully reprogram multiple immune checkpoint interactions on a
cellular level. Such a candidate may be able to replace future immune checkpoint therapeutic regimes composed of both
stimulatory- and inhibitory-receptor-targeting antibodies.

Abstract: Two-dimensional (2D) Janus materials are a new class of materials with unique physical, chemical, and quantum properties. The name “Janus” originates from the ancient Roman god which has two faces, one looking to the future while the other facing the past. Janus has been used to describe special types of materials which have two faces at the nanoscale. This unique atomic arrangement has been shown to present rather exotic properties with applications in biology, chemistry, energy conversion, and quantum sciences. This review article aims to offer a comprehensive review of the emergent quantum properties of Janus materials. The review starts by introducing 0D Janus nanoparticles and 1D Janus nanotubes, and highlights their difference from classical ones. The design principles, synthesis, and the properties of graphene-based and chalcogenide-based Janus layers are then discussed. A particular emphasis is given to colossal built-in potential in 2D Janus layers and resulting quantum phenomena such as Rashba splitting, skyrmionics, excitonics, and 2D magnetic ordering. More recent theoretical predictions are discussed in 2D Janus superlattices when Janus layers are stacked onto each other. Finally, we discuss the tunable quantum properties and newly predicted 2D Janus layers waiting to be experimentally realized. The review serves as a complete summary of the 2D Janus library and predicted quantum properties in 2D Janus layers and their superlattices.