Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine implicated in the pathogenesis of inflammation and cancer. It is produced by various cells and circulating MIF has been identified as a biomarker for a range of diseases. Extracellular MIF mainly binds to the cluster of differentiation 74 (CD74)/CD44 to activate downstream signaling pathways. These in turn activate immune responses, enhance inflammation and can promote cancer cell proliferation and invasion. Extracellular MIF also binds to the C-X-C chemokine receptors cooperating with or without CD74 to activate chemokine response. Intracellular MIF is involved in Toll-like receptor and inflammasome-mediated inflammatory response. Pharmacological inhibition of MIF has been shown to hold great promise in treating inflammatory diseases and cancer, including small molecule MIF inhibitors targeting the tautomerase active site of MIF and antibodies that neutralize MIF. In the current review, we discuss the role of MIF signaling pathways in inflammation and cancer and summarize the recent advances of the role of MIF in experimental and clinical exocrine pancreatic diseases. We expect to provide insights into clinical translation of MIF antagonism as a strategy for treating acute pancreatitis and pancreatic cancer.

Extracellular vesicle (EV)–based immunotherapeutics have emerged as promising strategy for treating diseases, and thus, a better understanding of the factors that regulate EV secretion and function can provide insights into developing advanced therapies. Here, we report that nutrient availability, even changes in individual nutrient components, may affect EV biogenesis and composition of immune cells [e.g., macrophages (Mφs)]. As a proof of concept, EVs from M1-Mφ under glutamine-depleted conditions (EV ^GLN− ) had higher yields, functional compositions, and immunostimulatory potential than EVs from conventional GLN-present medium (EV ^GLN+ ). Mechanistically, the systemic metabolic rewiring (e.g., altered energy and redox metabolism) induced by GLN depletion resulted in up-regulated pathways related to EV biogenesis/cargo sorting (e.g., ESCRT) and immunostimulatory molecule production (e.g., NF-κB and STAT) in Mφs. This study highlights the importance of nutrient status in EV secretion and function, and optimizing metabolic states and/or integrating them with other engineering methods may advance the development of EV therapeutics.

Acute pancreatitis (AP) is a potentially fatal condition with no targeted treatment options. Although inhibiting xanthine oxidase (XO) in the treatment of AP has been studied in several experimental models and clinical trials, whether XO is a target of AP and what its the main mechanism of action is remains unclear. Here, we aimed to re-evaluate whether XO is a target aggravating AP other than merely generating reactive oxygen species that trigger AP. We first revealed that XO expression and enzyme activity were significantly elevated in the serum and pancreas of necrotizing AP models. We also found that allopurinol and febuxostat, as purine-like and non-purine XO inhibitors, respectively, exhibited protective effects against pancreatic acinar cell death in vitro and pancreatic damage in vivo at different doses and treatment time points. Moreover, we observed that conditional Xdh overexpression aggravated pancreatic necrosis and severity. Further mechanism analysis showed that XO inhibition restored the hypoxia-inducible factor 1-alpha (HIF-1α)-regulated lactate dehydrogenase A (LDHA) and NOD-like receptor family pyrin domain containing 3 (NLRP3) signaling pathways and reduced the enrichment of ¹³C₆-glucose to ¹³C₃-lactate. Lastly, we observed that clinical circulatory XO activity was significantly elevated in severe cases and correlated with C-reactive protein levels, while pancreatic XO and urate were also increased in severe AP patients. These results together indicated that proper inhibition of XO might be a promising therapeutic strategy for alleviating pancreatic necrosis and preventing progression of severe AP by downregulating HIF-1α-mediated LDHA and NLRP3 signaling pathways.

A large population in the world has been infected by COVID-19. Understanding the mechanisms of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) is important for the management and treatment of COVID-19. When it comes to the infection process, one of the most important proteins in SARS-CoV-2 is the spike (S) protein, which is able to bind to human Angiotensin-Converting Enzyme 2 (ACE2) and initializes the entry of the host cell. In this study, we implemented multiscale computational approaches to study the electrostatic features of the interfaces of the SARS-CoV-2 S protein receptor binding domain and ACE2. The simulations and analyses were performed on high-performance computing resources in the Texas Advanced Computing Center. Our study identified key residues on SARS-CoV-2, which can be used as targets for future drug design. The results shed light on future drug design and therapeutic targets for COVID-19.