Wei Shi

Establishment of an in vivo small animal model of human tumor and human immune system interaction would enable preclinical investigations into the mechanisms underlying cancer immunotherapy. To this end, nonobese diabetic ( NOD).Cg‐Prkdc scid IL2rg tm1Wjl /Sz (null; NSG) mice were transplanted with human (h)CD34 + hematopoietic progenitor and stem cells, which leads to the development of human hematopoietic and immune systems [humanized NSG (HuNSG)]. HuNSG mice received human leukocyte antigen partially matched tumor implants from patient‐ derived xenografts [PDX; non ‐ small cell lung cancer (NSCLC), sarcoma, bladder cancer, and triple‐negative breast cancer (TNBC)] or from a TNBC cell line‐derived xenograft (CDX). Tumor growth curves were similar in HuNSG compared with nonhuman immune‐engrafted NSG mice. Treatment with pembrolizumab, which targets programmed cell death protein 1, produced significant growth inhibition in both CDX and PDX tumors in HuNSG but not in NSG mice. Finally, inhibition of tumor growth was dependent on hCD8 + T cells, as demonstrated by antibody‐mediated depletion. Thus, tumor‐bearing HuNSG mice may represent an important, new model for preclinical immunotherapy research.—Wang, M., Yao, L.‐C., Cheng, M., Cai, D., Martinek, J., Pan, C.‐X., Shi, W., Ma, A.‐H., De Vere White, R. W., Airhart, S., Liu, E. T., Banchereau, J., Brehm, M. A., Greiner, D. L., Shultz, L. D., Palucka, K., Keck, J. G. Humanized mice in studying efficacy and mechanisms of PD‐1‐targeted cancer immunotherapy. FASEB J. 32,1537 ‐1549 (2018). www.fasebj.org

Melatonin has demonstrated a potential protective effect in central nervous system. Thus, it is interesting to determine whether pre-ischemia melatonin administration could protect against cerebral ischemia/reperfusion (IR)-related injury and the underlying molecular mechanisms. In this study, we revealed that IR injury significantly activated endoplasmic reticulum (ER) stress and autophagy in a middle cerebral artery occlusion mouse model. Pre-ischemia melatonin treatment was able to attenuate IR-induced ER stress and autophagy. In addition, with tandem RFP-GFP-LC3 adeno-associated virus, we demonstrated pre-ischemic melatonin significantly alleviated IR-induced autophagic flux. Furthermore, we showed that IR induced neuronal apoptosis through ER stress related signalings. Moreover, IR-induced autophagy was significantly blocked by ER stress inhibitor (4-PBA), as well as ER-related signaling inhibitors (PERK inhibitor, GSK; IRE1 inhibitor, 3,5-dibromosalicylaldehyde). Finally, we revealed that melatonin significantly alleviated cerebral infarction, brain edema, neuronal apoptosis, and neurological deficiency, which were remarkably abolished by tunicamycin (ER stress activator) and rapamycin (autophagy activator), respectively. In summary, our study provides strong evidence that pre-ischemia melatonin administration significantly protects against cerebral IR injury through inhibiting ER stress-dependent autophagy. Our findings shed light on the novel preventive and therapeutic strategy of daily administration of melatonin, especially among the population with high risk of cerebral ischemic stroke.

Abstract Rhombohedral NaZr 2 (PO 4 ) 3 is the prototype of all the NASICON‐type materials. The ionic diffusion in these rhombohedral NASICON materials is highly influenced by the ionic migration channels and the bottlenecks in the channels which have been extensively studied. However, no consensus is reached as to which one is the preferential ionic migration channel. Moreover, the relationships between the Na + distribution over the multiple available sites, concerted migration, and diffusion properties remain elusive. Using ab initio molecular dynamics simulations, here it is shown that the Na + ions tend to migrate through the Na1–Na3–Na2–Na3–Na1 channels rather than through the Na2–Na3–Na3–Na2 channels. There are two types of concerted migration mechanisms: two Na + ions located at the adjacent Na1 and Na2 sites can migrate either in the same direction or at an angle. Both mechanisms exhibit relatively low migration barriers owing to the potential energy conversion during the Na + ions migration process. Redistribution of Na + ions from the most stable Na1 sites to Na2 on increasing Na + total content further facilitates the concerted migration and promotes the Na + ion mobility. The work establishes a connection between the Na + concentration in rhombohedral NASICON materials and their diffusion properties.