Research progress on roles of ultraviolet irradiation in diseases

The electromagnetic spectrum emitted by the sun includes visible light, infrared, and ultraviolet (UV). Among them, UV is one of the hotspots of research. Previous studies have paid more attention to the impact of UV on the skin because UV is one of the causes of skin damage. The physiological effects of UV on the skin are well understood, but its impacts on other organs of the body and other human diseases are unclear yet. This review pointed to the benefits of UV exposure in reducing weight gain, metabolic dysfunction, and cardiovascular disease. In addition, UV exposure may be helpful in reducing the incidence of diseases such as diabetes and colitis. UV may also play a role in inhibiting the development of myopia and depression. These findings provide new ideas for applying UV in the treatment of human diseases in the future. This paper reviewed the impacts of UV exposure on human non-skin diseases and explored the possibility of damage of acute UV exposure to organs, not only at the skin level, clarified the benefits and harms of UV for human body, and provided theoretical reference and research directions for deep UV exploitation and UV dose control

Demystifying Structural Disparity in Graph Neural Networks: Can One Size Fit All?

Recent studies on Graph Neural Networks(GNNs) provide both empirical and theoretical evidence supporting their effectiveness in capturing structural patterns on both homophilic and certain heterophilic graphs. Notably, most real-world homophilic and heterophilic graphs are comprised of a mixture of nodes in both homophilic and heterophilic structural patterns, exhibiting a structural disparity. However, the analysis of GNN performance with respect to nodes exhibiting different structural patterns, e.g., homophilic nodes in heterophilic graphs, remains rather limited. In the present study, we provide evidence that Graph Neural Networks(GNNs) on node classification typically perform admirably on homophilic nodes within homophilic graphs and heterophilic nodes within heterophilic graphs while struggling on the opposite node set, exhibiting a performance disparity. We theoretically and empirically identify effects of GNNs on testing nodes exhibiting distinct structural patterns. We then propose a rigorous, non-i.i.d PAC-Bayesian generalization bound for GNNs, revealing reasons for the performance disparity, namely the aggregated feature distance and homophily ratio difference between training and testing nodes. Furthermore, we demonstrate the practical implications of our new findings via (1) elucidating the effectiveness of deeper GNNs; and (2) revealing an over-looked distribution shift factor on graph out-of-distribution problem and proposing a new scenario accordingly.Comment: 54 pages, 24 figure

Carcinomas assemble a filamentous CXCL12-keratin-19 coating that suppresses T cell-mediated immune attack.

Cancer immunotherapy frequently fails because most carcinomas have few T cells, suggesting that cancers can suppress T cell infiltration. Here, we show that cancer cells of human pancreatic ductal adenocarcinoma (PDA), colorectal cancer, and breast cancer are coated with transglutaminase-2 (TGM2)-dependent covalent CXCL12-keratin-19 (KRT19) heterodimers that are organized as filamentous networks. Since a dimeric form of CXCL12 suppresses the motility of human T cells, we determined whether this polymeric CXCL12-KRT19 coating mediated T cell exclusion. Mouse tumors containing control PDA cells exhibited the CXCL12-KRT19 coating, excluded T cells, and did not respond to treatment with anti-PD-1 antibody. Tumors containing PDA cells not expressing either KRT19 or TGM2 lacked the CXCL12-KRT19 coating, were infiltrated with activated CD8+ T cells, and growth was suppressed with anti-PD-1 antibody treatment. Thus, carcinomas assemble a CXCL12-KRT19 coating to evade cancer immune attack

Pancreatic cancer cells assemble a CXCL12-keratin 19 coating to resist immunotherapy

How pancreatic ductal adenocarcinoma (PDA) cells stimulate CXCR4 to exclude T cells and resist T cell checkpoint inhibitors is not known. Here, we find that CXCL12, the ligand for CXCR4 that is produced by the cancer-associated fibroblast, “coats” human PDA and colorectal cancer cells as covalent heterodimers with keratin 19 (KRT19). Modeling the formation of the heterodimer with three proteins shows that KRT19 binds CXCL12 and transglutaminase-2 (TGM2), and that TGM2 converts the reversible KRT19-CXCL12 complex into a covalent heterodimer. We validate this model by showing that cancer cells in mouse PDA tumors must express KRT19 and TGM2 to become coated with CXCL12, exclude T cells, and resist immunotherapy with anti-PD-1 antibody. Thus, PDA cells have a cell-autonomous means by which they capture CXCL12 to mediate immune suppression, which is potentially amenable to therapy. One Sentence Summary Cancer cells in pancreatic ductal adenocarcinoma use transglutaminase-2 to assemble a coating comprised of covalent CXCL12-keratin 19 heterodimers that excludes T cells and mediates resistance to inhibition of the PD-1 T cell checkpoint

Production and characterization of a recombinant single-chain antibody against Hantaan virus envelop glycoprotein

Hantaan virus (HTNV) is the type of Hantavirus causing hemorrhagic fever with renal syndrome, for which no specific therapeutics are available so far. Cell type-specific internalizing antibodies can be used to deliver therapeutics intracellularly to target cell and thus, have potential application in anti-HTNV infection. To achieve intracellular delivery of therapeutics, it is necessary to obtain antibodies that demonstrate sufficient cell type-specific binding, internalizing, and desired cellular trafficking. Here, we describe the prokaryotic expression, affinity purification, and functional testing of a single-chain Fv antibody fragment (scFv) against HTNV envelop glycoprotein (GP), an HTNV-specific antigen normally located on the membranes of HTNV-infected cells. This HTNV GP-targeting antibody, scFv3G1, was produced in the cytoplasm of Escherichia coli cells as a soluble protein and was purified by immobilized metal affinity chromatography. The purified scFv possessed a high specific antigen-binding activity to HTNV GP and HTNV-infected Vero E6 cells and could be internalized into HTNV-infected cells probably through the clathrin-dependent endocytosis pathways similar to that observed with transferrin. Our results showed that the E. coli-produced scFv had potential applications in targeted and intracellular delivery of therapeutics against HTNV infections